[FFmpeg-cvslog] r14790 - in trunk/libavcodec: Makefile flacenc.c lpc.c lpc.h

ramiro subversion
Sat Aug 16 19:18:21 CEST 2008


Author: ramiro
Date: Sat Aug 16 19:18:20 2008
New Revision: 14790

Log:
flacenc, lpc: Move LPC code from flacenc.c to new lpc.[ch] files.

Added:
   trunk/libavcodec/lpc.c
      - copied, changed from r14789, /trunk/libavcodec/flacenc.c
   trunk/libavcodec/lpc.h
      - copied, changed from r14789, /trunk/libavcodec/flacenc.c
Modified:
   trunk/libavcodec/Makefile
   trunk/libavcodec/flacenc.c

Modified: trunk/libavcodec/Makefile
==============================================================================
--- trunk/libavcodec/Makefile	(original)
+++ trunk/libavcodec/Makefile	Sat Aug 16 19:18:20 2008
@@ -72,7 +72,7 @@ OBJS-$(CONFIG_FFV1_ENCODER)            +
 OBJS-$(CONFIG_FFVHUFF_DECODER)         += huffyuv.o
 OBJS-$(CONFIG_FFVHUFF_ENCODER)         += huffyuv.o
 OBJS-$(CONFIG_FLAC_DECODER)            += flac.o golomb.o
-OBJS-$(CONFIG_FLAC_ENCODER)            += flacenc.o golomb.o
+OBJS-$(CONFIG_FLAC_ENCODER)            += flacenc.o golomb.o lpc.o
 OBJS-$(CONFIG_FLASHSV_DECODER)         += flashsv.o
 OBJS-$(CONFIG_FLASHSV_ENCODER)         += flashsvenc.o
 OBJS-$(CONFIG_FLIC_DECODER)            += flicvideo.o

Modified: trunk/libavcodec/flacenc.c
==============================================================================
--- trunk/libavcodec/flacenc.c	(original)
+++ trunk/libavcodec/flacenc.c	Sat Aug 16 19:18:20 2008
@@ -25,6 +25,7 @@
 #include "bitstream.h"
 #include "dsputil.h"
 #include "golomb.h"
+#include "lpc.h"
 
 #define FLAC_MAX_CH  8
 #define FLAC_MIN_BLOCKSIZE  16
@@ -41,17 +42,8 @@
 #define FLAC_CHMODE_RIGHT_SIDE      9
 #define FLAC_CHMODE_MID_SIDE       10
 
-#define ORDER_METHOD_EST     0
-#define ORDER_METHOD_2LEVEL  1
-#define ORDER_METHOD_4LEVEL  2
-#define ORDER_METHOD_8LEVEL  3
-#define ORDER_METHOD_SEARCH  4
-#define ORDER_METHOD_LOG     5
-
 #define FLAC_STREAMINFO_SIZE  34
 
-#define MIN_LPC_ORDER       1
-#define MAX_LPC_ORDER      32
 #define MAX_FIXED_ORDER     4
 #define MAX_PARTITION_ORDER 8
 #define MAX_PARTITIONS     (1 << MAX_PARTITION_ORDER)
@@ -635,185 +627,6 @@ void ff_flac_compute_autocorr(const int3
     }
 }
 
-/**
- * Levinson-Durbin recursion.
- * Produces LPC coefficients from autocorrelation data.
- */
-static void compute_lpc_coefs(const double *autoc, int max_order,
-                              double lpc[][MAX_LPC_ORDER], double *ref)
-{
-   int i, j, i2;
-   double r, err, tmp;
-   double lpc_tmp[MAX_LPC_ORDER];
-
-   for(i=0; i<max_order; i++) lpc_tmp[i] = 0;
-   err = autoc[0];
-
-   for(i=0; i<max_order; i++) {
-      r = -autoc[i+1];
-      for(j=0; j<i; j++) {
-          r -= lpc_tmp[j] * autoc[i-j];
-      }
-      r /= err;
-      ref[i] = fabs(r);
-
-      err *= 1.0 - (r * r);
-
-      i2 = (i >> 1);
-      lpc_tmp[i] = r;
-      for(j=0; j<i2; j++) {
-         tmp = lpc_tmp[j];
-         lpc_tmp[j] += r * lpc_tmp[i-1-j];
-         lpc_tmp[i-1-j] += r * tmp;
-      }
-      if(i & 1) {
-          lpc_tmp[j] += lpc_tmp[j] * r;
-      }
-
-      for(j=0; j<=i; j++) {
-          lpc[i][j] = -lpc_tmp[j];
-      }
-   }
-}
-
-/**
- * Quantize LPC coefficients
- */
-static void quantize_lpc_coefs(double *lpc_in, int order, int precision,
-                               int32_t *lpc_out, int *shift, int max_shift, int zero_shift)
-{
-    int i;
-    double cmax, error;
-    int32_t qmax;
-    int sh;
-
-    /* define maximum levels */
-    qmax = (1 << (precision - 1)) - 1;
-
-    /* find maximum coefficient value */
-    cmax = 0.0;
-    for(i=0; i<order; i++) {
-        cmax= FFMAX(cmax, fabs(lpc_in[i]));
-    }
-
-    /* if maximum value quantizes to zero, return all zeros */
-    if(cmax * (1 << max_shift) < 1.0) {
-        *shift = zero_shift;
-        memset(lpc_out, 0, sizeof(int32_t) * order);
-        return;
-    }
-
-    /* calculate level shift which scales max coeff to available bits */
-    sh = max_shift;
-    while((cmax * (1 << sh) > qmax) && (sh > 0)) {
-        sh--;
-    }
-
-    /* since negative shift values are unsupported in decoder, scale down
-       coefficients instead */
-    if(sh == 0 && cmax > qmax) {
-        double scale = ((double)qmax) / cmax;
-        for(i=0; i<order; i++) {
-            lpc_in[i] *= scale;
-        }
-    }
-
-    /* output quantized coefficients and level shift */
-    error=0;
-    for(i=0; i<order; i++) {
-        error += lpc_in[i] * (1 << sh);
-        lpc_out[i] = av_clip(lrintf(error), -qmax, qmax);
-        error -= lpc_out[i];
-    }
-    *shift = sh;
-}
-
-static int estimate_best_order(double *ref, int max_order)
-{
-    int i, est;
-
-    est = 1;
-    for(i=max_order-1; i>=0; i--) {
-        if(ref[i] > 0.10) {
-            est = i+1;
-            break;
-        }
-    }
-    return est;
-}
-
-/**
- * Calculate LPC coefficients for multiple orders
- */
-static int lpc_calc_coefs(DSPContext *s,
-                          const int32_t *samples, int blocksize, int max_order,
-                          int precision, int32_t coefs[][MAX_LPC_ORDER],
-                          int *shift, int use_lpc, int omethod, int max_shift, int zero_shift)
-{
-    double autoc[MAX_LPC_ORDER+1];
-    double ref[MAX_LPC_ORDER];
-    double lpc[MAX_LPC_ORDER][MAX_LPC_ORDER];
-    int i, j, pass;
-    int opt_order;
-
-    assert(max_order >= MIN_LPC_ORDER && max_order <= MAX_LPC_ORDER);
-
-    if(use_lpc == 1){
-        s->flac_compute_autocorr(samples, blocksize, max_order, autoc);
-
-        compute_lpc_coefs(autoc, max_order, lpc, ref);
-    }else{
-        LLSModel m[2];
-        double var[MAX_LPC_ORDER+1], weight;
-
-        for(pass=0; pass<use_lpc-1; pass++){
-            av_init_lls(&m[pass&1], max_order);
-
-            weight=0;
-            for(i=max_order; i<blocksize; i++){
-                for(j=0; j<=max_order; j++)
-                    var[j]= samples[i-j];
-
-                if(pass){
-                    double eval, inv, rinv;
-                    eval= av_evaluate_lls(&m[(pass-1)&1], var+1, max_order-1);
-                    eval= (512>>pass) + fabs(eval - var[0]);
-                    inv = 1/eval;
-                    rinv = sqrt(inv);
-                    for(j=0; j<=max_order; j++)
-                        var[j] *= rinv;
-                    weight += inv;
-                }else
-                    weight++;
-
-                av_update_lls(&m[pass&1], var, 1.0);
-            }
-            av_solve_lls(&m[pass&1], 0.001, 0);
-        }
-
-        for(i=0; i<max_order; i++){
-            for(j=0; j<max_order; j++)
-                lpc[i][j]= m[(pass-1)&1].coeff[i][j];
-            ref[i]= sqrt(m[(pass-1)&1].variance[i] / weight) * (blocksize - max_order) / 4000;
-        }
-        for(i=max_order-1; i>0; i--)
-            ref[i] = ref[i-1] - ref[i];
-    }
-    opt_order = max_order;
-
-    if(omethod == ORDER_METHOD_EST) {
-        opt_order = estimate_best_order(ref, max_order);
-        i = opt_order-1;
-        quantize_lpc_coefs(lpc[i], i+1, precision, coefs[i], &shift[i], max_shift, zero_shift);
-    } else {
-        for(i=0; i<max_order; i++) {
-            quantize_lpc_coefs(lpc[i], i+1, precision, coefs[i], &shift[i], max_shift, zero_shift);
-        }
-    }
-
-    return opt_order;
-}
-
 
