[FFmpeg-cvslog] snow: split snow in snowdec and snowenc

Luca Barbato git at videolan.org
Fri Nov 25 04:43:28 CET 2011


ffmpeg | branch: master | Luca Barbato <lu_zero at gentoo.org> | Wed Nov  2 10:10:40 2011 -0700| [7f1b427018ecff59e0e14031eecc79aac0d91ec8] | committer: Luca Barbato

snow: split snow in snowdec and snowenc

The common non inlined code goes in snow.c, the common inlined code in
snow.h, tables move in snowdata.h (included only by snow.c)

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=7f1b427018ecff59e0e14031eecc79aac0d91ec8
---

 libavcodec/Makefile   |   12 +-
 libavcodec/snow.c     | 3254 ++-----------------------------------------------
 libavcodec/snow.h     |  614 ++++++++++
 libavcodec/snowdata.h |  132 ++
 libavcodec/snowdec.c  |  546 +++++++++
 libavcodec/snowenc.c  | 1915 +++++++++++++++++++++++++++++
 6 files changed, 3314 insertions(+), 3159 deletions(-)

diff --git a/libavcodec/Makefile b/libavcodec/Makefile
index b9ed8db..37aa8ee 100644
--- a/libavcodec/Makefile
+++ b/libavcodec/Makefile
@@ -341,12 +341,12 @@ OBJS-$(CONFIG_SIPR_DECODER)            += sipr.o acelp_pitch_delay.o \
 OBJS-$(CONFIG_SMACKAUD_DECODER)        += smacker.o
 OBJS-$(CONFIG_SMACKER_DECODER)         += smacker.o
 OBJS-$(CONFIG_SMC_DECODER)             += smc.o
-OBJS-$(CONFIG_SNOW_DECODER)            += snow.o rangecoder.o
-OBJS-$(CONFIG_SNOW_ENCODER)            += snow.o rangecoder.o motion_est.o \
-                                          ratecontrol.o h263.o             \
-                                          mpegvideo.o error_resilience.o   \
-                                          ituh263enc.o mpegvideo_enc.o     \
-                                          mpeg12data.o
+OBJS-$(CONFIG_SNOW_DECODER)            += snowdec.o snow.o rangecoder.o
+OBJS-$(CONFIG_SNOW_ENCODER)            += snowenc.o snow.o rangecoder.o    \
+                                          motion_est.o ratecontrol.o       \
+                                          h263.o mpegvideo.o               \
+                                          error_resilience.o ituh263enc.o  \
+                                          mpegvideo_enc.o mpeg12data.o
 OBJS-$(CONFIG_SOL_DPCM_DECODER)        += dpcm.o
 OBJS-$(CONFIG_SP5X_DECODER)            += sp5xdec.o mjpegdec.o mjpeg.o
 OBJS-$(CONFIG_SRT_DECODER)             += srtdec.o ass.o
diff --git a/libavcodec/snow.c b/libavcodec/snow.c
index a3af577..a290358 100644
--- a/libavcodec/snow.c
+++ b/libavcodec/snow.c
@@ -25,480 +25,50 @@
 #include "dsputil.h"
 #include "dwt.h"
 #include "snow.h"
+#include "snowdata.h"
 
 #include "rangecoder.h"
 #include "mathops.h"
-
-#include "mpegvideo.h"
 #include "h263.h"
 
 #undef NDEBUG
 #include <assert.h>
 
-static const int8_t quant3bA[256]={
- 0, 0, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1,
- 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1,
- 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1,
- 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1,
- 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1,
- 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1,
- 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1,
- 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1,
- 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1,
- 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1,
- 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1,
- 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1,
- 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1,
- 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1,
- 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1,
- 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1,
-};
-
-static const uint8_t obmc32[1024]={
-  0,  0,  0,  0,  4,  4,  4,  4,  4,  4,  4,  4,  8,  8,  8,  8,  8,  8,  8,  8,  4,  4,  4,  4,  4,  4,  4,  4,  0,  0,  0,  0,
-  0,  4,  4,  4,  8,  8,  8, 12, 12, 16, 16, 16, 20, 20, 20, 24, 24, 20, 20, 20, 16, 16, 16, 12, 12,  8,  8,  8,  4,  4,  4,  0,
-  0,  4,  8,  8, 12, 12, 16, 20, 20, 24, 28, 28, 32, 32, 36, 40, 40, 36, 32, 32, 28, 28, 24, 20, 20, 16, 12, 12,  8,  8,  4,  0,
-  0,  4,  8, 12, 16, 20, 24, 28, 28, 32, 36, 40, 44, 48, 52, 56, 56, 52, 48, 44, 40, 36, 32, 28, 28, 24, 20, 16, 12,  8,  4,  0,
-  4,  8, 12, 16, 20, 24, 28, 32, 40, 44, 48, 52, 56, 60, 64, 68, 68, 64, 60, 56, 52, 48, 44, 40, 32, 28, 24, 20, 16, 12,  8,  4,
-  4,  8, 12, 20, 24, 32, 36, 40, 48, 52, 56, 64, 68, 76, 80, 84, 84, 80, 76, 68, 64, 56, 52, 48, 40, 36, 32, 24, 20, 12,  8,  4,
-  4,  8, 16, 24, 28, 36, 44, 48, 56, 60, 68, 76, 80, 88, 96,100,100, 96, 88, 80, 76, 68, 60, 56, 48, 44, 36, 28, 24, 16,  8,  4,
-  4, 12, 20, 28, 32, 40, 48, 56, 64, 72, 80, 88, 92,100,108,116,116,108,100, 92, 88, 80, 72, 64, 56, 48, 40, 32, 28, 20, 12,  4,
-  4, 12, 20, 28, 40, 48, 56, 64, 72, 80, 88, 96,108,116,124,132,132,124,116,108, 96, 88, 80, 72, 64, 56, 48, 40, 28, 20, 12,  4,
-  4, 16, 24, 32, 44, 52, 60, 72, 80, 92,100,108,120,128,136,148,148,136,128,120,108,100, 92, 80, 72, 60, 52, 44, 32, 24, 16,  4,
-  4, 16, 28, 36, 48, 56, 68, 80, 88,100,112,120,132,140,152,164,164,152,140,132,120,112,100, 88, 80, 68, 56, 48, 36, 28, 16,  4,
-  4, 16, 28, 40, 52, 64, 76, 88, 96,108,120,132,144,156,168,180,180,168,156,144,132,120,108, 96, 88, 76, 64, 52, 40, 28, 16,  4,
-  8, 20, 32, 44, 56, 68, 80, 92,108,120,132,144,156,168,180,192,192,180,168,156,144,132,120,108, 92, 80, 68, 56, 44, 32, 20,  8,
-  8, 20, 32, 48, 60, 76, 88,100,116,128,140,156,168,184,196,208,208,196,184,168,156,140,128,116,100, 88, 76, 60, 48, 32, 20,  8,
-  8, 20, 36, 52, 64, 80, 96,108,124,136,152,168,180,196,212,224,224,212,196,180,168,152,136,124,108, 96, 80, 64, 52, 36, 20,  8,
-  8, 24, 40, 56, 68, 84,100,116,132,148,164,180,192,208,224,240,240,224,208,192,180,164,148,132,116,100, 84, 68, 56, 40, 24,  8,
-  8, 24, 40, 56, 68, 84,100,116,132,148,164,180,192,208,224,240,240,224,208,192,180,164,148,132,116,100, 84, 68, 56, 40, 24,  8,
-  8, 20, 36, 52, 64, 80, 96,108,124,136,152,168,180,196,212,224,224,212,196,180,168,152,136,124,108, 96, 80, 64, 52, 36, 20,  8,
-  8, 20, 32, 48, 60, 76, 88,100,116,128,140,156,168,184,196,208,208,196,184,168,156,140,128,116,100, 88, 76, 60, 48, 32, 20,  8,
-  8, 20, 32, 44, 56, 68, 80, 92,108,120,132,144,156,168,180,192,192,180,168,156,144,132,120,108, 92, 80, 68, 56, 44, 32, 20,  8,
-  4, 16, 28, 40, 52, 64, 76, 88, 96,108,120,132,144,156,168,180,180,168,156,144,132,120,108, 96, 88, 76, 64, 52, 40, 28, 16,  4,
-  4, 16, 28, 36, 48, 56, 68, 80, 88,100,112,120,132,140,152,164,164,152,140,132,120,112,100, 88, 80, 68, 56, 48, 36, 28, 16,  4,
-  4, 16, 24, 32, 44, 52, 60, 72, 80, 92,100,108,120,128,136,148,148,136,128,120,108,100, 92, 80, 72, 60, 52, 44, 32, 24, 16,  4,
-  4, 12, 20, 28, 40, 48, 56, 64, 72, 80, 88, 96,108,116,124,132,132,124,116,108, 96, 88, 80, 72, 64, 56, 48, 40, 28, 20, 12,  4,
-  4, 12, 20, 28, 32, 40, 48, 56, 64, 72, 80, 88, 92,100,108,116,116,108,100, 92, 88, 80, 72, 64, 56, 48, 40, 32, 28, 20, 12,  4,
-  4,  8, 16, 24, 28, 36, 44, 48, 56, 60, 68, 76, 80, 88, 96,100,100, 96, 88, 80, 76, 68, 60, 56, 48, 44, 36, 28, 24, 16,  8,  4,
-  4,  8, 12, 20, 24, 32, 36, 40, 48, 52, 56, 64, 68, 76, 80, 84, 84, 80, 76, 68, 64, 56, 52, 48, 40, 36, 32, 24, 20, 12,  8,  4,
-  4,  8, 12, 16, 20, 24, 28, 32, 40, 44, 48, 52, 56, 60, 64, 68, 68, 64, 60, 56, 52, 48, 44, 40, 32, 28, 24, 20, 16, 12,  8,  4,
-  0,  4,  8, 12, 16, 20, 24, 28, 28, 32, 36, 40, 44, 48, 52, 56, 56, 52, 48, 44, 40, 36, 32, 28, 28, 24, 20, 16, 12,  8,  4,  0,
-  0,  4,  8,  8, 12, 12, 16, 20, 20, 24, 28, 28, 32, 32, 36, 40, 40, 36, 32, 32, 28, 28, 24, 20, 20, 16, 12, 12,  8,  8,  4,  0,
-  0,  4,  4,  4,  8,  8,  8, 12, 12, 16, 16, 16, 20, 20, 20, 24, 24, 20, 20, 20, 16, 16, 16, 12, 12,  8,  8,  8,  4,  4,  4,  0,
-  0,  0,  0,  0,  4,  4,  4,  4,  4,  4,  4,  4,  8,  8,  8,  8,  8,  8,  8,  8,  4,  4,  4,  4,  4,  4,  4,  4,  0,  0,  0,  0,
- //error:0.000020
-};
-static const uint8_t obmc16[256]={
-  0,  4,  4,  8,  8, 12, 12, 16, 16, 12, 12,  8,  8,  4,  4,  0,
-  4,  8, 16, 20, 28, 32, 40, 44, 44, 40, 32, 28, 20, 16,  8,  4,
-  4, 16, 24, 36, 44, 56, 64, 76, 76, 64, 56, 44, 36, 24, 16,  4,
-  8, 20, 36, 48, 64, 76, 92,104,104, 92, 76, 64, 48, 36, 20,  8,
-  8, 28, 44, 64, 80,100,116,136,136,116,100, 80, 64, 44, 28,  8,
- 12, 32, 56, 76,100,120,144,164,164,144,120,100, 76, 56, 32, 12,
- 12, 40, 64, 92,116,144,168,196,196,168,144,116, 92, 64, 40, 12,
- 16, 44, 76,104,136,164,196,224,224,196,164,136,104, 76, 44, 16,
- 16, 44, 76,104,136,164,196,224,224,196,164,136,104, 76, 44, 16,
- 12, 40, 64, 92,116,144,168,196,196,168,144,116, 92, 64, 40, 12,
- 12, 32, 56, 76,100,120,144,164,164,144,120,100, 76, 56, 32, 12,
-  8, 28, 44, 64, 80,100,116,136,136,116,100, 80, 64, 44, 28,  8,
-  8, 20, 36, 48, 64, 76, 92,104,104, 92, 76, 64, 48, 36, 20,  8,
-  4, 16, 24, 36, 44, 56, 64, 76, 76, 64, 56, 44, 36, 24, 16,  4,
-  4,  8, 16, 20, 28, 32, 40, 44, 44, 40, 32, 28, 20, 16,  8,  4,
-  0,  4,  4,  8,  8, 12, 12, 16, 16, 12, 12,  8,  8,  4,  4,  0,
-//error:0.000015
-};
-
-//linear *64
-static const uint8_t obmc8[64]={
-  4, 12, 20, 28, 28, 20, 12,  4,
- 12, 36, 60, 84, 84, 60, 36, 12,
- 20, 60,100,140,140,100, 60, 20,
- 28, 84,140,196,196,140, 84, 28,
- 28, 84,140,196,196,140, 84, 28,
- 20, 60,100,140,140,100, 60, 20,
- 12, 36, 60, 84, 84, 60, 36, 12,
-  4, 12, 20, 28, 28, 20, 12,  4,
-//error:0.000000
-};
-
-//linear *64
-static const uint8_t obmc4[16]={
- 16, 48, 48, 16,
- 48,144,144, 48,
- 48,144,144, 48,
- 16, 48, 48, 16,
-//error:0.000000
-};
-
-static const uint8_t * const obmc_tab[4]={
-    obmc32, obmc16, obmc8, obmc4
-};
-
-static int scale_mv_ref[MAX_REF_FRAMES][MAX_REF_FRAMES];
-
-typedef struct BlockNode{
-    int16_t mx;
-    int16_t my;
-    uint8_t ref;
-    uint8_t color[3];
-    uint8_t type;
-//#define TYPE_SPLIT    1
-#define BLOCK_INTRA   1
-#define BLOCK_OPT     2
-//#define TYPE_NOCOLOR  4
-    uint8_t level; //FIXME merge into type?
-}BlockNode;
-
-static const BlockNode null_block= { //FIXME add border maybe
-    .color= {128,128,128},
-    .mx= 0,
-    .my= 0,
-    .ref= 0,
-    .type= 0,
-    .level= 0,
-};
-
-#define LOG2_MB_SIZE 4
-#define MB_SIZE (1<<LOG2_MB_SIZE)
-#define ENCODER_EXTRA_BITS 4
-#define HTAPS_MAX 8
-
-typedef struct x_and_coeff{
-    int16_t x;
-    uint16_t coeff;
-} x_and_coeff;
-
-typedef struct SubBand{
-    int level;
-    int stride;
-    int width;
-    int height;
-    int qlog;        ///< log(qscale)/log[2^(1/6)]
-    DWTELEM *buf;
-    IDWTELEM *ibuf;
-    int buf_x_offset;
-    int buf_y_offset;
-    int stride_line; ///< Stride measured in lines, not pixels.
-    x_and_coeff * x_coeff;
-    struct SubBand *parent;
-    uint8_t state[/*7*2*/ 7 + 512][32];
-}SubBand;
-
-typedef struct Plane{
-    int width;
-    int height;
-    SubBand band[MAX_DECOMPOSITIONS][4];
-
-    int htaps;
-    int8_t hcoeff[HTAPS_MAX/2];
-    int diag_mc;
-    int fast_mc;
-
-    int last_htaps;
-    int8_t last_hcoeff[HTAPS_MAX/2];
-    int last_diag_mc;
-}Plane;
-
-typedef struct SnowContext{
-    AVClass *class;
-    AVCodecContext *avctx;
-    RangeCoder c;
-    DSPContext dsp;
-    DWTContext dwt;
-    AVFrame new_picture;
-    AVFrame input_picture;              ///< new_picture with the internal linesizes
-    AVFrame current_picture;
-    AVFrame last_picture[MAX_REF_FRAMES];
-    uint8_t *halfpel_plane[MAX_REF_FRAMES][4][4];
-    AVFrame mconly_picture;
-//     uint8_t q_context[16];
-    uint8_t header_state[32];
-    uint8_t block_state[128 + 32*128];
-    int keyframe;
-    int always_reset;
-    int version;
-    int spatial_decomposition_type;
-    int last_spatial_decomposition_type;
-    int temporal_decomposition_type;
-    int spatial_decomposition_count;
-    int last_spatial_decomposition_count;
-    int temporal_decomposition_count;
-    int max_ref_frames;
-    int ref_frames;
-    int16_t (*ref_mvs[MAX_REF_FRAMES])[2];
-    uint32_t *ref_scores[MAX_REF_FRAMES];
-    DWTELEM *spatial_dwt_buffer;
-    IDWTELEM *spatial_idwt_buffer;
-    int colorspace_type;
-    int chroma_h_shift;
-    int chroma_v_shift;
-    int spatial_scalability;
-    int qlog;
-    int last_qlog;
-    int lambda;
-    int lambda2;
-    int pass1_rc;
-    int mv_scale;
-    int last_mv_scale;
-    int qbias;
-    int last_qbias;
-#define QBIAS_SHIFT 3
-    int b_width;
-    int b_height;
-    int block_max_depth;
-    int last_block_max_depth;
-    Plane plane[MAX_PLANES];
-    BlockNode *block;
-#define ME_CACHE_SIZE 1024
-    int me_cache[ME_CACHE_SIZE];
-    int me_cache_generation;
-    slice_buffer sb;
-    int memc_only;
-
-    MpegEncContext m; // needed for motion estimation, should not be used for anything else, the idea is to eventually make the motion estimation independent of MpegEncContext, so this will be removed then (FIXME/XXX)
-
-    uint8_t *scratchbuf;
-}SnowContext;
-
-#ifdef __sgi
-// Avoid a name clash on SGI IRIX
-#undef qexp
-#endif
-#define QEXPSHIFT (7-FRAC_BITS+8) //FIXME try to change this to 0
-static uint8_t qexp[QROOT];
-
-static inline void put_symbol(RangeCoder *c, uint8_t *state, int v, int is_signed){
-    int i;
-
-    if(v){
-        const int a= FFABS(v);
-        const int e= av_log2(a);
-        const int el= FFMIN(e, 10);
-        put_rac(c, state+0, 0);
-
-        for(i=0; i<el; i++){
-            put_rac(c, state+1+i, 1);  //1..10
-        }
-        for(; i<e; i++){
-            put_rac(c, state+1+9, 1);  //1..10
-        }
-        put_rac(c, state+1+FFMIN(i,9), 0);
-
-        for(i=e-1; i>=el; i--){
-            put_rac(c, state+22+9, (a>>i)&1); //22..31
-        }
-        for(; i>=0; i--){
-            put_rac(c, state+22+i, (a>>i)&1); //22..31
-        }
-
-        if(is_signed)
-            put_rac(c, state+11 + el, v < 0); //11..21
-    }else{
-        put_rac(c, state+0, 1);
-    }
-}
-
-static inline int get_symbol(RangeCoder *c, uint8_t *state, int is_signed){
-    if(get_rac(c, state+0))
-        return 0;
-    else{
-        int i, e, a;
-        e= 0;
-        while(get_rac(c, state+1 + FFMIN(e,9))){ //1..10
-            e++;
-        }
-
-        a= 1;
-        for(i=e-1; i>=0; i--){
-            a += a + get_rac(c, state+22 + FFMIN(i,9)); //22..31
-        }
-
-        e= -(is_signed && get_rac(c, state+11 + FFMIN(e,10))); //11..21
-        return (a^e)-e;
-    }
-}
-
-static inline void put_symbol2(RangeCoder *c, uint8_t *state, int v, int log2){
-    int i;
-    int r= log2>=0 ? 1<<log2 : 1;
-
-    assert(v>=0);
-    assert(log2>=-4);
-
-    while(v >= r){
-        put_rac(c, state+4+log2, 1);
-        v -= r;
-        log2++;
-        if(log2>0) r+=r;
-    }
-    put_rac(c, state+4+log2, 0);
-
-    for(i=log2-1; i>=0; i--){
-        put_rac(c, state+31-i, (v>>i)&1);
-    }
-}
-
-static inline int get_symbol2(RangeCoder *c, uint8_t *state, int log2){
-    int i;
-    int r= log2>=0 ? 1<<log2 : 1;
-    int v=0;
-
-    assert(log2>=-4);
-
-    while(get_rac(c, state+4+log2)){
-        v+= r;
-        log2++;
-        if(log2>0) r+=r;
-    }
-
-    for(i=log2-1; i>=0; i--){
-        v+= get_rac(c, state+31-i)<<i;
-    }
-
-    return v;
-}
-
-static inline void unpack_coeffs(SnowContext *s, SubBand *b, SubBand * parent, int orientation){
-    const int w= b->width;
-    const int h= b->height;
-    int x,y;
-
-    int run, runs;
-    x_and_coeff *xc= b->x_coeff;
-    x_and_coeff *prev_xc= NULL;
-    x_and_coeff *prev2_xc= xc;
-    x_and_coeff *parent_xc= parent ? parent->x_coeff : NULL;
-    x_and_coeff *prev_parent_xc= parent_xc;
-
-    runs= get_symbol2(&s->c, b->state[30], 0);
-    if(runs-- > 0) run= get_symbol2(&s->c, b->state[1], 3);
-    else           run= INT_MAX;
-
-    for(y=0; y<h; y++){
-        int v=0;
-        int lt=0, t=0, rt=0;
-
-        if(y && prev_xc->x == 0){
-            rt= prev_xc->coeff;
-        }
-        for(x=0; x<w; x++){
-            int p=0;
-            const int l= v;
-
-            lt= t; t= rt;
-
-            if(y){
-                if(prev_xc->x <= x)
-                    prev_xc++;
-                if(prev_xc->x == x + 1)
-                    rt= prev_xc->coeff;
-                else
-                    rt=0;
-            }
-            if(parent_xc){
-                if(x>>1 > parent_xc->x){
-                    parent_xc++;
-                }
-                if(x>>1 == parent_xc->x){
-                    p= parent_xc->coeff;
-                }
-            }
-            if(/*ll|*/l|lt|t|rt|p){
-                int context= av_log2(/*FFABS(ll) + */3*(l>>1) + (lt>>1) + (t&~1) + (rt>>1) + (p>>1));
 
-                v=get_rac(&s->c, &b->state[0][context]);
-                if(v){
-                    v= 2*(get_symbol2(&s->c, b->state[context + 2], context-4) + 1);
-                    v+=get_rac(&s->c, &b->state[0][16 + 1 + 3 + quant3bA[l&0xFF] + 3*quant3bA[t&0xFF]]);
+void ff_snow_inner_add_yblock(const uint8_t *obmc, const int obmc_stride, uint8_t * * block, int b_w, int b_h,
+                              int src_x, int src_y, int src_stride, slice_buffer * sb, int add, uint8_t * dst8){
+    int y, x;
+    IDWTELEM * dst;
+    for(y=0; y<b_h; y++){
+        //FIXME ugly misuse of obmc_stride
+        const uint8_t *obmc1= obmc + y*obmc_stride;
+        const uint8_t *obmc2= obmc1+ (obmc_stride>>1);
+        const uint8_t *obmc3= obmc1+ obmc_stride*(obmc_stride>>1);
+        const uint8_t *obmc4= obmc3+ (obmc_stride>>1);
+        dst = slice_buffer_get_line(sb, src_y + y);
+        for(x=0; x<b_w; x++){
+            int v=   obmc1[x] * block[3][x + y*src_stride]
+                    +obmc2[x] * block[2][x + y*src_stride]
+                    +obmc3[x] * block[1][x + y*src_stride]
+                    +obmc4[x] * block[0][x + y*src_stride];
 
-                    xc->x=x;
-                    (xc++)->coeff= v;
-                }
-            }else{
-                if(!run){
-                    if(runs-- > 0) run= get_symbol2(&s->c, b->state[1], 3);
-                    else           run= INT_MAX;
-                    v= 2*(get_symbol2(&s->c, b->state[0 + 2], 0-4) + 1);
-                    v+=get_rac(&s->c, &b->state[0][16 + 1 + 3]);
-
-                    xc->x=x;
-                    (xc++)->coeff= v;
-                }else{
-                    int max_run;
-                    run--;
-                    v=0;
-
-                    if(y) max_run= FFMIN(run, prev_xc->x - x - 2);
-                    else  max_run= FFMIN(run, w-x-1);
-                    if(parent_xc)
-                        max_run= FFMIN(max_run, 2*parent_xc->x - x - 1);
-                    x+= max_run;
-                    run-= max_run;
-                }
+            v <<= 8 - LOG2_OBMC_MAX;
+            if(FRAC_BITS != 8){
+                v >>= 8 - FRAC_BITS;
             }
-        }
-        (xc++)->x= w+1; //end marker
-        prev_xc= prev2_xc;
-        prev2_xc= xc;
-
-        if(parent_xc){
-            if(y&1){
-                while(parent_xc->x != parent->width+1)
-                    parent_xc++;
-                parent_xc++;
-                prev_parent_xc= parent_xc;
+            if(add){
+                v += dst[x + src_x];
+                v = (v + (1<<(FRAC_BITS-1))) >> FRAC_BITS;
+                if(v&(~255)) v= ~(v>>31);
+                dst8[x + y*src_stride] = v;
             }else{
-                parent_xc= prev_parent_xc;
+                dst[x + src_x] -= v;
             }
         }
     }
-
-    (xc++)->x= w+1; //end marker
-}
-
-static inline void decode_subband_slice_buffered(SnowContext *s, SubBand *b, slice_buffer * sb, int start_y, int h, int save_state[1]){
-    const int w= b->width;
-    int y;
-    const int qlog= av_clip(s->qlog + b->qlog, 0, QROOT*16);
-    int qmul= qexp[qlog&(QROOT-1)]<<(qlog>>QSHIFT);
-    int qadd= (s->qbias*qmul)>>QBIAS_SHIFT;
-    int new_index = 0;
-
-    if(b->ibuf == s->spatial_idwt_buffer || s->qlog == LOSSLESS_QLOG){
-        qadd= 0;
-        qmul= 1<<QEXPSHIFT;
-    }
-
-    /* If we are on the second or later slice, restore our index. */
-    if (start_y != 0)
-        new_index = save_state[0];
-
-
-    for(y=start_y; y<h; y++){
-        int x = 0;
-        int v;
-        IDWTELEM * line = slice_buffer_get_line(sb, y * b->stride_line + b->buf_y_offset) + b->buf_x_offset;
-        memset(line, 0, b->width*sizeof(IDWTELEM));
-        v = b->x_coeff[new_index].coeff;
-        x = b->x_coeff[new_index++].x;
-        while(x < w){
-            register int t= ( (v>>1)*qmul + qadd)>>QEXPSHIFT;
-            register int u= -(v&1);
-            line[x] = (t^u) - u;
-
-            v = b->x_coeff[new_index].coeff;
-            x = b->x_coeff[new_index++].x;
-        }
-    }
-
-    /* Save our variables for the next slice. */
-    save_state[0] = new_index;
-
-    return;
 }
 
-static void reset_contexts(SnowContext *s){ //FIXME better initial contexts
+void ff_snow_reset_contexts(SnowContext *s){ //FIXME better initial contexts
     int plane_index, level, orientation;
 
     for(plane_index=0; plane_index<3; plane_index++){
@@ -512,7 +82,7 @@ static void reset_contexts(SnowContext *s){ //FIXME better initial contexts
     memset(s->block_state, MID_STATE, sizeof(s->block_state));
 }
 
-static int alloc_blocks(SnowContext *s){
+int ff_snow_alloc_blocks(SnowContext *s){
     int w= -((-s->avctx->width )>>LOG2_MB_SIZE);
     int h= -((-s->avctx->height)>>LOG2_MB_SIZE);
 
@@ -524,129 +94,15 @@ static int alloc_blocks(SnowContext *s){
     return 0;
 }
 
-static inline void set_blocks(SnowContext *s, int level, int x, int y, int l, int cb, int cr, int mx, int my, int ref, int type){
-    const int w= s->b_width << s->block_max_depth;
-    const int rem_depth= s->block_max_depth - level;
-    const int index= (x + y*w) << rem_depth;
-    const int block_w= 1<<rem_depth;
-    BlockNode block;
-    int i,j;
-
-    block.color[0]= l;
-    block.color[1]= cb;
-    block.color[2]= cr;
-    block.mx= mx;
-    block.my= my;
-    block.ref= ref;
-    block.type= type;
-    block.level= level;
-
-    for(j=0; j<block_w; j++){
-        for(i=0; i<block_w; i++){
-            s->block[index + i + j*w]= block;
-        }
-    }
-}
-
-static inline void init_ref(MotionEstContext *c, uint8_t *src[3], uint8_t *ref[3], uint8_t *ref2[3], int x, int y, int ref_index){
-    const int offset[3]= {
-          y*c->  stride + x,
-        ((y*c->uvstride + x)>>1),
-        ((y*c->uvstride + x)>>1),
-    };
+static void init_qexp(void){
     int i;
-    for(i=0; i<3; i++){
-        c->src[0][i]= src [i];
-        c->ref[0][i]= ref [i] + offset[i];
-    }
-    assert(!ref_index);
-}
-
-static inline void pred_mv(SnowContext *s, int *mx, int *my, int ref,
-                           const BlockNode *left, const BlockNode *top, const BlockNode *tr){
-    if(s->ref_frames == 1){
-        *mx = mid_pred(left->mx, top->mx, tr->mx);
-        *my = mid_pred(left->my, top->my, tr->my);
-    }else{
-        const int *scale = scale_mv_ref[ref];
-        *mx = mid_pred((left->mx * scale[left->ref] + 128) >>8,
-                       (top ->mx * scale[top ->ref] + 128) >>8,
-                       (tr  ->mx * scale[tr  ->ref] + 128) >>8);
-        *my = mid_pred((left->my * scale[left->ref] + 128) >>8,
-                       (top ->my * scale[top ->ref] + 128) >>8,
-                       (tr  ->my * scale[tr  ->ref] + 128) >>8);
-    }
-}
-
-static av_always_inline int same_block(BlockNode *a, BlockNode *b){
-    if((a->type&BLOCK_INTRA) && (b->type&BLOCK_INTRA)){
-        return !((a->color[0] - b->color[0]) | (a->color[1] - b->color[1]) | (a->color[2] - b->color[2]));
-    }else{
-        return !((a->mx - b->mx) | (a->my - b->my) | (a->ref - b->ref) | ((a->type ^ b->type)&BLOCK_INTRA));
-    }
-}
-
-static void decode_q_branch(SnowContext *s, int level, int x, int y){
-    const int w= s->b_width << s->block_max_depth;
-    const int rem_depth= s->block_max_depth - level;
-    const int index= (x + y*w) << rem_depth;
-    int trx= (x+1)<<rem_depth;
-    const BlockNode *left  = x ? &s->block[index-1] : &null_block;
-    const BlockNode *top   = y ? &s->block[index-w] : &null_block;
-    const BlockNode *tl    = y && x ? &s->block[index-w-1] : left;
-    const BlockNode *tr    = y && trx<w && ((x&1)==0 || level==0) ? &s->block[index-w+(1<<rem_depth)] : tl; //FIXME use lt
-    int s_context= 2*left->level + 2*top->level + tl->level + tr->level;
-
-    if(s->keyframe){
-        set_blocks(s, level, x, y, null_block.color[0], null_block.color[1], null_block.color[2], null_block.mx, null_block.my, null_block.ref, BLOCK_INTRA);
-        return;
-    }
-
-    if(level==s->block_max_depth || get_rac(&s->c, &s->block_state[4 + s_context])){
-        int type, mx, my;
-        int l = left->color[0];
-        int cb= left->color[1];
-        int cr= left->color[2];
-        int ref = 0;
-        int ref_context= av_log2(2*left->ref) + av_log2(2*top->ref);
-        int mx_context= av_log2(2*FFABS(left->mx - top->mx)) + 0*av_log2(2*FFABS(tr->mx - top->mx));
-        int my_context= av_log2(2*FFABS(left->my - top->my)) + 0*av_log2(2*FFABS(tr->my - top->my));
-
-        type= get_rac(&s->c, &s->block_state[1 + left->type + top->type]) ? BLOCK_INTRA : 0;
-
-        if(type){
-            pred_mv(s, &mx, &my, 0, left, top, tr);
-            l += get_symbol(&s->c, &s->block_state[32], 1);
-            cb+= get_symbol(&s->c, &s->block_state[64], 1);
-            cr+= get_symbol(&s->c, &s->block_state[96], 1);
-        }else{
-            if(s->ref_frames > 1)
-                ref= get_symbol(&s->c, &s->block_state[128 + 1024 + 32*ref_context], 0);
-            pred_mv(s, &mx, &my, ref, left, top, tr);
-            mx+= get_symbol(&s->c, &s->block_state[128 + 32*(mx_context + 16*!!ref)], 1);
-            my+= get_symbol(&s->c, &s->block_state[128 + 32*(my_context + 16*!!ref)], 1);
-        }
-        set_blocks(s, level, x, y, l, cb, cr, mx, my, ref, type);
-    }else{
-        decode_q_branch(s, level+1, 2*x+0, 2*y+0);
-        decode_q_branch(s, level+1, 2*x+1, 2*y+0);
-        decode_q_branch(s, level+1, 2*x+0, 2*y+1);
-        decode_q_branch(s, level+1, 2*x+1, 2*y+1);
-    }
-}
-
-static void decode_blocks(SnowContext *s){
-    int x, y;
-    int w= s->b_width;
-    int h= s->b_height;
+    double v=128;
 
-    for(y=0; y<h; y++){
-        for(x=0; x<w; x++){
-            decode_q_branch(s, 0, x, y);
-        }
+    for(i=0; i<QROOT; i++){
+        qexp[i]= lrintf(v);
+        v *= pow(2, 1.0 / QROOT);
     }
 }
-
 static void mc_block(Plane *p, uint8_t *dst, const uint8_t *src, int stride, int b_w, int b_h, int dx, int dy){
     static const uint8_t weight[64]={
     8,7,6,5,4,3,2,1,
@@ -831,22 +287,7 @@ static void mc_block(Plane *p, uint8_t *dst, const uint8_t *src, int stride, int
     }
 }
 
-#define mca(dx,dy,b_w)\
-static void mc_block_hpel ## dx ## dy ## b_w(uint8_t *dst, const uint8_t *src, int stride, int h){\
-    assert(h==b_w);\
-    mc_block(NULL, dst, src-(HTAPS_MAX/2-1)-(HTAPS_MAX/2-1)*stride, stride, b_w, b_w, dx, dy);\
-}
-
-mca( 0, 0,16)
-mca( 8, 0,16)
-mca( 0, 8,16)
-mca( 8, 8,16)
-mca( 0, 0,8)
-mca( 8, 0,8)
-mca( 0, 8,8)
-mca( 8, 8,8)
-
-static void pred_block(SnowContext *s, uint8_t *dst, uint8_t *tmp, int stride, int sx, int sy, int b_w, int b_h, BlockNode *block, int plane_index, int w, int h){
+void ff_snow_pred_block(SnowContext *s, uint8_t *dst, uint8_t *tmp, int stride, int sx, int sy, int b_w, int b_h, BlockNode *block, int plane_index, int w, int h){
     if(block->type & BLOCK_INTRA){
         int x, y;
         const int color = block->color[plane_index];
@@ -926,503 +367,79 @@ static void pred_block(SnowContext *s, uint8_t *dst, uint8_t *tmp, int stride, i
     }
 }
 
-void ff_snow_inner_add_yblock(const uint8_t *obmc, const int obmc_stride, uint8_t * * block, int b_w, int b_h,
-                              int src_x, int src_y, int src_stride, slice_buffer * sb, int add, uint8_t * dst8){
-    int y, x;
-    IDWTELEM * dst;
-    for(y=0; y<b_h; y++){
-        //FIXME ugly misuse of obmc_stride
-        const uint8_t *obmc1= obmc + y*obmc_stride;
-        const uint8_t *obmc2= obmc1+ (obmc_stride>>1);
-        const uint8_t *obmc3= obmc1+ obmc_stride*(obmc_stride>>1);
-        const uint8_t *obmc4= obmc3+ (obmc_stride>>1);
-        dst = slice_buffer_get_line(sb, src_y + y);
-        for(x=0; x<b_w; x++){
-            int v=   obmc1[x] * block[3][x + y*src_stride]
-                    +obmc2[x] * block[2][x + y*src_stride]
-                    +obmc3[x] * block[1][x + y*src_stride]
-                    +obmc4[x] * block[0][x + y*src_stride];
-
-            v <<= 8 - LOG2_OBMC_MAX;
-            if(FRAC_BITS != 8){
-                v >>= 8 - FRAC_BITS;
-            }
-            if(add){
-                v += dst[x + src_x];
-                v = (v + (1<<(FRAC_BITS-1))) >> FRAC_BITS;
-                if(v&(~255)) v= ~(v>>31);
-                dst8[x + y*src_stride] = v;
-            }else{
-                dst[x + src_x] -= v;
-            }
-        }
-    }
+#define mca(dx,dy,b_w)\
+static void mc_block_hpel ## dx ## dy ## b_w(uint8_t *dst, const uint8_t *src, int stride, int h){\
+    assert(h==b_w);\
+    mc_block(NULL, dst, src-(HTAPS_MAX/2-1)-(HTAPS_MAX/2-1)*stride, stride, b_w, b_w, dx, dy);\
 }
 