 static void encode_residual_verbatim(int32_t *res, int32_t *smp, int n)
 {
@@ -1042,7 +855,7 @@ static int encode_residual(FlacEncodeCon
     }
 
     /* LPC */
-    opt_order = lpc_calc_coefs(&ctx->dsp, smp, n, max_order, precision, coefs,
+    opt_order = ff_lpc_calc_coefs(&ctx->dsp, smp, n, max_order, precision, coefs,
                                shift, ctx->options.use_lpc, omethod, MAX_LPC_SHIFT, 0);
 
     if(omethod == ORDER_METHOD_2LEVEL ||

Copied: trunk/libavcodec/lpc.c (from r14789, /trunk/libavcodec/flacenc.c)
==============================================================================
--- /trunk/libavcodec/flacenc.c	(original)
+++ trunk/libavcodec/lpc.c	Sat Aug 16 19:18:20 2008
@@ -1,5 +1,5 @@
 /**
- * FLAC audio encoder
+ * LPC utility code
  * Copyright (c) 2006  Justin Ruggles <jruggle at earthlink.net>
  *
  * This file is part of FFmpeg.
@@ -19,621 +19,10 @@
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
-#include "libavutil/crc.h"
 #include "libavutil/lls.h"
-#include "avcodec.h"
-#include "bitstream.h"
 #include "dsputil.h"
-#include "golomb.h"
-
-#define FLAC_MAX_CH  8
-#define FLAC_MIN_BLOCKSIZE  16
-#define FLAC_MAX_BLOCKSIZE  65535
-
-#define FLAC_SUBFRAME_CONSTANT  0
-#define FLAC_SUBFRAME_VERBATIM  1
-#define FLAC_SUBFRAME_FIXED     8
-#define FLAC_SUBFRAME_LPC      32
-
-#define FLAC_CHMODE_NOT_STEREO      0
-#define FLAC_CHMODE_LEFT_RIGHT      1
-#define FLAC_CHMODE_LEFT_SIDE       8
-#define FLAC_CHMODE_RIGHT_SIDE      9
-#define FLAC_CHMODE_MID_SIDE       10
-
-#define ORDER_METHOD_EST     0
-#define ORDER_METHOD_2LEVEL  1
-#define ORDER_METHOD_4LEVEL  2
-#define ORDER_METHOD_8LEVEL  3
-#define ORDER_METHOD_SEARCH  4
-#define ORDER_METHOD_LOG     5
-
-#define FLAC_STREAMINFO_SIZE  34
-
-#define MIN_LPC_ORDER       1
-#define MAX_LPC_ORDER      32
-#define MAX_FIXED_ORDER     4
-#define MAX_PARTITION_ORDER 8
-#define MAX_PARTITIONS     (1 << MAX_PARTITION_ORDER)
-#define MAX_LPC_PRECISION  15
-#define MAX_LPC_SHIFT      15
-#define MAX_RICE_PARAM     14
-
-typedef struct CompressionOptions {
-    int compression_level;
-    int block_time_ms;
-    int use_lpc;
-    int lpc_coeff_precision;
-    int min_prediction_order;
-    int max_prediction_order;
-    int prediction_order_method;
-    int min_partition_order;
-    int max_partition_order;
-} CompressionOptions;
-
-typedef struct RiceContext {
-    int porder;
-    int params[MAX_PARTITIONS];
-} RiceContext;
-
-typedef struct FlacSubframe {
-    int type;
-    int type_code;
-    int obits;
-    int order;
-    int32_t coefs[MAX_LPC_ORDER];
-    int shift;
-    RiceContext rc;
-    int32_t samples[FLAC_MAX_BLOCKSIZE];
-    int32_t residual[FLAC_MAX_BLOCKSIZE+1];
-} FlacSubframe;
-
-typedef struct FlacFrame {
-    FlacSubframe subframes[FLAC_MAX_CH];
-    int blocksize;
-    int bs_code[2];
-    uint8_t crc8;
-    int ch_mode;
-} FlacFrame;
-
-typedef struct FlacEncodeContext {
-    PutBitContext pb;
-    int channels;
-    int ch_code;
-    int samplerate;
-    int sr_code[2];
-    int max_framesize;
-    uint32_t frame_count;
-    FlacFrame frame;
-    CompressionOptions options;
-    AVCodecContext *avctx;
-    DSPContext dsp;
-} FlacEncodeContext;
-
-static const int flac_samplerates[16] = {
-    0, 0, 0, 0,
-    8000, 16000, 22050, 24000, 32000, 44100, 48000, 96000,
-    0, 0, 0, 0
-};
-
-static const int flac_blocksizes[16] = {
-    0,
-    192,
-    576, 1152, 2304, 4608,
-    0, 0,
-    256, 512, 1024, 2048, 4096, 8192, 16384, 32768
-};
-
-/**
- * Writes streaminfo metadata block to byte array
- */
-static void write_streaminfo(FlacEncodeContext *s, uint8_t *header)
-{
-    PutBitContext pb;
-
-    memset(header, 0, FLAC_STREAMINFO_SIZE);
-    init_put_bits(&pb, header, FLAC_STREAMINFO_SIZE);
-
-    /* streaminfo metadata block */
-    put_bits(&pb, 16, s->avctx->frame_size);
-    put_bits(&pb, 16, s->avctx->frame_size);
-    put_bits(&pb, 24, 0);
-    put_bits(&pb, 24, s->max_framesize);
-    put_bits(&pb, 20, s->samplerate);
-    put_bits(&pb, 3, s->channels-1);
-    put_bits(&pb, 5, 15);       /* bits per sample - 1 */
-    flush_put_bits(&pb);
-    /* total samples = 0 */
-    /* MD5 signature = 0 */
-}
-
-/**
- * Sets blocksize based on samplerate
- * Chooses the closest predefined blocksize >= BLOCK_TIME_MS milliseconds
- */
-static int select_blocksize(int samplerate, int block_time_ms)
-{
-    int i;
-    int target;
-    int blocksize;
-
-    assert(samplerate > 0);
-    blocksize = flac_blocksizes[1];
-    target = (samplerate * block_time_ms) / 1000;
-    for(i=0; i<16; i++) {
-        if(target >= flac_blocksizes[i] && flac_blocksizes[i] > blocksize) {
-            blocksize = flac_blocksizes[i];
-        }
-    }
-    return blocksize;
-}
-
-static av_cold int flac_encode_init(AVCodecContext *avctx)
-{
-    int freq = avctx->sample_rate;
-    int channels = avctx->channels;
-    FlacEncodeContext *s = avctx->priv_data;
-    int i, level;
-    uint8_t *streaminfo;
-
-    s->avctx = avctx;
-
-    dsputil_init(&s->dsp, avctx);
-
-    if(avctx->sample_fmt != SAMPLE_FMT_S16) {
-        return -1;
-    }
-