-//FIXME name cleanup (b_w, block_w, b_width stuff)
-static av_always_inline void add_yblock(SnowContext *s, int sliced, slice_buffer *sb, IDWTELEM *dst, uint8_t *dst8, const uint8_t *obmc, int src_x, int src_y, int b_w, int b_h, int w, int h, int dst_stride, int src_stride, int obmc_stride, int b_x, int b_y, int add, int offset_dst, int plane_index){
-    const int b_width = s->b_width  << s->block_max_depth;
-    const int b_height= s->b_height << s->block_max_depth;
-    const int b_stride= b_width;
-    BlockNode *lt= &s->block[b_x + b_y*b_stride];
-    BlockNode *rt= lt+1;
-    BlockNode *lb= lt+b_stride;
-    BlockNode *rb= lb+1;
-    uint8_t *block[4];
-    int tmp_step= src_stride >= 7*MB_SIZE ? MB_SIZE : MB_SIZE*src_stride;
-    uint8_t *tmp = s->scratchbuf;
-    uint8_t *ptmp;
-    int x,y;
-
-    if(b_x<0){
-        lt= rt;
-        lb= rb;
-    }else if(b_x + 1 >= b_width){
-        rt= lt;
-        rb= lb;
-    }
-    if(b_y<0){
-        lt= lb;
-        rt= rb;
-    }else if(b_y + 1 >= b_height){
-        lb= lt;
-        rb= rt;
-    }
+mca( 0, 0,16)
+mca( 8, 0,16)
+mca( 0, 8,16)
+mca( 8, 8,16)
+mca( 0, 0,8)
+mca( 8, 0,8)
+mca( 0, 8,8)
+mca( 8, 8,8)
 
-    if(src_x<0){ //FIXME merge with prev & always round internal width up to *16
-        obmc -= src_x;
-        b_w += src_x;
-        if(!sliced && !offset_dst)
-            dst -= src_x;
-        src_x=0;
-    }else if(src_x + b_w > w){
-        b_w = w - src_x;
-    }
-    if(src_y<0){
-        obmc -= src_y*obmc_stride;
-        b_h += src_y;
-        if(!sliced && !offset_dst)
-            dst -= src_y*dst_stride;
-        src_y=0;
-    }else if(src_y + b_h> h){
-        b_h = h - src_y;
-    }
+av_cold int ff_snow_common_init(AVCodecContext *avctx){
+    SnowContext *s = avctx->priv_data;
+    int width, height;
+    int i, j;
 
-    if(b_w<=0 || b_h<=0) return;
+    s->avctx= avctx;
+    s->max_ref_frames=1; //just make sure its not an invalid value in case of no initial keyframe
 
-    assert(src_stride > 2*MB_SIZE + 5);
+    dsputil_init(&s->dsp, avctx);
+    ff_dwt_init(&s->dwt);
 
-    if(!sliced && offset_dst)
-        dst += src_x + src_y*dst_stride;
-    dst8+= src_x + src_y*src_stride;
-//    src += src_x + src_y*src_stride;
+#define mcf(dx,dy)\
+    s->dsp.put_qpel_pixels_tab       [0][dy+dx/4]=\
+    s->dsp.put_no_rnd_qpel_pixels_tab[0][dy+dx/4]=\
+        s->dsp.put_h264_qpel_pixels_tab[0][dy+dx/4];\
+    s->dsp.put_qpel_pixels_tab       [1][dy+dx/4]=\
+    s->dsp.put_no_rnd_qpel_pixels_tab[1][dy+dx/4]=\
+        s->dsp.put_h264_qpel_pixels_tab[1][dy+dx/4];
 
-    ptmp= tmp + 3*tmp_step;
-    block[0]= ptmp;
-    ptmp+=tmp_step;
-    pred_block(s, block[0], tmp, src_stride, src_x, src_y, b_w, b_h, lt, plane_index, w, h);
+    mcf( 0, 0)
+    mcf( 4, 0)
+    mcf( 8, 0)
+    mcf(12, 0)
+    mcf( 0, 4)
+    mcf( 4, 4)
+    mcf( 8, 4)
+    mcf(12, 4)
+    mcf( 0, 8)
+    mcf( 4, 8)
+    mcf( 8, 8)
+    mcf(12, 8)
+    mcf( 0,12)
+    mcf( 4,12)
+    mcf( 8,12)
+    mcf(12,12)
 
-    if(same_block(lt, rt)){
-        block[1]= block[0];
-    }else{
-        block[1]= ptmp;
-        ptmp+=tmp_step;
-        pred_block(s, block[1], tmp, src_stride, src_x, src_y, b_w, b_h, rt, plane_index, w, h);
-    }
+#define mcfh(dx,dy)\
+    s->dsp.put_pixels_tab       [0][dy/4+dx/8]=\
+    s->dsp.put_no_rnd_pixels_tab[0][dy/4+dx/8]=\
+        mc_block_hpel ## dx ## dy ## 16;\
+    s->dsp.put_pixels_tab       [1][dy/4+dx/8]=\
+    s->dsp.put_no_rnd_pixels_tab[1][dy/4+dx/8]=\
+        mc_block_hpel ## dx ## dy ## 8;
 
-    if(same_block(lt, lb)){
-        block[2]= block[0];
-    }else if(same_block(rt, lb)){
-        block[2]= block[1];
-    }else{
-        block[2]= ptmp;
-        ptmp+=tmp_step;
-        pred_block(s, block[2], tmp, src_stride, src_x, src_y, b_w, b_h, lb, plane_index, w, h);
-    }
+    mcfh(0, 0)
+    mcfh(8, 0)
+    mcfh(0, 8)
+    mcfh(8, 8)
 
-    if(same_block(lt, rb) ){
-        block[3]= block[0];
-    }else if(same_block(rt, rb)){
-        block[3]= block[1];
-    }else if(same_block(lb, rb)){
-        block[3]= block[2];
-    }else{
-        block[3]= ptmp;
-        pred_block(s, block[3], tmp, src_stride, src_x, src_y, b_w, b_h, rb, plane_index, w, h);
-    }
-    if(sliced){
-        s->dwt.inner_add_yblock(obmc, obmc_stride, block, b_w, b_h, src_x,src_y, src_stride, sb, add, dst8);
-    }else{
-        for(y=0; y<b_h; y++){
-            //FIXME ugly misuse of obmc_stride
-            const uint8_t *obmc1= obmc + y*obmc_stride;
-            const uint8_t *obmc2= obmc1+ (obmc_stride>>1);
-            const uint8_t *obmc3= obmc1+ obmc_stride*(obmc_stride>>1);
-            const uint8_t *obmc4= obmc3+ (obmc_stride>>1);
-            for(x=0; x<b_w; x++){
-                int v=   obmc1[x] * block[3][x + y*src_stride]
-                        +obmc2[x] * block[2][x + y*src_stride]
-                        +obmc3[x] * block[1][x + y*src_stride]
-                        +obmc4[x] * block[0][x + y*src_stride];
-
-                v <<= 8 - LOG2_OBMC_MAX;
-                if(FRAC_BITS != 8){
-                    v >>= 8 - FRAC_BITS;
-                }
-                if(add){
-                    v += dst[x + y*dst_stride];
-                    v = (v + (1<<(FRAC_BITS-1))) >> FRAC_BITS;
-                    if(v&(~255)) v= ~(v>>31);
-                    dst8[x + y*src_stride] = v;
-                }else{
-                    dst[x + y*dst_stride] -= v;
-                }
-            }
-        }
-    }
-}
+    init_qexp();
 
-static av_always_inline void predict_slice_buffered(SnowContext *s, slice_buffer * sb, IDWTELEM * old_buffer, int plane_index, int add, int mb_y){
-    Plane *p= &s->plane[plane_index];
-    const int mb_w= s->b_width  << s->block_max_depth;
-    const int mb_h= s->b_height << s->block_max_depth;
-    int x, y, mb_x;
-    int block_size = MB_SIZE >> s->block_max_depth;
-    int block_w    = plane_index ? block_size/2 : block_size;
-    const uint8_t *obmc  = plane_index ? obmc_tab[s->block_max_depth+1] : obmc_tab[s->block_max_depth];
-    int obmc_stride= plane_index ? block_size : 2*block_size;
-    int ref_stride= s->current_picture.linesize[plane_index];
-    uint8_t *dst8= s->current_picture.data[plane_index];
-    int w= p->width;
-    int h= p->height;
-
-    if(s->keyframe || (s->avctx->debug&512)){
-        if(mb_y==mb_h)
-            return;
-
-        if(add){
-            for(y=block_w*mb_y; y<FFMIN(h,block_w*(mb_y+1)); y++){
-//                DWTELEM * line = slice_buffer_get_line(sb, y);
-                IDWTELEM * line = sb->line[y];
-                for(x=0; x<w; x++){
-//                    int v= buf[x + y*w] + (128<<FRAC_BITS) + (1<<(FRAC_BITS-1));
-                    int v= line[x] + (128<<FRAC_BITS) + (1<<(FRAC_BITS-1));
-                    v >>= FRAC_BITS;
-                    if(v&(~255)) v= ~(v>>31);
-                    dst8[x + y*ref_stride]= v;
-                }
-            }
-        }else{
-            for(y=block_w*mb_y; y<FFMIN(h,block_w*(mb_y+1)); y++){
-//                DWTELEM * line = slice_buffer_get_line(sb, y);
-                IDWTELEM * line = sb->line[y];
-                for(x=0; x<w; x++){
-                    line[x] -= 128 << FRAC_BITS;
-//                    buf[x + y*w]-= 128<<FRAC_BITS;
-                }
-            }
-        }
+//    dec += FFMAX(s->chroma_h_shift, s->chroma_v_shift);
 
-        return;
-    }
+    width= s->avctx->width;
+    height= s->avctx->height;
 
-    for(mb_x=0; mb_x<=mb_w; mb_x++){
-        add_yblock(s, 1, sb, old_buffer, dst8, obmc,
-                   block_w*mb_x - block_w/2,
-                   block_w*mb_y - block_w/2,
-                   block_w, block_w,
-                   w, h,
-                   w, ref_stride, obmc_stride,
-                   mb_x - 1, mb_y - 1,
-                   add, 0, plane_index);
-    }
-}
-
-static av_always_inline void predict_slice(SnowContext *s, IDWTELEM *buf, int plane_index, int add, int mb_y){
-    Plane *p= &s->plane[plane_index];
-    const int mb_w= s->b_width  << s->block_max_depth;
-    const int mb_h= s->b_height << s->block_max_depth;
-    int x, y, mb_x;
-    int block_size = MB_SIZE >> s->block_max_depth;
-    int block_w    = plane_index ? block_size/2 : block_size;
-    const uint8_t *obmc  = plane_index ? obmc_tab[s->block_max_depth+1] : obmc_tab[s->block_max_depth];
-    const int obmc_stride= plane_index ? block_size : 2*block_size;
-    int ref_stride= s->current_picture.linesize[plane_index];
-    uint8_t *dst8= s->current_picture.data[plane_index];
-    int w= p->width;
-    int h= p->height;
-
-    if(s->keyframe || (s->avctx->debug&512)){
-        if(mb_y==mb_h)
-            return;
-
-        if(add){
-            for(y=block_w*mb_y; y<FFMIN(h,block_w*(mb_y+1)); y++){
-                for(x=0; x<w; x++){
-                    int v= buf[x + y*w] + (128<<FRAC_BITS) + (1<<(FRAC_BITS-1));
-                    v >>= FRAC_BITS;
-                    if(v&(~255)) v= ~(v>>31);
-                    dst8[x + y*ref_stride]= v;
-                }
-            }
-        }else{
-            for(y=block_w*mb_y; y<FFMIN(h,block_w*(mb_y+1)); y++){
-                for(x=0; x<w; x++){
-                    buf[x + y*w]-= 128<<FRAC_BITS;
-                }
-            }
-        }
-
-        return;
-    }
-
-    for(mb_x=0; mb_x<=mb_w; mb_x++){
-        add_yblock(s, 0, NULL, buf, dst8, obmc,
-                   block_w*mb_x - block_w/2,
-                   block_w*mb_y - block_w/2,
-                   block_w, block_w,
-                   w, h,
-                   w, ref_stride, obmc_stride,
-                   mb_x - 1, mb_y - 1,
-                   add, 1, plane_index);
-    }
-}
-
-static av_always_inline void predict_plane(SnowContext *s, IDWTELEM *buf, int plane_index, int add){
-    const int mb_h= s->b_height << s->block_max_depth;
-    int mb_y;
-    for(mb_y=0; mb_y<=mb_h; mb_y++)
-        predict_slice(s, buf, plane_index, add, mb_y);
-}
-
-static void dequantize_slice_buffered(SnowContext *s, slice_buffer * sb, SubBand *b, IDWTELEM *src, int stride, int start_y, int end_y){
-    const int w= b->width;
-    const int qlog= av_clip(s->qlog + b->qlog, 0, QROOT*16);
-    const int qmul= qexp[qlog&(QROOT-1)]<<(qlog>>QSHIFT);
-    const int qadd= (s->qbias*qmul)>>QBIAS_SHIFT;
-    int x,y;
-
-    if(s->qlog == LOSSLESS_QLOG) return;
-
-    for(y=start_y; y<end_y; y++){
-//        DWTELEM * line = slice_buffer_get_line_from_address(sb, src + (y * stride));
-        IDWTELEM * line = slice_buffer_get_line(sb, (y * b->stride_line) + b->buf_y_offset) + b->buf_x_offset;
-        for(x=0; x<w; x++){
-            int i= line[x];
-            if(i<0){
-                line[x]= -((-i*qmul + qadd)>>(QEXPSHIFT)); //FIXME try different bias
-            }else if(i>0){
-                line[x]=  (( i*qmul + qadd)>>(QEXPSHIFT));
-            }
-        }
-    }
-}
-
-static void correlate_slice_buffered(SnowContext *s, slice_buffer * sb, SubBand *b, IDWTELEM *src, int stride, int inverse, int use_median, int start_y, int end_y){
-    const int w= b->width;
-    int x,y;
-
-    IDWTELEM * line=0; // silence silly "could be used without having been initialized" warning
-    IDWTELEM * prev;
-
-    if (start_y != 0)
-        line = slice_buffer_get_line(sb, ((start_y - 1) * b->stride_line) + b->buf_y_offset) + b->buf_x_offset;
-
-    for(y=start_y; y<end_y; y++){
-        prev = line;
-//        line = slice_buffer_get_line_from_address(sb, src + (y * stride));
-        line = slice_buffer_get_line(sb, (y * b->stride_line) + b->buf_y_offset) + b->buf_x_offset;
-        for(x=0; x<w; x++){
-            if(x){
-                if(use_median){
-                    if(y && x+1<w) line[x] += mid_pred(line[x - 1], prev[x], prev[x + 1]);
-                    else  line[x] += line[x - 1];
-                }else{
-                    if(y) line[x] += mid_pred(line[x - 1], prev[x], line[x - 1] + prev[x] - prev[x - 1]);
-                    else  line[x] += line[x - 1];
-                }
-            }else{
-                if(y) line[x] += prev[x];
-            }
-        }
-    }
-}
-
-static void decode_qlogs(SnowContext *s){
-    int plane_index, level, orientation;
-
-    for(plane_index=0; plane_index<3; plane_index++){
-        for(level=0; level<s->spatial_decomposition_count; level++){
-            for(orientation=level ? 1:0; orientation<4; orientation++){
-                int q;
-                if     (plane_index==2) q= s->plane[1].band[level][orientation].qlog;
-                else if(orientation==2) q= s->plane[plane_index].band[level][1].qlog;
-                else                    q= get_symbol(&s->c, s->header_state, 1);
-                s->plane[plane_index].band[level][orientation].qlog= q;
-            }
-        }
-    }
-}
-
-#define GET_S(dst, check) \
-    tmp= get_symbol(&s->c, s->header_state, 0);\
-    if(!(check)){\
-        av_log(s->avctx, AV_LOG_ERROR, "Error " #dst " is %d\n", tmp);\
-        return -1;\
-    }\
-    dst= tmp;
-
-static int decode_header(SnowContext *s){
-    int plane_index, tmp;
-    uint8_t kstate[32];
-
-    memset(kstate, MID_STATE, sizeof(kstate));
-
-    s->keyframe= get_rac(&s->c, kstate);
-    if(s->keyframe || s->always_reset){
-        reset_contexts(s);
-        s->spatial_decomposition_type=
-        s->qlog=
-        s->qbias=
-        s->mv_scale=
-        s->block_max_depth= 0;
-    }
-    if(s->keyframe){
-        GET_S(s->version, tmp <= 0U)
-        s->always_reset= get_rac(&s->c, s->header_state);
-        s->temporal_decomposition_type= get_symbol(&s->c, s->header_state, 0);
-        s->temporal_decomposition_count= get_symbol(&s->c, s->header_state, 0);
-        GET_S(s->spatial_decomposition_count, 0 < tmp && tmp <= MAX_DECOMPOSITIONS)
-        s->colorspace_type= get_symbol(&s->c, s->header_state, 0);
-        s->chroma_h_shift= get_symbol(&s->c, s->header_state, 0);
-        s->chroma_v_shift= get_symbol(&s->c, s->header_state, 0);
-        s->spatial_scalability= get_rac(&s->c, s->header_state);
-//        s->rate_scalability= get_rac(&s->c, s->header_state);
-        GET_S(s->max_ref_frames, tmp < (unsigned)MAX_REF_FRAMES)
-        s->max_ref_frames++;
-
-        decode_qlogs(s);
-    }
-
-    if(!s->keyframe){
-        if(get_rac(&s->c, s->header_state)){
-            for(plane_index=0; plane_index<2; plane_index++){
-                int htaps, i, sum=0;
-                Plane *p= &s->plane[plane_index];
-                p->diag_mc= get_rac(&s->c, s->header_state);
-                htaps= get_symbol(&s->c, s->header_state, 0)*2 + 2;
-                if((unsigned)htaps > HTAPS_MAX || htaps==0)
-                    return -1;
-                p->htaps= htaps;
-                for(i= htaps/2; i; i--){
-                    p->hcoeff[i]= get_symbol(&s->c, s->header_state, 0) * (1-2*(i&1));
-                    sum += p->hcoeff[i];
-                }
-                p->hcoeff[0]= 32-sum;
-            }
-            s->plane[2].diag_mc= s->plane[1].diag_mc;
-            s->plane[2].htaps  = s->plane[1].htaps;
-            memcpy(s->plane[2].hcoeff, s->plane[1].hcoeff, sizeof(s->plane[1].hcoeff));
-        }
-        if(get_rac(&s->c, s->header_state)){
-            GET_S(s->spatial_decomposition_count, 0 < tmp && tmp <= MAX_DECOMPOSITIONS)
-            decode_qlogs(s);
-        }
-    }
-
-    s->spatial_decomposition_type+= get_symbol(&s->c, s->header_state, 1);
-    if(s->spatial_decomposition_type > 1U){
-        av_log(s->avctx, AV_LOG_ERROR, "spatial_decomposition_type %d not supported", s->spatial_decomposition_type);
-        return -1;
-    }
-    if(FFMIN(s->avctx-> width>>s->chroma_h_shift,
-             s->avctx->height>>s->chroma_v_shift) >> (s->spatial_decomposition_count-1) <= 0){
-        av_log(s->avctx, AV_LOG_ERROR, "spatial_decomposition_count %d too large for size", s->spatial_decomposition_count);
-        return -1;
-    }
-
-    s->qlog           += get_symbol(&s->c, s->header_state, 1);
-    s->mv_scale       += get_symbol(&s->c, s->header_state, 1);
-    s->qbias          += get_symbol(&s->c, s->header_state, 1);
-    s->block_max_depth+= get_symbol(&s->c, s->header_state, 1);
-    if(s->block_max_depth > 1 || s->block_max_depth < 0){
-        av_log(s->avctx, AV_LOG_ERROR, "block_max_depth= %d is too large", s->block_max_depth);
-        s->block_max_depth= 0;
-        return -1;
-    }
-
-    return 0;
-}
-
-static void init_qexp(void){
-    int i;
-    double v=128;
-
-    for(i=0; i<QROOT; i++){
-        qexp[i]= lrintf(v);
-        v *= pow(2, 1.0 / QROOT);
-    }
-}
-
-static av_cold int common_init(AVCodecContext *avctx){
-    SnowContext *s = avctx->priv_data;
-    int width, height;
-    int i, j;
-
-    s->avctx= avctx;
-    s->max_ref_frames=1; //just make sure its not an invalid value in case of no initial keyframe
-
-    dsputil_init(&s->dsp, avctx);
-    ff_dwt_init(&s->dwt);
-
-#define mcf(dx,dy)\
-    s->dsp.put_qpel_pixels_tab       [0][dy+dx/4]=\
-    s->dsp.put_no_rnd_qpel_pixels_tab[0][dy+dx/4]=\
-        s->dsp.put_h264_qpel_pixels_tab[0][dy+dx/4];\
-    s->dsp.put_qpel_pixels_tab       [1][dy+dx/4]=\
-    s->dsp.put_no_rnd_qpel_pixels_tab[1][dy+dx/4]=\
-        s->dsp.put_h264_qpel_pixels_tab[1][dy+dx/4];
-
-    mcf( 0, 0)
-    mcf( 4, 0)
-    mcf( 8, 0)
-    mcf(12, 0)
-    mcf( 0, 4)
-    mcf( 4, 4)
-    mcf( 8, 4)
-    mcf(12, 4)
-    mcf( 0, 8)
-    mcf( 4, 8)
-    mcf( 8, 8)
-    mcf(12, 8)
-    mcf( 0,12)
-    mcf( 4,12)
-    mcf( 8,12)
-    mcf(12,12)
-
-#define mcfh(dx,dy)\
-    s->dsp.put_pixels_tab       [0][dy/4+dx/8]=\
-    s->dsp.put_no_rnd_pixels_tab[0][dy/4+dx/8]=\
-        mc_block_hpel ## dx ## dy ## 16;\
-    s->dsp.put_pixels_tab       [1][dy/4+dx/8]=\
-    s->dsp.put_no_rnd_pixels_tab[1][dy/4+dx/8]=\
-        mc_block_hpel ## dx ## dy ## 8;
-
-    mcfh(0, 0)
-    mcfh(8, 0)
-    mcfh(0, 8)
-    mcfh(8, 8)
-
-    if(!qexp[0])
-        init_qexp();
-
-//    dec += FFMAX(s->chroma_h_shift, s->chroma_v_shift);
-
-    width= s->avctx->width;
-    height= s->avctx->height;
-
-    s->spatial_idwt_buffer= av_mallocz(width*height*sizeof(IDWTELEM));
-    s->spatial_dwt_buffer= av_mallocz(width*height*sizeof(DWTELEM)); //FIXME this does not belong here
+    s->spatial_idwt_buffer= av_mallocz(width*height*sizeof(IDWTELEM));
+    s->spatial_dwt_buffer= av_mallocz(width*height*sizeof(DWTELEM)); //FIXME this does not belong here
 
     for(i=0; i<MAX_REF_FRAMES; i++)
         for(j=0; j<MAX_REF_FRAMES; j++)
@@ -1434,7 +451,7 @@ static av_cold int common_init(AVCodecContext *avctx){
     return 0;
 }
 
-static int common_init_after_header(AVCodecContext *avctx){
+int ff_snow_common_init_after_header(AVCodecContext *avctx) {
     SnowContext *s = avctx->priv_data;
     int plane_index, level, orientation;
 
@@ -1487,123 +504,6 @@ static int common_init_after_header(AVCodecContext *avctx){
     return 0;
 }
 
-#define QUANTIZE2 0
-
-#if QUANTIZE2==1
-#define Q2_STEP 8
-
-static void find_sse(SnowContext *s, Plane *p, int *score, int score_stride, IDWTELEM *r0, IDWTELEM *r1, int level, int orientation){
-    SubBand *b= &p->band[level][orientation];
-    int x, y;
-    int xo=0;
-    int yo=0;
-    int step= 1 << (s->spatial_decomposition_count - level);
-
-    if(orientation&1)
-        xo= step>>1;
-    if(orientation&2)
-        yo= step>>1;
-
-    //FIXME bias for nonzero ?
-    //FIXME optimize
-    memset(score, 0, sizeof(*score)*score_stride*((p->height + Q2_STEP-1)/Q2_STEP));
-    for(y=0; y<p->height; y++){
-        for(x=0; x<p->width; x++){
-            int sx= (x-xo + step/2) / step / Q2_STEP;
-            int sy= (y-yo + step/2) / step / Q2_STEP;
-            int v= r0[x + y*p->width] - r1[x + y*p->width];
-            assert(sx>=0 && sy>=0 && sx < score_stride);
-            v= ((v+8)>>4)<<4;
-            score[sx + sy*score_stride] += v*v;
-            assert(score[sx + sy*score_stride] >= 0);
-        }
-    }
-}
-
-static void dequantize_all(SnowContext *s, Plane *p, IDWTELEM *buffer, int width, int height){
-    int level, orientation;
-
-    for(level=0; level<s->spatial_decomposition_count; level++){
-        for(orientation=level ? 1 : 0; orientation<4; orientation++){
-            SubBand *b= &p->band[level][orientation];
-            IDWTELEM *dst= buffer + (b->ibuf - s->spatial_idwt_buffer);
-
-            dequantize(s, b, dst, b->stride);
-        }
-    }
-}
-
-static void dwt_quantize(SnowContext *s, Plane *p, DWTELEM *buffer, int width, int height, int stride, int type){
-    int level, orientation, ys, xs, x, y, pass;
-    IDWTELEM best_dequant[height * stride];
-    IDWTELEM idwt2_buffer[height * stride];
-    const int score_stride= (width + 10)/Q2_STEP;
-    int best_score[(width + 10)/Q2_STEP * (height + 10)/Q2_STEP]; //FIXME size
-    int score[(width + 10)/Q2_STEP * (height + 10)/Q2_STEP]; //FIXME size
-    int threshold= (s->m.lambda * s->m.lambda) >> 6;
-
-    //FIXME pass the copy cleanly ?
-
-//    memcpy(dwt_buffer, buffer, height * stride * sizeof(DWTELEM));
-    ff_spatial_dwt(buffer, width, height, stride, type, s->spatial_decomposition_count);
-
-    for(level=0; level<s->spatial_decomposition_count; level++){
-        for(orientation=level ? 1 : 0; orientation<4; orientation++){
-            SubBand *b= &p->band[level][orientation];
-            IDWTELEM *dst= best_dequant + (b->ibuf - s->spatial_idwt_buffer);
-             DWTELEM *src=       buffer + (b-> buf - s->spatial_dwt_buffer);
-            assert(src == b->buf); // code does not depend on this but it is true currently
-
-            quantize(s, b, dst, src, b->stride, s->qbias);
-        }
-    }
-    for(pass=0; pass<1; pass++){
-        if(s->qbias == 0) //keyframe
-            continue;
-        for(level=0; level<s->spatial_decomposition_count; level++){
-            for(orientation=level ? 1 : 0; orientation<4; orientation++){
-                SubBand *b= &p->band[level][orientation];
-                IDWTELEM *dst= idwt2_buffer + (b->ibuf - s->spatial_idwt_buffer);
-                IDWTELEM *best_dst= best_dequant + (b->ibuf - s->spatial_idwt_buffer);
-
-                for(ys= 0; ys<Q2_STEP; ys++){
-                    for(xs= 0; xs<Q2_STEP; xs++){
-                        memcpy(idwt2_buffer, best_dequant, height * stride * sizeof(IDWTELEM));
-                        dequantize_all(s, p, idwt2_buffer, width, height);
-                        ff_spatial_idwt(idwt2_buffer, width, height, stride, type, s->spatial_decomposition_count);
-                        find_sse(s, p, best_score, score_stride, idwt2_buffer, s->spatial_idwt_buffer, level, orientation);
-                        memcpy(idwt2_buffer, best_dequant, height * stride * sizeof(IDWTELEM));
-                        for(y=ys; y<b->height; y+= Q2_STEP){
-                            for(x=xs; x<b->width; x+= Q2_STEP){
-                                if(dst[x + y*b->stride]<0) dst[x + y*b->stride]++;
-                                if(dst[x + y*b->stride]>0) dst[x + y*b->stride]--;
-                                //FIXME try more than just --
-                            }
-                        }
-                        dequantize_all(s, p, idwt2_buffer, width, height);
-                        ff_spatial_idwt(idwt2_buffer, width, height, stride, type, s->spatial_decomposition_count);
-                        find_sse(s, p, score, score_stride, idwt2_buffer, s->spatial_idwt_buffer, level, orientation);
-                        for(y=ys; y<b->height; y+= Q2_STEP){
-                            for(x=xs; x<b->width; x+= Q2_STEP){
-                                int score_idx= x/Q2_STEP + (y/Q2_STEP)*score_stride;
-                                if(score[score_idx] <= best_score[score_idx] + threshold){
-                                    best_score[score_idx]= score[score_idx];
-                                    if(best_dst[x + y*b->stride]<0) best_dst[x + y*b->stride]++;
-                                    if(best_dst[x + y*b->stride]>0) best_dst[x + y*b->stride]--;
-                                    //FIXME copy instead
-                                }
-                            }
-                        }
-                    }
-                }
-            }
-        }
-    }
-    memcpy(s->spatial_idwt_buffer, best_dequant, height * stride * sizeof(IDWTELEM)); //FIXME work with that directly instead of copy at the end
-}
-
-#endif /* QUANTIZE2==1 */
-
 #define USE_HALFPEL_PLANE 0
 
 static void halfpel_interpol(SnowContext *s, uint8_t *halfpel[4][4], AVFrame *frame){
@@ -1648,7 +548,8 @@ static void halfpel_interpol(SnowContext *s, uint8_t *halfpel[4][4], AVFrame *fr
     }
 }
 
-static void release_buffer(AVCodecContext *avctx){
+void ff_snow_release_buffer(AVCodecContext *avctx)
+{
     SnowContext *s = avctx->priv_data;
     int i;
 
@@ -1660,7 +561,7 @@ static void release_buffer(AVCodecContext *avctx){
     }
 }
 
-static int frame_start(SnowContext *s){
+int ff_snow_frame_start(SnowContext *s){
    AVFrame tmp;
    int w= s->avctx->width; //FIXME round up to x16 ?
    int h= s->avctx->height;
@@ -1677,7 +578,7 @@ static int frame_start(SnowContext *s){
                           EDGE_WIDTH/2, EDGE_WIDTH/2, EDGE_TOP | EDGE_BOTTOM);
     }
 
-    release_buffer(s->avctx);
+    ff_snow_release_buffer(s->avctx);
 
     tmp= s->last_picture[s->max_ref_frames-1];
     memmove(s->last_picture+1, s->last_picture, (s->max_ref_frames-1)*sizeof(AVFrame));
@@ -1712,7 +613,8 @@ static int frame_start(SnowContext *s){
     return 0;
 }
 
-static av_cold void common_end(SnowContext *s){
+av_cold void ff_snow_common_end(SnowContext *s)
+{
     int plane_index, level, orientation, i;
 
     av_freep(&s->spatial_dwt_buffer);
@@ -1749,1957 +651,3 @@ static av_cold void common_end(SnowContext *s){
         s->avctx->release_buffer(s->avctx, &s->current_picture);
 }
 