-    if(channels < 1 || channels > FLAC_MAX_CH) {
-        return -1;
-    }
-    s->channels = channels;
-    s->ch_code = s->channels-1;
-
-    /* find samplerate in table */
-    if(freq < 1)
-        return -1;
-    for(i=4; i<12; i++) {
-        if(freq == flac_samplerates[i]) {
-            s->samplerate = flac_samplerates[i];
-            s->sr_code[0] = i;
-            s->sr_code[1] = 0;
-            break;
-        }
-    }
-    /* if not in table, samplerate is non-standard */
-    if(i == 12) {
-        if(freq % 1000 == 0 && freq < 255000) {
-            s->sr_code[0] = 12;
-            s->sr_code[1] = freq / 1000;
-        } else if(freq % 10 == 0 && freq < 655350) {
-            s->sr_code[0] = 14;
-            s->sr_code[1] = freq / 10;
-        } else if(freq < 65535) {
-            s->sr_code[0] = 13;
-            s->sr_code[1] = freq;
-        } else {
-            return -1;
-        }
-        s->samplerate = freq;
-    }
-
-    /* set compression option defaults based on avctx->compression_level */
-    if(avctx->compression_level < 0) {
-        s->options.compression_level = 5;
-    } else {
-        s->options.compression_level = avctx->compression_level;
-    }
-    av_log(avctx, AV_LOG_DEBUG, " compression: %d\n", s->options.compression_level);
-
-    level= s->options.compression_level;
-    if(level > 12) {
-        av_log(avctx, AV_LOG_ERROR, "invalid compression level: %d\n",
-               s->options.compression_level);
-        return -1;
-    }
-
-    s->options.block_time_ms       = ((int[]){ 27, 27, 27,105,105,105,105,105,105,105,105,105,105})[level];
-    s->options.use_lpc             = ((int[]){  0,  0,  0,  1,  1,  1,  1,  1,  1,  1,  1,  1,  1})[level];
-    s->options.min_prediction_order= ((int[]){  2,  0,  0,  1,  1,  1,  1,  1,  1,  1,  1,  1,  1})[level];
-    s->options.max_prediction_order= ((int[]){  3,  4,  4,  6,  8,  8,  8,  8, 12, 12, 12, 32, 32})[level];
-    s->options.prediction_order_method = ((int[]){ ORDER_METHOD_EST,    ORDER_METHOD_EST,    ORDER_METHOD_EST,
-                                                   ORDER_METHOD_EST,    ORDER_METHOD_EST,    ORDER_METHOD_EST,
-                                                   ORDER_METHOD_4LEVEL, ORDER_METHOD_LOG,    ORDER_METHOD_4LEVEL,
-                                                   ORDER_METHOD_LOG,    ORDER_METHOD_SEARCH, ORDER_METHOD_LOG,
-                                                   ORDER_METHOD_SEARCH})[level];
-    s->options.min_partition_order = ((int[]){  2,  2,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0})[level];
-    s->options.max_partition_order = ((int[]){  2,  2,  3,  3,  3,  8,  8,  8,  8,  8,  8,  8,  8})[level];
-
-    /* set compression option overrides from AVCodecContext */
-    if(avctx->use_lpc >= 0) {
-        s->options.use_lpc = av_clip(avctx->use_lpc, 0, 11);
-    }
-    if(s->options.use_lpc == 1)
-        av_log(avctx, AV_LOG_DEBUG, " use lpc: Levinson-Durbin recursion with Welch window\n");
-    else if(s->options.use_lpc > 1)
-        av_log(avctx, AV_LOG_DEBUG, " use lpc: Cholesky factorization\n");
-
-    if(avctx->min_prediction_order >= 0) {
-        if(s->options.use_lpc) {
-            if(avctx->min_prediction_order < MIN_LPC_ORDER ||
-                    avctx->min_prediction_order > MAX_LPC_ORDER) {
-                av_log(avctx, AV_LOG_ERROR, "invalid min prediction order: %d\n",
-                       avctx->min_prediction_order);
-                return -1;
-            }
-        } else {
-            if(avctx->min_prediction_order > MAX_FIXED_ORDER) {
-                av_log(avctx, AV_LOG_ERROR, "invalid min prediction order: %d\n",
-                       avctx->min_prediction_order);
-                return -1;
-            }
-        }
-        s->options.min_prediction_order = avctx->min_prediction_order;
-    }
-    if(avctx->max_prediction_order >= 0) {
-        if(s->options.use_lpc) {
-            if(avctx->max_prediction_order < MIN_LPC_ORDER ||
-                    avctx->max_prediction_order > MAX_LPC_ORDER) {
-                av_log(avctx, AV_LOG_ERROR, "invalid max prediction order: %d\n",
-                       avctx->max_prediction_order);
-                return -1;
-            }
-        } else {
-            if(avctx->max_prediction_order > MAX_FIXED_ORDER) {
-                av_log(avctx, AV_LOG_ERROR, "invalid max prediction order: %d\n",
-                       avctx->max_prediction_order);
-                return -1;
-            }
-        }
-        s->options.max_prediction_order = avctx->max_prediction_order;
-    }
-    if(s->options.max_prediction_order < s->options.min_prediction_order) {
-        av_log(avctx, AV_LOG_ERROR, "invalid prediction orders: min=%d max=%d\n",
-               s->options.min_prediction_order, s->options.max_prediction_order);
-        return -1;
-    }
-    av_log(avctx, AV_LOG_DEBUG, " prediction order: %d, %d\n",
-           s->options.min_prediction_order, s->options.max_prediction_order);
-
-    if(avctx->prediction_order_method >= 0) {
-        if(avctx->prediction_order_method > ORDER_METHOD_LOG) {