-static av_cold int decode_init(AVCodecContext *avctx)
-{
-    avctx->pix_fmt= PIX_FMT_YUV420P;
-
-    common_init(avctx);
-
-    return 0;
-}
-
-static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, AVPacket *avpkt){
-    const uint8_t *buf = avpkt->data;
-    int buf_size = avpkt->size;
-    SnowContext *s = avctx->priv_data;
-    RangeCoder * const c= &s->c;
-    int bytes_read;
-    AVFrame *picture = data;
-    int level, orientation, plane_index;
-
-    ff_init_range_decoder(c, buf, buf_size);
-    ff_build_rac_states(c, 0.05*(1LL<<32), 256-8);
-
-    s->current_picture.pict_type= AV_PICTURE_TYPE_I; //FIXME I vs. P
-    if(decode_header(s)<0)
-        return -1;
-    common_init_after_header(avctx);
-
-    // realloc slice buffer for the case that spatial_decomposition_count changed
-    ff_slice_buffer_destroy(&s->sb);
-    ff_slice_buffer_init(&s->sb, s->plane[0].height, (MB_SIZE >> s->block_max_depth) + s->spatial_decomposition_count * 8 + 1, s->plane[0].width, s->spatial_idwt_buffer);
-
-    for(plane_index=0; plane_index<3; plane_index++){
-        Plane *p= &s->plane[plane_index];
-        p->fast_mc= p->diag_mc && p->htaps==6 && p->hcoeff[0]==40
-                                              && p->hcoeff[1]==-10
-                                              && p->hcoeff[2]==2;
-    }
-
-    alloc_blocks(s);
-
-    if(frame_start(s) < 0)
-        return -1;
-    //keyframe flag duplication mess FIXME
-    if(avctx->debug&FF_DEBUG_PICT_INFO)
-        av_log(avctx, AV_LOG_ERROR, "keyframe:%d qlog:%d\n", s->keyframe, s->qlog);
-
-    decode_blocks(s);
-
-    for(plane_index=0; plane_index<3; plane_index++){
-        Plane *p= &s->plane[plane_index];
-        int w= p->width;
-        int h= p->height;
-        int x, y;
-        int decode_state[MAX_DECOMPOSITIONS][4][1]; /* Stored state info for unpack_coeffs. 1 variable per instance. */
-
-        if(s->avctx->debug&2048){
-            memset(s->spatial_dwt_buffer, 0, sizeof(DWTELEM)*w*h);
-            predict_plane(s, s->spatial_idwt_buffer, plane_index, 1);
-
-            for(y=0; y<h; y++){
-                for(x=0; x<w; x++){
-                    int v= s->current_picture.data[plane_index][y*s->current_picture.linesize[plane_index] + x];
-                    s->mconly_picture.data[plane_index][y*s->mconly_picture.linesize[plane_index] + x]= v;
-                }
-            }
-        }
-
-        {
-        for(level=0; level<s->spatial_decomposition_count; level++){
-            for(orientation=level ? 1 : 0; orientation<4; orientation++){
-                SubBand *b= &p->band[level][orientation];
-                unpack_coeffs(s, b, b->parent, orientation);
-            }
-        }
-        }
-
-        {
-        const int mb_h= s->b_height << s->block_max_depth;
-        const int block_size = MB_SIZE >> s->block_max_depth;
-        const int block_w    = plane_index ? block_size/2 : block_size;
-        int mb_y;
-        DWTCompose cs[MAX_DECOMPOSITIONS];
-        int yd=0, yq=0;
-        int y;
-        int end_y;
-
-        ff_spatial_idwt_buffered_init(cs, &s->sb, w, h, 1, s->spatial_decomposition_type, s->spatial_decomposition_count);
-        for(mb_y=0; mb_y<=mb_h; mb_y++){
-
-            int slice_starty = block_w*mb_y;
-            int slice_h = block_w*(mb_y+1);
-            if (!(s->keyframe || s->avctx->debug&512)){
-                slice_starty = FFMAX(0, slice_starty - (block_w >> 1));
-                slice_h -= (block_w >> 1);
-            }
-
-            for(level=0; level<s->spatial_decomposition_count; level++){
-                for(orientation=level ? 1 : 0; orientation<4; orientation++){
-                    SubBand *b= &p->band[level][orientation];
-                    int start_y;
-                    int end_y;
-                    int our_mb_start = mb_y;
-                    int our_mb_end = (mb_y + 1);
-                    const int extra= 3;
-                    start_y = (mb_y ? ((block_w * our_mb_start) >> (s->spatial_decomposition_count - level)) + s->spatial_decomposition_count - level + extra: 0);
-                    end_y = (((block_w * our_mb_end) >> (s->spatial_decomposition_count - level)) + s->spatial_decomposition_count - level + extra);
-                    if (!(s->keyframe || s->avctx->debug&512)){
-                        start_y = FFMAX(0, start_y - (block_w >> (1+s->spatial_decomposition_count - level)));
-                        end_y = FFMAX(0, end_y - (block_w >> (1+s->spatial_decomposition_count - level)));
-                    }
-                    start_y = FFMIN(b->height, start_y);
-                    end_y = FFMIN(b->height, end_y);
-
-                    if (start_y != end_y){
-                        if (orientation == 0){
-                            SubBand * correlate_band = &p->band[0][0];
-                            int correlate_end_y = FFMIN(b->height, end_y + 1);
-                            int correlate_start_y = FFMIN(b->height, (start_y ? start_y + 1 : 0));
-                            decode_subband_slice_buffered(s, correlate_band, &s->sb, correlate_start_y, correlate_end_y, decode_state[0][0]);
-                            correlate_slice_buffered(s, &s->sb, correlate_band, correlate_band->ibuf, correlate_band->stride, 1, 0, correlate_start_y, correlate_end_y);
-                            dequantize_slice_buffered(s, &s->sb, correlate_band, correlate_band->ibuf, correlate_band->stride, start_y, end_y);
-                        }
-                        else
-                            decode_subband_slice_buffered(s, b, &s->sb, start_y, end_y, decode_state[level][orientation]);
-                    }
-                }
-            }
-
-            for(; yd<slice_h; yd+=4){
-                ff_spatial_idwt_buffered_slice(&s->dwt, cs, &s->sb, w, h, 1, s->spatial_decomposition_type, s->spatial_decomposition_count, yd);
-            }
-
-            if(s->qlog == LOSSLESS_QLOG){
-                for(; yq<slice_h && yq<h; yq++){
-                    IDWTELEM * line = slice_buffer_get_line(&s->sb, yq);
-                    for(x=0; x<w; x++){
-                        line[x] <<= FRAC_BITS;
-                    }
-                }
-            }
-
-            predict_slice_buffered(s, &s->sb, s->spatial_idwt_buffer, plane_index, 1, mb_y);
-
-            y = FFMIN(p->height, slice_starty);
-            end_y = FFMIN(p->height, slice_h);
-            while(y < end_y)
-                ff_slice_buffer_release(&s->sb, y++);
-        }
-
-        ff_slice_buffer_flush(&s->sb);
-        }
-
-    }
-
-    emms_c();
-
-    release_buffer(avctx);
-
-    if(!(s->avctx->debug&2048))
-        *picture= s->current_picture;
-    else
-        *picture= s->mconly_picture;
-
-    *data_size = sizeof(AVFrame);
-
-    bytes_read= c->bytestream - c->bytestream_start;
-    if(bytes_read ==0) av_log(s->avctx, AV_LOG_ERROR, "error at end of frame\n"); //FIXME
-
-    return bytes_read;
-}
-
-static av_cold int decode_end(AVCodecContext *avctx)
-{
-    SnowContext *s = avctx->priv_data;
-
-    ff_slice_buffer_destroy(&s->sb);
-
-    common_end(s);
-
-    return 0;
-}
-
-AVCodec ff_snow_decoder = {
-    .name           = "snow",
-    .type           = AVMEDIA_TYPE_VIDEO,
-    .id             = CODEC_ID_SNOW,
-    .priv_data_size = sizeof(SnowContext),
-    .init           = decode_init,
-    .close          = decode_end,
-    .decode         = decode_frame,
-    .capabilities   = CODEC_CAP_DR1 /*| CODEC_CAP_DRAW_HORIZ_BAND*/,
-    .long_name = NULL_IF_CONFIG_SMALL("Snow"),
-};
-
-#if CONFIG_SNOW_ENCODER
-static av_cold int encode_init(AVCodecContext *avctx)
-{
-    SnowContext *s = avctx->priv_data;
-    int plane_index;
-
-    if(avctx->strict_std_compliance > FF_COMPLIANCE_EXPERIMENTAL){
-        av_log(avctx, AV_LOG_ERROR, "This codec is under development, files encoded with it may not be decodable with future versions!!!\n"
-               "Use vstrict=-2 / -strict -2 to use it anyway.\n");
-        return -1;
-    }
-
-    if(avctx->prediction_method == DWT_97
-       && (avctx->flags & CODEC_FLAG_QSCALE)
-       && avctx->global_quality == 0){
-        av_log(avctx, AV_LOG_ERROR, "The 9/7 wavelet is incompatible with lossless mode.\n");
-        return -1;
-    }
-
-    s->spatial_decomposition_type= avctx->prediction_method; //FIXME add decorrelator type r transform_type
-
-    s->mv_scale       = (avctx->flags & CODEC_FLAG_QPEL) ? 2 : 4;
-    s->block_max_depth= (avctx->flags & CODEC_FLAG_4MV ) ? 1 : 0;
-
-    for(plane_index=0; plane_index<3; plane_index++){
-        s->plane[plane_index].diag_mc= 1;
-        s->plane[plane_index].htaps= 6;
-        s->plane[plane_index].hcoeff[0]=  40;
-        s->plane[plane_index].hcoeff[1]= -10;
-        s->plane[plane_index].hcoeff[2]=   2;
-        s->plane[plane_index].fast_mc= 1;
-    }
-
-    common_init(avctx);
-    alloc_blocks(s);
-
-    s->version=0;
-
-    s->m.avctx   = avctx;
-    s->m.flags   = avctx->flags;
-    s->m.bit_rate= avctx->bit_rate;
-
-    s->m.me.temp      =
-    s->m.me.scratchpad= av_mallocz((avctx->width+64)*2*16*2*sizeof(uint8_t));
-    s->m.me.map       = av_mallocz(ME_MAP_SIZE*sizeof(uint32_t));
-    s->m.me.score_map = av_mallocz(ME_MAP_SIZE*sizeof(uint32_t));
-    s->m.obmc_scratchpad= av_mallocz(MB_SIZE*MB_SIZE*12*sizeof(uint32_t));
-    h263_encode_init(&s->m); //mv_penalty
-
-    s->max_ref_frames = FFMAX(FFMIN(avctx->refs, MAX_REF_FRAMES), 1);
-
-    if(avctx->flags&CODEC_FLAG_PASS1){
-        if(!avctx->stats_out)
-            avctx->stats_out = av_mallocz(256);
-    }
-    if((avctx->flags&CODEC_FLAG_PASS2) || !(avctx->flags&CODEC_FLAG_QSCALE)){
-        if(ff_rate_control_init(&s->m) < 0)
-            return -1;
-    }
-    s->pass1_rc= !(avctx->flags & (CODEC_FLAG_QSCALE|CODEC_FLAG_PASS2));
-
-    avctx->coded_frame= &s->current_picture;
-    switch(avctx->pix_fmt){
-//    case PIX_FMT_YUV444P:
-//    case PIX_FMT_YUV422P:
-    case PIX_FMT_YUV420P:
-    case PIX_FMT_GRAY8:
-//    case PIX_FMT_YUV411P:
-//    case PIX_FMT_YUV410P:
-        s->colorspace_type= 0;
-        break;
-/*    case PIX_FMT_RGB32:
-        s->colorspace= 1;
-        break;*/
-    default:
-        av_log(avctx, AV_LOG_ERROR, "pixel format not supported\n");
-        return -1;
-    }
-//    avcodec_get_chroma_sub_sample(avctx->pix_fmt, &s->chroma_h_shift, &s->chroma_v_shift);
-    s->chroma_h_shift= 1;
-    s->chroma_v_shift= 1;
-
-    ff_set_cmp(&s->dsp, s->dsp.me_cmp, s->avctx->me_cmp);
-    ff_set_cmp(&s->dsp, s->dsp.me_sub_cmp, s->avctx->me_sub_cmp);
-
-    s->avctx->get_buffer(s->avctx, &s->input_picture);
-
-    if(s->avctx->me_method == ME_ITER){
-        int i;
-        int size= s->b_width * s->b_height << 2*s->block_max_depth;
-        for(i=0; i<s->max_ref_frames; i++){
-            s->ref_mvs[i]= av_mallocz(size*sizeof(int16_t[2]));
-            s->ref_scores[i]= av_mallocz(size*sizeof(uint32_t));
-        }
-    }
-
-    return 0;
-}
-
-//near copy & paste from dsputil, FIXME
-static int pix_sum(uint8_t * pix, int line_size, int w)
-{
-    int s, i, j;
-
-    s = 0;
-    for (i = 0; i < w; i++) {
-        for (j = 0; j < w; j++) {
-            s += pix[0];
-            pix ++;
-        }
-        pix += line_size - w;
-    }
-    return s;
-}
-
-//near copy & paste from dsputil, FIXME
-static int pix_norm1(uint8_t * pix, int line_size, int w)
-{
-    int s, i, j;
-    uint32_t *sq = ff_squareTbl + 256;
-
-    s = 0;
-    for (i = 0; i < w; i++) {
-        for (j = 0; j < w; j ++) {
-            s += sq[pix[0]];
-            pix ++;
-        }
-        pix += line_size - w;
-    }
-    return s;
-}
-
-//FIXME copy&paste
-#define P_LEFT P[1]
-#define P_TOP P[2]
-#define P_TOPRIGHT P[3]
-#define P_MEDIAN P[4]
-#define P_MV1 P[9]
-#define FLAG_QPEL   1 //must be 1
-
-static int encode_q_branch(SnowContext *s, int level, int x, int y){
-    uint8_t p_buffer[1024];
-    uint8_t i_buffer[1024];
-    uint8_t p_state[sizeof(s->block_state)];
-    uint8_t i_state[sizeof(s->block_state)];
-    RangeCoder pc, ic;
-    uint8_t *pbbak= s->c.bytestream;
-    uint8_t *pbbak_start= s->c.bytestream_start;
-    int score, score2, iscore, i_len, p_len, block_s, sum, base_bits;
-    const int w= s->b_width  << s->block_max_depth;
-    const int h= s->b_height << s->block_max_depth;
-    const int rem_depth= s->block_max_depth - level;
-    const int index= (x + y*w) << rem_depth;
-    const int block_w= 1<<(LOG2_MB_SIZE - level);
-    int trx= (x+1)<<rem_depth;
-    int try= (y+1)<<rem_depth;
-    const BlockNode *left  = x ? &s->block[index-1] : &null_block;
-    const BlockNode *top   = y ? &s->block[index-w] : &null_block;
-    const BlockNode *right = trx<w ? &s->block[index+1] : &null_block;
-    const BlockNode *bottom= try<h ? &s->block[index+w] : &null_block;
-    const BlockNode *tl    = y && x ? &s->block[index-w-1] : left;
-    const BlockNode *tr    = y && trx<w && ((x&1)==0 || level==0) ? &s->block[index-w+(1<<rem_depth)] : tl; //FIXME use lt
-    int pl = left->color[0];
-    int pcb= left->color[1];
-    int pcr= left->color[2];
-    int pmx, pmy;
-    int mx=0, my=0;
-    int l,cr,cb;
-    const int stride= s->current_picture.linesize[0];
-    const int uvstride= s->current_picture.linesize[1];
-    uint8_t *current_data[3]= { s->input_picture.data[0] + (x + y*  stride)*block_w,
-                                s->input_picture.data[1] + (x + y*uvstride)*block_w/2,
-                                s->input_picture.data[2] + (x + y*uvstride)*block_w/2};
-    int P[10][2];
-    int16_t last_mv[3][2];
-    int qpel= !!(s->avctx->flags & CODEC_FLAG_QPEL); //unused
-    const int shift= 1+qpel;
-    MotionEstContext *c= &s->m.me;
-    int ref_context= av_log2(2*left->ref) + av_log2(2*top->ref);
-    int mx_context= av_log2(2*FFABS(left->mx - top->mx));
-    int my_context= av_log2(2*FFABS(left->my - top->my));
-    int s_context= 2*left->level + 2*top->level + tl->level + tr->level;
-    int ref, best_ref, ref_score, ref_mx, ref_my;
-
-    assert(sizeof(s->block_state) >= 256);
-    if(s->keyframe){
-        set_blocks(s, level, x, y, pl, pcb, pcr, 0, 0, 0, BLOCK_INTRA);
-        return 0;
-    }
-
-//    clip predictors / edge ?
-
-    P_LEFT[0]= left->mx;
-    P_LEFT[1]= left->my;
-    P_TOP [0]= top->mx;
-    P_TOP [1]= top->my;
-    P_TOPRIGHT[0]= tr->mx;
-    P_TOPRIGHT[1]= tr->my;
-
-    last_mv[0][0]= s->block[index].mx;
-    last_mv[0][1]= s->block[index].my;
-    last_mv[1][0]= right->mx;
-    last_mv[1][1]= right->my;
-    last_mv[2][0]= bottom->mx;
-    last_mv[2][1]= bottom->my;
-
-    s->m.mb_stride=2;
-    s->m.mb_x=
-    s->m.mb_y= 0;
-    c->skip= 0;
-
-    assert(c->  stride ==   stride);
-    assert(c->uvstride == uvstride);
-
-    c->penalty_factor    = get_penalty_factor(s->lambda, s->lambda2, c->avctx->me_cmp);
-    c->sub_penalty_factor= get_penalty_factor(s->lambda, s->lambda2, c->avctx->me_sub_cmp);
-    c->mb_penalty_factor = get_penalty_factor(s->lambda, s->lambda2, c->avctx->mb_cmp);
-    c->current_mv_penalty= c->mv_penalty[s->m.f_code=1] + MAX_MV;
-
-    c->xmin = - x*block_w - 16+3;
-    c->ymin = - y*block_w - 16+3;
-    c->xmax = - (x+1)*block_w + (w<<(LOG2_MB_SIZE - s->block_max_depth)) + 16-3;
-    c->ymax = - (y+1)*block_w + (h<<(LOG2_MB_SIZE - s->block_max_depth)) + 16-3;
-
-    if(P_LEFT[0]     > (c->xmax<<shift)) P_LEFT[0]    = (c->xmax<<shift);
-    if(P_LEFT[1]     > (c->ymax<<shift)) P_LEFT[1]    = (c->ymax<<shift);
-    if(P_TOP[0]      > (c->xmax<<shift)) P_TOP[0]     = (c->xmax<<shift);
-    if(P_TOP[1]      > (c->ymax<<shift)) P_TOP[1]     = (c->ymax<<shift);
-    if(P_TOPRIGHT[0] < (c->xmin<<shift)) P_TOPRIGHT[0]= (c->xmin<<shift);
-    if(P_TOPRIGHT[0] > (c->xmax<<shift)) P_TOPRIGHT[0]= (c->xmax<<shift); //due to pmx no clip
-    if(P_TOPRIGHT[1] > (c->ymax<<shift)) P_TOPRIGHT[1]= (c->ymax<<shift);
-
-    P_MEDIAN[0]= mid_pred(P_LEFT[0], P_TOP[0], P_TOPRIGHT[0]);
-    P_MEDIAN[1]= mid_pred(P_LEFT[1], P_TOP[1], P_TOPRIGHT[1]);
-
-    if (!y) {
-        c->pred_x= P_LEFT[0];
-        c->pred_y= P_LEFT[1];
-    } else {
-        c->pred_x = P_MEDIAN[0];
-        c->pred_y = P_MEDIAN[1];
-    }
-
-    score= INT_MAX;
-    best_ref= 0;
-    for(ref=0; ref<s->ref_frames; ref++){
-        init_ref(c, current_data, s->last_picture[ref].data, NULL, block_w*x, block_w*y, 0);
-
-        ref_score= ff_epzs_motion_search(&s->m, &ref_mx, &ref_my, P, 0, /*ref_index*/ 0, last_mv,
-                                         (1<<16)>>shift, level-LOG2_MB_SIZE+4, block_w);
-
-        assert(ref_mx >= c->xmin);
-        assert(ref_mx <= c->xmax);
-        assert(ref_my >= c->ymin);
-        assert(ref_my <= c->ymax);
-
-        ref_score= c->sub_motion_search(&s->m, &ref_mx, &ref_my, ref_score, 0, 0, level-LOG2_MB_SIZE+4, block_w);
-        ref_score= ff_get_mb_score(&s->m, ref_mx, ref_my, 0, 0, level-LOG2_MB_SIZE+4, block_w, 0);
-        ref_score+= 2*av_log2(2*ref)*c->penalty_factor;
-        if(s->ref_mvs[ref]){
-            s->ref_mvs[ref][index][0]= ref_mx;
-            s->ref_mvs[ref][index][1]= ref_my;
-            s->ref_scores[ref][index]= ref_score;
-        }
-        if(score > ref_score){
-            score= ref_score;
-            best_ref= ref;
-            mx= ref_mx;
-            my= ref_my;
-        }
-    }
-    //FIXME if mb_cmp != SSE then intra cannot be compared currently and mb_penalty vs. lambda2
-
-  //  subpel search
-    base_bits= get_rac_count(&s->c) - 8*(s->c.bytestream - s->c.bytestream_start);
-    pc= s->c;
-    pc.bytestream_start=
-    pc.bytestream= p_buffer; //FIXME end/start? and at the other stoo
-    memcpy(p_state, s->block_state, sizeof(s->block_state));
-
-    if(level!=s->block_max_depth)
-        put_rac(&pc, &p_state[4 + s_context], 1);
-    put_rac(&pc, &p_state[1 + left->type + top->type], 0);
-    if(s->ref_frames > 1)
-        put_symbol(&pc, &p_state[128 + 1024 + 32*ref_context], best_ref, 0);
-    pred_mv(s, &pmx, &pmy, best_ref, left, top, tr);
-    put_symbol(&pc, &p_state[128 + 32*(mx_context + 16*!!best_ref)], mx - pmx, 1);
-    put_symbol(&pc, &p_state[128 + 32*(my_context + 16*!!best_ref)], my - pmy, 1);
-    p_len= pc.bytestream - pc.bytestream_start;
-    score += (s->lambda2*(get_rac_count(&pc)-base_bits))>>FF_LAMBDA_SHIFT;
-
-    block_s= block_w*block_w;
-    sum = pix_sum(current_data[0], stride, block_w);
-    l= (sum + block_s/2)/block_s;
-    iscore = pix_norm1(current_data[0], stride, block_w) - 2*l*sum + l*l*block_s;
-
-    block_s= block_w*block_w>>2;
-    sum = pix_sum(current_data[1], uvstride, block_w>>1);
-    cb= (sum + block_s/2)/block_s;
-//    iscore += pix_norm1(&current_mb[1][0], uvstride, block_w>>1) - 2*cb*sum + cb*cb*block_s;
-    sum = pix_sum(current_data[2], uvstride, block_w>>1);
-    cr= (sum + block_s/2)/block_s;
-//    iscore += pix_norm1(&current_mb[2][0], uvstride, block_w>>1) - 2*cr*sum + cr*cr*block_s;
-
-    ic= s->c;
-    ic.bytestream_start=
-    ic.bytestream= i_buffer; //FIXME end/start? and at the other stoo
-    memcpy(i_state, s->block_state, sizeof(s->block_state));
-    if(level!=s->block_max_depth)
-        put_rac(&ic, &i_state[4 + s_context], 1);
-    put_rac(&ic, &i_state[1 + left->type + top->type], 1);
-    put_symbol(&ic, &i_state[32],  l-pl , 1);
-    put_symbol(&ic, &i_state[64], cb-pcb, 1);
-    put_symbol(&ic, &i_state[96], cr-pcr, 1);
-    i_len= ic.bytestream - ic.bytestream_start;
-    iscore += (s->lambda2*(get_rac_count(&ic)-base_bits))>>FF_LAMBDA_SHIFT;
-
-//    assert(score==256*256*256*64-1);
-    assert(iscore < 255*255*256 + s->lambda2*10);
-    assert(iscore >= 0);
-    assert(l>=0 && l<=255);
-    assert(pl>=0 && pl<=255);
-
-    if(level==0){
-        int varc= iscore >> 8;
-        int vard= score >> 8;
-        if (vard <= 64 || vard < varc)
-            c->scene_change_score+= ff_sqrt(vard) - ff_sqrt(varc);
-        else
-            c->scene_change_score+= s->m.qscale;
-    }
-
-    if(level!=s->block_max_depth){
-        put_rac(&s->c, &s->block_state[4 + s_context], 0);
-        score2 = encode_q_branch(s, level+1, 2*x+0, 2*y+0);
-        score2+= encode_q_branch(s, level+1, 2*x+1, 2*y+0);
-        score2+= encode_q_branch(s, level+1, 2*x+0, 2*y+1);
-        score2+= encode_q_branch(s, level+1, 2*x+1, 2*y+1);
-        score2+= s->lambda2>>FF_LAMBDA_SHIFT; //FIXME exact split overhead
-
-        if(score2 < score && score2 < iscore)
-            return score2;
-    }
-
-    if(iscore < score){
-        pred_mv(s, &pmx, &pmy, 0, left, top, tr);
-        memcpy(pbbak, i_buffer, i_len);
-        s->c= ic;
-        s->c.bytestream_start= pbbak_start;
-        s->c.bytestream= pbbak + i_len;
-        set_blocks(s, level, x, y, l, cb, cr, pmx, pmy, 0, BLOCK_INTRA);
-        memcpy(s->block_state, i_state, sizeof(s->block_state));
-        return iscore;
-    }else{
-        memcpy(pbbak, p_buffer, p_len);
-        s->c= pc;
-        s->c.bytestream_start= pbbak_start;
-        s->c.bytestream= pbbak + p_len;
-        set_blocks(s, level, x, y, pl, pcb, pcr, mx, my, best_ref, 0);
-        memcpy(s->block_state, p_state, sizeof(s->block_state));
-        return score;
-    }
-}
-
-static void encode_q_branch2(SnowContext *s, int level, int x, int y){
-    const int w= s->b_width  << s->block_max_depth;
-    const int rem_depth= s->block_max_depth - level;
-    const int index= (x + y*w) << rem_depth;
-    int trx= (x+1)<<rem_depth;
-    BlockNode *b= &s->block[index];
-    const BlockNode *left  = x ? &s->block[index-1] : &null_block;
-    const BlockNode *top   = y ? &s->block[index-w] : &null_block;
-    const BlockNode *tl    = y && x ? &s->block[index-w-1] : left;
-    const BlockNode *tr    = y && trx<w && ((x&1)==0 || level==0) ? &s->block[index-w+(1<<rem_depth)] : tl; //FIXME use lt
-    int pl = left->color[0];
-    int pcb= left->color[1];
-    int pcr= left->color[2];
-    int pmx, pmy;
-    int ref_context= av_log2(2*left->ref) + av_log2(2*top->ref);
-    int mx_context= av_log2(2*FFABS(left->mx - top->mx)) + 16*!!b->ref;
-    int my_context= av_log2(2*FFABS(left->my - top->my)) + 16*!!b->ref;
-    int s_context= 2*left->level + 2*top->level + tl->level + tr->level;
-
-    if(s->keyframe){
-        set_blocks(s, level, x, y, pl, pcb, pcr, 0, 0, 0, BLOCK_INTRA);
-        return;
-    }
-
-    if(level!=s->block_max_depth){
-        if(same_block(b,b+1) && same_block(b,b+w) && same_block(b,b+w+1)){
-            put_rac(&s->c, &s->block_state[4 + s_context], 1);
-        }else{
-            put_rac(&s->c, &s->block_state[4 + s_context], 0);
-            encode_q_branch2(s, level+1, 2*x+0, 2*y+0);
-            encode_q_branch2(s, level+1, 2*x+1, 2*y+0);
-            encode_q_branch2(s, level+1, 2*x+0, 2*y+1);
-            encode_q_branch2(s, level+1, 2*x+1, 2*y+1);
-            return;
-        }
-    }
-    if(b->type & BLOCK_INTRA){
-        pred_mv(s, &pmx, &pmy, 0, left, top, tr);
-        put_rac(&s->c, &s->block_state[1 + (left->type&1) + (top->type&1)], 1);
-        put_symbol(&s->c, &s->block_state[32], b->color[0]-pl , 1);
-        put_symbol(&s->c, &s->block_state[64], b->color[1]-pcb, 1);
-        put_symbol(&s->c, &s->block_state[96], b->color[2]-pcr, 1);
-        set_blocks(s, level, x, y, b->color[0], b->color[1], b->color[2], pmx, pmy, 0, BLOCK_INTRA);
-    }else{
-        pred_mv(s, &pmx, &pmy, b->ref, left, top, tr);
-        put_rac(&s->c, &s->block_state[1 + (left->type&1) + (top->type&1)], 0);
-        if(s->ref_frames > 1)
-            put_symbol(&s->c, &s->block_state[128 + 1024 + 32*ref_context], b->ref, 0);
-        put_symbol(&s->c, &s->block_state[128 + 32*mx_context], b->mx - pmx, 1);
-        put_symbol(&s->c, &s->block_state[128 + 32*my_context], b->my - pmy, 1);
-        set_blocks(s, level, x, y, pl, pcb, pcr, b->mx, b->my, b->ref, 0);
-    }
-}
-
-static int get_dc(SnowContext *s, int mb_x, int mb_y, int plane_index){
-    int i, x2, y2;
-    Plane *p= &s->plane[plane_index];
-    const int block_size = MB_SIZE >> s->block_max_depth;
-    const int block_w    = plane_index ? block_size/2 : block_size;
-    const uint8_t *obmc  = plane_index ? obmc_tab[s->block_max_depth+1] : obmc_tab[s->block_max_depth];
-    const int obmc_stride= plane_index ? block_size : 2*block_size;
-    const int ref_stride= s->current_picture.linesize[plane_index];
-    uint8_t *src= s-> input_picture.data[plane_index];
-    IDWTELEM *dst= (IDWTELEM*)s->m.obmc_scratchpad + plane_index*block_size*block_size*4; //FIXME change to unsigned
-    const int b_stride = s->b_width << s->block_max_depth;
-    const int w= p->width;
-    const int h= p->height;
-    int index= mb_x + mb_y*b_stride;
-    BlockNode *b= &s->block[index];
-    BlockNode backup= *b;
-    int ab=0;
-    int aa=0;
-
-    b->type|= BLOCK_INTRA;
-    b->color[plane_index]= 0;
-    memset(dst, 0, obmc_stride*obmc_stride*sizeof(IDWTELEM));
-
-    for(i=0; i<4; i++){
-        int mb_x2= mb_x + (i &1) - 1;
-        int mb_y2= mb_y + (i>>1) - 1;
-        int x= block_w*mb_x2 + block_w/2;
-        int y= block_w*mb_y2 + block_w/2;
-
-        add_yblock(s, 0, NULL, dst + ((i&1)+(i>>1)*obmc_stride)*block_w, NULL, obmc,
-                    x, y, block_w, block_w, w, h, obmc_stride, ref_stride, obmc_stride, mb_x2, mb_y2, 0, 0, plane_index);
-
-        for(y2= FFMAX(y, 0); y2<FFMIN(h, y+block_w); y2++){
-            for(x2= FFMAX(x, 0); x2<FFMIN(w, x+block_w); x2++){
-                int index= x2-(block_w*mb_x - block_w/2) + (y2-(block_w*mb_y - block_w/2))*obmc_stride;
-                int obmc_v= obmc[index];
-                int d;
-                if(y<0) obmc_v += obmc[index + block_w*obmc_stride];
-                if(x<0) obmc_v += obmc[index + block_w];
-                if(y+block_w>h) obmc_v += obmc[index - block_w*obmc_stride];
-                if(x+block_w>w) obmc_v += obmc[index - block_w];
-                //FIXME precalculate this or simplify it somehow else
-
-                d = -dst[index] + (1<<(FRAC_BITS-1));
-                dst[index] = d;
-                ab += (src[x2 + y2*ref_stride] - (d>>FRAC_BITS)) * obmc_v;
-                aa += obmc_v * obmc_v; //FIXME precalculate this
-            }
-        }
-    }
-    *b= backup;
-
-    return av_clip(((ab<<LOG2_OBMC_MAX) + aa/2)/aa, 0, 255); //FIXME we should not need clipping
-}
-
-static inline int get_block_bits(SnowContext *s, int x, int y, int w){
-    const int b_stride = s->b_width << s->block_max_depth;
-    const int b_height = s->b_height<< s->block_max_depth;
-    int index= x + y*b_stride;
-    const BlockNode *b     = &s->block[index];
-    const BlockNode *left  = x ? &s->block[index-1] : &null_block;
-    const BlockNode *top   = y ? &s->block[index-b_stride] : &null_block;
-    const BlockNode *tl    = y && x ? &s->block[index-b_stride-1] : left;
-    const BlockNode *tr    = y && x+w<b_stride ? &s->block[index-b_stride+w] : tl;
-    int dmx, dmy;
-//  int mx_context= av_log2(2*FFABS(left->mx - top->mx));
-//  int my_context= av_log2(2*FFABS(left->my - top->my));
-
-    if(x<0 || x>=b_stride || y>=b_height)
-        return 0;
-/*
-1            0      0
-01X          1-2    1
-001XX        3-6    2-3
-0001XXX      7-14   4-7
-00001XXXX   15-30   8-15
-*/
-//FIXME try accurate rate
-//FIXME intra and inter predictors if surrounding blocks are not the same type
-    if(b->type & BLOCK_INTRA){
-        return 3+2*( av_log2(2*FFABS(left->color[0] - b->color[0]))
-                   + av_log2(2*FFABS(left->color[1] - b->color[1]))
-                   + av_log2(2*FFABS(left->color[2] - b->color[2])));
-    }else{
-        pred_mv(s, &dmx, &dmy, b->ref, left, top, tr);
-        dmx-= b->mx;
-        dmy-= b->my;
-        return 2*(1 + av_log2(2*FFABS(dmx)) //FIXME kill the 2* can be merged in lambda
-                    + av_log2(2*FFABS(dmy))
-                    + av_log2(2*b->ref));
-    }
-}
-
-static int get_block_rd(SnowContext *s, int mb_x, int mb_y, int plane_index, const uint8_t *obmc_edged){
-    Plane *p= &s->plane[plane_index];
-    const int block_size = MB_SIZE >> s->block_max_depth;
-    const int block_w    = plane_index ? block_size/2 : block_size;
-    const int obmc_stride= plane_index ? block_size : 2*block_size;
-    const int ref_stride= s->current_picture.linesize[plane_index];
-    uint8_t *dst= s->current_picture.data[plane_index];
-    uint8_t *src= s->  input_picture.data[plane_index];
-    IDWTELEM *pred= (IDWTELEM*)s->m.obmc_scratchpad + plane_index*block_size*block_size*4;
-    uint8_t *cur = s->scratchbuf;
-    uint8_t tmp[ref_stride*(2*MB_SIZE+HTAPS_MAX-1)];
-    const int b_stride = s->b_width << s->block_max_depth;
-    const int b_height = s->b_height<< s->block_max_depth;
-    const int w= p->width;
-    const int h= p->height;
-    int distortion;
-    int rate= 0;
-    const int penalty_factor= get_penalty_factor(s->lambda, s->lambda2, s->avctx->me_cmp);
-    int sx= block_w*mb_x - block_w/2;
-    int sy= block_w*mb_y - block_w/2;
-    int x0= FFMAX(0,-sx);
-    int y0= FFMAX(0,-sy);
-    int x1= FFMIN(block_w*2, w-sx);
-    int y1= FFMIN(block_w*2, h-sy);
-    int i,x,y;
-
-    pred_block(s, cur, tmp, ref_stride, sx, sy, block_w*2, block_w*2, &s->block[mb_x + mb_y*b_stride], plane_index, w, h);
-
-    for(y=y0; y<y1; y++){
-        const uint8_t *obmc1= obmc_edged + y*obmc_stride;
-        const IDWTELEM *pred1 = pred + y*obmc_stride;
-        uint8_t *cur1 = cur + y*ref_stride;
-        uint8_t *dst1 = dst + sx + (sy+y)*ref_stride;
-        for(x=x0; x<x1; x++){
-#if FRAC_BITS >= LOG2_OBMC_MAX
-            int v = (cur1[x] * obmc1[x]) << (FRAC_BITS - LOG2_OBMC_MAX);
-#else
-            int v = (cur1[x] * obmc1[x] + (1<<(LOG2_OBMC_MAX - FRAC_BITS-1))) >> (LOG2_OBMC_MAX - FRAC_BITS);
-#endif
-            v = (v + pred1[x]) >> FRAC_BITS;
-            if(v&(~255)) v= ~(v>>31);
-            dst1[x] = v;
-        }
-    }
-
-    /* copy the regions where obmc[] = (uint8_t)256 */
-    if(LOG2_OBMC_MAX == 8
-        && (mb_x == 0 || mb_x == b_stride-1)
-        && (mb_y == 0 || mb_y == b_height-1)){
-        if(mb_x == 0)
-            x1 = block_w;
-        else
-            x0 = block_w;
-        if(mb_y == 0)
-            y1 = block_w;
-        else
-            y0 = block_w;
-        for(y=y0; y<y1; y++)
-            memcpy(dst + sx+x0 + (sy+y)*ref_stride, cur + x0 + y*ref_stride, x1-x0);
-    }
-
-    if(block_w==16){
-        /* FIXME rearrange dsputil to fit 32x32 cmp functions */
-        /* FIXME check alignment of the cmp wavelet vs the encoding wavelet */
-        /* FIXME cmps overlap but do not cover the wavelet's whole support.
-         * So improving the score of one block is not strictly guaranteed
-         * to improve the score of the whole frame, thus iterative motion
-         * estimation does not always converge. */
-        if(s->avctx->me_cmp == FF_CMP_W97)
-            distortion = ff_w97_32_c(&s->m, src + sx + sy*ref_stride, dst + sx + sy*ref_stride, ref_stride, 32);
-        else if(s->avctx->me_cmp == FF_CMP_W53)
-            distortion = ff_w53_32_c(&s->m, src + sx + sy*ref_stride, dst + sx + sy*ref_stride, ref_stride, 32);
-        else{
-            distortion = 0;
-            for(i=0; i<4; i++){
-                int off = sx+16*(i&1) + (sy+16*(i>>1))*ref_stride;
-                distortion += s->dsp.me_cmp[0](&s->m, src + off, dst + off, ref_stride, 16);
-            }
-        }
-    }else{
-        assert(block_w==8);
-        distortion = s->dsp.me_cmp[0](&s->m, src + sx + sy*ref_stride, dst + sx + sy*ref_stride, ref_stride, block_w*2);
-    }
-
-    if(plane_index==0){
-        for(i=0; i<4; i++){
-/* ..RRr
- * .RXx.
- * rxx..
- */
-            rate += get_block_bits(s, mb_x + (i&1) - (i>>1), mb_y + (i>>1), 1);
-        }
-        if(mb_x == b_stride-2)
-            rate += get_block_bits(s, mb_x + 1, mb_y + 1, 1);
-    }
-    return distortion + rate*penalty_factor;
-}
-
-static int get_4block_rd(SnowContext *s, int mb_x, int mb_y, int plane_index){
-    int i, y2;
-    Plane *p= &s->plane[plane_index];
-    const int block_size = MB_SIZE >> s->block_max_depth;
-    const int block_w    = plane_index ? block_size/2 : block_size;
-    const uint8_t *obmc  = plane_index ? obmc_tab[s->block_max_depth+1] : obmc_tab[s->block_max_depth];
-    const int obmc_stride= plane_index ? block_size : 2*block_size;
-    const int ref_stride= s->current_picture.linesize[plane_index];
-    uint8_t *dst= s->current_picture.data[plane_index];
-    uint8_t *src= s-> input_picture.data[plane_index];
-    //FIXME zero_dst is const but add_yblock changes dst if add is 0 (this is never the case for dst=zero_dst
-    // const has only been removed from zero_dst to suppress a warning
-    static IDWTELEM zero_dst[4096]; //FIXME
-    const int b_stride = s->b_width << s->block_max_depth;
-    const int w= p->width;
-    const int h= p->height;
-    int distortion= 0;
-    int rate= 0;
-    const int penalty_factor= get_penalty_factor(s->lambda, s->lambda2, s->avctx->me_cmp);
-
-    for(i=0; i<9; i++){
-        int mb_x2= mb_x + (i%3) - 1;
-        int mb_y2= mb_y + (i/3) - 1;
-        int x= block_w*mb_x2 + block_w/2;
-        int y= block_w*mb_y2 + block_w/2;
-
-        add_yblock(s, 0, NULL, zero_dst, dst, obmc,
-                   x, y, block_w, block_w, w, h, /*dst_stride*/0, ref_stride, obmc_stride, mb_x2, mb_y2, 1, 1, plane_index);
-
-        //FIXME find a cleaner/simpler way to skip the outside stuff
-        for(y2= y; y2<0; y2++)
-            memcpy(dst + x + y2*ref_stride, src + x + y2*ref_stride, block_w);
-        for(y2= h; y2<y+block_w; y2++)
-            memcpy(dst + x + y2*ref_stride, src + x + y2*ref_stride, block_w);
-        if(x<0){
-            for(y2= y; y2<y+block_w; y2++)
-                memcpy(dst + x + y2*ref_stride, src + x + y2*ref_stride, -x);
-        }
-        if(x+block_w > w){
-            for(y2= y; y2<y+block_w; y2++)
-                memcpy(dst + w + y2*ref_stride, src + w + y2*ref_stride, x+block_w - w);
-        }
-
-        assert(block_w== 8 || block_w==16);
-        distortion += s->dsp.me_cmp[block_w==8](&s->m, src + x + y*ref_stride, dst + x + y*ref_stride, ref_stride, block_w);
-    }
-
-    if(plane_index==0){
-        BlockNode *b= &s->block[mb_x+mb_y*b_stride];
-        int merged= same_block(b,b+1) && same_block(b,b+b_stride) && same_block(b,b+b_stride+1);
-
-/* ..RRRr
- * .RXXx.
- * .RXXx.
- * rxxx.
- */
-        if(merged)
-            rate = get_block_bits(s, mb_x, mb_y, 2);
-        for(i=merged?4:0; i<9; i++){
-            static const int dxy[9][2] = {{0,0},{1,0},{0,1},{1,1},{2,0},{2,1},{-1,2},{0,2},{1,2}};
-            rate += get_block_bits(s, mb_x + dxy[i][0], mb_y + dxy[i][1], 1);
-        }
-    }
-    return distortion + rate*penalty_factor;
-}
-
-static int encode_subband_c0run(SnowContext *s, SubBand *b, IDWTELEM *src, IDWTELEM *parent, int stride, int orientation){
-    const int w= b->width;
-    const int h= b->height;
-    int x, y;
-
-    if(1){
-        int run=0;
-        int runs[w*h];
-        int run_index=0;
-        int max_index;
-
-        for(y=0; y<h; y++){
-            for(x=0; x<w; x++){
-                int v, p=0;
-                int /*ll=0, */l=0, lt=0, t=0, rt=0;
-                v= src[x + y*stride];
-
-                if(y){
-                    t= src[x + (y-1)*stride];
-                    if(x){
-                        lt= src[x - 1 + (y-1)*stride];
-                    }
-                    if(x + 1 < w){
-                        rt= src[x + 1 + (y-1)*stride];
-                    }
-                }
-                if(x){
-                    l= src[x - 1 + y*stride];
-                    /*if(x > 1){
-                        if(orientation==1) ll= src[y + (x-2)*stride];
-                        else               ll= src[x - 2 + y*stride];
-                    }*/
-                }
-                if(parent){
-                    int px= x>>1;
-                    int py= y>>1;
-                    if(px<b->parent->width && py<b->parent->height)
-                        p= parent[px + py*2*stride];
-                }
-                if(!(/*ll|*/l|lt|t|rt|p)){
-                    if(v){
-                        runs[run_index++]= run;
-                        run=0;
-                    }else{
-                        run++;
-                    }
-                }
-            }
-        }
-        max_index= run_index;
-        runs[run_index++]= run;
-        run_index=0;
-        run= runs[run_index++];
-
-        put_symbol2(&s->c, b->state[30], max_index, 0);
-        if(run_index <= max_index)
-            put_symbol2(&s->c, b->state[1], run, 3);
-
-        for(y=0; y<h; y++){
-            if(s->c.bytestream_end - s->c.bytestream < w*40){
-                av_log(s->avctx, AV_LOG_ERROR, "encoded frame too large\n");
-                return -1;
-            }
-            for(x=0; x<w; x++){
-                int v, p=0;
-                int /*ll=0, */l=0, lt=0, t=0, rt=0;
-                v= src[x + y*stride];
-
-                if(y){
-                    t= src[x + (y-1)*stride];
-                    if(x){
-                        lt= src[x - 1 + (y-1)*stride];
-                    }
-                    if(x + 1 < w){
-                        rt= src[x + 1 + (y-1)*stride];
-                    }
-                }
-                if(x){
-                    l= src[x - 1 + y*stride];
-                    /*if(x > 1){
-                        if(orientation==1) ll= src[y + (x-2)*stride];
-                        else               ll= src[x - 2 + y*stride];
-                    }*/
-                }
-                if(parent){
-                    int px= x>>1;
-                    int py= y>>1;
-                    if(px<b->parent->width && py<b->parent->height)
-                        p= parent[px + py*2*stride];
-                }
-                if(/*ll|*/l|lt|t|rt|p){
-                    int context= av_log2(/*FFABS(ll) + */3*FFABS(l) + FFABS(lt) + 2*FFABS(t) + FFABS(rt) + FFABS(p));
-
-                    put_rac(&s->c, &b->state[0][context], !!v);
-                }else{
-                    if(!run){
-                        run= runs[run_index++];
-
-                        if(run_index <= max_index)
-                            put_symbol2(&s->c, b->state[1], run, 3);
-                        assert(v);
-                    }else{
-                        run--;
-                        assert(!v);
-                    }
-                }
-                if(v){
-                    int context= av_log2(/*FFABS(ll) + */3*FFABS(l) + FFABS(lt) + 2*FFABS(t) + FFABS(rt) + FFABS(p));
-                    int l2= 2*FFABS(l) + (l<0);
-                    int t2= 2*FFABS(t) + (t<0);
-
-                    put_symbol2(&s->c, b->state[context + 2], FFABS(v)-1, context-4);
-                    put_rac(&s->c, &b->state[0][16 + 1 + 3 + quant3bA[l2&0xFF] + 3*quant3bA[t2&0xFF]], v<0);
-                }
-            }
-        }
-    }
-    return 0;
-}
-
-static int encode_subband(SnowContext *s, SubBand *b, IDWTELEM *src, IDWTELEM *parent, int stride, int orientation){
-//    encode_subband_qtree(s, b, src, parent, stride, orientation);
-//    encode_subband_z0run(s, b, src, parent, stride, orientation);
-    return encode_subband_c0run(s, b, src, parent, stride, orientation);
-//    encode_subband_dzr(s, b, src, parent, stride, orientation);
-}
-
-static av_always_inline int check_block(SnowContext *s, int mb_x, int mb_y, int p[3], int intra, const uint8_t *obmc_edged, int *best_rd){
-    const int b_stride= s->b_width << s->block_max_depth;
-    BlockNode *block= &s->block[mb_x + mb_y * b_stride];
-    BlockNode backup= *block;
-    int rd, index, value;
-
-    assert(mb_x>=0 && mb_y>=0);
-    assert(mb_x<b_stride);
-
-    if(intra){
-        block->color[0] = p[0];
-        block->color[1] = p[1];
-        block->color[2] = p[2];
-        block->type |= BLOCK_INTRA;
-    }else{
-        index= (p[0] + 31*p[1]) & (ME_CACHE_SIZE-1);
-        value= s->me_cache_generation + (p[0]>>10) + (p[1]<<6) + (block->ref<<12);
-        if(s->me_cache[index] == value)
-            return 0;
-        s->me_cache[index]= value;
-
-        block->mx= p[0];
-        block->my= p[1];
-        block->type &= ~BLOCK_INTRA;
-    }
-
-    rd= get_block_rd(s, mb_x, mb_y, 0, obmc_edged);
-
-//FIXME chroma
-    if(rd < *best_rd){
-        *best_rd= rd;
-        return 1;
-    }else{
-        *block= backup;
-        return 0;
-    }
-}
-
-/* special case for int[2] args we discard afterwards,
- * fixes compilation problem with gcc 2.95 */
-static av_always_inline int check_block_inter(SnowContext *s, int mb_x, int mb_y, int p0, int p1, const uint8_t *obmc_edged, int *best_rd){
-    int p[2] = {p0, p1};
-    return check_block(s, mb_x, mb_y, p, 0, obmc_edged, best_rd);
-}
-
-static av_always_inline int check_4block_inter(SnowContext *s, int mb_x, int mb_y, int p0, int p1, int ref, int *best_rd){
-    const int b_stride= s->b_width << s->block_max_depth;
-    BlockNode *block= &s->block[mb_x + mb_y * b_stride];
-    BlockNode backup[4]= {block[0], block[1], block[b_stride], block[b_stride+1]};
-    int rd, index, value;
-
-    assert(mb_x>=0 && mb_y>=0);
-    assert(mb_x<b_stride);
-    assert(((mb_x|mb_y)&1) == 0);
-
-    index= (p0 + 31*p1) & (ME_CACHE_SIZE-1);
-    value= s->me_cache_generation + (p0>>10) + (p1<<6) + (block->ref<<12);
-    if(s->me_cache[index] == value)
-        return 0;
-    s->me_cache[index]= value;
-
-    block->mx= p0;
-    block->my= p1;
-    block->ref= ref;
-    block->type &= ~BLOCK_INTRA;
-    block[1]= block[b_stride]= block[b_stride+1]= *block;
-
-    rd= get_4block_rd(s, mb_x, mb_y, 0);
-
-//FIXME chroma
-    if(rd < *best_rd){
-        *best_rd= rd;
-        return 1;
-    }else{
-        block[0]= backup[0];
-        block[1]= backup[1];
-        block[b_stride]= backup[2];
-        block[b_stride+1]= backup[3];
-        return 0;
-    }
-}
-
-static void iterative_me(SnowContext *s){
-    int pass, mb_x, mb_y;
-    const int b_width = s->b_width  << s->block_max_depth;
-    const int b_height= s->b_height << s->block_max_depth;
-    const int b_stride= b_width;
-    int color[3];
-
-    {
-        RangeCoder r = s->c;
-        uint8_t state[sizeof(s->block_state)];
-        memcpy(state, s->block_state, sizeof(s->block_state));
-        for(mb_y= 0; mb_y<s->b_height; mb_y++)
-            for(mb_x= 0; mb_x<s->b_width; mb_x++)
-                encode_q_branch(s, 0, mb_x, mb_y);
-        s->c = r;
-        memcpy(s->block_state, state, sizeof(s->block_state));
-    }
-
-    for(pass=0; pass<25; pass++){
-        int change= 0;
-
-        for(mb_y= 0; mb_y<b_height; mb_y++){
-            for(mb_x= 0; mb_x<b_width; mb_x++){
-                int dia_change, i, j, ref;
-                int best_rd= INT_MAX, ref_rd;
-                BlockNode backup, ref_b;
-                const int index= mb_x + mb_y * b_stride;
-                BlockNode *block= &s->block[index];
-                BlockNode *tb =                   mb_y            ? &s->block[index-b_stride  ] : NULL;
-                BlockNode *lb = mb_x                              ? &s->block[index         -1] : NULL;
-                BlockNode *rb = mb_x+1<b_width                    ? &s->block[index         +1] : NULL;
-                BlockNode *bb =                   mb_y+1<b_height ? &s->block[index+b_stride  ] : NULL;
-                BlockNode *tlb= mb_x           && mb_y            ? &s->block[index-b_stride-1] : NULL;
-                BlockNode *trb= mb_x+1<b_width && mb_y            ? &s->block[index-b_stride+1] : NULL;
-                BlockNode *blb= mb_x           && mb_y+1<b_height ? &s->block[index+b_stride-1] : NULL;
-                BlockNode *brb= mb_x+1<b_width && mb_y+1<b_height ? &s->block[index+b_stride+1] : NULL;
-                const int b_w= (MB_SIZE >> s->block_max_depth);
-                uint8_t obmc_edged[b_w*2][b_w*2];
-
-                if(pass && (block->type & BLOCK_OPT))
-                    continue;
-                block->type |= BLOCK_OPT;
-
-                backup= *block;
-
-                if(!s->me_cache_generation)
-                    memset(s->me_cache, 0, sizeof(s->me_cache));
-                s->me_cache_generation += 1<<22;
-
-                //FIXME precalculate
-                {
-                    int x, y;
-                    memcpy(obmc_edged, obmc_tab[s->block_max_depth], b_w*b_w*4);
-                    if(mb_x==0)
-                        for(y=0; y<b_w*2; y++)
-                            memset(obmc_edged[y], obmc_edged[y][0] + obmc_edged[y][b_w-1], b_w);
-                    if(mb_x==b_stride-1)
-                        for(y=0; y<b_w*2; y++)
-                            memset(obmc_edged[y]+b_w, obmc_edged[y][b_w] + obmc_edged[y][b_w*2-1], b_w);
-                    if(mb_y==0){
-                        for(x=0; x<b_w*2; x++)
-                            obmc_edged[0][x] += obmc_edged[b_w-1][x];
-                        for(y=1; y<b_w; y++)
-                            memcpy(obmc_edged[y], obmc_edged[0], b_w*2);
-                    }
-                    if(mb_y==b_height-1){
-                        for(x=0; x<b_w*2; x++)
-                            obmc_edged[b_w*2-1][x] += obmc_edged[b_w][x];
-                        for(y=b_w; y<b_w*2-1; y++)
-                            memcpy(obmc_edged[y], obmc_edged[b_w*2-1], b_w*2);
-                    }
-                }
-
-                //skip stuff outside the picture
-                if(mb_x==0 || mb_y==0 || mb_x==b_width-1 || mb_y==b_height-1){
-                    uint8_t *src= s->  input_picture.data[0];
-                    uint8_t *dst= s->current_picture.data[0];
-                    const int stride= s->current_picture.linesize[0];
-                    const int block_w= MB_SIZE >> s->block_max_depth;
-                    const int sx= block_w*mb_x - block_w/2;
-                    const int sy= block_w*mb_y - block_w/2;
-                    const int w= s->plane[0].width;
-                    const int h= s->plane[0].height;
-                    int y;
-
-                    for(y=sy; y<0; y++)
-                        memcpy(dst + sx + y*stride, src + sx + y*stride, block_w*2);
-                    for(y=h; y<sy+block_w*2; y++)
-                        memcpy(dst + sx + y*stride, src + sx + y*stride, block_w*2);
-                    if(sx<0){
-                        for(y=sy; y<sy+block_w*2; y++)
-                            memcpy(dst + sx + y*stride, src + sx + y*stride, -sx);
-                    }
-                    if(sx+block_w*2 > w){
-                        for(y=sy; y<sy+block_w*2; y++)
-                            memcpy(dst + w + y*stride, src + w + y*stride, sx+block_w*2 - w);
-                    }
-                }
-
-                // intra(black) = neighbors' contribution to the current block
-                for(i=0; i<3; i++)
-                    color[i]= get_dc(s, mb_x, mb_y, i);
-
-                // get previous score (cannot be cached due to OBMC)
-                if(pass > 0 && (block->type&BLOCK_INTRA)){
-                    int color0[3]= {block->color[0], block->color[1], block->color[2]};
-                    check_block(s, mb_x, mb_y, color0, 1, *obmc_edged, &best_rd);
-                }else
-                    check_block_inter(s, mb_x, mb_y, block->mx, block->my, *obmc_edged, &best_rd);
-
-                ref_b= *block;
-                ref_rd= best_rd;
-                for(ref=0; ref < s->ref_frames; ref++){
-                    int16_t (*mvr)[2]= &s->ref_mvs[ref][index];
-                    if(s->ref_scores[ref][index] > s->ref_scores[ref_b.ref][index]*3/2) //FIXME tune threshold
-                        continue;
-                    block->ref= ref;
-                    best_rd= INT_MAX;
-
-                    check_block_inter(s, mb_x, mb_y, mvr[0][0], mvr[0][1], *obmc_edged, &best_rd);
-                    check_block_inter(s, mb_x, mb_y, 0, 0, *obmc_edged, &best_rd);
-                    if(tb)
-                        check_block_inter(s, mb_x, mb_y, mvr[-b_stride][0], mvr[-b_stride][1], *obmc_edged, &best_rd);
-                    if(lb)
-                        check_block_inter(s, mb_x, mb_y, mvr[-1][0], mvr[-1][1], *obmc_edged, &best_rd);
-                    if(rb)
-                        check_block_inter(s, mb_x, mb_y, mvr[1][0], mvr[1][1], *obmc_edged, &best_rd);
-                    if(bb)
-                        check_block_inter(s, mb_x, mb_y, mvr[b_stride][0], mvr[b_stride][1], *obmc_edged, &best_rd);
-
-                    /* fullpel ME */
-                    //FIXME avoid subpel interpolation / round to nearest integer
-                    do{
-                        dia_change=0;
-                        for(i=0; i<FFMAX(s->avctx->dia_size, 1); i++){
-                            for(j=0; j<i; j++){
-                                dia_change |= check_block_inter(s, mb_x, mb_y, block->mx+4*(i-j), block->my+(4*j), *obmc_edged, &best_rd);
-                                dia_change |= check_block_inter(s, mb_x, mb_y, block->mx-4*(i-j), block->my-(4*j), *obmc_edged, &best_rd);
-                                dia_change |= check_block_inter(s, mb_x, mb_y, block->mx+4*(i-j), block->my-(4*j), *obmc_edged, &best_rd);
-                                dia_change |= check_block_inter(s, mb_x, mb_y, block->mx-4*(i-j), block->my+(4*j), *obmc_edged, &best_rd);
-                            }
-                        }
-                    }while(dia_change);
-                    /* subpel ME */
-                    do{
-                        static const int square[8][2]= {{+1, 0},{-1, 0},{ 0,+1},{ 0,-1},{+1,+1},{-1,-1},{+1,-1},{-1,+1},};
-                        dia_change=0;
-                        for(i=0; i<8; i++)
-                            dia_change |= check_block_inter(s, mb_x, mb_y, block->mx+square[i][0], block->my+square[i][1], *obmc_edged, &best_rd);
-                    }while(dia_change);
-                    //FIXME or try the standard 2 pass qpel or similar
-
-                    mvr[0][0]= block->mx;
-                    mvr[0][1]= block->my;
-                    if(ref_rd > best_rd){
-                        ref_rd= best_rd;
-                        ref_b= *block;
-                    }
-                }
-                best_rd= ref_rd;
-                *block= ref_b;
-                check_block(s, mb_x, mb_y, color, 1, *obmc_edged, &best_rd);
-                //FIXME RD style color selection
-                if(!same_block(block, &backup)){
-                    if(tb ) tb ->type &= ~BLOCK_OPT;
-                    if(lb ) lb ->type &= ~BLOCK_OPT;
-                    if(rb ) rb ->type &= ~BLOCK_OPT;
-                    if(bb ) bb ->type &= ~BLOCK_OPT;
-                    if(tlb) tlb->type &= ~BLOCK_OPT;
-                    if(trb) trb->type &= ~BLOCK_OPT;
-                    if(blb) blb->type &= ~BLOCK_OPT;
-                    if(brb) brb->type &= ~BLOCK_OPT;
-                    change ++;
-                }
-            }
-        }
-        av_log(s->avctx, AV_LOG_ERROR, "pass:%d changed:%d\n", pass, change);
-        if(!change)
-            break;
-    }
-
-    if(s->block_max_depth == 1){
-        int change= 0;
-        for(mb_y= 0; mb_y<b_height; mb_y+=2){
-            for(mb_x= 0; mb_x<b_width; mb_x+=2){
-                int i;
-                int best_rd, init_rd;
-                const int index= mb_x + mb_y * b_stride;
-                BlockNode *b[4];
-
-                b[0]= &s->block[index];
-                b[1]= b[0]+1;
-                b[2]= b[0]+b_stride;
-                b[3]= b[2]+1;
-                if(same_block(b[0], b[1]) &&
-                   same_block(b[0], b[2]) &&
-                   same_block(b[0], b[3]))
-                    continue;
-
-                if(!s->me_cache_generation)
-                    memset(s->me_cache, 0, sizeof(s->me_cache));
-                s->me_cache_generation += 1<<22;
-
-                init_rd= best_rd= get_4block_rd(s, mb_x, mb_y, 0);
-
-                //FIXME more multiref search?
-                check_4block_inter(s, mb_x, mb_y,
-                                   (b[0]->mx + b[1]->mx + b[2]->mx + b[3]->mx + 2) >> 2,
-                                   (b[0]->my + b[1]->my + b[2]->my + b[3]->my + 2) >> 2, 0, &best_rd);
-
-                for(i=0; i<4; i++)
-                    if(!(b[i]->type&BLOCK_INTRA))
-                        check_4block_inter(s, mb_x, mb_y, b[i]->mx, b[i]->my, b[i]->ref, &best_rd);
-
-                if(init_rd != best_rd)
-                    change++;
-            }
-        }
-        av_log(s->avctx, AV_LOG_ERROR, "pass:4mv changed:%d\n", change*4);
-    }
-}
-
-static void encode_blocks(SnowContext *s, int search){
-    int x, y;
-    int w= s->b_width;
-    int h= s->b_height;
-
-    if(s->avctx->me_method == ME_ITER && !s->keyframe && search)
-        iterative_me(s);
-
-    for(y=0; y<h; y++){
-        if(s->c.bytestream_end - s->c.bytestream < w*MB_SIZE*MB_SIZE*3){ //FIXME nicer limit
-            av_log(s->avctx, AV_LOG_ERROR, "encoded frame too large\n");
-            return;
-        }
-        for(x=0; x<w; x++){
-            if(s->avctx->me_method == ME_ITER || !search)
-                encode_q_branch2(s, 0, x, y);
-            else
-                encode_q_branch (s, 0, x, y);
-        }
-    }
-}
-
-static void quantize(SnowContext *s, SubBand *b, IDWTELEM *dst, DWTELEM *src, int stride, int bias){
-    const int w= b->width;
-    const int h= b->height;
-    const int qlog= av_clip(s->qlog + b->qlog, 0, QROOT*16);
-    const int qmul= qexp[qlog&(QROOT-1)]<<((qlog>>QSHIFT) + ENCODER_EXTRA_BITS);
-    int x,y, thres1, thres2;
-
-    if(s->qlog == LOSSLESS_QLOG){
-        for(y=0; y<h; y++)
-            for(x=0; x<w; x++)
-                dst[x + y*stride]= src[x + y*stride];
-        return;
-    }
-
-    bias= bias ? 0 : (3*qmul)>>3;
-    thres1= ((qmul - bias)>>QEXPSHIFT) - 1;
-    thres2= 2*thres1;
-
-    if(!bias){
-        for(y=0; y<h; y++){
-            for(x=0; x<w; x++){
-                int i= src[x + y*stride];
-
-                if((unsigned)(i+thres1) > thres2){
-                    if(i>=0){
-                        i<<= QEXPSHIFT;
-                        i/= qmul; //FIXME optimize
-                        dst[x + y*stride]=  i;
-                    }else{
-                        i= -i;
-                        i<<= QEXPSHIFT;
-                        i/= qmul; //FIXME optimize
-                        dst[x + y*stride]= -i;
-                    }
-                }else
-                    dst[x + y*stride]= 0;
-            }
-        }
-    }else{
-        for(y=0; y<h; y++){
-            for(x=0; x<w; x++){
-                int i= src[x + y*stride];
-
-                if((unsigned)(i+thres1) > thres2){
-                    if(i>=0){
-                        i<<= QEXPSHIFT;
-                        i= (i + bias) / qmul; //FIXME optimize
-                        dst[x + y*stride]=  i;
-                    }else{
-                        i= -i;
-                        i<<= QEXPSHIFT;
-                        i= (i + bias) / qmul; //FIXME optimize
-                        dst[x + y*stride]= -i;
-                    }
-                }else
-                    dst[x + y*stride]= 0;
-            }
-        }
-    }
-}
-
-static void dequantize(SnowContext *s, SubBand *b, IDWTELEM *src, int stride){
-    const int w= b->width;
-    const int h= b->height;
-    const int qlog= av_clip(s->qlog + b->qlog, 0, QROOT*16);
-    const int qmul= qexp[qlog&(QROOT-1)]<<(qlog>>QSHIFT);
-    const int qadd= (s->qbias*qmul)>>QBIAS_SHIFT;
-    int x,y;
-
-    if(s->qlog == LOSSLESS_QLOG) return;
-
-    for(y=0; y<h; y++){
-        for(x=0; x<w; x++){
-            int i= src[x + y*stride];
-            if(i<0){
-                src[x + y*stride]= -((-i*qmul + qadd)>>(QEXPSHIFT)); //FIXME try different bias
-            }else if(i>0){
-                src[x + y*stride]=  (( i*qmul + qadd)>>(QEXPSHIFT));
-            }
-        }
-    }
-}
-
-static void decorrelate(SnowContext *s, SubBand *b, IDWTELEM *src, int stride, int inverse, int use_median){
-    const int w= b->width;
-    const int h= b->height;
-    int x,y;
-
-    for(y=h-1; y>=0; y--){
-        for(x=w-1; x>=0; x--){
-            int i= x + y*stride;
-
-            if(x){
-                if(use_median){
-                    if(y && x+1<w) src[i] -= mid_pred(src[i - 1], src[i - stride], src[i - stride + 1]);
-                    else  src[i] -= src[i - 1];
-                }else{
-                    if(y) src[i] -= mid_pred(src[i - 1], src[i - stride], src[i - 1] + src[i - stride] - src[i - 1 - stride]);
-                    else  src[i] -= src[i - 1];
-                }
-            }else{
-                if(y) src[i] -= src[i - stride];
-            }
-        }
-    }
-}
-
-static void correlate(SnowContext *s, SubBand *b, IDWTELEM *src, int stride, int inverse, int use_median){
-    const int w= b->width;
-    const int h= b->height;
-    int x,y;
-
-    for(y=0; y<h; y++){
-        for(x=0; x<w; x++){
-            int i= x + y*stride;
-
-            if(x){
-                if(use_median){
-                    if(y && x+1<w) src[i] += mid_pred(src[i - 1], src[i - stride], src[i - stride + 1]);
-                    else  src[i] += src[i - 1];
-                }else{
-                    if(y) src[i] += mid_pred(src[i - 1], src[i - stride], src[i - 1] + src[i - stride] - src[i - 1 - stride]);
-                    else  src[i] += src[i - 1];
-                }
-            }else{
-                if(y) src[i] += src[i - stride];
-            }
-        }
-    }
-}
-
-static void encode_qlogs(SnowContext *s){
-    int plane_index, level, orientation;
-
-    for(plane_index=0; plane_index<2; plane_index++){
-        for(level=0; level<s->spatial_decomposition_count; level++){
-            for(orientation=level ? 1:0; orientation<4; orientation++){
-                if(orientation==2) continue;
-                put_symbol(&s->c, s->header_state, s->plane[plane_index].band[level][orientation].qlog, 1);
-            }
-        }
-    }
-}
-
-static void encode_header(SnowContext *s){
-    int plane_index, i;
-    uint8_t kstate[32];
-
-    memset(kstate, MID_STATE, sizeof(kstate));
-
-    put_rac(&s->c, kstate, s->keyframe);
-    if(s->keyframe || s->always_reset){
-        reset_contexts(s);
-        s->last_spatial_decomposition_type=
-        s->last_qlog=
-        s->last_qbias=
-        s->last_mv_scale=
-        s->last_block_max_depth= 0;
-        for(plane_index=0; plane_index<2; plane_index++){
-            Plane *p= &s->plane[plane_index];
-            p->last_htaps=0;
-            p->last_diag_mc=0;
-            memset(p->last_hcoeff, 0, sizeof(p->last_hcoeff));
-        }
-    }
-    if(s->keyframe){
-        put_symbol(&s->c, s->header_state, s->version, 0);
-        put_rac(&s->c, s->header_state, s->always_reset);
-        put_symbol(&s->c, s->header_state, s->temporal_decomposition_type, 0);
-        put_symbol(&s->c, s->header_state, s->temporal_decomposition_count, 0);
-        put_symbol(&s->c, s->header_state, s->spatial_decomposition_count, 0);
-        put_symbol(&s->c, s->header_state, s->colorspace_type, 0);
-        put_symbol(&s->c, s->header_state, s->chroma_h_shift, 0);
-        put_symbol(&s->c, s->header_state, s->chroma_v_shift, 0);
-        put_rac(&s->c, s->header_state, s->spatial_scalability);
-//        put_rac(&s->c, s->header_state, s->rate_scalability);
-        put_symbol(&s->c, s->header_state, s->max_ref_frames-1, 0);
-
-        encode_qlogs(s);
-    }
-
-    if(!s->keyframe){
-        int update_mc=0;
-        for(plane_index=0; plane_index<2; plane_index++){
-            Plane *p= &s->plane[plane_index];
-            update_mc |= p->last_htaps   != p->htaps;
-            update_mc |= p->last_diag_mc != p->diag_mc;
-            update_mc |= !!memcmp(p->last_hcoeff, p->hcoeff, sizeof(p->hcoeff));
-        }
-        put_rac(&s->c, s->header_state, update_mc);
-        if(update_mc){
-            for(plane_index=0; plane_index<2; plane_index++){
-                Plane *p= &s->plane[plane_index];
-                put_rac(&s->c, s->header_state, p->diag_mc);
-                put_symbol(&s->c, s->header_state, p->htaps/2-1, 0);
-                for(i= p->htaps/2; i; i--)
-                    put_symbol(&s->c, s->header_state, FFABS(p->hcoeff[i]), 0);
-            }
-        }
-        if(s->last_spatial_decomposition_count != s->spatial_decomposition_count){
-            put_rac(&s->c, s->header_state, 1);
-            put_symbol(&s->c, s->header_state, s->spatial_decomposition_count, 0);
-            encode_qlogs(s);
-        }else
-            put_rac(&s->c, s->header_state, 0);
-    }
-
-    put_symbol(&s->c, s->header_state, s->spatial_decomposition_type - s->last_spatial_decomposition_type, 1);
-    put_symbol(&s->c, s->header_state, s->qlog            - s->last_qlog    , 1);
-    put_symbol(&s->c, s->header_state, s->mv_scale        - s->last_mv_scale, 1);
-    put_symbol(&s->c, s->header_state, s->qbias           - s->last_qbias   , 1);
-    put_symbol(&s->c, s->header_state, s->block_max_depth - s->last_block_max_depth, 1);
-
-}
-
-static void update_last_header_values(SnowContext *s){
-    int plane_index;
-
-    if(!s->keyframe){
-        for(plane_index=0; plane_index<2; plane_index++){
-            Plane *p= &s->plane[plane_index];
-            p->last_diag_mc= p->diag_mc;
-            p->last_htaps  = p->htaps;
-            memcpy(p->last_hcoeff, p->hcoeff, sizeof(p->hcoeff));
-        }
-    }
-
-    s->last_spatial_decomposition_type  = s->spatial_decomposition_type;
-    s->last_qlog                        = s->qlog;
-    s->last_qbias                       = s->qbias;
-    s->last_mv_scale                    = s->mv_scale;
-    s->last_block_max_depth             = s->block_max_depth;
-    s->last_spatial_decomposition_count = s->spatial_decomposition_count;
-}
-
-static int qscale2qlog(int qscale){
-    return rint(QROOT*log(qscale / (float)FF_QP2LAMBDA)/log(2))
-           + 61*QROOT/8; ///< 64 > 60
-}
-
-static int ratecontrol_1pass(SnowContext *s, AVFrame *pict)
-{
-    /* Estimate the frame's complexity as a sum of weighted dwt coefficients.
-     * FIXME we know exact mv bits at this point,
-     * but ratecontrol isn't set up to include them. */
-    uint32_t coef_sum= 0;
-    int level, orientation, delta_qlog;
-
-    for(level=0; level<s->spatial_decomposition_count; level++){
-        for(orientation=level ? 1 : 0; orientation<4; orientation++){
-            SubBand *b= &s->plane[0].band[level][orientation];
-            IDWTELEM *buf= b->ibuf;
-            const int w= b->width;
-            const int h= b->height;
-            const int stride= b->stride;
-            const int qlog= av_clip(2*QROOT + b->qlog, 0, QROOT*16);
-            const int qmul= qexp[qlog&(QROOT-1)]<<(qlog>>QSHIFT);
-            const int qdiv= (1<<16)/qmul;
-            int x, y;
-            //FIXME this is ugly
-            for(y=0; y<h; y++)
-                for(x=0; x<w; x++)
-                    buf[x+y*stride]= b->buf[x+y*stride];
-            if(orientation==0)
-                decorrelate(s, b, buf, stride, 1, 0);
-            for(y=0; y<h; y++)
-                for(x=0; x<w; x++)
-                    coef_sum+= abs(buf[x+y*stride]) * qdiv >> 16;
-        }
-    }
-
-    /* ugly, ratecontrol just takes a sqrt again */
-    coef_sum = (uint64_t)coef_sum * coef_sum >> 16;
-    assert(coef_sum < INT_MAX);
-
-    if(pict->pict_type == AV_PICTURE_TYPE_I){
-        s->m.current_picture.mb_var_sum= coef_sum;
-        s->m.current_picture.mc_mb_var_sum= 0;
-    }else{
-        s->m.current_picture.mc_mb_var_sum= coef_sum;
-        s->m.current_picture.mb_var_sum= 0;
-    }
-
-    pict->quality= ff_rate_estimate_qscale(&s->m, 1);
-    if (pict->quality < 0)
-        return INT_MIN;
-    s->lambda= pict->quality * 3/2;
-    delta_qlog= qscale2qlog(pict->quality) - s->qlog;
-    s->qlog+= delta_qlog;
-    return delta_qlog;
-}
-
-static void calculate_visual_weight(SnowContext *s, Plane *p){
-    int width = p->width;
-    int height= p->height;
-    int level, orientation, x, y;
-
-    for(level=0; level<s->spatial_decomposition_count; level++){
-        for(orientation=level ? 1 : 0; orientation<4; orientation++){
-            SubBand *b= &p->band[level][orientation];
-            IDWTELEM *ibuf= b->ibuf;
-            int64_t error=0;
-
-            memset(s->spatial_idwt_buffer, 0, sizeof(*s->spatial_idwt_buffer)*width*height);
-            ibuf[b->width/2 + b->height/2*b->stride]= 256*16;
-            ff_spatial_idwt(s->spatial_idwt_buffer, width, height, width, s->spatial_decomposition_type, s->spatial_decomposition_count);
-            for(y=0; y<height; y++){
-                for(x=0; x<width; x++){
-                    int64_t d= s->spatial_idwt_buffer[x + y*width]*16;
-                    error += d*d;
-                }
-            }
-
-            b->qlog= (int)(log(352256.0/sqrt(error)) / log(pow(2.0, 1.0/QROOT))+0.5);
-        }
-    }
-}
-
-static int encode_frame(AVCodecContext *avctx, unsigned char *buf, int buf_size, void *data){
-    SnowContext *s = avctx->priv_data;
-    RangeCoder * const c= &s->c;
-    AVFrame *pict = data;
-    const int width= s->avctx->width;
-    const int height= s->avctx->height;
-    int level, orientation, plane_index, i, y;
-    uint8_t rc_header_bak[sizeof(s->header_state)];
-    uint8_t rc_block_bak[sizeof(s->block_state)];
-
-    ff_init_range_encoder(c, buf, buf_size);
-    ff_build_rac_states(c, 0.05*(1LL<<32), 256-8);
-
-    for(i=0; i<3; i++){
-        int shift= !!i;
-        for(y=0; y<(height>>shift); y++)
-            memcpy(&s->input_picture.data[i][y * s->input_picture.linesize[i]],
-                   &pict->data[i][y * pict->linesize[i]],
-                   width>>shift);
-    }
-    s->new_picture = *pict;
-
-    s->m.picture_number= avctx->frame_number;
-    if(avctx->flags&CODEC_FLAG_PASS2){
-        s->m.pict_type =
-        pict->pict_type= s->m.rc_context.entry[avctx->frame_number].new_pict_type;
-        s->keyframe= pict->pict_type==AV_PICTURE_TYPE_I;
-        if(!(avctx->flags&CODEC_FLAG_QSCALE)) {
-            pict->quality= ff_rate_estimate_qscale(&s->m, 0);
-            if (pict->quality < 0)
-                return -1;
-        }
-    }else{
-        s->keyframe= avctx->gop_size==0 || avctx->frame_number % avctx->gop_size == 0;
-        s->m.pict_type=
-        pict->pict_type= s->keyframe ? AV_PICTURE_TYPE_I : AV_PICTURE_TYPE_P;
-    }
-
-    if(s->pass1_rc && avctx->frame_number == 0)
-        pict->quality= 2*FF_QP2LAMBDA;
-    if(pict->quality){
-        s->qlog= qscale2qlog(pict->quality);
-        s->lambda = pict->quality * 3/2;
-    }
-    if(s->qlog < 0 || (!pict->quality && (avctx->flags & CODEC_FLAG_QSCALE))){
-        s->qlog= LOSSLESS_QLOG;
-        s->lambda = 0;
-    }//else keep previous frame's qlog until after motion estimation
-
-    frame_start(s);
-
-    s->m.current_picture_ptr= &s->m.current_picture;
-    s->m.last_picture.f.pts = s->m.current_picture.f.pts;
-    s->m.current_picture.f.pts = pict->pts;
-    if(pict->pict_type == AV_PICTURE_TYPE_P){
-        int block_width = (width +15)>>4;
-        int block_height= (height+15)>>4;
-        int stride= s->current_picture.linesize[0];
-
-        assert(s->current_picture.data[0]);
-        assert(s->last_picture[0].data[0]);
-
-        s->m.avctx= s->avctx;
-        s->m.current_picture.f.data[0] = s->current_picture.data[0];
-        s->m.   last_picture.f.data[0] = s->last_picture[0].data[0];
-        s->m.    new_picture.f.data[0] = s->  input_picture.data[0];
-        s->m.   last_picture_ptr= &s->m.   last_picture;
-        s->m.linesize=
-        s->m.   last_picture.f.linesize[0] =
-        s->m.    new_picture.f.linesize[0] =
-        s->m.current_picture.f.linesize[0] = stride;
-        s->m.uvlinesize= s->current_picture.linesize[1];
-        s->m.width = width;
-        s->m.height= height;
-        s->m.mb_width = block_width;
-        s->m.mb_height= block_height;
-        s->m.mb_stride=   s->m.mb_width+1;
-        s->m.b8_stride= 2*s->m.mb_width+1;
-        s->m.f_code=1;
-        s->m.pict_type= pict->pict_type;
-        s->m.me_method= s->avctx->me_method;
-        s->m.me.scene_change_score=0;
-        s->m.flags= s->avctx->flags;
-        s->m.quarter_sample= (s->avctx->flags & CODEC_FLAG_QPEL)!=0;
-        s->m.out_format= FMT_H263;
-        s->m.unrestricted_mv= 1;
-
-        s->m.lambda = s->lambda;
-        s->m.qscale= (s->m.lambda*139 + FF_LAMBDA_SCALE*64) >> (FF_LAMBDA_SHIFT + 7);
-        s->lambda2= s->m.lambda2= (s->m.lambda*s->m.lambda + FF_LAMBDA_SCALE/2) >> FF_LAMBDA_SHIFT;
-
-        s->m.dsp= s->dsp; //move
-        ff_init_me(&s->m);
-        s->dsp= s->m.dsp;
-    }
-
-    if(s->pass1_rc){
-        memcpy(rc_header_bak, s->header_state, sizeof(s->header_state));
-        memcpy(rc_block_bak, s->block_state, sizeof(s->block_state));
-    }
-
-redo_frame:
-
-    if(pict->pict_type == AV_PICTURE_TYPE_I)
-        s->spatial_decomposition_count= 5;
-    else
-        s->spatial_decomposition_count= 5;
-
-    s->m.pict_type = pict->pict_type;
-    s->qbias= pict->pict_type == AV_PICTURE_TYPE_P ? 2 : 0;
-
-    common_init_after_header(avctx);
-
-    if(s->last_spatial_decomposition_count != s->spatial_decomposition_count){
-        for(plane_index=0; plane_index<3; plane_index++){
-            calculate_visual_weight(s, &s->plane[plane_index]);
-        }
-    }
-
-    encode_header(s);
-    s->m.misc_bits = 8*(s->c.bytestream - s->c.bytestream_start);
-    encode_blocks(s, 1);
-    s->m.mv_bits = 8*(s->c.bytestream - s->c.bytestream_start) - s->m.misc_bits;
-
-    for(plane_index=0; plane_index<3; plane_index++){
-        Plane *p= &s->plane[plane_index];
-        int w= p->width;
-        int h= p->height;
-        int x, y;
-//        int bits= put_bits_count(&s->c.pb);
-
-        if (!s->memc_only) {
-            //FIXME optimize
-            if(pict->data[plane_index]) //FIXME gray hack
-                for(y=0; y<h; y++){
-                    for(x=0; x<w; x++){
-                        s->spatial_idwt_buffer[y*w + x]= pict->data[plane_index][y*pict->linesize[plane_index] + x]<<FRAC_BITS;
-                    }
-                }
-            predict_plane(s, s->spatial_idwt_buffer, plane_index, 0);
-
-            if(   plane_index==0
-               && pict->pict_type == AV_PICTURE_TYPE_P
-               && !(avctx->flags&CODEC_FLAG_PASS2)
-               && s->m.me.scene_change_score > s->avctx->scenechange_threshold){
-                ff_init_range_encoder(c, buf, buf_size);
-                ff_build_rac_states(c, 0.05*(1LL<<32), 256-8);
-                pict->pict_type= AV_PICTURE_TYPE_I;
-                s->keyframe=1;
-                s->current_picture.key_frame=1;
-                goto redo_frame;
-            }
-
-            if(s->qlog == LOSSLESS_QLOG){
-                for(y=0; y<h; y++){
-                    for(x=0; x<w; x++){
-                        s->spatial_dwt_buffer[y*w + x]= (s->spatial_idwt_buffer[y*w + x] + (1<<(FRAC_BITS-1))-1)>>FRAC_BITS;
-                    }
-                }
-            }else{
-                for(y=0; y<h; y++){
-                    for(x=0; x<w; x++){
-                        s->spatial_dwt_buffer[y*w + x]=s->spatial_idwt_buffer[y*w + x]<<ENCODER_EXTRA_BITS;
-                    }
-                }
-            }
-
-            /*  if(QUANTIZE2)
-                dwt_quantize(s, p, s->spatial_dwt_buffer, w, h, w, s->spatial_decomposition_type);
-            else*/
-                ff_spatial_dwt(s->spatial_dwt_buffer, w, h, w, s->spatial_decomposition_type, s->spatial_decomposition_count);
-
-            if(s->pass1_rc && plane_index==0){
-                int delta_qlog = ratecontrol_1pass(s, pict);
-                if (delta_qlog <= INT_MIN)
-                    return -1;
-                if(delta_qlog){
-                    //reordering qlog in the bitstream would eliminate this reset
-                    ff_init_range_encoder(c, buf, buf_size);
-                    memcpy(s->header_state, rc_header_bak, sizeof(s->header_state));
-                    memcpy(s->block_state, rc_block_bak, sizeof(s->block_state));
-                    encode_header(s);
-                    encode_blocks(s, 0);
-                }
-            }
-
-            for(level=0; level<s->spatial_decomposition_count; level++){
-                for(orientation=level ? 1 : 0; orientation<4; orientation++){
-                    SubBand *b= &p->band[level][orientation];
-
-                    if(!QUANTIZE2)
-                        quantize(s, b, b->ibuf, b->buf, b->stride, s->qbias);
-                    if(orientation==0)
-                        decorrelate(s, b, b->ibuf, b->stride, pict->pict_type == AV_PICTURE_TYPE_P, 0);
-                    encode_subband(s, b, b->ibuf, b->parent ? b->parent->ibuf : NULL, b->stride, orientation);
-                    assert(b->parent==NULL || b->parent->stride == b->stride*2);
-                    if(orientation==0)
-                        correlate(s, b, b->ibuf, b->stride, 1, 0);
-                }
-            }
-
-            for(level=0; level<s->spatial_decomposition_count; level++){
-                for(orientation=level ? 1 : 0; orientation<4; orientation++){
-                    SubBand *b= &p->band[level][orientation];
-
-                    dequantize(s, b, b->ibuf, b->stride);
-                }
-            }
-
-            ff_spatial_idwt(s->spatial_idwt_buffer, w, h, w, s->spatial_decomposition_type, s->spatial_decomposition_count);
-            if(s->qlog == LOSSLESS_QLOG){
-                for(y=0; y<h; y++){
-                    for(x=0; x<w; x++){
-                        s->spatial_idwt_buffer[y*w + x]<<=FRAC_BITS;
-                    }
-                }
-            }
-            predict_plane(s, s->spatial_idwt_buffer, plane_index, 1);
-        }else{
-            //ME/MC only
-            if(pict->pict_type == AV_PICTURE_TYPE_I){
-                for(y=0; y<h; y++){
-                    for(x=0; x<w; x++){
-                        s->current_picture.data[plane_index][y*s->current_picture.linesize[plane_index] + x]=
-                            pict->data[plane_index][y*pict->linesize[plane_index] + x];
-                    }
-                }
-            }else{
-                memset(s->spatial_idwt_buffer, 0, sizeof(IDWTELEM)*w*h);
-                predict_plane(s, s->spatial_idwt_buffer, plane_index, 1);
-            }
-        }
-        if(s->avctx->flags&CODEC_FLAG_PSNR){
-            int64_t error= 0;
-
-            if(pict->data[plane_index]) //FIXME gray hack
-                for(y=0; y<h; y++){
-                    for(x=0; x<w; x++){
-                        int d= s->current_picture.data[plane_index][y*s->current_picture.linesize[plane_index] + x] - pict->data[plane_index][y*pict->linesize[plane_index] + x];
-                        error += d*d;
-                    }
-                }
-            s->avctx->error[plane_index] += error;
-            s->current_picture.error[plane_index] = error;
-        }
-
-    }
-
-    update_last_header_values(s);
-
-    release_buffer(avctx);
-
-    s->current_picture.coded_picture_number = avctx->frame_number;
-    s->current_picture.pict_type = pict->pict_type;
-    s->current_picture.quality = pict->quality;
-    s->m.frame_bits = 8*(s->c.bytestream - s->c.bytestream_start);
-    s->m.p_tex_bits = s->m.frame_bits - s->m.misc_bits - s->m.mv_bits;
-    s->m.current_picture.f.display_picture_number =
-    s->m.current_picture.f.coded_picture_number   = avctx->frame_number;
-    s->m.current_picture.f.quality                = pict->quality;
-    s->m.total_bits += 8*(s->c.bytestream - s->c.bytestream_start);
-    if(s->pass1_rc)
-        if (ff_rate_estimate_qscale(&s->m, 0) < 0)
-            return -1;
-    if(avctx->flags&CODEC_FLAG_PASS1)
-        ff_write_pass1_stats(&s->m);
-    s->m.last_pict_type = s->m.pict_type;
-    avctx->frame_bits = s->m.frame_bits;
-    avctx->mv_bits = s->m.mv_bits;
-    avctx->misc_bits = s->m.misc_bits;
-    avctx->p_tex_bits = s->m.p_tex_bits;
-
-    emms_c();
-
-    return ff_rac_terminate(c);
-}
-
-static av_cold int encode_end(AVCodecContext *avctx)
-{
-    SnowContext *s = avctx->priv_data;
-
-    common_end(s);
-    if (s->input_picture.data[0])
-        avctx->release_buffer(avctx, &s->input_picture);
-    av_free(avctx->stats_out);
-
-    return 0;
-}
-
-#define OFFSET(x) offsetof(SnowContext, x)
-#define VE AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_ENCODING_PARAM
-static const AVOption options[] = {
-    { "memc_only",      "Only do ME/MC (I frames -> ref, P frame -> ME+MC).",   OFFSET(memc_only), AV_OPT_TYPE_INT, { 0 }, 0, 1, VE },
-    { NULL },
-};
-
-static const AVClass snowenc_class = {
-    .class_name = "snow encoder",
-    .item_name  = av_default_item_name,
-    .option     = options,
-    .version    = LIBAVUTIL_VERSION_INT,
-};
-
-AVCodec ff_snow_encoder = {
-    .name           = "snow",
-    .type           = AVMEDIA_TYPE_VIDEO,
-    .id             = CODEC_ID_SNOW,
-    .priv_data_size = sizeof(SnowContext),
-    .init           = encode_init,
-    .encode         = encode_frame,
-    .close          = encode_end,
-    .long_name = NULL_IF_CONFIG_SMALL("Snow"),
-    .priv_class     = &snowenc_class,
-};
-#endif
diff --git a/libavcodec/snow.h b/libavcodec/snow.h
index db61b87..f43deb1 100644
--- a/libavcodec/snow.h
+++ b/libavcodec/snow.h
@@ -25,6 +25,10 @@
 #include "dsputil.h"
 #include "dwt.h"
 