-            av_log(avctx, AV_LOG_ERROR, "invalid prediction order method: %d\n",
-                   avctx->prediction_order_method);
-            return -1;
-        }
-        s->options.prediction_order_method = avctx->prediction_order_method;
-    }
-    switch(s->options.prediction_order_method) {
-        case ORDER_METHOD_EST:    av_log(avctx, AV_LOG_DEBUG, " order method: %s\n",
-                                         "estimate"); break;
-        case ORDER_METHOD_2LEVEL: av_log(avctx, AV_LOG_DEBUG, " order method: %s\n",
-                                         "2-level"); break;
-        case ORDER_METHOD_4LEVEL: av_log(avctx, AV_LOG_DEBUG, " order method: %s\n",
-                                         "4-level"); break;
-        case ORDER_METHOD_8LEVEL: av_log(avctx, AV_LOG_DEBUG, " order method: %s\n",
-                                         "8-level"); break;
-        case ORDER_METHOD_SEARCH: av_log(avctx, AV_LOG_DEBUG, " order method: %s\n",
-                                         "full search"); break;
-        case ORDER_METHOD_LOG:    av_log(avctx, AV_LOG_DEBUG, " order method: %s\n",
-                                         "log search"); break;
-    }
-
-    if(avctx->min_partition_order >= 0) {
-        if(avctx->min_partition_order > MAX_PARTITION_ORDER) {
-            av_log(avctx, AV_LOG_ERROR, "invalid min partition order: %d\n",
-                   avctx->min_partition_order);
-            return -1;
-        }
-        s->options.min_partition_order = avctx->min_partition_order;
-    }
-    if(avctx->max_partition_order >= 0) {
-        if(avctx->max_partition_order > MAX_PARTITION_ORDER) {
-            av_log(avctx, AV_LOG_ERROR, "invalid max partition order: %d\n",
-                   avctx->max_partition_order);
-            return -1;
-        }
-        s->options.max_partition_order = avctx->max_partition_order;
-    }
-    if(s->options.max_partition_order < s->options.min_partition_order) {
-        av_log(avctx, AV_LOG_ERROR, "invalid partition orders: min=%d max=%d\n",
-               s->options.min_partition_order, s->options.max_partition_order);
-        return -1;
-    }
-    av_log(avctx, AV_LOG_DEBUG, " partition order: %d, %d\n",
-           s->options.min_partition_order, s->options.max_partition_order);
-
-    if(avctx->frame_size > 0) {
-        if(avctx->frame_size < FLAC_MIN_BLOCKSIZE ||
-                avctx->frame_size > FLAC_MAX_BLOCKSIZE) {
-            av_log(avctx, AV_LOG_ERROR, "invalid block size: %d\n",
-                   avctx->frame_size);
-            return -1;
-        }
-    } else {
-        s->avctx->frame_size = select_blocksize(s->samplerate, s->options.block_time_ms);
-    }
-    av_log(avctx, AV_LOG_DEBUG, " block size: %d\n", s->avctx->frame_size);
-
-    /* set LPC precision */
-    if(avctx->lpc_coeff_precision > 0) {
-        if(avctx->lpc_coeff_precision > MAX_LPC_PRECISION) {
-            av_log(avctx, AV_LOG_ERROR, "invalid lpc coeff precision: %d\n",
-                   avctx->lpc_coeff_precision);
-            return -1;
-        }
-        s->options.lpc_coeff_precision = avctx->lpc_coeff_precision;
-    } else {
-        /* default LPC precision */
-        s->options.lpc_coeff_precision = 15;
-    }
-    av_log(avctx, AV_LOG_DEBUG, " lpc precision: %d\n",
-           s->options.lpc_coeff_precision);
-
-    /* set maximum encoded frame size in verbatim mode */
-    if(s->channels == 2) {
-        s->max_framesize = 14 + ((s->avctx->frame_size * 33 + 7) >> 3);
-    } else {
-        s->max_framesize = 14 + (s->avctx->frame_size * s->channels * 2);
-    }
-
-    streaminfo = av_malloc(FLAC_STREAMINFO_SIZE);
-    write_streaminfo(s, streaminfo);
-    avctx->extradata = streaminfo;
-    avctx->extradata_size = FLAC_STREAMINFO_SIZE;
-
-    s->frame_count = 0;
-
-    avctx->coded_frame = avcodec_alloc_frame();
-    avctx->coded_frame->key_frame = 1;
-
-    return 0;
-}
-
-static void init_frame(FlacEncodeContext *s)
-{
-    int i, ch;
-    FlacFrame *frame;
-
-    frame = &s->frame;
-
-    for(i=0; i<16; i++) {
-        if(s->avctx->frame_size == flac_blocksizes[i]) {
-            frame->blocksize = flac_blocksizes[i];
-            frame->bs_code[0] = i;
-            frame->bs_code[1] = 0;
-            break;
-        }
-    }
-    if(i == 16) {
-        frame->blocksize = s->avctx->frame_size;
-        if(frame->blocksize <= 256) {
-            frame->bs_code[0] = 6;
-            frame->bs_code[1] = frame->blocksize-1;
-        } else {
-            frame->bs_code[0] = 7;
-            frame->bs_code[1] = frame->blocksize-1;
-        }
-    }
-
-    for(ch=0; ch<s->channels; ch++) {
-        frame->subframes[ch].obits = 16;
-    }
-}
-
-/**
- * Copy channel-interleaved input samples into separate subframes
- */
-static void copy_samples(FlacEncodeContext *s, int16_t *samples)
-{
-    int i, j, ch;
-    FlacFrame *frame;
-
-    frame = &s->frame;
-    for(i=0,j=0; i<frame->blocksize; i++) {
-        for(ch=0; ch<s->channels; ch++,j++) {
-            frame->subframes[ch].samples[i] = samples[j];
-        }
-    }
-}
-
-
-#define rice_encode_count(sum, n, k) (((n)*((k)+1))+((sum-(n>>1))>>(k)))