+#include "rangecoder.h"
+#include "mathops.h"
+#include "mpegvideo.h"
+
 #define MID_STATE 128
 
 #define MAX_PLANES 4
@@ -36,6 +40,138 @@
 
 #define LOG2_OBMC_MAX 8
 #define OBMC_MAX (1<<(LOG2_OBMC_MAX))
+typedef struct BlockNode{
+    int16_t mx;
+    int16_t my;
+    uint8_t ref;
+    uint8_t color[3];
+    uint8_t type;
+//#define TYPE_SPLIT    1
+#define BLOCK_INTRA   1
+#define BLOCK_OPT     2
+//#define TYPE_NOCOLOR  4
+    uint8_t level; //FIXME merge into type?
+}BlockNode;
+
+static const BlockNode null_block= { //FIXME add border maybe
+    .color= {128,128,128},
+    .mx= 0,
+    .my= 0,
+    .ref= 0,
+    .type= 0,
+    .level= 0,
+};
+
+#define LOG2_MB_SIZE 4
+#define MB_SIZE (1<<LOG2_MB_SIZE)
+#define ENCODER_EXTRA_BITS 4
+#define HTAPS_MAX 8
+
+typedef struct x_and_coeff{
+    int16_t x;
+    uint16_t coeff;
+} x_and_coeff;
+
+typedef struct SubBand{
+    int level;
+    int stride;
+    int width;
+    int height;
+    int qlog;        ///< log(qscale)/log[2^(1/6)]
+    DWTELEM *buf;
+    IDWTELEM *ibuf;
+    int buf_x_offset;
+    int buf_y_offset;
+    int stride_line; ///< Stride measured in lines, not pixels.
+    x_and_coeff * x_coeff;
+    struct SubBand *parent;
+    uint8_t state[/*7*2*/ 7 + 512][32];
+}SubBand;
+
+typedef struct Plane{
+    int width;
+    int height;
+    SubBand band[MAX_DECOMPOSITIONS][4];
+
+    int htaps;
+    int8_t hcoeff[HTAPS_MAX/2];
+    int diag_mc;
+    int fast_mc;
+
+    int last_htaps;
+    int8_t last_hcoeff[HTAPS_MAX/2];
+    int last_diag_mc;
+}Plane;
+
+typedef struct SnowContext{
+    AVClass *class;
+    AVCodecContext *avctx;
+    RangeCoder c;
+    DSPContext dsp;
+    DWTContext dwt;
+    AVFrame new_picture;
+    AVFrame input_picture;              ///< new_picture with the internal linesizes
+    AVFrame current_picture;
+    AVFrame last_picture[MAX_REF_FRAMES];
+    uint8_t *halfpel_plane[MAX_REF_FRAMES][4][4];
+    AVFrame mconly_picture;
+//     uint8_t q_context[16];
+    uint8_t header_state[32];
+    uint8_t block_state[128 + 32*128];
+    int keyframe;
+    int always_reset;
+    int version;
+    int spatial_decomposition_type;
+    int last_spatial_decomposition_type;
+    int temporal_decomposition_type;
+    int spatial_decomposition_count;
+    int last_spatial_decomposition_count;
+    int temporal_decomposition_count;
+    int max_ref_frames;
+    int ref_frames;
+    int16_t (*ref_mvs[MAX_REF_FRAMES])[2];
+    uint32_t *ref_scores[MAX_REF_FRAMES];
+    DWTELEM *spatial_dwt_buffer;
+    IDWTELEM *spatial_idwt_buffer;
+    int colorspace_type;
+    int chroma_h_shift;
+    int chroma_v_shift;
+    int spatial_scalability;
+    int qlog;
+    int last_qlog;
+    int lambda;
+    int lambda2;
+    int pass1_rc;
+    int mv_scale;
+    int last_mv_scale;
+    int qbias;
+    int last_qbias;
+#define QBIAS_SHIFT 3
+    int b_width;
+    int b_height;
+    int block_max_depth;
+    int last_block_max_depth;
+    Plane plane[MAX_PLANES];
+    BlockNode *block;
+#define ME_CACHE_SIZE 1024
+    int me_cache[ME_CACHE_SIZE];
+    int me_cache_generation;
+    slice_buffer sb;
+    int memc_only;
+
+    MpegEncContext m; // needed for motion estimation, should not be used for anything else, the idea is to eventually make the motion estimation independent of MpegEncContext, so this will be removed then (FIXME/XXX)
+
+    uint8_t *scratchbuf;
+}SnowContext;
+
+/* Tables */
+extern const uint8_t * const obmc_tab[4];
+#ifdef __sgi
+// Avoid a name clash on SGI IRIX
+#undef qexp
+#endif
+extern uint8_t qexp[QROOT];
+extern int scale_mv_ref[MAX_REF_FRAMES][MAX_REF_FRAMES];
 
 /* C bits used by mmx/sse2/altivec */
 
@@ -75,4 +211,482 @@ static av_always_inline void snow_horizontal_compose_liftS_lead_out(int i, IDWTE
         }
 }
 
+/* common code */
+
+int ff_snow_common_init(AVCodecContext *avctx);
+int ff_snow_common_init_after_header(AVCodecContext *avctx);
+void ff_snow_common_end(SnowContext *s);
+void ff_snow_release_buffer(AVCodecContext *avctx);
+void ff_snow_reset_contexts(SnowContext *s);
+int ff_snow_alloc_blocks(SnowContext *s);
+int ff_snow_frame_start(SnowContext *s);
+void ff_snow_pred_block(SnowContext *s, uint8_t *dst, uint8_t *tmp, int stride,
+                     int sx, int sy, int b_w, int b_h, BlockNode *block,
+                     int plane_index, int w, int h);
+/* common inline functions */
+//XXX doublecheck all of them should stay inlined
+
+static inline void snow_set_blocks(SnowContext *s, int level, int x, int y, int l, int cb, int cr, int mx, int my, int ref, int type){
+    const int w= s->b_width << s->block_max_depth;
+    const int rem_depth= s->block_max_depth - level;
+    const int index= (x + y*w) << rem_depth;
+    const int block_w= 1<<rem_depth;
+    BlockNode block;
+    int i,j;
+
+    block.color[0]= l;
+    block.color[1]= cb;
+    block.color[2]= cr;
+    block.mx= mx;
+    block.my= my;
+    block.ref= ref;
+    block.type= type;
+    block.level= level;
+
+    for(j=0; j<block_w; j++){
+        for(i=0; i<block_w; i++){
+            s->block[index + i + j*w]= block;
+        }
+    }
+}
+
+static inline void pred_mv(SnowContext *s, int *mx, int *my, int ref,
+                           const BlockNode *left, const BlockNode *top, const BlockNode *tr){
+    if(s->ref_frames == 1){
+        *mx = mid_pred(left->mx, top->mx, tr->mx);
+        *my = mid_pred(left->my, top->my, tr->my);
+    }else{
+        const int *scale = scale_mv_ref[ref];
+        *mx = mid_pred((left->mx * scale[left->ref] + 128) >>8,
+                       (top ->mx * scale[top ->ref] + 128) >>8,
+                       (tr  ->mx * scale[tr  ->ref] + 128) >>8);
+        *my = mid_pred((left->my * scale[left->ref] + 128) >>8,
+                       (top ->my * scale[top ->ref] + 128) >>8,
+                       (tr  ->my * scale[tr  ->ref] + 128) >>8);
+    }
+}
+
+static av_always_inline int same_block(BlockNode *a, BlockNode *b){
+    if((a->type&BLOCK_INTRA) && (b->type&BLOCK_INTRA)){
+        return !((a->color[0] - b->color[0]) | (a->color[1] - b->color[1]) | (a->color[2] - b->color[2]));
+    }else{
+        return !((a->mx - b->mx) | (a->my - b->my) | (a->ref - b->ref) | ((a->type ^ b->type)&BLOCK_INTRA));
+    }
+}
+
+//FIXME name cleanup (b_w, block_w, b_width stuff)
+//XXX should we really inline it?
+static av_always_inline void add_yblock(SnowContext *s, int sliced, slice_buffer *sb, IDWTELEM *dst, uint8_t *dst8, const uint8_t *obmc, int src_x, int src_y, int b_w, int b_h, int w, int h, int dst_stride, int src_stride, int obmc_stride, int b_x, int b_y, int add, int offset_dst, int plane_index){
+    const int b_width = s->b_width  << s->block_max_depth;
+    const int b_height= s->b_height << s->block_max_depth;
+    const int b_stride= b_width;
+    BlockNode *lt= &s->block[b_x + b_y*b_stride];
+    BlockNode *rt= lt+1;
+    BlockNode *lb= lt+b_stride;
+    BlockNode *rb= lb+1;
+    uint8_t *block[4];
+    int tmp_step= src_stride >= 7*MB_SIZE ? MB_SIZE : MB_SIZE*src_stride;
+    uint8_t *tmp = s->scratchbuf;
+    uint8_t *ptmp;
+    int x,y;
+
+    if(b_x<0){
+        lt= rt;
+        lb= rb;
+    }else if(b_x + 1 >= b_width){
+        rt= lt;
+        rb= lb;
+    }
+    if(b_y<0){
+        lt= lb;
+        rt= rb;
+    }else if(b_y + 1 >= b_height){
+        lb= lt;
+        rb= rt;
+    }
+
+    if(src_x<0){ //FIXME merge with prev & always round internal width up to *16
+        obmc -= src_x;
+        b_w += src_x;
+        if(!sliced && !offset_dst)
+            dst -= src_x;
+        src_x=0;
+    }else if(src_x + b_w > w){
+        b_w = w - src_x;
+    }
+    if(src_y<0){
+        obmc -= src_y*obmc_stride;
+        b_h += src_y;
+        if(!sliced && !offset_dst)
+            dst -= src_y*dst_stride;
+        src_y=0;
+    }else if(src_y + b_h> h){
+        b_h = h - src_y;
+    }
+
+    if(b_w<=0 || b_h<=0) return;
+
+    assert(src_stride > 2*MB_SIZE + 5);
+
+    if(!sliced && offset_dst)
+        dst += src_x + src_y*dst_stride;
+    dst8+= src_x + src_y*src_stride;
+//    src += src_x + src_y*src_stride;
+
+    ptmp= tmp + 3*tmp_step;
+    block[0]= ptmp;
+    ptmp+=tmp_step;
+    ff_snow_pred_block(s, block[0], tmp, src_stride, src_x, src_y, b_w, b_h, lt, plane_index, w, h);
+
+    if(same_block(lt, rt)){
+        block[1]= block[0];
+    }else{
+        block[1]= ptmp;
+        ptmp+=tmp_step;
+        ff_snow_pred_block(s, block[1], tmp, src_stride, src_x, src_y, b_w, b_h, rt, plane_index, w, h);
+    }
+
+    if(same_block(lt, lb)){
+        block[2]= block[0];
+    }else if(same_block(rt, lb)){
+        block[2]= block[1];
+    }else{
+        block[2]= ptmp;
+        ptmp+=tmp_step;
+        ff_snow_pred_block(s, block[2], tmp, src_stride, src_x, src_y, b_w, b_h, lb, plane_index, w, h);
+    }
+
+    if(same_block(lt, rb) ){
+        block[3]= block[0];
+    }else if(same_block(rt, rb)){
+        block[3]= block[1];
+    }else if(same_block(lb, rb)){
+        block[3]= block[2];
+    }else{
+        block[3]= ptmp;
+        ff_snow_pred_block(s, block[3], tmp, src_stride, src_x, src_y, b_w, b_h, rb, plane_index, w, h);
+    }
+    if(sliced){
+        s->dwt.inner_add_yblock(obmc, obmc_stride, block, b_w, b_h, src_x,src_y, src_stride, sb, add, dst8);
+    }else{
+        for(y=0; y<b_h; y++){
+            //FIXME ugly misuse of obmc_stride
+            const uint8_t *obmc1= obmc + y*obmc_stride;
+            const uint8_t *obmc2= obmc1+ (obmc_stride>>1);
+            const uint8_t *obmc3= obmc1+ obmc_stride*(obmc_stride>>1);
+            const uint8_t *obmc4= obmc3+ (obmc_stride>>1);
+            for(x=0; x<b_w; x++){
+                int v=   obmc1[x] * block[3][x + y*src_stride]
+                        +obmc2[x] * block[2][x + y*src_stride]
+                        +obmc3[x] * block[1][x + y*src_stride]
+                        +obmc4[x] * block[0][x + y*src_stride];
+
+                v <<= 8 - LOG2_OBMC_MAX;
+                if(FRAC_BITS != 8){
+                    v >>= 8 - FRAC_BITS;
+                }
+                if(add){
+                    v += dst[x + y*dst_stride];
+                    v = (v + (1<<(FRAC_BITS-1))) >> FRAC_BITS;
+                    if(v&(~255)) v= ~(v>>31);
+                    dst8[x + y*src_stride] = v;
+                }else{
+                    dst[x + y*dst_stride] -= v;
+                }
+            }
+        }
+    }
+}
+
+static av_always_inline void predict_slice(SnowContext *s, IDWTELEM *buf, int plane_index, int add, int mb_y){
+    Plane *p= &s->plane[plane_index];
+    const int mb_w= s->b_width  << s->block_max_depth;
+    const int mb_h= s->b_height << s->block_max_depth;
+    int x, y, mb_x;
+    int block_size = MB_SIZE >> s->block_max_depth;
+    int block_w    = plane_index ? block_size/2 : block_size;
+    const uint8_t *obmc  = plane_index ? obmc_tab[s->block_max_depth+1] : obmc_tab[s->block_max_depth];
+    const int obmc_stride= plane_index ? block_size : 2*block_size;
+    int ref_stride= s->current_picture.linesize[plane_index];
+    uint8_t *dst8= s->current_picture.data[plane_index];
+    int w= p->width;
+    int h= p->height;
+
+    if(s->keyframe || (s->avctx->debug&512)){
+        if(mb_y==mb_h)
+            return;
+
+        if(add){
+            for(y=block_w*mb_y; y<FFMIN(h,block_w*(mb_y+1)); y++){
+                for(x=0; x<w; x++){
+                    int v= buf[x + y*w] + (128<<FRAC_BITS) + (1<<(FRAC_BITS-1));
+                    v >>= FRAC_BITS;
+                    if(v&(~255)) v= ~(v>>31);
+                    dst8[x + y*ref_stride]= v;
+                }
+            }
+        }else{
+            for(y=block_w*mb_y; y<FFMIN(h,block_w*(mb_y+1)); y++){
+                for(x=0; x<w; x++){
+                    buf[x + y*w]-= 128<<FRAC_BITS;
+                }
+            }
+        }
+
+        return;
+    }
+
+    for(mb_x=0; mb_x<=mb_w; mb_x++){
+        add_yblock(s, 0, NULL, buf, dst8, obmc,
+                   block_w*mb_x - block_w/2,
+                   block_w*mb_y - block_w/2,
+                   block_w, block_w,
+                   w, h,
+                   w, ref_stride, obmc_stride,
+                   mb_x - 1, mb_y - 1,
+                   add, 1, plane_index);
+    }
+}
+
+static av_always_inline void predict_plane(SnowContext *s, IDWTELEM *buf, int plane_index, int add){
+    const int mb_h= s->b_height << s->block_max_depth;
+    int mb_y;
+    for(mb_y=0; mb_y<=mb_h; mb_y++)
+        predict_slice(s, buf, plane_index, add, mb_y);
+}
+
+static inline void set_blocks(SnowContext *s, int level, int x, int y, int l, int cb, int cr, int mx, int my, int ref, int type){
+    const int w= s->b_width << s->block_max_depth;
+    const int rem_depth= s->block_max_depth - level;
+    const int index= (x + y*w) << rem_depth;
+    const int block_w= 1<<rem_depth;
+    BlockNode block;
+    int i,j;
+
+    block.color[0]= l;
+    block.color[1]= cb;
+    block.color[2]= cr;
+    block.mx= mx;
+    block.my= my;
+    block.ref= ref;
+    block.type= type;
+    block.level= level;
+
+    for(j=0; j<block_w; j++){
+        for(i=0; i<block_w; i++){
+            s->block[index + i + j*w]= block;
+        }
+    }
+}
+
+static inline void init_ref(MotionEstContext *c, uint8_t *src[3], uint8_t *ref[3], uint8_t *ref2[3], int x, int y, int ref_index){
+    const int offset[3]= {
+          y*c->  stride + x,
+        ((y*c->uvstride + x)>>1),
+        ((y*c->uvstride + x)>>1),
+    };
+    int i;
+    for(i=0; i<3; i++){
+        c->src[0][i]= src [i];
+        c->ref[0][i]= ref [i] + offset[i];
+    }
+    assert(!ref_index);
+}
+
+
+/* bitstream functions */
+
+extern const int8_t quant3bA[256];
+
+#define QEXPSHIFT (7-FRAC_BITS+8) //FIXME try to change this to 0
+
+static inline void put_symbol(RangeCoder *c, uint8_t *state, int v, int is_signed){
+    int i;
+
+    if(v){
+        const int a= FFABS(v);
+        const int e= av_log2(a);
+        const int el= FFMIN(e, 10);
+        put_rac(c, state+0, 0);
+
+        for(i=0; i<el; i++){
+            put_rac(c, state+1+i, 1);  //1..10
+        }
+        for(; i<e; i++){
+            put_rac(c, state+1+9, 1);  //1..10
+        }
+        put_rac(c, state+1+FFMIN(i,9), 0);
+
+        for(i=e-1; i>=el; i--){
+            put_rac(c, state+22+9, (a>>i)&1); //22..31
+        }
+        for(; i>=0; i--){
+            put_rac(c, state+22+i, (a>>i)&1); //22..31
+        }
+
+        if(is_signed)
+            put_rac(c, state+11 + el, v < 0); //11..21
+    }else{
+        put_rac(c, state+0, 1);
+    }
+}
+
+static inline int get_symbol(RangeCoder *c, uint8_t *state, int is_signed){
+    if(get_rac(c, state+0))
+        return 0;
+    else{
+        int i, e, a;
+        e= 0;
+        while(get_rac(c, state+1 + FFMIN(e,9))){ //1..10
+            e++;
+        }
+
+        a= 1;
+        for(i=e-1; i>=0; i--){
+            a += a + get_rac(c, state+22 + FFMIN(i,9)); //22..31
+        }
+
+        e= -(is_signed && get_rac(c, state+11 + FFMIN(e,10))); //11..21
+        return (a^e)-e;
+    }
+}
+
+static inline void put_symbol2(RangeCoder *c, uint8_t *state, int v, int log2){
+    int i;
+    int r= log2>=0 ? 1<<log2 : 1;
+
+    assert(v>=0);
+    assert(log2>=-4);
+
+    while(v >= r){
+        put_rac(c, state+4+log2, 1);
+        v -= r;
+        log2++;
+        if(log2>0) r+=r;
+    }
+    put_rac(c, state+4+log2, 0);
+
+    for(i=log2-1; i>=0; i--){
+        put_rac(c, state+31-i, (v>>i)&1);
+    }
+}
+
+static inline int get_symbol2(RangeCoder *c, uint8_t *state, int log2){
+    int i;
+    int r= log2>=0 ? 1<<log2 : 1;
+    int v=0;
+
+    assert(log2>=-4);
+
+    while(get_rac(c, state+4+log2)){
+        v+= r;
+        log2++;
+        if(log2>0) r+=r;
+    }
+
+    for(i=log2-1; i>=0; i--){
+        v+= get_rac(c, state+31-i)<<i;
+    }
+
+    return v;
+}
+
+static inline void unpack_coeffs(SnowContext *s, SubBand *b, SubBand * parent, int orientation){
+    const int w= b->width;
+    const int h= b->height;
+    int x,y;
+
+    int run, runs;
+    x_and_coeff *xc= b->x_coeff;
+    x_and_coeff *prev_xc= NULL;
+    x_and_coeff *prev2_xc= xc;
+    x_and_coeff *parent_xc= parent ? parent->x_coeff : NULL;
+    x_and_coeff *prev_parent_xc= parent_xc;
+
+    runs= get_symbol2(&s->c, b->state[30], 0);
+    if(runs-- > 0) run= get_symbol2(&s->c, b->state[1], 3);
+    else           run= INT_MAX;
+
+    for(y=0; y<h; y++){
+        int v=0;
+        int lt=0, t=0, rt=0;
+
+        if(y && prev_xc->x == 0){
+            rt= prev_xc->coeff;
+        }
+        for(x=0; x<w; x++){
+            int p=0;
+            const int l= v;
+
+            lt= t; t= rt;
+
+            if(y){
+                if(prev_xc->x <= x)
+                    prev_xc++;
+                if(prev_xc->x == x + 1)
+                    rt= prev_xc->coeff;
+                else
+                    rt=0;
+            }
+            if(parent_xc){
+                if(x>>1 > parent_xc->x){
+                    parent_xc++;
+                }
+                if(x>>1 == parent_xc->x){
+                    p= parent_xc->coeff;
+                }
+            }
+            if(/*ll|*/l|lt|t|rt|p){
+                int context= av_log2(/*FFABS(ll) + */3*(l>>1) + (lt>>1) + (t&~1) + (rt>>1) + (p>>1));
+
+                v=get_rac(&s->c, &b->state[0][context]);
+                if(v){
+                    v= 2*(get_symbol2(&s->c, b->state[context + 2], context-4) + 1);
+                    v+=get_rac(&s->c, &b->state[0][16 + 1 + 3 + quant3bA[l&0xFF] + 3*quant3bA[t&0xFF]]);
+
+                    xc->x=x;
+                    (xc++)->coeff= v;
+                }
+            }else{
+                if(!run){
+                    if(runs-- > 0) run= get_symbol2(&s->c, b->state[1], 3);
+                    else           run= INT_MAX;
+                    v= 2*(get_symbol2(&s->c, b->state[0 + 2], 0-4) + 1);
+                    v+=get_rac(&s->c, &b->state[0][16 + 1 + 3]);
+
+                    xc->x=x;
+                    (xc++)->coeff= v;
+                }else{
+                    int max_run;
+                    run--;
+                    v=0;
+
+                    if(y) max_run= FFMIN(run, prev_xc->x - x - 2);
+                    else  max_run= FFMIN(run, w-x-1);
+                    if(parent_xc)
+                        max_run= FFMIN(max_run, 2*parent_xc->x - x - 1);
+                    x+= max_run;
+                    run-= max_run;
+                }
+            }
+        }
+        (xc++)->x= w+1; //end marker
+        prev_xc= prev2_xc;
+        prev2_xc= xc;
+
+        if(parent_xc){
+            if(y&1){
+                while(parent_xc->x != parent->width+1)
+                    parent_xc++;
+                parent_xc++;
+                prev_parent_xc= parent_xc;
+            }else{
+                parent_xc= prev_parent_xc;
+            }
+        }
+    }
+
+    (xc++)->x= w+1; //end marker
+}
+
 #endif /* AVCODEC_SNOW_H */
diff --git a/libavcodec/snowdata.h b/libavcodec/snowdata.h
new file mode 100644
index 0000000..ca2468c
--- /dev/null
+++ b/libavcodec/snowdata.h
@@ -0,0 +1,132 @@
+/*
+ * Copyright (C) 2004 Michael Niedermayer <michaelni at gmx.at>
+ * Copyright (C) 2006 Robert Edele <yartrebo at earthlink.net>
+ *
+ * This file is part of Libav.
+ *
+ * Libav is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * Libav is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with Libav; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef AVCODEC_SNOWDATA_H
+#define AVCODEC_SNOWDATA_H
+
+#include "snow.h"
+
+static const uint8_t obmc32[1024]={
+  0,  0,  0,  0,  4,  4,  4,  4,  4,  4,  4,  4,  8,  8,  8,  8,  8,  8,  8,  8,  4,  4,  4,  4,  4,  4,  4,  4,  0,  0,  0,  0,
+  0,  4,  4,  4,  8,  8,  8, 12, 12, 16, 16, 16, 20, 20, 20, 24, 24, 20, 20, 20, 16, 16, 16, 12, 12,  8,  8,  8,  4,  4,  4,  0,
+  0,  4,  8,  8, 12, 12, 16, 20, 20, 24, 28, 28, 32, 32, 36, 40, 40, 36, 32, 32, 28, 28, 24, 20, 20, 16, 12, 12,  8,  8,  4,  0,
+  0,  4,  8, 12, 16, 20, 24, 28, 28, 32, 36, 40, 44, 48, 52, 56, 56, 52, 48, 44, 40, 36, 32, 28, 28, 24, 20, 16, 12,  8,  4,  0,
+  4,  8, 12, 16, 20, 24, 28, 32, 40, 44, 48, 52, 56, 60, 64, 68, 68, 64, 60, 56, 52, 48, 44, 40, 32, 28, 24, 20, 16, 12,  8,  4,
+  4,  8, 12, 20, 24, 32, 36, 40, 48, 52, 56, 64, 68, 76, 80, 84, 84, 80, 76, 68, 64, 56, 52, 48, 40, 36, 32, 24, 20, 12,  8,  4,
+  4,  8, 16, 24, 28, 36, 44, 48, 56, 60, 68, 76, 80, 88, 96,100,100, 96, 88, 80, 76, 68, 60, 56, 48, 44, 36, 28, 24, 16,  8,  4,
+  4, 12, 20, 28, 32, 40, 48, 56, 64, 72, 80, 88, 92,100,108,116,116,108,100, 92, 88, 80, 72, 64, 56, 48, 40, 32, 28, 20, 12,  4,
+  4, 12, 20, 28, 40, 48, 56, 64, 72, 80, 88, 96,108,116,124,132,132,124,116,108, 96, 88, 80, 72, 64, 56, 48, 40, 28, 20, 12,  4,
+  4, 16, 24, 32, 44, 52, 60, 72, 80, 92,100,108,120,128,136,148,148,136,128,120,108,100, 92, 80, 72, 60, 52, 44, 32, 24, 16,  4,
+  4, 16, 28, 36, 48, 56, 68, 80, 88,100,112,120,132,140,152,164,164,152,140,132,120,112,100, 88, 80, 68, 56, 48, 36, 28, 16,  4,
+  4, 16, 28, 40, 52, 64, 76, 88, 96,108,120,132,144,156,168,180,180,168,156,144,132,120,108, 96, 88, 76, 64, 52, 40, 28, 16,  4,
+  8, 20, 32, 44, 56, 68, 80, 92,108,120,132,144,156,168,180,192,192,180,168,156,144,132,120,108, 92, 80, 68, 56, 44, 32, 20,  8,
+  8, 20, 32, 48, 60, 76, 88,100,116,128,140,156,168,184,196,208,208,196,184,168,156,140,128,116,100, 88, 76, 60, 48, 32, 20,  8,
+  8, 20, 36, 52, 64, 80, 96,108,124,136,152,168,180,196,212,224,224,212,196,180,168,152,136,124,108, 96, 80, 64, 52, 36, 20,  8,
+  8, 24, 40, 56, 68, 84,100,116,132,148,164,180,192,208,224,240,240,224,208,192,180,164,148,132,116,100, 84, 68, 56, 40, 24,  8,
+  8, 24, 40, 56, 68, 84,100,116,132,148,164,180,192,208,224,240,240,224,208,192,180,164,148,132,116,100, 84, 68, 56, 40, 24,  8,
+  8, 20, 36, 52, 64, 80, 96,108,124,136,152,168,180,196,212,224,224,212,196,180,168,152,136,124,108, 96, 80, 64, 52, 36, 20,  8,
+  8, 20, 32, 48, 60, 76, 88,100,116,128,140,156,168,184,196,208,208,196,184,168,156,140,128,116,100, 88, 76, 60, 48, 32, 20,  8,
+  8, 20, 32, 44, 56, 68, 80, 92,108,120,132,144,156,168,180,192,192,180,168,156,144,132,120,108, 92, 80, 68, 56, 44, 32, 20,  8,
+  4, 16, 28, 40, 52, 64, 76, 88, 96,108,120,132,144,156,168,180,180,168,156,144,132,120,108, 96, 88, 76, 64, 52, 40, 28, 16,  4,
+  4, 16, 28, 36, 48, 56, 68, 80, 88,100,112,120,132,140,152,164,164,152,140,132,120,112,100, 88, 80, 68, 56, 48, 36, 28, 16,  4,
+  4, 16, 24, 32, 44, 52, 60, 72, 80, 92,100,108,120,128,136,148,148,136,128,120,108,100, 92, 80, 72, 60, 52, 44, 32, 24, 16,  4,
+  4, 12, 20, 28, 40, 48, 56, 64, 72, 80, 88, 96,108,116,124,132,132,124,116,108, 96, 88, 80, 72, 64, 56, 48, 40, 28, 20, 12,  4,
+  4, 12, 20, 28, 32, 40, 48, 56, 64, 72, 80, 88, 92,100,108,116,116,108,100, 92, 88, 80, 72, 64, 56, 48, 40, 32, 28, 20, 12,  4,
+  4,  8, 16, 24, 28, 36, 44, 48, 56, 60, 68, 76, 80, 88, 96,100,100, 96, 88, 80, 76, 68, 60, 56, 48, 44, 36, 28, 24, 16,  8,  4,
+  4,  8, 12, 20, 24, 32, 36, 40, 48, 52, 56, 64, 68, 76, 80, 84, 84, 80, 76, 68, 64, 56, 52, 48, 40, 36, 32, 24, 20, 12,  8,  4,
+  4,  8, 12, 16, 20, 24, 28, 32, 40, 44, 48, 52, 56, 60, 64, 68, 68, 64, 60, 56, 52, 48, 44, 40, 32, 28, 24, 20, 16, 12,  8,  4,
+  0,  4,  8, 12, 16, 20, 24, 28, 28, 32, 36, 40, 44, 48, 52, 56, 56, 52, 48, 44, 40, 36, 32, 28, 28, 24, 20, 16, 12,  8,  4,  0,
+  0,  4,  8,  8, 12, 12, 16, 20, 20, 24, 28, 28, 32, 32, 36, 40, 40, 36, 32, 32, 28, 28, 24, 20, 20, 16, 12, 12,  8,  8,  4,  0,
+  0,  4,  4,  4,  8,  8,  8, 12, 12, 16, 16, 16, 20, 20, 20, 24, 24, 20, 20, 20, 16, 16, 16, 12, 12,  8,  8,  8,  4,  4,  4,  0,
+  0,  0,  0,  0,  4,  4,  4,  4,  4,  4,  4,  4,  8,  8,  8,  8,  8,  8,  8,  8,  4,  4,  4,  4,  4,  4,  4,  4,  0,  0,  0,  0,
+ //error:0.000020
+};
+static const uint8_t obmc16[256]={
+  0,  4,  4,  8,  8, 12, 12, 16, 16, 12, 12,  8,  8,  4,  4,  0,
+  4,  8, 16, 20, 28, 32, 40, 44, 44, 40, 32, 28, 20, 16,  8,  4,
+  4, 16, 24, 36, 44, 56, 64, 76, 76, 64, 56, 44, 36, 24, 16,  4,
+  8, 20, 36, 48, 64, 76, 92,104,104, 92, 76, 64, 48, 36, 20,  8,
+  8, 28, 44, 64, 80,100,116,136,136,116,100, 80, 64, 44, 28,  8,
+ 12, 32, 56, 76,100,120,144,164,164,144,120,100, 76, 56, 32, 12,
+ 12, 40, 64, 92,116,144,168,196,196,168,144,116, 92, 64, 40, 12,
+ 16, 44, 76,104,136,164,196,224,224,196,164,136,104, 76, 44, 16,
+ 16, 44, 76,104,136,164,196,224,224,196,164,136,104, 76, 44, 16,
+ 12, 40, 64, 92,116,144,168,196,196,168,144,116, 92, 64, 40, 12,
+ 12, 32, 56, 76,100,120,144,164,164,144,120,100, 76, 56, 32, 12,
+  8, 28, 44, 64, 80,100,116,136,136,116,100, 80, 64, 44, 28,  8,
+  8, 20, 36, 48, 64, 76, 92,104,104, 92, 76, 64, 48, 36, 20,  8,
+  4, 16, 24, 36, 44, 56, 64, 76, 76, 64, 56, 44, 36, 24, 16,  4,
+  4,  8, 16, 20, 28, 32, 40, 44, 44, 40, 32, 28, 20, 16,  8,  4,
+  0,  4,  4,  8,  8, 12, 12, 16, 16, 12, 12,  8,  8,  4,  4,  0,
+//error:0.000015
+};
+
+//linear *64
+static const uint8_t obmc8[64]={
+  4, 12, 20, 28, 28, 20, 12,  4,
+ 12, 36, 60, 84, 84, 60, 36, 12,
+ 20, 60,100,140,140,100, 60, 20,
+ 28, 84,140,196,196,140, 84, 28,
+ 28, 84,140,196,196,140, 84, 28,
+ 20, 60,100,140,140,100, 60, 20,
+ 12, 36, 60, 84, 84, 60, 36, 12,
+  4, 12, 20, 28, 28, 20, 12,  4,
+//error:0.000000
+};
+
+//linear *64
+static const uint8_t obmc4[16]={
+ 16, 48, 48, 16,
+ 48,144,144, 48,
+ 48,144,144, 48,
+ 16, 48, 48, 16,
+//error:0.000000
+};
+
+const int8_t quant3bA[256]={
+ 0, 0, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1,
+ 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1,
+ 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1,
+ 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1,
+ 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1,
+ 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1,
+ 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1,
+ 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1,
+ 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1,
+ 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1,
+ 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1,
+ 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1,
+ 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1,
+ 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1,
+ 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1,
+ 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1, 1,-1,
+};
+
+const uint8_t * const obmc_tab[4]= {
+    obmc32, obmc16, obmc8, obmc4
+};
+
+/* runtime generated tables */
+uint8_t qexp[QROOT];
+int scale_mv_ref[MAX_REF_FRAMES][MAX_REF_FRAMES];
+
+
+#endif /* AVCODEC_SNOW_H */
diff --git a/libavcodec/snowdec.c b/libavcodec/snowdec.c
new file mode 100644
index 0000000..2b6f6e1
--- /dev/null
+++ b/libavcodec/snowdec.c
@@ -0,0 +1,546 @@
+/*
+ * Copyright (C) 2004 Michael Niedermayer <michaelni at gmx.at>
+ *
+ * This file is part of Libav.
+ *
+ * Libav is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * Libav is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with Libav; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "libavutil/intmath.h"
+#include "libavutil/log.h"
+#include "libavutil/opt.h"
+#include "avcodec.h"
+#include "dsputil.h"
+#include "dwt.h"
+#include "snow.h"
+
+#include "rangecoder.h"
+#include "mathops.h"
+
+#include "mpegvideo.h"
+#include "h263.h"
+
+#undef NDEBUG
+#include <assert.h>
+
+static av_always_inline void predict_slice_buffered(SnowContext *s, slice_buffer * sb, IDWTELEM * old_buffer, int plane_index, int add, int mb_y){
+    Plane *p= &s->plane[plane_index];
+    const int mb_w= s->b_width  << s->block_max_depth;
+    const int mb_h= s->b_height << s->block_max_depth;
+    int x, y, mb_x;
+    int block_size = MB_SIZE >> s->block_max_depth;
+    int block_w    = plane_index ? block_size/2 : block_size;
+    const uint8_t *obmc  = plane_index ? obmc_tab[s->block_max_depth+1] : obmc_tab[s->block_max_depth];
+    int obmc_stride= plane_index ? block_size : 2*block_size;
+    int ref_stride= s->current_picture.linesize[plane_index];
+    uint8_t *dst8= s->current_picture.data[plane_index];
+    int w= p->width;
+    int h= p->height;
+
+    if(s->keyframe || (s->avctx->debug&512)){
+        if(mb_y==mb_h)
+            return;
+
+        if(add){
+            for(y=block_w*mb_y; y<FFMIN(h,block_w*(mb_y+1)); y++){
+//                DWTELEM * line = slice_buffer_get_line(sb, y);
+                IDWTELEM * line = sb->line[y];
+                for(x=0; x<w; x++){
+//                    int v= buf[x + y*w] + (128<<FRAC_BITS) + (1<<(FRAC_BITS-1));
+                    int v= line[x] + (128<<FRAC_BITS) + (1<<(FRAC_BITS-1));
+                    v >>= FRAC_BITS;
+                    if(v&(~255)) v= ~(v>>31);
+                    dst8[x + y*ref_stride]= v;
+                }
+            }
+        }else{
+            for(y=block_w*mb_y; y<FFMIN(h,block_w*(mb_y+1)); y++){
+//                DWTELEM * line = slice_buffer_get_line(sb, y);
+                IDWTELEM * line = sb->line[y];
+                for(x=0; x<w; x++){
+                    line[x] -= 128 << FRAC_BITS;
+//                    buf[x + y*w]-= 128<<FRAC_BITS;
+                }
+            }
+        }
+
+        return;
+    }
+
+    for(mb_x=0; mb_x<=mb_w; mb_x++){
+        add_yblock(s, 1, sb, old_buffer, dst8, obmc,
+                   block_w*mb_x - block_w/2,
+                   block_w*mb_y - block_w/2,
+                   block_w, block_w,
+                   w, h,
+                   w, ref_stride, obmc_stride,
+                   mb_x - 1, mb_y - 1,
+                   add, 0, plane_index);
+    }
+}
+
+static inline void decode_subband_slice_buffered(SnowContext *s, SubBand *b, slice_buffer * sb, int start_y, int h, int save_state[1]){
+    const int w= b->width;
+    int y;
+    const int qlog= av_clip(s->qlog + b->qlog, 0, QROOT*16);
+    int qmul= qexp[qlog&(QROOT-1)]<<(qlog>>QSHIFT);
+    int qadd= (s->qbias*qmul)>>QBIAS_SHIFT;
+    int new_index = 0;
+
+    if(b->ibuf == s->spatial_idwt_buffer || s->qlog == LOSSLESS_QLOG){
+        qadd= 0;
+        qmul= 1<<QEXPSHIFT;
+    }
+
+    /* If we are on the second or later slice, restore our index. */
+    if (start_y != 0)
+        new_index = save_state[0];
+
+
+    for(y=start_y; y<h; y++){
+        int x = 0;
+        int v;
+        IDWTELEM * line = slice_buffer_get_line(sb, y * b->stride_line + b->buf_y_offset) + b->buf_x_offset;
+        memset(line, 0, b->width*sizeof(IDWTELEM));
+        v = b->x_coeff[new_index].coeff;
+        x = b->x_coeff[new_index++].x;
+        while(x < w){
+            register int t= ( (v>>1)*qmul + qadd)>>QEXPSHIFT;
+            register int u= -(v&1);
+            line[x] = (t^u) - u;
+
+            v = b->x_coeff[new_index].coeff;
+            x = b->x_coeff[new_index++].x;
+        }
+    }
+
+    /* Save our variables for the next slice. */
+    save_state[0] = new_index;
+
+    return;
+}
+
+static void decode_q_branch(SnowContext *s, int level, int x, int y){
+    const int w= s->b_width << s->block_max_depth;
+    const int rem_depth= s->block_max_depth - level;
+    const int index= (x + y*w) << rem_depth;
+    int trx= (x+1)<<rem_depth;
+    const BlockNode *left  = x ? &s->block[index-1] : &null_block;
+    const BlockNode *top   = y ? &s->block[index-w] : &null_block;
+    const BlockNode *tl    = y && x ? &s->block[index-w-1] : left;
+    const BlockNode *tr    = y && trx<w && ((x&1)==0 || level==0) ? &s->block[index-w+(1<<rem_depth)] : tl; //FIXME use lt
+    int s_context= 2*left->level + 2*top->level + tl->level + tr->level;
+
+    if(s->keyframe){
+        set_blocks(s, level, x, y, null_block.color[0], null_block.color[1], null_block.color[2], null_block.mx, null_block.my, null_block.ref, BLOCK_INTRA);
+        return;
+    }
+
+    if(level==s->block_max_depth || get_rac(&s->c, &s->block_state[4 + s_context])){
+        int type, mx, my;
+        int l = left->color[0];
+        int cb= left->color[1];
+        int cr= left->color[2];
+        int ref = 0;
+        int ref_context= av_log2(2*left->ref) + av_log2(2*top->ref);
+        int mx_context= av_log2(2*FFABS(left->mx - top->mx)) + 0*av_log2(2*FFABS(tr->mx - top->mx));
+        int my_context= av_log2(2*FFABS(left->my - top->my)) + 0*av_log2(2*FFABS(tr->my - top->my));
+
+        type= get_rac(&s->c, &s->block_state[1 + left->type + top->type]) ? BLOCK_INTRA : 0;
+
+        if(type){
+            pred_mv(s, &mx, &my, 0, left, top, tr);
+            l += get_symbol(&s->c, &s->block_state[32], 1);
+            cb+= get_symbol(&s->c, &s->block_state[64], 1);
+            cr+= get_symbol(&s->c, &s->block_state[96], 1);
+        }else{
+            if(s->ref_frames > 1)
+                ref= get_symbol(&s->c, &s->block_state[128 + 1024 + 32*ref_context], 0);
+            pred_mv(s, &mx, &my, ref, left, top, tr);
+            mx+= get_symbol(&s->c, &s->block_state[128 + 32*(mx_context + 16*!!ref)], 1);
+            my+= get_symbol(&s->c, &s->block_state[128 + 32*(my_context + 16*!!ref)], 1);
+        }
+        set_blocks(s, level, x, y, l, cb, cr, mx, my, ref, type);
+    }else{
+        decode_q_branch(s, level+1, 2*x+0, 2*y+0);
+        decode_q_branch(s, level+1, 2*x+1, 2*y+0);
+        decode_q_branch(s, level+1, 2*x+0, 2*y+1);
+        decode_q_branch(s, level+1, 2*x+1, 2*y+1);
+    }
+}
+
+static void dequantize_slice_buffered(SnowContext *s, slice_buffer * sb, SubBand *b, IDWTELEM *src, int stride, int start_y, int end_y){
+    const int w= b->width;
+    const int qlog= av_clip(s->qlog + b->qlog, 0, QROOT*16);
+    const int qmul= qexp[qlog&(QROOT-1)]<<(qlog>>QSHIFT);
+    const int qadd= (s->qbias*qmul)>>QBIAS_SHIFT;
+    int x,y;
+
+    if(s->qlog == LOSSLESS_QLOG) return;
+
+    for(y=start_y; y<end_y; y++){
+//        DWTELEM * line = slice_buffer_get_line_from_address(sb, src + (y * stride));
+        IDWTELEM * line = slice_buffer_get_line(sb, (y * b->stride_line) + b->buf_y_offset) + b->buf_x_offset;
+        for(x=0; x<w; x++){
+            int i= line[x];
+            if(i<0){
+                line[x]= -((-i*qmul + qadd)>>(QEXPSHIFT)); //FIXME try different bias
+            }else if(i>0){
+                line[x]=  (( i*qmul + qadd)>>(QEXPSHIFT));
+            }
+        }
+    }
+}
+
+static void correlate_slice_buffered(SnowContext *s, slice_buffer * sb, SubBand *b, IDWTELEM *src, int stride, int inverse, int use_median, int start_y, int end_y){
+    const int w= b->width;
+    int x,y;
+
+    IDWTELEM * line=0; // silence silly "could be used without having been initialized" warning
+    IDWTELEM * prev;
+
+    if (start_y != 0)
+        line = slice_buffer_get_line(sb, ((start_y - 1) * b->stride_line) + b->buf_y_offset) + b->buf_x_offset;
+
+    for(y=start_y; y<end_y; y++){
+        prev = line;
+//        line = slice_buffer_get_line_from_address(sb, src + (y * stride));
+        line = slice_buffer_get_line(sb, (y * b->stride_line) + b->buf_y_offset) + b->buf_x_offset;
+        for(x=0; x<w; x++){
+            if(x){
+                if(use_median){
+                    if(y && x+1<w) line[x] += mid_pred(line[x - 1], prev[x], prev[x + 1]);
+                    else  line[x] += line[x - 1];
+                }else{
+                    if(y) line[x] += mid_pred(line[x - 1], prev[x], line[x - 1] + prev[x] - prev[x - 1]);
+                    else  line[x] += line[x - 1];
+                }
+            }else{
+                if(y) line[x] += prev[x];
+            }
+        }
+    }
+}
+
+static void decode_qlogs(SnowContext *s){
+    int plane_index, level, orientation;
+
+    for(plane_index=0; plane_index<3; plane_index++){
+        for(level=0; level<s->spatial_decomposition_count; level++){
+            for(orientation=level ? 1:0; orientation<4; orientation++){
+                int q;
+                if     (plane_index==2) q= s->plane[1].band[level][orientation].qlog;
+                else if(orientation==2) q= s->plane[plane_index].band[level][1].qlog;
+                else                    q= get_symbol(&s->c, s->header_state, 1);
+                s->plane[plane_index].band[level][orientation].qlog= q;
+            }
+        }
+    }
+}
+
+#define GET_S(dst, check) \
+    tmp= get_symbol(&s->c, s->header_state, 0);\
+    if(!(check)){\
+        av_log(s->avctx, AV_LOG_ERROR, "Error " #dst " is %d\n", tmp);\
+        return -1;\
+    }\
+    dst= tmp;
+
+static int decode_header(SnowContext *s){
+    int plane_index, tmp;
+    uint8_t kstate[32];
+
+    memset(kstate, MID_STATE, sizeof(kstate));
+
+    s->keyframe= get_rac(&s->c, kstate);
+    if(s->keyframe || s->always_reset){
+        ff_snow_reset_contexts(s);
+        s->spatial_decomposition_type=
+        s->qlog=
+        s->qbias=
+        s->mv_scale=
+        s->block_max_depth= 0;
+    }
+    if(s->keyframe){
+        GET_S(s->version, tmp <= 0U)
+        s->always_reset= get_rac(&s->c, s->header_state);
+        s->temporal_decomposition_type= get_symbol(&s->c, s->header_state, 0);
+        s->temporal_decomposition_count= get_symbol(&s->c, s->header_state, 0);
+        GET_S(s->spatial_decomposition_count, 0 < tmp && tmp <= MAX_DECOMPOSITIONS)
+        s->colorspace_type= get_symbol(&s->c, s->header_state, 0);
+        s->chroma_h_shift= get_symbol(&s->c, s->header_state, 0);
+        s->chroma_v_shift= get_symbol(&s->c, s->header_state, 0);
+        s->spatial_scalability= get_rac(&s->c, s->header_state);
+//        s->rate_scalability= get_rac(&s->c, s->header_state);
+        GET_S(s->max_ref_frames, tmp < (unsigned)MAX_REF_FRAMES)
+        s->max_ref_frames++;
+
+        decode_qlogs(s);
+    }
+
+    if(!s->keyframe){
+        if(get_rac(&s->c, s->header_state)){
+            for(plane_index=0; plane_index<2; plane_index++){
+                int htaps, i, sum=0;
+                Plane *p= &s->plane[plane_index];
+                p->diag_mc= get_rac(&s->c, s->header_state);
+                htaps= get_symbol(&s->c, s->header_state, 0)*2 + 2;
+                if((unsigned)htaps > HTAPS_MAX || htaps==0)
+                    return -1;
+                p->htaps= htaps;
+                for(i= htaps/2; i; i--){
+                    p->hcoeff[i]= get_symbol(&s->c, s->header_state, 0) * (1-2*(i&1));
+                    sum += p->hcoeff[i];
+                }
+                p->hcoeff[0]= 32-sum;
+            }
+            s->plane[2].diag_mc= s->plane[1].diag_mc;
+            s->plane[2].htaps  = s->plane[1].htaps;
+            memcpy(s->plane[2].hcoeff, s->plane[1].hcoeff, sizeof(s->plane[1].hcoeff));
+        }
+        if(get_rac(&s->c, s->header_state)){
+            GET_S(s->spatial_decomposition_count, 0 < tmp && tmp <= MAX_DECOMPOSITIONS)
+            decode_qlogs(s);
+        }
+    }
+
+    s->spatial_decomposition_type+= get_symbol(&s->c, s->header_state, 1);
+    if(s->spatial_decomposition_type > 1U){
+        av_log(s->avctx, AV_LOG_ERROR, "spatial_decomposition_type %d not supported", s->spatial_decomposition_type);
+        return -1;
+    }
+    if(FFMIN(s->avctx-> width>>s->chroma_h_shift,
+             s->avctx->height>>s->chroma_v_shift) >> (s->spatial_decomposition_count-1) <= 0){
+        av_log(s->avctx, AV_LOG_ERROR, "spatial_decomposition_count %d too large for size", s->spatial_decomposition_count);
+        return -1;
+    }
+
+    s->qlog           += get_symbol(&s->c, s->header_state, 1);
+    s->mv_scale       += get_symbol(&s->c, s->header_state, 1);
+    s->qbias          += get_symbol(&s->c, s->header_state, 1);
+    s->block_max_depth+= get_symbol(&s->c, s->header_state, 1);
+    if(s->block_max_depth > 1 || s->block_max_depth < 0){
+        av_log(s->avctx, AV_LOG_ERROR, "block_max_depth= %d is too large", s->block_max_depth);
+        s->block_max_depth= 0;
+        return -1;
+    }
+
+    return 0;
+}
+
+static av_cold int decode_init(AVCodecContext *avctx)
+{
+    avctx->pix_fmt= PIX_FMT_YUV420P;
+
+    ff_snow_common_init(avctx);
+
+    return 0;
+}
+
+static void decode_blocks(SnowContext *s){
+    int x, y;
+    int w= s->b_width;
+    int h= s->b_height;
+
+    for(y=0; y<h; y++){
+        for(x=0; x<w; x++){
+            decode_q_branch(s, 0, x, y);
+        }
+    }
+}
+
+static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, AVPacket *avpkt){
+    const uint8_t *buf = avpkt->data;
+    int buf_size = avpkt->size;
+    SnowContext *s = avctx->priv_data;
+    RangeCoder * const c= &s->c;
+    int bytes_read;
+    AVFrame *picture = data;
+    int level, orientation, plane_index;
+
+    ff_init_range_decoder(c, buf, buf_size);
+    ff_build_rac_states(c, 0.05*(1LL<<32), 256-8);
+
+    s->current_picture.pict_type= AV_PICTURE_TYPE_I; //FIXME I vs. P
+    if(decode_header(s)<0)
+        return -1;
+    ff_snow_common_init_after_header(avctx);
+
+    // realloc slice buffer for the case that spatial_decomposition_count changed
+    ff_slice_buffer_destroy(&s->sb);
+    ff_slice_buffer_init(&s->sb, s->plane[0].height, (MB_SIZE >> s->block_max_depth) + s->spatial_decomposition_count * 8 + 1, s->plane[0].width, s->spatial_idwt_buffer);
+
+    for(plane_index=0; plane_index<3; plane_index++){
+        Plane *p= &s->plane[plane_index];
+        p->fast_mc= p->diag_mc && p->htaps==6 && p->hcoeff[0]==40
+                                              && p->hcoeff[1]==-10
+                                              && p->hcoeff[2]==2;
+    }
+
+    ff_snow_alloc_blocks(s);
+
+    if(ff_snow_frame_start(s) < 0)
+        return -1;
+    //keyframe flag duplication mess FIXME
+    if(avctx->debug&FF_DEBUG_PICT_INFO)
+        av_log(avctx, AV_LOG_ERROR, "keyframe:%d qlog:%d\n", s->keyframe, s->qlog);
+
+    decode_blocks(s);
+
+    for(plane_index=0; plane_index<3; plane_index++){
+        Plane *p= &s->plane[plane_index];
+        int w= p->width;
+        int h= p->height;
+        int x, y;
+        int decode_state[MAX_DECOMPOSITIONS][4][1]; /* Stored state info for unpack_coeffs. 1 variable per instance. */
+
+        if(s->avctx->debug&2048){
+            memset(s->spatial_dwt_buffer, 0, sizeof(DWTELEM)*w*h);
+            predict_plane(s, s->spatial_idwt_buffer, plane_index, 1);
+
+            for(y=0; y<h; y++){
+                for(x=0; x<w; x++){
+                    int v= s->current_picture.data[plane_index][y*s->current_picture.linesize[plane_index] + x];
+                    s->mconly_picture.data[plane_index][y*s->mconly_picture.linesize[plane_index] + x]= v;
+                }
+            }
+        }
+
+        {
+        for(level=0; level<s->spatial_decomposition_count; level++){
+            for(orientation=level ? 1 : 0; orientation<4; orientation++){
+                SubBand *b= &p->band[level][orientation];
+                unpack_coeffs(s, b, b->parent, orientation);
+            }
+        }
+        }
+
+        {
+        const int mb_h= s->b_height << s->block_max_depth;
+        const int block_size = MB_SIZE >> s->block_max_depth;
+        const int block_w    = plane_index ? block_size/2 : block_size;
+        int mb_y;
+        DWTCompose cs[MAX_DECOMPOSITIONS];
+        int yd=0, yq=0;
+        int y;
+        int end_y;
+
+        ff_spatial_idwt_buffered_init(cs, &s->sb, w, h, 1, s->spatial_decomposition_type, s->spatial_decomposition_count);
+        for(mb_y=0; mb_y<=mb_h; mb_y++){
+
+            int slice_starty = block_w*mb_y;
+            int slice_h = block_w*(mb_y+1);
+            if (!(s->keyframe || s->avctx->debug&512)){
+                slice_starty = FFMAX(0, slice_starty - (block_w >> 1));
+                slice_h -= (block_w >> 1);
+            }
+
+            for(level=0; level<s->spatial_decomposition_count; level++){
+                for(orientation=level ? 1 : 0; orientation<4; orientation++){
+                    SubBand *b= &p->band[level][orientation];
+                    int start_y;
+                    int end_y;
+                    int our_mb_start = mb_y;