-
-/**
- * Solve for d/dk(rice_encode_count) = n-((sum-(n>>1))>>(k+1)) = 0
- */
-static int find_optimal_param(uint32_t sum, int n)
-{
-    int k;
-    uint32_t sum2;
-
-    if(sum <= n>>1)
-        return 0;
-    sum2 = sum-(n>>1);
-    k = av_log2(n<256 ? FASTDIV(sum2,n) : sum2/n);
-    return FFMIN(k, MAX_RICE_PARAM);
-}
-
-static uint32_t calc_optimal_rice_params(RiceContext *rc, int porder,
-                                         uint32_t *sums, int n, int pred_order)
-{
-    int i;
-    int k, cnt, part;
-    uint32_t all_bits;
-
-    part = (1 << porder);
-    all_bits = 4 * part;
-
-    cnt = (n >> porder) - pred_order;
-    for(i=0; i<part; i++) {
-        k = find_optimal_param(sums[i], cnt);
-        rc->params[i] = k;
-        all_bits += rice_encode_count(sums[i], cnt, k);
-        cnt = n >> porder;
-    }
-
-    rc->porder = porder;
-
-    return all_bits;
-}
-
-static void calc_sums(int pmin, int pmax, uint32_t *data, int n, int pred_order,
-                      uint32_t sums[][MAX_PARTITIONS])
-{
-    int i, j;
-    int parts;
-    uint32_t *res, *res_end;
-
-    /* sums for highest level */
-    parts = (1 << pmax);
-    res = &data[pred_order];
-    res_end = &data[n >> pmax];
-    for(i=0; i<parts; i++) {
-        uint32_t sum = 0;
-        while(res < res_end){
-            sum += *(res++);
-        }
-        sums[pmax][i] = sum;
-        res_end+= n >> pmax;
-    }
-    /* sums for lower levels */
-    for(i=pmax-1; i>=pmin; i--) {
-        parts = (1 << i);
-        for(j=0; j<parts; j++) {
-            sums[i][j] = sums[i+1][2*j] + sums[i+1][2*j+1];
-        }
-    }
-}
-
-static uint32_t calc_rice_params(RiceContext *rc, int pmin, int pmax,
-                                 int32_t *data, int n, int pred_order)
-{
-    int i;
-    uint32_t bits[MAX_PARTITION_ORDER+1];
-    int opt_porder;
-    RiceContext tmp_rc;
-    uint32_t *udata;
-    uint32_t sums[MAX_PARTITION_ORDER+1][MAX_PARTITIONS];
-
-    assert(pmin >= 0 && pmin <= MAX_PARTITION_ORDER);
-    assert(pmax >= 0 && pmax <= MAX_PARTITION_ORDER);
-    assert(pmin <= pmax);
-
-    udata = av_malloc(n * sizeof(uint32_t));
-    for(i=0; i<n; i++) {
-        udata[i] = (2*data[i]) ^ (data[i]>>31);
-    }
-
-    calc_sums(pmin, pmax, udata, n, pred_order, sums);
-
-    opt_porder = pmin;
-    bits[pmin] = UINT32_MAX;
-    for(i=pmin; i<=pmax; i++) {
-        bits[i] = calc_optimal_rice_params(&tmp_rc, i, sums[i], n, pred_order);
-        if(bits[i] <= bits[opt_porder]) {
-            opt_porder = i;
-            *rc= tmp_rc;
-        }
-    }
-
-    av_freep(&udata);
-    return bits[opt_porder];
-}
-
-static int get_max_p_order(int max_porder, int n, int order)
-{
-    int porder = FFMIN(max_porder, av_log2(n^(n-1)));
-    if(order > 0)
-        porder = FFMIN(porder, av_log2(n/order));
-    return porder;
-}
-
-static uint32_t calc_rice_params_fixed(RiceContext *rc, int pmin, int pmax,
-                                       int32_t *data, int n, int pred_order,
-                                       int bps)
-{
-    uint32_t bits;
-    pmin = get_max_p_order(pmin, n, pred_order);
-    pmax = get_max_p_order(pmax, n, pred_order);
-    bits = pred_order*bps + 6;
-    bits += calc_rice_params(rc, pmin, pmax, data, n, pred_order);
-    return bits;
-}
-
-static uint32_t calc_rice_params_lpc(RiceContext *rc, int pmin, int pmax,
-                                     int32_t *data, int n, int pred_order,
-                                     int bps, int precision)
-{
-    uint32_t bits;
-    pmin = get_max_p_order(pmin, n, pred_order);
-    pmax = get_max_p_order(pmax, n, pred_order);
-    bits = pred_order*bps + 4 + 5 + pred_order*precision + 6;
-    bits += calc_rice_params(rc, pmin, pmax, data, n, pred_order);
-    return bits;
-}
-
-/**
- * Apply Welch window function to audio block
- */
-static void apply_welch_window(const int32_t *data, int len, double *w_data)
-{
-    int i, n2;
-    double w;
-    double c;
-
-    assert(!(len&1)); //the optimization in r11881 does not support odd len
-                      //if someone wants odd len extend the change in r11881
-
-    n2 = (len >> 1);
-    c = 2.0 / (len - 1.0);
-
-    w_data+=n2;
-      data+=n2;
-    for(i=0; i<n2; i++) {
-        w = c - n2 + i;
-        w = 1.0 - (w * w);
-        w_data[-i-1] = data[-i-1] * w;
-        w_data[+i  ] = data[+i  ] * w;
-    }
-}
-
-/**
- * Calculates autocorrelation data from audio samples
- * A Welch window function is applied before calculation.
- */
-void ff_flac_compute_autocorr(const int32_t *data, int len, int lag,
-                              double *autoc)
-{
-    int i, j;
-    double tmp[len + lag + 1];
-    double *data1= tmp + lag;
-
-    apply_welch_window(data, len, data1);
-
-    for(j=0; j<lag; j++)
-        data1[j-lag]= 0.0;
-    data1[len] = 0.0;
-
-    for(j=0; j<lag; j+=2){
-        double sum0 = 1.0, sum1 = 1.0;
-        for(i=0; i<len; i++){
-            sum0 += data1[i] * data1[i-j];
-            sum1 += data1[i] * data1[i-j-1];
-        }
-        autoc[j  ] = sum0;
-        autoc[j+1] = sum1;
-    }
+#include "lpc.h"
 