+                    int our_mb_end = (mb_y + 1);
+                    const int extra= 3;
+                    start_y = (mb_y ? ((block_w * our_mb_start) >> (s->spatial_decomposition_count - level)) + s->spatial_decomposition_count - level + extra: 0);
+                    end_y = (((block_w * our_mb_end) >> (s->spatial_decomposition_count - level)) + s->spatial_decomposition_count - level + extra);
+                    if (!(s->keyframe || s->avctx->debug&512)){
+                        start_y = FFMAX(0, start_y - (block_w >> (1+s->spatial_decomposition_count - level)));
+                        end_y = FFMAX(0, end_y - (block_w >> (1+s->spatial_decomposition_count - level)));
+                    }
+                    start_y = FFMIN(b->height, start_y);
+                    end_y = FFMIN(b->height, end_y);
+
+                    if (start_y != end_y){
+                        if (orientation == 0){
+                            SubBand * correlate_band = &p->band[0][0];
+                            int correlate_end_y = FFMIN(b->height, end_y + 1);
+                            int correlate_start_y = FFMIN(b->height, (start_y ? start_y + 1 : 0));
+                            decode_subband_slice_buffered(s, correlate_band, &s->sb, correlate_start_y, correlate_end_y, decode_state[0][0]);
+                            correlate_slice_buffered(s, &s->sb, correlate_band, correlate_band->ibuf, correlate_band->stride, 1, 0, correlate_start_y, correlate_end_y);
+                            dequantize_slice_buffered(s, &s->sb, correlate_band, correlate_band->ibuf, correlate_band->stride, start_y, end_y);
+                        }
+                        else
+                            decode_subband_slice_buffered(s, b, &s->sb, start_y, end_y, decode_state[level][orientation]);
+                    }
+                }
+            }
+
+            for(; yd<slice_h; yd+=4){
+                ff_spatial_idwt_buffered_slice(&s->dwt, cs, &s->sb, w, h, 1, s->spatial_decomposition_type, s->spatial_decomposition_count, yd);
+            }
+
+            if(s->qlog == LOSSLESS_QLOG){
+                for(; yq<slice_h && yq<h; yq++){
+                    IDWTELEM * line = slice_buffer_get_line(&s->sb, yq);
+                    for(x=0; x<w; x++){
+                        line[x] <<= FRAC_BITS;
+                    }
+                }
+            }
+
+            predict_slice_buffered(s, &s->sb, s->spatial_idwt_buffer, plane_index, 1, mb_y);
+
+            y = FFMIN(p->height, slice_starty);
+            end_y = FFMIN(p->height, slice_h);
+            while(y < end_y)
+                ff_slice_buffer_release(&s->sb, y++);
+        }
+
+        ff_slice_buffer_flush(&s->sb);
+        }
+
+    }
+
+    emms_c();
+
+    ff_snow_release_buffer(avctx);
+
+    if(!(s->avctx->debug&2048))
+        *picture= s->current_picture;
+    else
+        *picture= s->mconly_picture;
+
+    *data_size = sizeof(AVFrame);
+
+    bytes_read= c->bytestream - c->bytestream_start;
+    if(bytes_read ==0) av_log(s->avctx, AV_LOG_ERROR, "error at end of frame\n"); //FIXME
+
+    return bytes_read;
+}
+
+static av_cold int decode_end(AVCodecContext *avctx)
+{
+    SnowContext *s = avctx->priv_data;
+
+    ff_slice_buffer_destroy(&s->sb);
+
+    ff_snow_common_end(s);
+
+    return 0;
+}
+
+AVCodec ff_snow_decoder = {
+    .name           = "snow",
+    .type           = AVMEDIA_TYPE_VIDEO,
+    .id             = CODEC_ID_SNOW,
+    .priv_data_size = sizeof(SnowContext),
+    .init           = decode_init,
+    .close          = decode_end,
+    .decode         = decode_frame,
+    .capabilities   = CODEC_CAP_DR1 /*| CODEC_CAP_DRAW_HORIZ_BAND*/,
+    .long_name = NULL_IF_CONFIG_SMALL("Snow"),
+};
diff --git a/libavcodec/snowenc.c b/libavcodec/snowenc.c
new file mode 100644
index 0000000..4926eef
--- /dev/null
+++ b/libavcodec/snowenc.c
@@ -0,0 +1,1915 @@
+/*
+ * Copyright (C) 2004 Michael Niedermayer <michaelni at gmx.at>
+ *
+ * This file is part of Libav.
+ *
+ * Libav is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * Libav is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with Libav; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "libavutil/intmath.h"
+#include "libavutil/log.h"
+#include "libavutil/opt.h"
+#include "avcodec.h"
+#include "dsputil.h"
+#include "dwt.h"
+#include "snow.h"
+
+#include "rangecoder.h"
+#include "mathops.h"
+
+#include "mpegvideo.h"
+#include "h263.h"
+
+#undef NDEBUG
+#include <assert.h>
+
+#define QUANTIZE2 0
+
+#if QUANTIZE2==1
+#define Q2_STEP 8
+
+static void find_sse(SnowContext *s, Plane *p, int *score, int score_stride, IDWTELEM *r0, IDWTELEM *r1, int level, int orientation){
+    SubBand *b= &p->band[level][orientation];
+    int x, y;
+    int xo=0;
+    int yo=0;
+    int step= 1 << (s->spatial_decomposition_count - level);
+
+    if(orientation&1)
+        xo= step>>1;
+    if(orientation&2)
+        yo= step>>1;
+
+    //FIXME bias for nonzero ?
+    //FIXME optimize
+    memset(score, 0, sizeof(*score)*score_stride*((p->height + Q2_STEP-1)/Q2_STEP));
+    for(y=0; y<p->height; y++){
+        for(x=0; x<p->width; x++){
+            int sx= (x-xo + step/2) / step / Q2_STEP;
+            int sy= (y-yo + step/2) / step / Q2_STEP;
+            int v= r0[x + y*p->width] - r1[x + y*p->width];
+            assert(sx>=0 && sy>=0 && sx < score_stride);
+            v= ((v+8)>>4)<<4;
+            score[sx + sy*score_stride] += v*v;
+            assert(score[sx + sy*score_stride] >= 0);
+        }
+    }
+}
+
+static void dequantize_all(SnowContext *s, Plane *p, IDWTELEM *buffer, int width, int height){
+    int level, orientation;
+
+    for(level=0; level<s->spatial_decomposition_count; level++){
+        for(orientation=level ? 1 : 0; orientation<4; orientation++){
+            SubBand *b= &p->band[level][orientation];
+            IDWTELEM *dst= buffer + (b->ibuf - s->spatial_idwt_buffer);
+
+            dequantize(s, b, dst, b->stride);
+        }
+    }
+}
+
+static void dwt_quantize(SnowContext *s, Plane *p, DWTELEM *buffer, int width, int height, int stride, int type){
+    int level, orientation, ys, xs, x, y, pass;
+    IDWTELEM best_dequant[height * stride];
+    IDWTELEM idwt2_buffer[height * stride];
+    const int score_stride= (width + 10)/Q2_STEP;
+    int best_score[(width + 10)/Q2_STEP * (height + 10)/Q2_STEP]; //FIXME size
+    int score[(width + 10)/Q2_STEP * (height + 10)/Q2_STEP]; //FIXME size
+    int threshold= (s->m.lambda * s->m.lambda) >> 6;
+
+    //FIXME pass the copy cleanly ?
+
+//    memcpy(dwt_buffer, buffer, height * stride * sizeof(DWTELEM));
+    ff_spatial_dwt(buffer, width, height, stride, type, s->spatial_decomposition_count);
+
+    for(level=0; level<s->spatial_decomposition_count; level++){
+        for(orientation=level ? 1 : 0; orientation<4; orientation++){
+            SubBand *b= &p->band[level][orientation];
+            IDWTELEM *dst= best_dequant + (b->ibuf - s->spatial_idwt_buffer);
+             DWTELEM *src=       buffer + (b-> buf - s->spatial_dwt_buffer);
+            assert(src == b->buf); // code does not depend on this but it is true currently
+
+            quantize(s, b, dst, src, b->stride, s->qbias);
+        }
+    }
+    for(pass=0; pass<1; pass++){
+        if(s->qbias == 0) //keyframe
+            continue;
+        for(level=0; level<s->spatial_decomposition_count; level++){
+            for(orientation=level ? 1 : 0; orientation<4; orientation++){
+                SubBand *b= &p->band[level][orientation];
+                IDWTELEM *dst= idwt2_buffer + (b->ibuf - s->spatial_idwt_buffer);
+                IDWTELEM *best_dst= best_dequant + (b->ibuf - s->spatial_idwt_buffer);
+
+                for(ys= 0; ys<Q2_STEP; ys++){
+                    for(xs= 0; xs<Q2_STEP; xs++){
+                        memcpy(idwt2_buffer, best_dequant, height * stride * sizeof(IDWTELEM));
+                        dequantize_all(s, p, idwt2_buffer, width, height);
+                        ff_spatial_idwt(idwt2_buffer, width, height, stride, type, s->spatial_decomposition_count);
+                        find_sse(s, p, best_score, score_stride, idwt2_buffer, s->spatial_idwt_buffer, level, orientation);
+                        memcpy(idwt2_buffer, best_dequant, height * stride * sizeof(IDWTELEM));
+                        for(y=ys; y<b->height; y+= Q2_STEP){
+                            for(x=xs; x<b->width; x+= Q2_STEP){
+                                if(dst[x + y*b->stride]<0) dst[x + y*b->stride]++;
+                                if(dst[x + y*b->stride]>0) dst[x + y*b->stride]--;
+                                //FIXME try more than just --
+                            }
+                        }
+                        dequantize_all(s, p, idwt2_buffer, width, height);
+                        ff_spatial_idwt(idwt2_buffer, width, height, stride, type, s->spatial_decomposition_count);
+                        find_sse(s, p, score, score_stride, idwt2_buffer, s->spatial_idwt_buffer, level, orientation);
+                        for(y=ys; y<b->height; y+= Q2_STEP){
+                            for(x=xs; x<b->width; x+= Q2_STEP){
+                                int score_idx= x/Q2_STEP + (y/Q2_STEP)*score_stride;
+                                if(score[score_idx] <= best_score[score_idx] + threshold){
+                                    best_score[score_idx]= score[score_idx];
+                                    if(best_dst[x + y*b->stride]<0) best_dst[x + y*b->stride]++;
+                                    if(best_dst[x + y*b->stride]>0) best_dst[x + y*b->stride]--;
+                                    //FIXME copy instead
+                                }
+                            }
+                        }
+                    }
+                }
+            }
+        }
+    }
+    memcpy(s->spatial_idwt_buffer, best_dequant, height * stride * sizeof(IDWTELEM)); //FIXME work with that directly instead of copy at the end
+}
+
+#endif /* QUANTIZE2==1 */
+
+#if CONFIG_SNOW_ENCODER
+static av_cold int encode_init(AVCodecContext *avctx)
+{
+    SnowContext *s = avctx->priv_data;
+    int plane_index;
+
+    if(avctx->strict_std_compliance > FF_COMPLIANCE_EXPERIMENTAL){
+        av_log(avctx, AV_LOG_ERROR, "This codec is under development, files encoded with it may not be decodable with future versions!!!\n"
+               "Use vstrict=-2 / -strict -2 to use it anyway.\n");
+        return -1;
+    }
+
+    if(avctx->prediction_method == DWT_97
+       && (avctx->flags & CODEC_FLAG_QSCALE)
+       && avctx->global_quality == 0){
+        av_log(avctx, AV_LOG_ERROR, "The 9/7 wavelet is incompatible with lossless mode.\n");
+        return -1;
+    }
+
+    s->spatial_decomposition_type= avctx->prediction_method; //FIXME add decorrelator type r transform_type
+
+    s->mv_scale       = (avctx->flags & CODEC_FLAG_QPEL) ? 2 : 4;
+    s->block_max_depth= (avctx->flags & CODEC_FLAG_4MV ) ? 1 : 0;
+
+    for(plane_index=0; plane_index<3; plane_index++){
+        s->plane[plane_index].diag_mc= 1;
+        s->plane[plane_index].htaps= 6;
+        s->plane[plane_index].hcoeff[0]=  40;
+        s->plane[plane_index].hcoeff[1]= -10;
+        s->plane[plane_index].hcoeff[2]=   2;
+        s->plane[plane_index].fast_mc= 1;
+    }
+
+    ff_snow_common_init(avctx);
+    ff_snow_alloc_blocks(s);
+
+    s->version=0;
+
+    s->m.avctx   = avctx;
+    s->m.flags   = avctx->flags;
+    s->m.bit_rate= avctx->bit_rate;
+
+    s->m.me.temp      =
+    s->m.me.scratchpad= av_mallocz((avctx->width+64)*2*16*2*sizeof(uint8_t));
+    s->m.me.map       = av_mallocz(ME_MAP_SIZE*sizeof(uint32_t));
+    s->m.me.score_map = av_mallocz(ME_MAP_SIZE*sizeof(uint32_t));
+    s->m.obmc_scratchpad= av_mallocz(MB_SIZE*MB_SIZE*12*sizeof(uint32_t));
+    h263_encode_init(&s->m); //mv_penalty
+
+    s->max_ref_frames = FFMAX(FFMIN(avctx->refs, MAX_REF_FRAMES), 1);
+
+    if(avctx->flags&CODEC_FLAG_PASS1){
+        if(!avctx->stats_out)
+            avctx->stats_out = av_mallocz(256);
+    }
+    if((avctx->flags&CODEC_FLAG_PASS2) || !(avctx->flags&CODEC_FLAG_QSCALE)){
+        if(ff_rate_control_init(&s->m) < 0)
+            return -1;
+    }
+    s->pass1_rc= !(avctx->flags & (CODEC_FLAG_QSCALE|CODEC_FLAG_PASS2));
+
+    avctx->coded_frame= &s->current_picture;
+    switch(avctx->pix_fmt){
+//    case PIX_FMT_YUV444P:
+//    case PIX_FMT_YUV422P:
+    case PIX_FMT_YUV420P:
+    case PIX_FMT_GRAY8:
+//    case PIX_FMT_YUV411P:
+//    case PIX_FMT_YUV410P:
+        s->colorspace_type= 0;
+        break;
+/*    case PIX_FMT_RGB32:
+        s->colorspace= 1;
+        break;*/
+    default:
+        av_log(avctx, AV_LOG_ERROR, "pixel format not supported\n");
+        return -1;
+    }
+//    avcodec_get_chroma_sub_sample(avctx->pix_fmt, &s->chroma_h_shift, &s->chroma_v_shift);
+    s->chroma_h_shift= 1;
+    s->chroma_v_shift= 1;
+
+    ff_set_cmp(&s->dsp, s->dsp.me_cmp, s->avctx->me_cmp);
+    ff_set_cmp(&s->dsp, s->dsp.me_sub_cmp, s->avctx->me_sub_cmp);
+
+    s->avctx->get_buffer(s->avctx, &s->input_picture);
+
+    if(s->avctx->me_method == ME_ITER){
+        int i;
+        int size= s->b_width * s->b_height << 2*s->block_max_depth;
+        for(i=0; i<s->max_ref_frames; i++){
+            s->ref_mvs[i]= av_mallocz(size*sizeof(int16_t[2]));
+            s->ref_scores[i]= av_mallocz(size*sizeof(uint32_t));
+        }
+    }
+
+    return 0;
+}
+
+//near copy & paste from dsputil, FIXME
+static int pix_sum(uint8_t * pix, int line_size, int w)
+{
+    int s, i, j;
+
+    s = 0;
+    for (i = 0; i < w; i++) {
+        for (j = 0; j < w; j++) {
+            s += pix[0];
+            pix ++;
+        }
+        pix += line_size - w;
+    }
+    return s;
+}
+
+//near copy & paste from dsputil, FIXME
+static int pix_norm1(uint8_t * pix, int line_size, int w)
+{
+    int s, i, j;
+    uint32_t *sq = ff_squareTbl + 256;
+
+    s = 0;
+    for (i = 0; i < w; i++) {
+        for (j = 0; j < w; j ++) {
+            s += sq[pix[0]];
+            pix ++;
+        }
+        pix += line_size - w;
+    }
+    return s;
+}
+
+//FIXME copy&paste
+#define P_LEFT P[1]
+#define P_TOP P[2]
+#define P_TOPRIGHT P[3]
+#define P_MEDIAN P[4]
+#define P_MV1 P[9]
+#define FLAG_QPEL   1 //must be 1
+
+static int encode_q_branch(SnowContext *s, int level, int x, int y){
+    uint8_t p_buffer[1024];
+    uint8_t i_buffer[1024];
+    uint8_t p_state[sizeof(s->block_state)];
+    uint8_t i_state[sizeof(s->block_state)];
+    RangeCoder pc, ic;
+    uint8_t *pbbak= s->c.bytestream;
+    uint8_t *pbbak_start= s->c.bytestream_start;
+    int score, score2, iscore, i_len, p_len, block_s, sum, base_bits;
+    const int w= s->b_width  << s->block_max_depth;
+    const int h= s->b_height << s->block_max_depth;
+    const int rem_depth= s->block_max_depth - level;
+    const int index= (x + y*w) << rem_depth;
+    const int block_w= 1<<(LOG2_MB_SIZE - level);
+    int trx= (x+1)<<rem_depth;
+    int try= (y+1)<<rem_depth;
+    const BlockNode *left  = x ? &s->block[index-1] : &null_block;
+    const BlockNode *top   = y ? &s->block[index-w] : &null_block;
+    const BlockNode *right = trx<w ? &s->block[index+1] : &null_block;
+    const BlockNode *bottom= try<h ? &s->block[index+w] : &null_block;
+    const BlockNode *tl    = y && x ? &s->block[index-w-1] : left;
+    const BlockNode *tr    = y && trx<w && ((x&1)==0 || level==0) ? &s->block[index-w+(1<<rem_depth)] : tl; //FIXME use lt
+    int pl = left->color[0];
+    int pcb= left->color[1];
+    int pcr= left->color[2];
+    int pmx, pmy;
+    int mx=0, my=0;
+    int l,cr,cb;
+    const int stride= s->current_picture.linesize[0];
+    const int uvstride= s->current_picture.linesize[1];
+    uint8_t *current_data[3]= { s->input_picture.data[0] + (x + y*  stride)*block_w,
+                                s->input_picture.data[1] + (x + y*uvstride)*block_w/2,
+                                s->input_picture.data[2] + (x + y*uvstride)*block_w/2};
+    int P[10][2];
+    int16_t last_mv[3][2];
+    int qpel= !!(s->avctx->flags & CODEC_FLAG_QPEL); //unused
+    const int shift= 1+qpel;
+    MotionEstContext *c= &s->m.me;
+    int ref_context= av_log2(2*left->ref) + av_log2(2*top->ref);
+    int mx_context= av_log2(2*FFABS(left->mx - top->mx));
+    int my_context= av_log2(2*FFABS(left->my - top->my));
+    int s_context= 2*left->level + 2*top->level + tl->level + tr->level;
+    int ref, best_ref, ref_score, ref_mx, ref_my;
+
+    assert(sizeof(s->block_state) >= 256);
+    if(s->keyframe){
+        set_blocks(s, level, x, y, pl, pcb, pcr, 0, 0, 0, BLOCK_INTRA);
+        return 0;
+    }
+
+//    clip predictors / edge ?
+
+    P_LEFT[0]= left->mx;
+    P_LEFT[1]= left->my;
+    P_TOP [0]= top->mx;
+    P_TOP [1]= top->my;
+    P_TOPRIGHT[0]= tr->mx;
+    P_TOPRIGHT[1]= tr->my;
+
+    last_mv[0][0]= s->block[index].mx;
+    last_mv[0][1]= s->block[index].my;
+    last_mv[1][0]= right->mx;
+    last_mv[1][1]= right->my;
+    last_mv[2][0]= bottom->mx;
+    last_mv[2][1]= bottom->my;
+
+    s->m.mb_stride=2;
+    s->m.mb_x=
+    s->m.mb_y= 0;
+    c->skip= 0;
+
+    assert(c->  stride ==   stride);
+    assert(c->uvstride == uvstride);
+
+    c->penalty_factor    = get_penalty_factor(s->lambda, s->lambda2, c->avctx->me_cmp);
+    c->sub_penalty_factor= get_penalty_factor(s->lambda, s->lambda2, c->avctx->me_sub_cmp);
+    c->mb_penalty_factor = get_penalty_factor(s->lambda, s->lambda2, c->avctx->mb_cmp);
+    c->current_mv_penalty= c->mv_penalty[s->m.f_code=1] + MAX_MV;
+
+    c->xmin = - x*block_w - 16+3;
+    c->ymin = - y*block_w - 16+3;
+    c->xmax = - (x+1)*block_w + (w<<(LOG2_MB_SIZE - s->block_max_depth)) + 16-3;
+    c->ymax = - (y+1)*block_w + (h<<(LOG2_MB_SIZE - s->block_max_depth)) + 16-3;
+
+    if(P_LEFT[0]     > (c->xmax<<shift)) P_LEFT[0]    = (c->xmax<<shift);
+    if(P_LEFT[1]     > (c->ymax<<shift)) P_LEFT[1]    = (c->ymax<<shift);
+    if(P_TOP[0]      > (c->xmax<<shift)) P_TOP[0]     = (c->xmax<<shift);
+    if(P_TOP[1]      > (c->ymax<<shift)) P_TOP[1]     = (c->ymax<<shift);
+    if(P_TOPRIGHT[0] < (c->xmin<<shift)) P_TOPRIGHT[0]= (c->xmin<<shift);
+    if(P_TOPRIGHT[0] > (c->xmax<<shift)) P_TOPRIGHT[0]= (c->xmax<<shift); //due to pmx no clip
+    if(P_TOPRIGHT[1] > (c->ymax<<shift)) P_TOPRIGHT[1]= (c->ymax<<shift);
+
+    P_MEDIAN[0]= mid_pred(P_LEFT[0], P_TOP[0], P_TOPRIGHT[0]);
+    P_MEDIAN[1]= mid_pred(P_LEFT[1], P_TOP[1], P_TOPRIGHT[1]);
+
+    if (!y) {
+        c->pred_x= P_LEFT[0];
+        c->pred_y= P_LEFT[1];
+    } else {
+        c->pred_x = P_MEDIAN[0];
+        c->pred_y = P_MEDIAN[1];
+    }
+
+    score= INT_MAX;
+    best_ref= 0;
+    for(ref=0; ref<s->ref_frames; ref++){
+        init_ref(c, current_data, s->last_picture[ref].data, NULL, block_w*x, block_w*y, 0);
+
+        ref_score= ff_epzs_motion_search(&s->m, &ref_mx, &ref_my, P, 0, /*ref_index*/ 0, last_mv,
+                                         (1<<16)>>shift, level-LOG2_MB_SIZE+4, block_w);
+
+        assert(ref_mx >= c->xmin);
+        assert(ref_mx <= c->xmax);
+        assert(ref_my >= c->ymin);
+        assert(ref_my <= c->ymax);
+
+        ref_score= c->sub_motion_search(&s->m, &ref_mx, &ref_my, ref_score, 0, 0, level-LOG2_MB_SIZE+4, block_w);
+        ref_score= ff_get_mb_score(&s->m, ref_mx, ref_my, 0, 0, level-LOG2_MB_SIZE+4, block_w, 0);
+        ref_score+= 2*av_log2(2*ref)*c->penalty_factor;
+        if(s->ref_mvs[ref]){
+            s->ref_mvs[ref][index][0]= ref_mx;
+            s->ref_mvs[ref][index][1]= ref_my;
+            s->ref_scores[ref][index]= ref_score;
+        }
+        if(score > ref_score){
+            score= ref_score;
+            best_ref= ref;
+            mx= ref_mx;
+            my= ref_my;
+        }
+    }
+    //FIXME if mb_cmp != SSE then intra cannot be compared currently and mb_penalty vs. lambda2
+
+  //  subpel search
+    base_bits= get_rac_count(&s->c) - 8*(s->c.bytestream - s->c.bytestream_start);
+    pc= s->c;
+    pc.bytestream_start=
+    pc.bytestream= p_buffer; //FIXME end/start? and at the other stoo
+    memcpy(p_state, s->block_state, sizeof(s->block_state));
+
+    if(level!=s->block_max_depth)
+        put_rac(&pc, &p_state[4 + s_context], 1);
+    put_rac(&pc, &p_state[1 + left->type + top->type], 0);
+    if(s->ref_frames > 1)
+        put_symbol(&pc, &p_state[128 + 1024 + 32*ref_context], best_ref, 0);
+    pred_mv(s, &pmx, &pmy, best_ref, left, top, tr);
+    put_symbol(&pc, &p_state[128 + 32*(mx_context + 16*!!best_ref)], mx - pmx, 1);
+    put_symbol(&pc, &p_state[128 + 32*(my_context + 16*!!best_ref)], my - pmy, 1);
+    p_len= pc.bytestream - pc.bytestream_start;
+    score += (s->lambda2*(get_rac_count(&pc)-base_bits))>>FF_LAMBDA_SHIFT;
+
+    block_s= block_w*block_w;
+    sum = pix_sum(current_data[0], stride, block_w);
+    l= (sum + block_s/2)/block_s;
+    iscore = pix_norm1(current_data[0], stride, block_w) - 2*l*sum + l*l*block_s;
+
+    block_s= block_w*block_w>>2;
+    sum = pix_sum(current_data[1], uvstride, block_w>>1);
+    cb= (sum + block_s/2)/block_s;
+//    iscore += pix_norm1(&current_mb[1][0], uvstride, block_w>>1) - 2*cb*sum + cb*cb*block_s;
+    sum = pix_sum(current_data[2], uvstride, block_w>>1);
+    cr= (sum + block_s/2)/block_s;
+//    iscore += pix_norm1(&current_mb[2][0], uvstride, block_w>>1) - 2*cr*sum + cr*cr*block_s;
+
+    ic= s->c;
+    ic.bytestream_start=
+    ic.bytestream= i_buffer; //FIXME end/start? and at the other stoo
+    memcpy(i_state, s->block_state, sizeof(s->block_state));
+    if(level!=s->block_max_depth)
+        put_rac(&ic, &i_state[4 + s_context], 1);
+    put_rac(&ic, &i_state[1 + left->type + top->type], 1);
+    put_symbol(&ic, &i_state[32],  l-pl , 1);
+    put_symbol(&ic, &i_state[64], cb-pcb, 1);
+    put_symbol(&ic, &i_state[96], cr-pcr, 1);
+    i_len= ic.bytestream - ic.bytestream_start;
+    iscore += (s->lambda2*(get_rac_count(&ic)-base_bits))>>FF_LAMBDA_SHIFT;
+
+//    assert(score==256*256*256*64-1);
+    assert(iscore < 255*255*256 + s->lambda2*10);
+    assert(iscore >= 0);
+    assert(l>=0 && l<=255);
+    assert(pl>=0 && pl<=255);
+
+    if(level==0){
+        int varc= iscore >> 8;
+        int vard= score >> 8;
+        if (vard <= 64 || vard < varc)
+            c->scene_change_score+= ff_sqrt(vard) - ff_sqrt(varc);
+        else
+            c->scene_change_score+= s->m.qscale;
+    }
+
+    if(level!=s->block_max_depth){
+        put_rac(&s->c, &s->block_state[4 + s_context], 0);
+        score2 = encode_q_branch(s, level+1, 2*x+0, 2*y+0);
+        score2+= encode_q_branch(s, level+1, 2*x+1, 2*y+0);
+        score2+= encode_q_branch(s, level+1, 2*x+0, 2*y+1);
+        score2+= encode_q_branch(s, level+1, 2*x+1, 2*y+1);
+        score2+= s->lambda2>>FF_LAMBDA_SHIFT; //FIXME exact split overhead
+
+        if(score2 < score && score2 < iscore)
+            return score2;
+    }
+
+    if(iscore < score){
+        pred_mv(s, &pmx, &pmy, 0, left, top, tr);
+        memcpy(pbbak, i_buffer, i_len);
+        s->c= ic;
+        s->c.bytestream_start= pbbak_start;
+        s->c.bytestream= pbbak + i_len;
+        set_blocks(s, level, x, y, l, cb, cr, pmx, pmy, 0, BLOCK_INTRA);
+        memcpy(s->block_state, i_state, sizeof(s->block_state));
+        return iscore;
+    }else{
+        memcpy(pbbak, p_buffer, p_len);
+        s->c= pc;
+        s->c.bytestream_start= pbbak_start;
+        s->c.bytestream= pbbak + p_len;
+        set_blocks(s, level, x, y, pl, pcb, pcr, mx, my, best_ref, 0);
+        memcpy(s->block_state, p_state, sizeof(s->block_state));
+        return score;
+    }
+}
+
+static void encode_q_branch2(SnowContext *s, int level, int x, int y){
+    const int w= s->b_width  << s->block_max_depth;
+    const int rem_depth= s->block_max_depth - level;
+    const int index= (x + y*w) << rem_depth;
+    int trx= (x+1)<<rem_depth;
+    BlockNode *b= &s->block[index];
+    const BlockNode *left  = x ? &s->block[index-1] : &null_block;
+    const BlockNode *top   = y ? &s->block[index-w] : &null_block;
+    const BlockNode *tl    = y && x ? &s->block[index-w-1] : left;
+    const BlockNode *tr    = y && trx<w && ((x&1)==0 || level==0) ? &s->block[index-w+(1<<rem_depth)] : tl; //FIXME use lt
+    int pl = left->color[0];
+    int pcb= left->color[1];
+    int pcr= left->color[2];
+    int pmx, pmy;
+    int ref_context= av_log2(2*left->ref) + av_log2(2*top->ref);
+    int mx_context= av_log2(2*FFABS(left->mx - top->mx)) + 16*!!b->ref;
+    int my_context= av_log2(2*FFABS(left->my - top->my)) + 16*!!b->ref;
+    int s_context= 2*left->level + 2*top->level + tl->level + tr->level;
+
+    if(s->keyframe){
+        set_blocks(s, level, x, y, pl, pcb, pcr, 0, 0, 0, BLOCK_INTRA);
+        return;
+    }
+
+    if(level!=s->block_max_depth){
+        if(same_block(b,b+1) && same_block(b,b+w) && same_block(b,b+w+1)){
+            put_rac(&s->c, &s->block_state[4 + s_context], 1);
+        }else{
+            put_rac(&s->c, &s->block_state[4 + s_context], 0);
+            encode_q_branch2(s, level+1, 2*x+0, 2*y+0);
+            encode_q_branch2(s, level+1, 2*x+1, 2*y+0);
+            encode_q_branch2(s, level+1, 2*x+0, 2*y+1);
+            encode_q_branch2(s, level+1, 2*x+1, 2*y+1);
+            return;
+        }
+    }
+    if(b->type & BLOCK_INTRA){
+        pred_mv(s, &pmx, &pmy, 0, left, top, tr);
+        put_rac(&s->c, &s->block_state[1 + (left->type&1) + (top->type&1)], 1);
+        put_symbol(&s->c, &s->block_state[32], b->color[0]-pl , 1);
+        put_symbol(&s->c, &s->block_state[64], b->color[1]-pcb, 1);
+        put_symbol(&s->c, &s->block_state[96], b->color[2]-pcr, 1);
+        set_blocks(s, level, x, y, b->color[0], b->color[1], b->color[2], pmx, pmy, 0, BLOCK_INTRA);
+    }else{
+        pred_mv(s, &pmx, &pmy, b->ref, left, top, tr);
+        put_rac(&s->c, &s->block_state[1 + (left->type&1) + (top->type&1)], 0);
+        if(s->ref_frames > 1)
+            put_symbol(&s->c, &s->block_state[128 + 1024 + 32*ref_context], b->ref, 0);
+        put_symbol(&s->c, &s->block_state[128 + 32*mx_context], b->mx - pmx, 1);
+        put_symbol(&s->c, &s->block_state[128 + 32*my_context], b->my - pmy, 1);
+        set_blocks(s, level, x, y, pl, pcb, pcr, b->mx, b->my, b->ref, 0);
+    }
+}
+
+static int get_dc(SnowContext *s, int mb_x, int mb_y, int plane_index){
+    int i, x2, y2;
+    Plane *p= &s->plane[plane_index];
+    const int block_size = MB_SIZE >> s->block_max_depth;
+    const int block_w    = plane_index ? block_size/2 : block_size;
+    const uint8_t *obmc  = plane_index ? obmc_tab[s->block_max_depth+1] : obmc_tab[s->block_max_depth];
+    const int obmc_stride= plane_index ? block_size : 2*block_size;
+    const int ref_stride= s->current_picture.linesize[plane_index];
+    uint8_t *src= s-> input_picture.data[plane_index];
+    IDWTELEM *dst= (IDWTELEM*)s->m.obmc_scratchpad + plane_index*block_size*block_size*4; //FIXME change to unsigned
+    const int b_stride = s->b_width << s->block_max_depth;
+    const int w= p->width;
+    const int h= p->height;
+    int index= mb_x + mb_y*b_stride;
+    BlockNode *b= &s->block[index];
+    BlockNode backup= *b;
+    int ab=0;
+    int aa=0;
+
+    b->type|= BLOCK_INTRA;
+    b->color[plane_index]= 0;
+    memset(dst, 0, obmc_stride*obmc_stride*sizeof(IDWTELEM));
+
+    for(i=0; i<4; i++){
+        int mb_x2= mb_x + (i &1) - 1;
+        int mb_y2= mb_y + (i>>1) - 1;
+        int x= block_w*mb_x2 + block_w/2;
+        int y= block_w*mb_y2 + block_w/2;
+
+        add_yblock(s, 0, NULL, dst + ((i&1)+(i>>1)*obmc_stride)*block_w, NULL, obmc,
+                    x, y, block_w, block_w, w, h, obmc_stride, ref_stride, obmc_stride, mb_x2, mb_y2, 0, 0, plane_index);
+
+        for(y2= FFMAX(y, 0); y2<FFMIN(h, y+block_w); y2++){
+            for(x2= FFMAX(x, 0); x2<FFMIN(w, x+block_w); x2++){
+                int index= x2-(block_w*mb_x - block_w/2) + (y2-(block_w*mb_y - block_w/2))*obmc_stride;
+                int obmc_v= obmc[index];
+                int d;
+                if(y<0) obmc_v += obmc[index + block_w*obmc_stride];
+                if(x<0) obmc_v += obmc[index + block_w];
+                if(y+block_w>h) obmc_v += obmc[index - block_w*obmc_stride];
+                if(x+block_w>w) obmc_v += obmc[index - block_w];
+                //FIXME precalculate this or simplify it somehow else
+
+                d = -dst[index] + (1<<(FRAC_BITS-1));
+                dst[index] = d;
+                ab += (src[x2 + y2*ref_stride] - (d>>FRAC_BITS)) * obmc_v;
+                aa += obmc_v * obmc_v; //FIXME precalculate this
+            }
+        }
+    }
+    *b= backup;
+
+    return av_clip(((ab<<LOG2_OBMC_MAX) + aa/2)/aa, 0, 255); //FIXME we should not need clipping
+}
+
+static inline int get_block_bits(SnowContext *s, int x, int y, int w){
+    const int b_stride = s->b_width << s->block_max_depth;
+    const int b_height = s->b_height<< s->block_max_depth;
+    int index= x + y*b_stride;
+    const BlockNode *b     = &s->block[index];
+    const BlockNode *left  = x ? &s->block[index-1] : &null_block;
+    const BlockNode *top   = y ? &s->block[index-b_stride] : &null_block;
+    const BlockNode *tl    = y && x ? &s->block[index-b_stride-1] : left;
+    const BlockNode *tr    = y && x+w<b_stride ? &s->block[index-b_stride+w] : tl;
+    int dmx, dmy;
+//  int mx_context= av_log2(2*FFABS(left->mx - top->mx));
+//  int my_context= av_log2(2*FFABS(left->my - top->my));
+
+    if(x<0 || x>=b_stride || y>=b_height)
+        return 0;
+/*
+1            0      0
+01X          1-2    1
+001XX        3-6    2-3
+0001XXX      7-14   4-7
+00001XXXX   15-30   8-15
+*/
+//FIXME try accurate rate
+//FIXME intra and inter predictors if surrounding blocks are not the same type
+    if(b->type & BLOCK_INTRA){
+        return 3+2*( av_log2(2*FFABS(left->color[0] - b->color[0]))
+                   + av_log2(2*FFABS(left->color[1] - b->color[1]))
+                   + av_log2(2*FFABS(left->color[2] - b->color[2])));
+    }else{
+        pred_mv(s, &dmx, &dmy, b->ref, left, top, tr);
+        dmx-= b->mx;
+        dmy-= b->my;
+        return 2*(1 + av_log2(2*FFABS(dmx)) //FIXME kill the 2* can be merged in lambda
+                    + av_log2(2*FFABS(dmy))
+                    + av_log2(2*b->ref));
+    }
+}
+
+static int get_block_rd(SnowContext *s, int mb_x, int mb_y, int plane_index, const uint8_t *obmc_edged){
+    Plane *p= &s->plane[plane_index];
+    const int block_size = MB_SIZE >> s->block_max_depth;
+    const int block_w    = plane_index ? block_size/2 : block_size;
+    const int obmc_stride= plane_index ? block_size : 2*block_size;
+    const int ref_stride= s->current_picture.linesize[plane_index];
+    uint8_t *dst= s->current_picture.data[plane_index];
+    uint8_t *src= s->  input_picture.data[plane_index];
+    IDWTELEM *pred= (IDWTELEM*)s->m.obmc_scratchpad + plane_index*block_size*block_size*4;
+    uint8_t *cur = s->scratchbuf;
+    uint8_t tmp[ref_stride*(2*MB_SIZE+HTAPS_MAX-1)];
+    const int b_stride = s->b_width << s->block_max_depth;
+    const int b_height = s->b_height<< s->block_max_depth;
+    const int w= p->width;
+    const int h= p->height;
+    int distortion;
+    int rate= 0;
+    const int penalty_factor= get_penalty_factor(s->lambda, s->lambda2, s->avctx->me_cmp);
+    int sx= block_w*mb_x - block_w/2;
+    int sy= block_w*mb_y - block_w/2;
+    int x0= FFMAX(0,-sx);
+    int y0= FFMAX(0,-sy);
+    int x1= FFMIN(block_w*2, w-sx);
+    int y1= FFMIN(block_w*2, h-sy);
+    int i,x,y;
+
+    ff_snow_pred_block(s, cur, tmp, ref_stride, sx, sy, block_w*2, block_w*2, &s->block[mb_x + mb_y*b_stride], plane_index, w, h);
+
+    for(y=y0; y<y1; y++){
+        const uint8_t *obmc1= obmc_edged + y*obmc_stride;
+        const IDWTELEM *pred1 = pred + y*obmc_stride;
+        uint8_t *cur1 = cur + y*ref_stride;
+        uint8_t *dst1 = dst + sx + (sy+y)*ref_stride;
+        for(x=x0; x<x1; x++){
+#if FRAC_BITS >= LOG2_OBMC_MAX
+            int v = (cur1[x] * obmc1[x]) << (FRAC_BITS - LOG2_OBMC_MAX);
+#else
+            int v = (cur1[x] * obmc1[x] + (1<<(LOG2_OBMC_MAX - FRAC_BITS-1))) >> (LOG2_OBMC_MAX - FRAC_BITS);
+#endif
+            v = (v + pred1[x]) >> FRAC_BITS;
+            if(v&(~255)) v= ~(v>>31);
+            dst1[x] = v;
+        }
+    }
+
+    /* copy the regions where obmc[] = (uint8_t)256 */
+    if(LOG2_OBMC_MAX == 8
+        && (mb_x == 0 || mb_x == b_stride-1)
+        && (mb_y == 0 || mb_y == b_height-1)){
+        if(mb_x == 0)
+            x1 = block_w;
+        else
+            x0 = block_w;
+        if(mb_y == 0)
+            y1 = block_w;
+        else
+            y0 = block_w;
+        for(y=y0; y<y1; y++)
+            memcpy(dst + sx+x0 + (sy+y)*ref_stride, cur + x0 + y*ref_stride, x1-x0);
+    }
+
+    if(block_w==16){
+        /* FIXME rearrange dsputil to fit 32x32 cmp functions */
+        /* FIXME check alignment of the cmp wavelet vs the encoding wavelet */
+        /* FIXME cmps overlap but do not cover the wavelet's whole support.
+         * So improving the score of one block is not strictly guaranteed
+         * to improve the score of the whole frame, thus iterative motion
+         * estimation does not always converge. */
+        if(s->avctx->me_cmp == FF_CMP_W97)
+            distortion = ff_w97_32_c(&s->m, src + sx + sy*ref_stride, dst + sx + sy*ref_stride, ref_stride, 32);
+        else if(s->avctx->me_cmp == FF_CMP_W53)
+            distortion = ff_w53_32_c(&s->m, src + sx + sy*ref_stride, dst + sx + sy*ref_stride, ref_stride, 32);
+        else{
+            distortion = 0;
+            for(i=0; i<4; i++){
+                int off = sx+16*(i&1) + (sy+16*(i>>1))*ref_stride;
+                distortion += s->dsp.me_cmp[0](&s->m, src + off, dst + off, ref_stride, 16);
+            }
+        }
+    }else{
+        assert(block_w==8);
+        distortion = s->dsp.me_cmp[0](&s->m, src + sx + sy*ref_stride, dst + sx + sy*ref_stride, ref_stride, block_w*2);
+    }
+
+    if(plane_index==0){
+        for(i=0; i<4; i++){
+/* ..RRr
+ * .RXx.
+ * rxx..
+ */
+            rate += get_block_bits(s, mb_x + (i&1) - (i>>1), mb_y + (i>>1), 1);
+        }
+        if(mb_x == b_stride-2)
+            rate += get_block_bits(s, mb_x + 1, mb_y + 1, 1);
+    }
+    return distortion + rate*penalty_factor;
+}
+
+static int get_4block_rd(SnowContext *s, int mb_x, int mb_y, int plane_index){
+    int i, y2;
+    Plane *p= &s->plane[plane_index];
+    const int block_size = MB_SIZE >> s->block_max_depth;
+    const int block_w    = plane_index ? block_size/2 : block_size;
+    const uint8_t *obmc  = plane_index ? obmc_tab[s->block_max_depth+1] : obmc_tab[s->block_max_depth];
+    const int obmc_stride= plane_index ? block_size : 2*block_size;
+    const int ref_stride= s->current_picture.linesize[plane_index];
+    uint8_t *dst= s->current_picture.data[plane_index];
+    uint8_t *src= s-> input_picture.data[plane_index];
+    //FIXME zero_dst is const but add_yblock changes dst if add is 0 (this is never the case for dst=zero_dst
+    // const has only been removed from zero_dst to suppress a warning
+    static IDWTELEM zero_dst[4096]; //FIXME
+    const int b_stride = s->b_width << s->block_max_depth;
+    const int w= p->width;
+    const int h= p->height;
+    int distortion= 0;
+    int rate= 0;
+    const int penalty_factor= get_penalty_factor(s->lambda, s->lambda2, s->avctx->me_cmp);
+
+    for(i=0; i<9; i++){
+        int mb_x2= mb_x + (i%3) - 1;
+        int mb_y2= mb_y + (i/3) - 1;
+        int x= block_w*mb_x2 + block_w/2;
+        int y= block_w*mb_y2 + block_w/2;
+
+        add_yblock(s, 0, NULL, zero_dst, dst, obmc,
+                   x, y, block_w, block_w, w, h, /*dst_stride*/0, ref_stride, obmc_stride, mb_x2, mb_y2, 1, 1, plane_index);
+
+        //FIXME find a cleaner/simpler way to skip the outside stuff
+        for(y2= y; y2<0; y2++)
+            memcpy(dst + x + y2*ref_stride, src + x + y2*ref_stride, block_w);
+        for(y2= h; y2<y+block_w; y2++)
+            memcpy(dst + x + y2*ref_stride, src + x + y2*ref_stride, block_w);
+        if(x<0){
+            for(y2= y; y2<y+block_w; y2++)
+                memcpy(dst + x + y2*ref_stride, src + x + y2*ref_stride, -x);
+        }
+        if(x+block_w > w){
+            for(y2= y; y2<y+block_w; y2++)
+                memcpy(dst + w + y2*ref_stride, src + w + y2*ref_stride, x+block_w - w);
+        }
+
+        assert(block_w== 8 || block_w==16);
+        distortion += s->dsp.me_cmp[block_w==8](&s->m, src + x + y*ref_stride, dst + x + y*ref_stride, ref_stride, block_w);
+    }
+
+    if(plane_index==0){
+        BlockNode *b= &s->block[mb_x+mb_y*b_stride];
+        int merged= same_block(b,b+1) && same_block(b,b+b_stride) && same_block(b,b+b_stride+1);
+
+/* ..RRRr
+ * .RXXx.
+ * .RXXx.
+ * rxxx.
+ */
+        if(merged)
+            rate = get_block_bits(s, mb_x, mb_y, 2);
+        for(i=merged?4:0; i<9; i++){
+            static const int dxy[9][2] = {{0,0},{1,0},{0,1},{1,1},{2,0},{2,1},{-1,2},{0,2},{1,2}};
+            rate += get_block_bits(s, mb_x + dxy[i][0], mb_y + dxy[i][1], 1);
+        }
+    }
+    return distortion + rate*penalty_factor;
+}
+
+static int encode_subband_c0run(SnowContext *s, SubBand *b, IDWTELEM *src, IDWTELEM *parent, int stride, int orientation){
+    const int w= b->width;
+    const int h= b->height;
+    int x, y;
+
+    if(1){
+        int run=0;
+        int runs[w*h];
+        int run_index=0;
+        int max_index;
+
+        for(y=0; y<h; y++){
+            for(x=0; x<w; x++){
+                int v, p=0;
+                int /*ll=0, */l=0, lt=0, t=0, rt=0;
+                v= src[x + y*stride];
+
+                if(y){
+                    t= src[x + (y-1)*stride];
+                    if(x){
+                        lt= src[x - 1 + (y-1)*stride];
+                    }
+                    if(x + 1 < w){
+                        rt= src[x + 1 + (y-1)*stride];
+                    }
+                }
+                if(x){
+                    l= src[x - 1 + y*stride];
+                    /*if(x > 1){
+                        if(orientation==1) ll= src[y + (x-2)*stride];
+                        else               ll= src[x - 2 + y*stride];
+                    }*/
+                }
+                if(parent){
+                    int px= x>>1;
+                    int py= y>>1;
+                    if(px<b->parent->width && py<b->parent->height)
+                        p= parent[px + py*2*stride];
+                }
+                if(!(/*ll|*/l|lt|t|rt|p)){
+                    if(v){
+                        runs[run_index++]= run;
+                        run=0;
+                    }else{
+                        run++;
+                    }
+                }
+            }
+        }
+        max_index= run_index;
+        runs[run_index++]= run;
+        run_index=0;
+        run= runs[run_index++];
+
+        put_symbol2(&s->c, b->state[30], max_index, 0);
+        if(run_index <= max_index)
+            put_symbol2(&s->c, b->state[1], run, 3);
+
+        for(y=0; y<h; y++){
+            if(s->c.bytestream_end - s->c.bytestream < w*40){
+                av_log(s->avctx, AV_LOG_ERROR, "encoded frame too large\n");
+                return -1;
+            }
+            for(x=0; x<w; x++){
+                int v, p=0;
+                int /*ll=0, */l=0, lt=0, t=0, rt=0;
+                v= src[x + y*stride];
+
+                if(y){
+                    t= src[x + (y-1)*stride];
+                    if(x){
+                        lt= src[x - 1 + (y-1)*stride];
+                    }
+                    if(x + 1 < w){
+                        rt= src[x + 1 + (y-1)*stride];
+                    }
+                }
+                if(x){
+                    l= src[x - 1 + y*stride];
+                    /*if(x > 1){
+                        if(orientation==1) ll= src[y + (x-2)*stride];
+                        else               ll= src[x - 2 + y*stride];
+                    }*/
+                }