-    if(j==lag){
-        double sum = 1.0;
-        for(i=0; i<len; i+=2){
-            sum += data1[i  ] * data1[i-j  ]
-                 + data1[i+1] * data1[i-j+1];
-        }
-        autoc[j] = sum;
-    }
-}
 
 /**
  * Levinson-Durbin recursion.
@@ -745,7 +134,7 @@ static int estimate_best_order(double *r
 /**
  * Calculate LPC coefficients for multiple orders
  */
-static int lpc_calc_coefs(DSPContext *s,
+int ff_lpc_calc_coefs(DSPContext *s,
                           const int32_t *samples, int blocksize, int max_order,
                           int precision, int32_t coefs[][MAX_LPC_ORDER],
                           int *shift, int use_lpc, int omethod, int max_shift, int zero_shift)
@@ -813,679 +202,3 @@ static int lpc_calc_coefs(DSPContext *s,
 
     return opt_order;
 }
-
-
-static void encode_residual_verbatim(int32_t *res, int32_t *smp, int n)
-{
-    assert(n > 0);
-    memcpy(res, smp, n * sizeof(int32_t));
-}
-
-static void encode_residual_fixed(int32_t *res, const int32_t *smp, int n,
-                                  int order)
-{
-    int i;
-
-    for(i=0; i<order; i++) {
-        res[i] = smp[i];
-    }
-
-    if(order==0){
-        for(i=order; i<n; i++)
-            res[i]= smp[i];
-    }else if(order==1){
-        for(i=order; i<n; i++)
-            res[i]= smp[i] - smp[i-1];
-    }else if(order==2){
-        int a = smp[order-1] - smp[order-2];
-        for(i=order; i<n; i+=2) {
-            int b = smp[i] - smp[i-1];
-            res[i]= b - a;
-            a = smp[i+1] - smp[i];
-            res[i+1]= a - b;
-        }
-    }else if(order==3){
-        int a = smp[order-1] - smp[order-2];
-        int c = smp[order-1] - 2*smp[order-2] + smp[order-3];
-        for(i=order; i<n; i+=2) {
-            int b = smp[i] - smp[i-1];
-            int d = b - a;
-            res[i]= d - c;
-            a = smp[i+1] - smp[i];
-            c = a - b;
-            res[i+1]= c - d;
-        }
-    }else{
-        int a = smp[order-1] - smp[order-2];
-        int c = smp[order-1] - 2*smp[order-2] + smp[order-3];
-        int e = smp[order-1] - 3*smp[order-2] + 3*smp[order-3] - smp[order-4];
-        for(i=order; i<n; i+=2) {
-            int b = smp[i] - smp[i-1];
-            int d = b - a;
-            int f = d - c;
-            res[i]= f - e;
-            a = smp[i+1] - smp[i];
-            c = a - b;
-            e = c - d;
-            res[i+1]= e - f;
-        }
-    }
-}
-
-#define LPC1(x) {\
-    int c = coefs[(x)-1];\
-    p0 += c*s;\
-    s = smp[i-(x)+1];\
-    p1 += c*s;\
-}
-
-static av_always_inline void encode_residual_lpc_unrolled(
-    int32_t *res, const int32_t *smp, int n,
-    int order, const int32_t *coefs, int shift, int big)
-{
-    int i;
-    for(i=order; i<n; i+=2) {
-        int s = smp[i-order];
-        int p0 = 0, p1 = 0;
-        if(big) {
-            switch(order) {
-                case 32: LPC1(32)
-                case 31: LPC1(31)
-                case 30: LPC1(30)
-                case 29: LPC1(29)
-                case 28: LPC1(28)
-                case 27: LPC1(27)
-                case 26: LPC1(26)
-                case 25: LPC1(25)
-                case 24: LPC1(24)
-                case 23: LPC1(23)
-                case 22: LPC1(22)
-                case 21: LPC1(21)
-                case 20: LPC1(20)
-                case 19: LPC1(19)
-                case 18: LPC1(18)
-                case 17: LPC1(17)
-                case 16: LPC1(16)
-                case 15: LPC1(15)
-                case 14: LPC1(14)
-                case 13: LPC1(13)
-                case 12: LPC1(12)
-                case 11: LPC1(11)
-                case 10: LPC1(10)
-                case  9: LPC1( 9)
-                         LPC1( 8)
-                         LPC1( 7)
-                         LPC1( 6)
-                         LPC1( 5)
-                         LPC1( 4)
-                         LPC1( 3)
-                         LPC1( 2)
-                         LPC1( 1)
-            }
-        } else {
-            switch(order) {
-                case  8: LPC1( 8)
-                case  7: LPC1( 7)
-                case  6: LPC1( 6)
-                case  5: LPC1( 5)
-                case  4: LPC1( 4)
-                case  3: LPC1( 3)
-                case  2: LPC1( 2)
-                case  1: LPC1( 1)
-            }
-        }
-        res[i  ] = smp[i  ] - (p0 >> shift);
-        res[i+1] = smp[i+1] - (p1 >> shift);
-    }
-}
-
-static void encode_residual_lpc(int32_t *res, const int32_t *smp, int n,
-                                int order, const int32_t *coefs, int shift)
-{
-    int i;
-    for(i=0; i<order; i++) {
-        res[i] = smp[i];
-    }
-#ifdef CONFIG_SMALL
-    for(i=order; i<n; i+=2) {
-        int j;
-        int s = smp[i];
-        int p0 = 0, p1 = 0;
-        for(j=0; j<order; j++) {
-            int c = coefs[j];
-            p1 += c*s;
-            s = smp[i-j-1];
-            p0 += c*s;
-        }
-        res[i  ] = smp[i  ] - (p0 >> shift);
-        res[i+1] = smp[i+1] - (p1 >> shift);
-    }
-#else
-    switch(order) {
-        case  1: encode_residual_lpc_unrolled(res, smp, n, 1, coefs, shift, 0); break;
-        case  2: encode_residual_lpc_unrolled(res, smp, n, 2, coefs, shift, 0); break;
-        case  3: encode_residual_lpc_unrolled(res, smp, n, 3, coefs, shift, 0); break;
-        case  4: encode_residual_lpc_unrolled(res, smp, n, 4, coefs, shift, 0); break;
-        case  5: encode_residual_lpc_unrolled(res, smp, n, 5, coefs, shift, 0); break;
-        case  6: encode_residual_lpc_unrolled(res, smp, n, 6, coefs, shift, 0); break;
-        case  7: encode_residual_lpc_unrolled(res, smp, n, 7, coefs, shift, 0); break;
-        case  8: encode_residual_lpc_unrolled(res, smp, n, 8, coefs, shift, 0); break;
-        default: encode_residual_lpc_unrolled(res, smp, n, order, coefs, shift, 1); break;
-    }
-#endif
-}
-
-static int encode_residual(FlacEncodeContext *ctx, int ch)
-{
-    int i, n;
-    int min_order, max_order, opt_order, precision, omethod;
-    int min_porder, max_porder;
-    FlacFrame *frame;
-    FlacSubframe *sub;
-    int32_t coefs[MAX_LPC_ORDER][MAX_LPC_ORDER];
-    int shift[MAX_LPC_ORDER];
-    int32_t *res, *smp;
-
-    frame = &ctx->frame;
-    sub = &frame->subframes[ch];
-    res = sub->residual;
-    smp = sub->samples;
-    n = frame->blocksize;
-
-    /* CONSTANT */
-    for(i=1; i<n; i++) {
-        if(smp[i] != smp[0]) break;
-    }
-    if(i == n) {
-        sub->type = sub->type_code = FLAC_SUBFRAME_CONSTANT;
-        res[0] = smp[0];
-        return sub->obits;
-    }
-
-    /* VERBATIM */
-    if(n < 5) {
-        sub->type = sub->type_code = FLAC_SUBFRAME_VERBATIM;
-        encode_residual_verbatim(res, smp, n);
-        return sub->obits * n;
-    }
-
-    min_order = ctx->options.min_prediction_order;
-    max_order = ctx->options.max_prediction_order;
-    min_porder = ctx->options.min_partition_order;
-    max_porder = ctx->options.max_partition_order;
-    precision = ctx->options.lpc_coeff_precision;
-    omethod = ctx->options.prediction_order_method;
-
-    /* FIXED */
-    if(!ctx->options.use_lpc || max_order == 0 || (n <= max_order)) {
-        uint32_t bits[MAX_FIXED_ORDER+1];
-        if(max_order > MAX_FIXED_ORDER) max_order = MAX_FIXED_ORDER;
-        opt_order = 0;
-        bits[0] = UINT32_MAX;
-        for(i=min_order; i<=max_order; i++) {
-            encode_residual_fixed(res, smp, n, i);
-            bits[i] = calc_rice_params_fixed(&sub->rc, min_porder, max_porder, res,
-                                             n, i, sub->obits);
-            if(bits[i] < bits[opt_order]) {
-                opt_order = i;
-            }
-        }
-        sub->order = opt_order;
-        sub->type = FLAC_SUBFRAME_FIXED;
-        sub->type_code = sub->type | sub->order;
-        if(sub->order != max_order) {
-            encode_residual_fixed(res, smp, n, sub->order);
-            return calc_rice_params_fixed(&sub->rc, min_porder, max_porder, res, n,
-                                          sub->order, sub->obits);
-        }
-        return bits[sub->order];
-    }
-
-    /* LPC */
-    opt_order = lpc_calc_coefs(&ctx->dsp, smp, n, max_order, precision, coefs,
-                               shift, ctx->options.use_lpc, omethod, MAX_LPC_SHIFT, 0);
-
-    if(omethod == ORDER_METHOD_2LEVEL ||
-       omethod == ORDER_METHOD_4LEVEL ||
-       omethod == ORDER_METHOD_8LEVEL) {
-        int levels = 1 << omethod;
-        uint32_t bits[levels];
-        int order;
-        int opt_index = levels-1;
-        opt_order = max_order-1;
-        bits[opt_index] = UINT32_MAX;
-        for(i=levels-1; i>=0; i--) {
-            order = min_order + (((max_order-min_order+1) * (i+1)) / levels)-1;
-            if(order < 0) order = 0;
-            encode_residual_lpc(res, smp, n, order+1, coefs[order], shift[order]);
-            bits[i] = calc_rice_params_lpc(&sub->rc, min_porder, max_porder,
-                                           res, n, order+1, sub->obits, precision);
-            if(bits[i] < bits[opt_index]) {
-                opt_index = i;
-                opt_order = order;
-            }
-        }
-        opt_order++;
-    } else if(omethod == ORDER_METHOD_SEARCH) {
-        // brute-force optimal order search
-        uint32_t bits[MAX_LPC_ORDER];
-        opt_order = 0;
-        bits[0] = UINT32_MAX;
-        for(i=min_order-1; i<max_order; i++) {
-            encode_residual_lpc(res, smp, n, i+1, coefs[i], shift[i]);
-            bits[i] = calc_rice_params_lpc(&sub->rc, min_porder, max_porder,
-                                           res, n, i+1, sub->obits, precision);
-            if(bits[i] < bits[opt_order]) {
-                opt_order = i;
-            }
-        }
-        opt_order++;
-    } else if(omethod == ORDER_METHOD_LOG) {
-        uint32_t bits[MAX_LPC_ORDER];
-        int step;
-
-        opt_order= min_order - 1 + (max_order-min_order)/3;
-        memset(bits, -1, sizeof(bits));
-
-        for(step=16 ;step; step>>=1){
-            int last= opt_order;
-            for(i=last-step; i<=last+step; i+= step){
-                if(i<min_order-1 || i>=max_order || bits[i] < UINT32_MAX)
-                    continue;
-                encode_residual_lpc(res, smp, n, i+1, coefs[i], shift[i]);
-                bits[i] = calc_rice_params_lpc(&sub->rc, min_porder, max_porder,
-                                            res, n, i+1, sub->obits, precision);
-                if(bits[i] < bits[opt_order])
-                    opt_order= i;
-            }
-        }
-        opt_order++;
-    }
-
-    sub->order = opt_order;
-    sub->type = FLAC_SUBFRAME_LPC;
-    sub->type_code = sub->type | (sub->order-1);
-    sub->shift = shift[sub->order-1];
-    for(i=0; i<sub->order; i++) {
-        sub->coefs[i] = coefs[sub->order-1][i];