+                if(parent){
+                    int px= x>>1;
+                    int py= y>>1;
+                    if(px<b->parent->width && py<b->parent->height)
+                        p= parent[px + py*2*stride];
+                }
+                if(/*ll|*/l|lt|t|rt|p){
+                    int context= av_log2(/*FFABS(ll) + */3*FFABS(l) + FFABS(lt) + 2*FFABS(t) + FFABS(rt) + FFABS(p));
+
+                    put_rac(&s->c, &b->state[0][context], !!v);
+                }else{
+                    if(!run){
+                        run= runs[run_index++];
+
+                        if(run_index <= max_index)
+                            put_symbol2(&s->c, b->state[1], run, 3);
+                        assert(v);
+                    }else{
+                        run--;
+                        assert(!v);
+                    }
+                }
+                if(v){
+                    int context= av_log2(/*FFABS(ll) + */3*FFABS(l) + FFABS(lt) + 2*FFABS(t) + FFABS(rt) + FFABS(p));
+                    int l2= 2*FFABS(l) + (l<0);
+                    int t2= 2*FFABS(t) + (t<0);
+
+                    put_symbol2(&s->c, b->state[context + 2], FFABS(v)-1, context-4);
+                    put_rac(&s->c, &b->state[0][16 + 1 + 3 + quant3bA[l2&0xFF] + 3*quant3bA[t2&0xFF]], v<0);
+                }
+            }
+        }
+    }
+    return 0;
+}
+
+static int encode_subband(SnowContext *s, SubBand *b, IDWTELEM *src, IDWTELEM *parent, int stride, int orientation){
+//    encode_subband_qtree(s, b, src, parent, stride, orientation);
+//    encode_subband_z0run(s, b, src, parent, stride, orientation);
+    return encode_subband_c0run(s, b, src, parent, stride, orientation);
+//    encode_subband_dzr(s, b, src, parent, stride, orientation);
+}
+
+static av_always_inline int check_block(SnowContext *s, int mb_x, int mb_y, int p[3], int intra, const uint8_t *obmc_edged, int *best_rd){
+    const int b_stride= s->b_width << s->block_max_depth;
+    BlockNode *block= &s->block[mb_x + mb_y * b_stride];
+    BlockNode backup= *block;
+    int rd, index, value;
+
+    assert(mb_x>=0 && mb_y>=0);
+    assert(mb_x<b_stride);
+
+    if(intra){
+        block->color[0] = p[0];
+        block->color[1] = p[1];
+        block->color[2] = p[2];
+        block->type |= BLOCK_INTRA;
+    }else{
+        index= (p[0] + 31*p[1]) & (ME_CACHE_SIZE-1);
+        value= s->me_cache_generation + (p[0]>>10) + (p[1]<<6) + (block->ref<<12);
+        if(s->me_cache[index] == value)
+            return 0;
+        s->me_cache[index]= value;
+
+        block->mx= p[0];
+        block->my= p[1];
+        block->type &= ~BLOCK_INTRA;
+    }
+
+    rd= get_block_rd(s, mb_x, mb_y, 0, obmc_edged);
+
+//FIXME chroma
+    if(rd < *best_rd){
+        *best_rd= rd;
+        return 1;
+    }else{
+        *block= backup;
+        return 0;
+    }
+}
+
+/* special case for int[2] args we discard afterwards,
+ * fixes compilation problem with gcc 2.95 */
+static av_always_inline int check_block_inter(SnowContext *s, int mb_x, int mb_y, int p0, int p1, const uint8_t *obmc_edged, int *best_rd){
+    int p[2] = {p0, p1};
+    return check_block(s, mb_x, mb_y, p, 0, obmc_edged, best_rd);
+}
+
+static av_always_inline int check_4block_inter(SnowContext *s, int mb_x, int mb_y, int p0, int p1, int ref, int *best_rd){
+    const int b_stride= s->b_width << s->block_max_depth;
+    BlockNode *block= &s->block[mb_x + mb_y * b_stride];
+    BlockNode backup[4]= {block[0], block[1], block[b_stride], block[b_stride+1]};
+    int rd, index, value;
+
+    assert(mb_x>=0 && mb_y>=0);
+    assert(mb_x<b_stride);
+    assert(((mb_x|mb_y)&1) == 0);
+
+    index= (p0 + 31*p1) & (ME_CACHE_SIZE-1);
+    value= s->me_cache_generation + (p0>>10) + (p1<<6) + (block->ref<<12);
+    if(s->me_cache[index] == value)
+        return 0;
+    s->me_cache[index]= value;
+
+    block->mx= p0;
+    block->my= p1;
+    block->ref= ref;
+    block->type &= ~BLOCK_INTRA;
+    block[1]= block[b_stride]= block[b_stride+1]= *block;
+
+    rd= get_4block_rd(s, mb_x, mb_y, 0);
+
+//FIXME chroma
+    if(rd < *best_rd){
+        *best_rd= rd;
+        return 1;
+    }else{
+        block[0]= backup[0];
+        block[1]= backup[1];
+        block[b_stride]= backup[2];
+        block[b_stride+1]= backup[3];
+        return 0;
+    }
+}
+
+static void iterative_me(SnowContext *s){
+    int pass, mb_x, mb_y;
+    const int b_width = s->b_width  << s->block_max_depth;
+    const int b_height= s->b_height << s->block_max_depth;
+    const int b_stride= b_width;
+    int color[3];
+
+    {
+        RangeCoder r = s->c;
+        uint8_t state[sizeof(s->block_state)];
+        memcpy(state, s->block_state, sizeof(s->block_state));
+        for(mb_y= 0; mb_y<s->b_height; mb_y++)
+            for(mb_x= 0; mb_x<s->b_width; mb_x++)
+                encode_q_branch(s, 0, mb_x, mb_y);
+        s->c = r;
+        memcpy(s->block_state, state, sizeof(s->block_state));
+    }
+
+    for(pass=0; pass<25; pass++){
+        int change= 0;
+
+        for(mb_y= 0; mb_y<b_height; mb_y++){
+            for(mb_x= 0; mb_x<b_width; mb_x++){
+                int dia_change, i, j, ref;
+                int best_rd= INT_MAX, ref_rd;
+                BlockNode backup, ref_b;
+                const int index= mb_x + mb_y * b_stride;
+                BlockNode *block= &s->block[index];
+                BlockNode *tb =                   mb_y            ? &s->block[index-b_stride  ] : NULL;
+                BlockNode *lb = mb_x                              ? &s->block[index         -1] : NULL;
+                BlockNode *rb = mb_x+1<b_width                    ? &s->block[index         +1] : NULL;
+                BlockNode *bb =                   mb_y+1<b_height ? &s->block[index+b_stride  ] : NULL;
+                BlockNode *tlb= mb_x           && mb_y            ? &s->block[index-b_stride-1] : NULL;
+                BlockNode *trb= mb_x+1<b_width && mb_y            ? &s->block[index-b_stride+1] : NULL;
+                BlockNode *blb= mb_x           && mb_y+1<b_height ? &s->block[index+b_stride-1] : NULL;
+                BlockNode *brb= mb_x+1<b_width && mb_y+1<b_height ? &s->block[index+b_stride+1] : NULL;
+                const int b_w= (MB_SIZE >> s->block_max_depth);
+                uint8_t obmc_edged[b_w*2][b_w*2];
+
+                if(pass && (block->type & BLOCK_OPT))
+                    continue;
+                block->type |= BLOCK_OPT;
+
+                backup= *block;
+
+                if(!s->me_cache_generation)
+                    memset(s->me_cache, 0, sizeof(s->me_cache));
+                s->me_cache_generation += 1<<22;
+
+                //FIXME precalculate
+                {
+                    int x, y;
+                    memcpy(obmc_edged, obmc_tab[s->block_max_depth], b_w*b_w*4);
+                    if(mb_x==0)
+                        for(y=0; y<b_w*2; y++)
+                            memset(obmc_edged[y], obmc_edged[y][0] + obmc_edged[y][b_w-1], b_w);
+                    if(mb_x==b_stride-1)
+                        for(y=0; y<b_w*2; y++)
+                            memset(obmc_edged[y]+b_w, obmc_edged[y][b_w] + obmc_edged[y][b_w*2-1], b_w);
+                    if(mb_y==0){
+                        for(x=0; x<b_w*2; x++)
+                            obmc_edged[0][x] += obmc_edged[b_w-1][x];
+                        for(y=1; y<b_w; y++)
+                            memcpy(obmc_edged[y], obmc_edged[0], b_w*2);
+                    }
+                    if(mb_y==b_height-1){
+                        for(x=0; x<b_w*2; x++)
+                            obmc_edged[b_w*2-1][x] += obmc_edged[b_w][x];
+                        for(y=b_w; y<b_w*2-1; y++)
+                            memcpy(obmc_edged[y], obmc_edged[b_w*2-1], b_w*2);
+                    }
+                }
+
+                //skip stuff outside the picture
+                if(mb_x==0 || mb_y==0 || mb_x==b_width-1 || mb_y==b_height-1){
+                    uint8_t *src= s->  input_picture.data[0];
+                    uint8_t *dst= s->current_picture.data[0];
+                    const int stride= s->current_picture.linesize[0];
+                    const int block_w= MB_SIZE >> s->block_max_depth;
+                    const int sx= block_w*mb_x - block_w/2;
+                    const int sy= block_w*mb_y - block_w/2;
+                    const int w= s->plane[0].width;
+                    const int h= s->plane[0].height;
+                    int y;
+
+                    for(y=sy; y<0; y++)
+                        memcpy(dst + sx + y*stride, src + sx + y*stride, block_w*2);
+                    for(y=h; y<sy+block_w*2; y++)
+                        memcpy(dst + sx + y*stride, src + sx + y*stride, block_w*2);
+                    if(sx<0){
+                        for(y=sy; y<sy+block_w*2; y++)
+                            memcpy(dst + sx + y*stride, src + sx + y*stride, -sx);
+                    }
+                    if(sx+block_w*2 > w){
+                        for(y=sy; y<sy+block_w*2; y++)
+                            memcpy(dst + w + y*stride, src + w + y*stride, sx+block_w*2 - w);
+                    }
+                }
+
+                // intra(black) = neighbors' contribution to the current block
+                for(i=0; i<3; i++)
+                    color[i]= get_dc(s, mb_x, mb_y, i);
+
+                // get previous score (cannot be cached due to OBMC)
+                if(pass > 0 && (block->type&BLOCK_INTRA)){
+                    int color0[3]= {block->color[0], block->color[1], block->color[2]};
+                    check_block(s, mb_x, mb_y, color0, 1, *obmc_edged, &best_rd);
+                }else
+                    check_block_inter(s, mb_x, mb_y, block->mx, block->my, *obmc_edged, &best_rd);
+
+                ref_b= *block;
+                ref_rd= best_rd;
+                for(ref=0; ref < s->ref_frames; ref++){
+                    int16_t (*mvr)[2]= &s->ref_mvs[ref][index];
+                    if(s->ref_scores[ref][index] > s->ref_scores[ref_b.ref][index]*3/2) //FIXME tune threshold
+                        continue;
+                    block->ref= ref;
+                    best_rd= INT_MAX;
+
+                    check_block_inter(s, mb_x, mb_y, mvr[0][0], mvr[0][1], *obmc_edged, &best_rd);
+                    check_block_inter(s, mb_x, mb_y, 0, 0, *obmc_edged, &best_rd);
+                    if(tb)
+                        check_block_inter(s, mb_x, mb_y, mvr[-b_stride][0], mvr[-b_stride][1], *obmc_edged, &best_rd);
+                    if(lb)
+                        check_block_inter(s, mb_x, mb_y, mvr[-1][0], mvr[-1][1], *obmc_edged, &best_rd);
+                    if(rb)
+                        check_block_inter(s, mb_x, mb_y, mvr[1][0], mvr[1][1], *obmc_edged, &best_rd);
+                    if(bb)
+                        check_block_inter(s, mb_x, mb_y, mvr[b_stride][0], mvr[b_stride][1], *obmc_edged, &best_rd);
+
+                    /* fullpel ME */
+                    //FIXME avoid subpel interpolation / round to nearest integer
+                    do{
+                        dia_change=0;
+                        for(i=0; i<FFMAX(s->avctx->dia_size, 1); i++){
+                            for(j=0; j<i; j++){
+                                dia_change |= check_block_inter(s, mb_x, mb_y, block->mx+4*(i-j), block->my+(4*j), *obmc_edged, &best_rd);
+                                dia_change |= check_block_inter(s, mb_x, mb_y, block->mx-4*(i-j), block->my-(4*j), *obmc_edged, &best_rd);
+                                dia_change |= check_block_inter(s, mb_x, mb_y, block->mx+4*(i-j), block->my-(4*j), *obmc_edged, &best_rd);
+                                dia_change |= check_block_inter(s, mb_x, mb_y, block->mx-4*(i-j), block->my+(4*j), *obmc_edged, &best_rd);
+                            }
+                        }
+                    }while(dia_change);
+                    /* subpel ME */
+                    do{
+                        static const int square[8][2]= {{+1, 0},{-1, 0},{ 0,+1},{ 0,-1},{+1,+1},{-1,-1},{+1,-1},{-1,+1},};
+                        dia_change=0;
+                        for(i=0; i<8; i++)
+                            dia_change |= check_block_inter(s, mb_x, mb_y, block->mx+square[i][0], block->my+square[i][1], *obmc_edged, &best_rd);
+                    }while(dia_change);
+                    //FIXME or try the standard 2 pass qpel or similar
+
+                    mvr[0][0]= block->mx;
+                    mvr[0][1]= block->my;
+                    if(ref_rd > best_rd){
+                        ref_rd= best_rd;
+                        ref_b= *block;
+                    }
+                }
+                best_rd= ref_rd;
+                *block= ref_b;
+                check_block(s, mb_x, mb_y, color, 1, *obmc_edged, &best_rd);
+                //FIXME RD style color selection
+                if(!same_block(block, &backup)){
+                    if(tb ) tb ->type &= ~BLOCK_OPT;
+                    if(lb ) lb ->type &= ~BLOCK_OPT;
+                    if(rb ) rb ->type &= ~BLOCK_OPT;
+                    if(bb ) bb ->type &= ~BLOCK_OPT;
+                    if(tlb) tlb->type &= ~BLOCK_OPT;
+                    if(trb) trb->type &= ~BLOCK_OPT;
+                    if(blb) blb->type &= ~BLOCK_OPT;
+                    if(brb) brb->type &= ~BLOCK_OPT;
+                    change ++;
+                }
+            }
+        }
+        av_log(s->avctx, AV_LOG_ERROR, "pass:%d changed:%d\n", pass, change);
+        if(!change)
+            break;
+    }
+
+    if(s->block_max_depth == 1){
+        int change= 0;
+        for(mb_y= 0; mb_y<b_height; mb_y+=2){
+            for(mb_x= 0; mb_x<b_width; mb_x+=2){
+                int i;
+                int best_rd, init_rd;
+                const int index= mb_x + mb_y * b_stride;
+                BlockNode *b[4];
+
+                b[0]= &s->block[index];
+                b[1]= b[0]+1;
+                b[2]= b[0]+b_stride;
+                b[3]= b[2]+1;
+                if(same_block(b[0], b[1]) &&
+                   same_block(b[0], b[2]) &&
+                   same_block(b[0], b[3]))
+                    continue;
+
+                if(!s->me_cache_generation)
+                    memset(s->me_cache, 0, sizeof(s->me_cache));
+                s->me_cache_generation += 1<<22;
+
+                init_rd= best_rd= get_4block_rd(s, mb_x, mb_y, 0);
+
+                //FIXME more multiref search?
+                check_4block_inter(s, mb_x, mb_y,
+                                   (b[0]->mx + b[1]->mx + b[2]->mx + b[3]->mx + 2) >> 2,
+                                   (b[0]->my + b[1]->my + b[2]->my + b[3]->my + 2) >> 2, 0, &best_rd);
+
+                for(i=0; i<4; i++)
+                    if(!(b[i]->type&BLOCK_INTRA))
+                        check_4block_inter(s, mb_x, mb_y, b[i]->mx, b[i]->my, b[i]->ref, &best_rd);
+
+                if(init_rd != best_rd)
+                    change++;
+            }
+        }
+        av_log(s->avctx, AV_LOG_ERROR, "pass:4mv changed:%d\n", change*4);
+    }
+}
+
+static void encode_blocks(SnowContext *s, int search){
+    int x, y;
+    int w= s->b_width;
+    int h= s->b_height;
+
+    if(s->avctx->me_method == ME_ITER && !s->keyframe && search)
+        iterative_me(s);
+
+    for(y=0; y<h; y++){
+        if(s->c.bytestream_end - s->c.bytestream < w*MB_SIZE*MB_SIZE*3){ //FIXME nicer limit
+            av_log(s->avctx, AV_LOG_ERROR, "encoded frame too large\n");
+            return;
+        }
+        for(x=0; x<w; x++){
+            if(s->avctx->me_method == ME_ITER || !search)
+                encode_q_branch2(s, 0, x, y);
+            else
+                encode_q_branch (s, 0, x, y);
+        }
+    }
+}
+
+static void quantize(SnowContext *s, SubBand *b, IDWTELEM *dst, DWTELEM *src, int stride, int bias){
+    const int w= b->width;
+    const int h= b->height;
+    const int qlog= av_clip(s->qlog + b->qlog, 0, QROOT*16);
+    const int qmul= qexp[qlog&(QROOT-1)]<<((qlog>>QSHIFT) + ENCODER_EXTRA_BITS);
+    int x,y, thres1, thres2;
+
+    if(s->qlog == LOSSLESS_QLOG){
+        for(y=0; y<h; y++)
+            for(x=0; x<w; x++)
+                dst[x + y*stride]= src[x + y*stride];
+        return;
+    }
+
+    bias= bias ? 0 : (3*qmul)>>3;
+    thres1= ((qmul - bias)>>QEXPSHIFT) - 1;
+    thres2= 2*thres1;
+
+    if(!bias){
+        for(y=0; y<h; y++){
+            for(x=0; x<w; x++){
+                int i= src[x + y*stride];
+
+                if((unsigned)(i+thres1) > thres2){
+                    if(i>=0){
+                        i<<= QEXPSHIFT;
+                        i/= qmul; //FIXME optimize
+                        dst[x + y*stride]=  i;
+                    }else{
+                        i= -i;
+                        i<<= QEXPSHIFT;
+                        i/= qmul; //FIXME optimize
+                        dst[x + y*stride]= -i;
+                    }
+                }else
+                    dst[x + y*stride]= 0;
+            }
+        }
+    }else{
+        for(y=0; y<h; y++){
+            for(x=0; x<w; x++){
+                int i= src[x + y*stride];
+
+                if((unsigned)(i+thres1) > thres2){
+                    if(i>=0){
+                        i<<= QEXPSHIFT;
+                        i= (i + bias) / qmul; //FIXME optimize
+                        dst[x + y*stride]=  i;
+                    }else{
+                        i= -i;
+                        i<<= QEXPSHIFT;
+                        i= (i + bias) / qmul; //FIXME optimize
+                        dst[x + y*stride]= -i;
+                    }
+                }else
+                    dst[x + y*stride]= 0;
+            }
+        }
+    }
+}
+
+static void dequantize(SnowContext *s, SubBand *b, IDWTELEM *src, int stride){
+    const int w= b->width;
+    const int h= b->height;
+    const int qlog= av_clip(s->qlog + b->qlog, 0, QROOT*16);
+    const int qmul= qexp[qlog&(QROOT-1)]<<(qlog>>QSHIFT);
+    const int qadd= (s->qbias*qmul)>>QBIAS_SHIFT;
+    int x,y;
+
+    if(s->qlog == LOSSLESS_QLOG) return;
+
+    for(y=0; y<h; y++){
+        for(x=0; x<w; x++){
+            int i= src[x + y*stride];
+            if(i<0){
+                src[x + y*stride]= -((-i*qmul + qadd)>>(QEXPSHIFT)); //FIXME try different bias
+            }else if(i>0){
+                src[x + y*stride]=  (( i*qmul + qadd)>>(QEXPSHIFT));
+            }
+        }
+    }
+}
+
+static void decorrelate(SnowContext *s, SubBand *b, IDWTELEM *src, int stride, int inverse, int use_median){
+    const int w= b->width;
+    const int h= b->height;
+    int x,y;
+
+    for(y=h-1; y>=0; y--){
+        for(x=w-1; x>=0; x--){
+            int i= x + y*stride;
+
+            if(x){
+                if(use_median){
+                    if(y && x+1<w) src[i] -= mid_pred(src[i - 1], src[i - stride], src[i - stride + 1]);
+                    else  src[i] -= src[i - 1];
+                }else{
+                    if(y) src[i] -= mid_pred(src[i - 1], src[i - stride], src[i - 1] + src[i - stride] - src[i - 1 - stride]);
+                    else  src[i] -= src[i - 1];
+                }
+            }else{
+                if(y) src[i] -= src[i - stride];
+            }
+        }
+    }
+}
+
+static void correlate(SnowContext *s, SubBand *b, IDWTELEM *src, int stride, int inverse, int use_median){
+    const int w= b->width;
+    const int h= b->height;
+    int x,y;
+
+    for(y=0; y<h; y++){
+        for(x=0; x<w; x++){
+            int i= x + y*stride;
+
+            if(x){
+                if(use_median){
+                    if(y && x+1<w) src[i] += mid_pred(src[i - 1], src[i - stride], src[i - stride + 1]);
+                    else  src[i] += src[i - 1];
+                }else{
+                    if(y) src[i] += mid_pred(src[i - 1], src[i - stride], src[i - 1] + src[i - stride] - src[i - 1 - stride]);
+                    else  src[i] += src[i - 1];
+                }
+            }else{
+                if(y) src[i] += src[i - stride];
+            }
+        }
+    }
+}
+
+static void encode_qlogs(SnowContext *s){
+    int plane_index, level, orientation;
+
+    for(plane_index=0; plane_index<2; plane_index++){
+        for(level=0; level<s->spatial_decomposition_count; level++){
+            for(orientation=level ? 1:0; orientation<4; orientation++){
+                if(orientation==2) continue;
+                put_symbol(&s->c, s->header_state, s->plane[plane_index].band[level][orientation].qlog, 1);
+            }
+        }
+    }
+}
+
+static void encode_header(SnowContext *s){
+    int plane_index, i;
+    uint8_t kstate[32];
+
+    memset(kstate, MID_STATE, sizeof(kstate));
+
+    put_rac(&s->c, kstate, s->keyframe);
+    if(s->keyframe || s->always_reset){
+        ff_snow_reset_contexts(s);
+        s->last_spatial_decomposition_type=
+        s->last_qlog=
+        s->last_qbias=
+        s->last_mv_scale=
+        s->last_block_max_depth= 0;
+        for(plane_index=0; plane_index<2; plane_index++){
+            Plane *p= &s->plane[plane_index];
+            p->last_htaps=0;
+            p->last_diag_mc=0;
+            memset(p->last_hcoeff, 0, sizeof(p->last_hcoeff));
+        }
+    }
+    if(s->keyframe){
+        put_symbol(&s->c, s->header_state, s->version, 0);
+        put_rac(&s->c, s->header_state, s->always_reset);
+        put_symbol(&s->c, s->header_state, s->temporal_decomposition_type, 0);
+        put_symbol(&s->c, s->header_state, s->temporal_decomposition_count, 0);
+        put_symbol(&s->c, s->header_state, s->spatial_decomposition_count, 0);
+        put_symbol(&s->c, s->header_state, s->colorspace_type, 0);
+        put_symbol(&s->c, s->header_state, s->chroma_h_shift, 0);
+        put_symbol(&s->c, s->header_state, s->chroma_v_shift, 0);
+        put_rac(&s->c, s->header_state, s->spatial_scalability);
+//        put_rac(&s->c, s->header_state, s->rate_scalability);
+        put_symbol(&s->c, s->header_state, s->max_ref_frames-1, 0);
+
+        encode_qlogs(s);
+    }
+
+    if(!s->keyframe){
+        int update_mc=0;
+        for(plane_index=0; plane_index<2; plane_index++){
+            Plane *p= &s->plane[plane_index];
+            update_mc |= p->last_htaps   != p->htaps;
+            update_mc |= p->last_diag_mc != p->diag_mc;
+            update_mc |= !!memcmp(p->last_hcoeff, p->hcoeff, sizeof(p->hcoeff));
+        }
+        put_rac(&s->c, s->header_state, update_mc);
+        if(update_mc){
+            for(plane_index=0; plane_index<2; plane_index++){
+                Plane *p= &s->plane[plane_index];
+                put_rac(&s->c, s->header_state, p->diag_mc);
+                put_symbol(&s->c, s->header_state, p->htaps/2-1, 0);
+                for(i= p->htaps/2; i; i--)
+                    put_symbol(&s->c, s->header_state, FFABS(p->hcoeff[i]), 0);
+            }
+        }
+        if(s->last_spatial_decomposition_count != s->spatial_decomposition_count){
+            put_rac(&s->c, s->header_state, 1);
+            put_symbol(&s->c, s->header_state, s->spatial_decomposition_count, 0);
+            encode_qlogs(s);
+        }else
+            put_rac(&s->c, s->header_state, 0);
+    }
+
+    put_symbol(&s->c, s->header_state, s->spatial_decomposition_type - s->last_spatial_decomposition_type, 1);
+    put_symbol(&s->c, s->header_state, s->qlog            - s->last_qlog    , 1);
+    put_symbol(&s->c, s->header_state, s->mv_scale        - s->last_mv_scale, 1);
+    put_symbol(&s->c, s->header_state, s->qbias           - s->last_qbias   , 1);
+    put_symbol(&s->c, s->header_state, s->block_max_depth - s->last_block_max_depth, 1);
+
+}
+
+static void update_last_header_values(SnowContext *s){
+    int plane_index;
+
+    if(!s->keyframe){
+        for(plane_index=0; plane_index<2; plane_index++){
+            Plane *p= &s->plane[plane_index];
+            p->last_diag_mc= p->diag_mc;
+            p->last_htaps  = p->htaps;
+            memcpy(p->last_hcoeff, p->hcoeff, sizeof(p->hcoeff));
+        }
+    }
+
+    s->last_spatial_decomposition_type  = s->spatial_decomposition_type;
+    s->last_qlog                        = s->qlog;
+    s->last_qbias                       = s->qbias;
+    s->last_mv_scale                    = s->mv_scale;
+    s->last_block_max_depth             = s->block_max_depth;
+    s->last_spatial_decomposition_count = s->spatial_decomposition_count;
+}
+
+static int qscale2qlog(int qscale){
+    return rint(QROOT*log(qscale / (float)FF_QP2LAMBDA)/log(2))
+           + 61*QROOT/8; ///< 64 > 60
+}
+
+static int ratecontrol_1pass(SnowContext *s, AVFrame *pict)
+{
+    /* Estimate the frame's complexity as a sum of weighted dwt coefficients.
+     * FIXME we know exact mv bits at this point,
+     * but ratecontrol isn't set up to include them. */
+    uint32_t coef_sum= 0;
+    int level, orientation, delta_qlog;
+
+    for(level=0; level<s->spatial_decomposition_count; level++){
+        for(orientation=level ? 1 : 0; orientation<4; orientation++){
+            SubBand *b= &s->plane[0].band[level][orientation];
+            IDWTELEM *buf= b->ibuf;
+            const int w= b->width;
+            const int h= b->height;
+            const int stride= b->stride;
+            const int qlog= av_clip(2*QROOT + b->qlog, 0, QROOT*16);
+            const int qmul= qexp[qlog&(QROOT-1)]<<(qlog>>QSHIFT);
+            const int qdiv= (1<<16)/qmul;
+            int x, y;
+            //FIXME this is ugly
+            for(y=0; y<h; y++)
+                for(x=0; x<w; x++)
+                    buf[x+y*stride]= b->buf[x+y*stride];
+            if(orientation==0)
+                decorrelate(s, b, buf, stride, 1, 0);
+            for(y=0; y<h; y++)
+                for(x=0; x<w; x++)
+                    coef_sum+= abs(buf[x+y*stride]) * qdiv >> 16;
+        }
+    }
+
+    /* ugly, ratecontrol just takes a sqrt again */
+    coef_sum = (uint64_t)coef_sum * coef_sum >> 16;
+    assert(coef_sum < INT_MAX);
+
+    if(pict->pict_type == AV_PICTURE_TYPE_I){
+        s->m.current_picture.mb_var_sum= coef_sum;
+        s->m.current_picture.mc_mb_var_sum= 0;
+    }else{
+        s->m.current_picture.mc_mb_var_sum= coef_sum;
+        s->m.current_picture.mb_var_sum= 0;
+    }
+
+    pict->quality= ff_rate_estimate_qscale(&s->m, 1);
+    if (pict->quality < 0)
+        return INT_MIN;
+    s->lambda= pict->quality * 3/2;
+    delta_qlog= qscale2qlog(pict->quality) - s->qlog;
+    s->qlog+= delta_qlog;
+    return delta_qlog;
+}
+
+static void calculate_visual_weight(SnowContext *s, Plane *p){
+    int width = p->width;
+    int height= p->height;
+    int level, orientation, x, y;
+
+    for(level=0; level<s->spatial_decomposition_count; level++){
+        for(orientation=level ? 1 : 0; orientation<4; orientation++){
+            SubBand *b= &p->band[level][orientation];
+            IDWTELEM *ibuf= b->ibuf;
+            int64_t error=0;
+
+            memset(s->spatial_idwt_buffer, 0, sizeof(*s->spatial_idwt_buffer)*width*height);
+            ibuf[b->width/2 + b->height/2*b->stride]= 256*16;
+            ff_spatial_idwt(s->spatial_idwt_buffer, width, height, width, s->spatial_decomposition_type, s->spatial_decomposition_count);
+            for(y=0; y<height; y++){
+                for(x=0; x<width; x++){
+                    int64_t d= s->spatial_idwt_buffer[x + y*width]*16;
+                    error += d*d;
+                }
+            }
+
+            b->qlog= (int)(log(352256.0/sqrt(error)) / log(pow(2.0, 1.0/QROOT))+0.5);
+        }
+    }
+}
+
+static int encode_frame(AVCodecContext *avctx, unsigned char *buf, int buf_size, void *data){
+    SnowContext *s = avctx->priv_data;
+    RangeCoder * const c= &s->c;
+    AVFrame *pict = data;
+    const int width= s->avctx->width;
+    const int height= s->avctx->height;
+    int level, orientation, plane_index, i, y;
+    uint8_t rc_header_bak[sizeof(s->header_state)];
+    uint8_t rc_block_bak[sizeof(s->block_state)];
+
+    ff_init_range_encoder(c, buf, buf_size);
+    ff_build_rac_states(c, 0.05*(1LL<<32), 256-8);
+
+    for(i=0; i<3; i++){
+        int shift= !!i;
+        for(y=0; y<(height>>shift); y++)
+            memcpy(&s->input_picture.data[i][y * s->input_picture.linesize[i]],
+                   &pict->data[i][y * pict->linesize[i]],
+                   width>>shift);
+    }
+    s->new_picture = *pict;
+
+    s->m.picture_number= avctx->frame_number;
+    if(avctx->flags&CODEC_FLAG_PASS2){
+        s->m.pict_type =
+        pict->pict_type= s->m.rc_context.entry[avctx->frame_number].new_pict_type;
+        s->keyframe= pict->pict_type==AV_PICTURE_TYPE_I;
+        if(!(avctx->flags&CODEC_FLAG_QSCALE)) {
+            pict->quality= ff_rate_estimate_qscale(&s->m, 0);
+            if (pict->quality < 0)
+                return -1;
+        }
+    }else{
+        s->keyframe= avctx->gop_size==0 || avctx->frame_number % avctx->gop_size == 0;
+        s->m.pict_type=
+        pict->pict_type= s->keyframe ? AV_PICTURE_TYPE_I : AV_PICTURE_TYPE_P;
+    }
+
+    if(s->pass1_rc && avctx->frame_number == 0)
+        pict->quality= 2*FF_QP2LAMBDA;
+    if(pict->quality){
+        s->qlog= qscale2qlog(pict->quality);
+        s->lambda = pict->quality * 3/2;
+    }
+    if(s->qlog < 0 || (!pict->quality && (avctx->flags & CODEC_FLAG_QSCALE))){
+        s->qlog= LOSSLESS_QLOG;
+        s->lambda = 0;
+    }//else keep previous frame's qlog until after motion estimation
+
+    ff_snow_frame_start(s);
+
+    s->m.current_picture_ptr= &s->m.current_picture;
+    s->m.last_picture.f.pts = s->m.current_picture.f.pts;
+    s->m.current_picture.f.pts = pict->pts;
+    if(pict->pict_type == AV_PICTURE_TYPE_P){
+        int block_width = (width +15)>>4;
+        int block_height= (height+15)>>4;
+        int stride= s->current_picture.linesize[0];
+
+        assert(s->current_picture.data[0]);
+        assert(s->last_picture[0].data[0]);
+
+        s->m.avctx= s->avctx;
+        s->m.current_picture.f.data[0] = s->current_picture.data[0];
+        s->m.   last_picture.f.data[0] = s->last_picture[0].data[0];
+        s->m.    new_picture.f.data[0] = s->  input_picture.data[0];
+        s->m.   last_picture_ptr= &s->m.   last_picture;
+        s->m.linesize=
+        s->m.   last_picture.f.linesize[0] =
+        s->m.    new_picture.f.linesize[0] =
+        s->m.current_picture.f.linesize[0] = stride;
+        s->m.uvlinesize= s->current_picture.linesize[1];
+        s->m.width = width;
+        s->m.height= height;
+        s->m.mb_width = block_width;
+        s->m.mb_height= block_height;
+        s->m.mb_stride=   s->m.mb_width+1;
+        s->m.b8_stride= 2*s->m.mb_width+1;
+        s->m.f_code=1;
+        s->m.pict_type= pict->pict_type;
+        s->m.me_method= s->avctx->me_method;
+        s->m.me.scene_change_score=0;
+        s->m.flags= s->avctx->flags;
+        s->m.quarter_sample= (s->avctx->flags & CODEC_FLAG_QPEL)!=0;
+        s->m.out_format= FMT_H263;
+        s->m.unrestricted_mv= 1;
+
+        s->m.lambda = s->lambda;
+        s->m.qscale= (s->m.lambda*139 + FF_LAMBDA_SCALE*64) >> (FF_LAMBDA_SHIFT + 7);
+        s->lambda2= s->m.lambda2= (s->m.lambda*s->m.lambda + FF_LAMBDA_SCALE/2) >> FF_LAMBDA_SHIFT;
+
+        s->m.dsp= s->dsp; //move
+        ff_init_me(&s->m);
+        s->dsp= s->m.dsp;
+    }
+
+    if(s->pass1_rc){
+        memcpy(rc_header_bak, s->header_state, sizeof(s->header_state));
+        memcpy(rc_block_bak, s->block_state, sizeof(s->block_state));
+    }
+
+redo_frame:
+
+    if(pict->pict_type == AV_PICTURE_TYPE_I)
+        s->spatial_decomposition_count= 5;
+    else
+        s->spatial_decomposition_count= 5;
+
+    s->m.pict_type = pict->pict_type;
+    s->qbias= pict->pict_type == AV_PICTURE_TYPE_P ? 2 : 0;
+
+    ff_snow_common_init_after_header(avctx);
+
+    if(s->last_spatial_decomposition_count != s->spatial_decomposition_count){
+        for(plane_index=0; plane_index<3; plane_index++){
+            calculate_visual_weight(s, &s->plane[plane_index]);
+        }
+    }
+
+    encode_header(s);
+    s->m.misc_bits = 8*(s->c.bytestream - s->c.bytestream_start);
+    encode_blocks(s, 1);
+    s->m.mv_bits = 8*(s->c.bytestream - s->c.bytestream_start) - s->m.misc_bits;
+
+    for(plane_index=0; plane_index<3; plane_index++){
+        Plane *p= &s->plane[plane_index];
+        int w= p->width;
+        int h= p->height;
+        int x, y;
+//        int bits= put_bits_count(&s->c.pb);
+
+        if (!s->memc_only) {
+            //FIXME optimize
+            if(pict->data[plane_index]) //FIXME gray hack
+                for(y=0; y<h; y++){
+                    for(x=0; x<w; x++){
+                        s->spatial_idwt_buffer[y*w + x]= pict->data[plane_index][y*pict->linesize[plane_index] + x]<<FRAC_BITS;
+                    }
+                }
+            predict_plane(s, s->spatial_idwt_buffer, plane_index, 0);
+
+            if(   plane_index==0
+               && pict->pict_type == AV_PICTURE_TYPE_P
+               && !(avctx->flags&CODEC_FLAG_PASS2)
+               && s->m.me.scene_change_score > s->avctx->scenechange_threshold){
+                ff_init_range_encoder(c, buf, buf_size);
+                ff_build_rac_states(c, 0.05*(1LL<<32), 256-8);
+                pict->pict_type= AV_PICTURE_TYPE_I;
+                s->keyframe=1;
+                s->current_picture.key_frame=1;
+                goto redo_frame;
+            }
+
+            if(s->qlog == LOSSLESS_QLOG){
+                for(y=0; y<h; y++){
+                    for(x=0; x<w; x++){
+                        s->spatial_dwt_buffer[y*w + x]= (s->spatial_idwt_buffer[y*w + x] + (1<<(FRAC_BITS-1))-1)>>FRAC_BITS;
+                    }
+                }
+            }else{
+                for(y=0; y<h; y++){
+                    for(x=0; x<w; x++){
+                        s->spatial_dwt_buffer[y*w + x]=s->spatial_idwt_buffer[y*w + x]<<ENCODER_EXTRA_BITS;
+                    }
+                }
+            }
+
+            /*  if(QUANTIZE2)
+                dwt_quantize(s, p, s->spatial_dwt_buffer, w, h, w, s->spatial_decomposition_type);
+            else*/
+                ff_spatial_dwt(s->spatial_dwt_buffer, w, h, w, s->spatial_decomposition_type, s->spatial_decomposition_count);
+
+            if(s->pass1_rc && plane_index==0){
+                int delta_qlog = ratecontrol_1pass(s, pict);
+                if (delta_qlog <= INT_MIN)
+                    return -1;
+                if(delta_qlog){
+                    //reordering qlog in the bitstream would eliminate this reset
+                    ff_init_range_encoder(c, buf, buf_size);
+                    memcpy(s->header_state, rc_header_bak, sizeof(s->header_state));
+                    memcpy(s->block_state, rc_block_bak, sizeof(s->block_state));
+                    encode_header(s);
+                    encode_blocks(s, 0);
+                }
+            }
+
+            for(level=0; level<s->spatial_decomposition_count; level++){
+                for(orientation=level ? 1 : 0; orientation<4; orientation++){
+                    SubBand *b= &p->band[level][orientation];
+
+                    if(!QUANTIZE2)
+                        quantize(s, b, b->ibuf, b->buf, b->stride, s->qbias);
+                    if(orientation==0)
+                        decorrelate(s, b, b->ibuf, b->stride, pict->pict_type == AV_PICTURE_TYPE_P, 0);
+                    encode_subband(s, b, b->ibuf, b->parent ? b->parent->ibuf : NULL, b->stride, orientation);
+                    assert(b->parent==NULL || b->parent->stride == b->stride*2);
+                    if(orientation==0)
+                        correlate(s, b, b->ibuf, b->stride, 1, 0);
+                }
+            }
+
+            for(level=0; level<s->spatial_decomposition_count; level++){
+                for(orientation=level ? 1 : 0; orientation<4; orientation++){
+                    SubBand *b= &p->band[level][orientation];
+
+                    dequantize(s, b, b->ibuf, b->stride);
+                }
+            }
+
+            ff_spatial_idwt(s->spatial_idwt_buffer, w, h, w, s->spatial_decomposition_type, s->spatial_decomposition_count);
+            if(s->qlog == LOSSLESS_QLOG){
+                for(y=0; y<h; y++){
+                    for(x=0; x<w; x++){
+                        s->spatial_idwt_buffer[y*w + x]<<=FRAC_BITS;
+                    }
+                }
+            }
+            predict_plane(s, s->spatial_idwt_buffer, plane_index, 1);
+        }else{
+            //ME/MC only
+            if(pict->pict_type == AV_PICTURE_TYPE_I){
+                for(y=0; y<h; y++){
+                    for(x=0; x<w; x++){
+                        s->current_picture.data[plane_index][y*s->current_picture.linesize[plane_index] + x]=
+                            pict->data[plane_index][y*pict->linesize[plane_index] + x];
+                    }
+                }
+            }else{
+                memset(s->spatial_idwt_buffer, 0, sizeof(IDWTELEM)*w*h);
+                predict_plane(s, s->spatial_idwt_buffer, plane_index, 1);
+            }
+        }
+        if(s->avctx->flags&CODEC_FLAG_PSNR){
+            int64_t error= 0;
+
+            if(pict->data[plane_index]) //FIXME gray hack
+                for(y=0; y<h; y++){
+                    for(x=0; x<w; x++){
+                        int d= s->current_picture.data[plane_index][y*s->current_picture.linesize[plane_index] + x] - pict->data[plane_index][y*pict->linesize[plane_index] + x];
+                        error += d*d;
+                    }
+                }
+            s->avctx->error[plane_index] += error;
+            s->current_picture.error[plane_index] = error;
+        }
+
+    }
+
+    update_last_header_values(s);
+
+    ff_snow_release_buffer(avctx);
+
+    s->current_picture.coded_picture_number = avctx->frame_number;
+    s->current_picture.pict_type = pict->pict_type;
+    s->current_picture.quality = pict->quality;
+    s->m.frame_bits = 8*(s->c.bytestream - s->c.bytestream_start);
+    s->m.p_tex_bits = s->m.frame_bits - s->m.misc_bits - s->m.mv_bits;
+    s->m.current_picture.f.display_picture_number =
+    s->m.current_picture.f.coded_picture_number   = avctx->frame_number;
+    s->m.current_picture.f.quality                = pict->quality;
+    s->m.total_bits += 8*(s->c.bytestream - s->c.bytestream_start);
+    if(s->pass1_rc)
+        if (ff_rate_estimate_qscale(&s->m, 0) < 0)
+            return -1;
+    if(avctx->flags&CODEC_FLAG_PASS1)
+        ff_write_pass1_stats(&s->m);
+    s->m.last_pict_type = s->m.pict_type;
+    avctx->frame_bits = s->m.frame_bits;
+    avctx->mv_bits = s->m.mv_bits;
+    avctx->misc_bits = s->m.misc_bits;
+    avctx->p_tex_bits = s->m.p_tex_bits;
+
+    emms_c();
+
+    return ff_rac_terminate(c);
+}
+
+static av_cold int encode_end(AVCodecContext *avctx)
+{
+    SnowContext *s = avctx->priv_data;
+
+    ff_snow_common_end(s);
+    if (s->input_picture.data[0])
+        avctx->release_buffer(avctx, &s->input_picture);
+    av_free(avctx->stats_out);
+
+    return 0;
+}
+
+#define OFFSET(x) offsetof(SnowContext, x)
+#define VE AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_ENCODING_PARAM
+static const AVOption options[] = {
+    { "memc_only",      "Only do ME/MC (I frames -> ref, P frame -> ME+MC).",   OFFSET(memc_only), AV_OPT_TYPE_INT, { 0 }, 0, 1, VE },
+    { NULL },
+};
+
+static const AVClass snowenc_class = {
+    .class_name = "snow encoder",
+    .item_name  = av_default_item_name,
+    .option     = options,
+    .version    = LIBAVUTIL_VERSION_INT,
+};
+
+AVCodec ff_snow_encoder = {
+    .name           = "snow",
+    .type           = AVMEDIA_TYPE_VIDEO,
+    .id             = CODEC_ID_SNOW,
+    .priv_data_size = sizeof(SnowContext),
+    .init           = encode_init,
+    .encode         = encode_frame,
+    .close          = encode_end,
+    .long_name = NULL_IF_CONFIG_SMALL("Snow"),
+    .priv_class     = &snowenc_class,
+};
+#endif



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