-    }
-    encode_residual_lpc(res, smp, n, sub->order, sub->coefs, sub->shift);
-    return calc_rice_params_lpc(&sub->rc, min_porder, max_porder, res, n, sub->order,
-                                sub->obits, precision);
-}
-
-static int encode_residual_v(FlacEncodeContext *ctx, int ch)
-{
-    int i, n;
-    FlacFrame *frame;
-    FlacSubframe *sub;
-    int32_t *res, *smp;
-
-    frame = &ctx->frame;
-    sub = &frame->subframes[ch];
-    res = sub->residual;
-    smp = sub->samples;
-    n = frame->blocksize;
-
-    /* CONSTANT */
-    for(i=1; i<n; i++) {
-        if(smp[i] != smp[0]) break;
-    }
-    if(i == n) {
-        sub->type = sub->type_code = FLAC_SUBFRAME_CONSTANT;
-        res[0] = smp[0];
-        return sub->obits;
-    }
-
-    /* VERBATIM */
-    sub->type = sub->type_code = FLAC_SUBFRAME_VERBATIM;
-    encode_residual_verbatim(res, smp, n);
-    return sub->obits * n;
-}
-
-static int estimate_stereo_mode(int32_t *left_ch, int32_t *right_ch, int n)
-{
-    int i, best;
-    int32_t lt, rt;
-    uint64_t sum[4];
-    uint64_t score[4];
-    int k;
-
-    /* calculate sum of 2nd order residual for each channel */
-    sum[0] = sum[1] = sum[2] = sum[3] = 0;
-    for(i=2; i<n; i++) {
-        lt = left_ch[i] - 2*left_ch[i-1] + left_ch[i-2];
-        rt = right_ch[i] - 2*right_ch[i-1] + right_ch[i-2];
-        sum[2] += FFABS((lt + rt) >> 1);
-        sum[3] += FFABS(lt - rt);
-        sum[0] += FFABS(lt);
-        sum[1] += FFABS(rt);
-    }
-    /* estimate bit counts */
-    for(i=0; i<4; i++) {
-        k = find_optimal_param(2*sum[i], n);
-        sum[i] = rice_encode_count(2*sum[i], n, k);
-    }
-
-    /* calculate score for each mode */
-    score[0] = sum[0] + sum[1];
-    score[1] = sum[0] + sum[3];
-    score[2] = sum[1] + sum[3];
-    score[3] = sum[2] + sum[3];
-
-    /* return mode with lowest score */
-    best = 0;
-    for(i=1; i<4; i++) {
-        if(score[i] < score[best]) {
-            best = i;
-        }
-    }
-    if(best == 0) {
-        return FLAC_CHMODE_LEFT_RIGHT;
-    } else if(best == 1) {
-        return FLAC_CHMODE_LEFT_SIDE;
-    } else if(best == 2) {
-        return FLAC_CHMODE_RIGHT_SIDE;
-    } else {
-        return FLAC_CHMODE_MID_SIDE;
-    }
-}
-
-/**
- * Perform stereo channel decorrelation
- */
-static void channel_decorrelation(FlacEncodeContext *ctx)
-{
-    FlacFrame *frame;
-    int32_t *left, *right;
-    int i, n;
-
-    frame = &ctx->frame;
-    n = frame->blocksize;
-    left  = frame->subframes[0].samples;
-    right = frame->subframes[1].samples;
-
-    if(ctx->channels != 2) {
-        frame->ch_mode = FLAC_CHMODE_NOT_STEREO;
-        return;
-    }
-
-    frame->ch_mode = estimate_stereo_mode(left, right, n);
-
-    /* perform decorrelation and adjust bits-per-sample */
-    if(frame->ch_mode == FLAC_CHMODE_LEFT_RIGHT) {
-        return;
-    }
-    if(frame->ch_mode == FLAC_CHMODE_MID_SIDE) {
-        int32_t tmp;
-        for(i=0; i<n; i++) {
-            tmp = left[i];
-            left[i] = (tmp + right[i]) >> 1;
-            right[i] = tmp - right[i];
-        }
-        frame->subframes[1].obits++;
-    } else if(frame->ch_mode == FLAC_CHMODE_LEFT_SIDE) {
-        for(i=0; i<n; i++) {
-            right[i] = left[i] - right[i];
-        }
-        frame->subframes[1].obits++;
-    } else {
-        for(i=0; i<n; i++) {
-            left[i] -= right[i];
-        }
-        frame->subframes[0].obits++;
-    }
-}
-
-static void write_utf8(PutBitContext *pb, uint32_t val)
-{
-    uint8_t tmp;
-    PUT_UTF8(val, tmp, put_bits(pb, 8, tmp);)
-}
-
-static void output_frame_header(FlacEncodeContext *s)
-{
-    FlacFrame *frame;
-    int crc;
-
-    frame = &s->frame;
-
-    put_bits(&s->pb, 16, 0xFFF8);
-    put_bits(&s->pb, 4, frame->bs_code[0]);
-    put_bits(&s->pb, 4, s->sr_code[0]);
-    if(frame->ch_mode == FLAC_CHMODE_NOT_STEREO) {
-        put_bits(&s->pb, 4, s->ch_code);
-    } else {
-        put_bits(&s->pb, 4, frame->ch_mode);
-    }
-    put_bits(&s->pb, 3, 4); /* bits-per-sample code */
-    put_bits(&s->pb, 1, 0);
-    write_utf8(&s->pb, s->frame_count);
-    if(frame->bs_code[0] == 6) {
-        put_bits(&s->pb, 8, frame->bs_code[1]);
-    } else if(frame->bs_code[0] == 7) {
-        put_bits(&s->pb, 16, frame->bs_code[1]);
-    }
-    if(s->sr_code[0] == 12) {
-        put_bits(&s->pb, 8, s->sr_code[1]);
-    } else if(s->sr_code[0] > 12) {
-        put_bits(&s->pb, 16, s->sr_code[1]);
-    }
-    flush_put_bits(&s->pb);
-    crc = av_crc(av_crc_get_table(AV_CRC_8_ATM), 0,
-                 s->pb.buf, put_bits_count(&s->pb)>>3);
-    put_bits(&s->pb, 8, crc);
-}
-
-static void output_subframe_constant(FlacEncodeContext *s, int ch)
-{
-    FlacSubframe *sub;
-    int32_t res;
-
-    sub = &s->frame.subframes[ch];
-    res = sub->residual[0];
-    put_sbits(&s->pb, sub->obits, res);
-}
-
-static void output_subframe_verbatim(FlacEncodeContext *s, int ch)
-{
-    int i;
-    FlacFrame *frame;
-    FlacSubframe *sub;
-    int32_t res;
-
-    frame = &s->frame;
-    sub = &frame->subframes[ch];
-
-    for(i=0; i<frame->blocksize; i++) {
-        res = sub->residual[i];
-        put_sbits(&s->pb, sub->obits, res);
-    }
-}
-
-static void output_residual(FlacEncodeContext *ctx, int ch)
-{
-    int i, j, p, n, parts;
-    int k, porder, psize, res_cnt;
-    FlacFrame *frame;
-    FlacSubframe *sub;
-    int32_t *res;
-
-    frame = &ctx->frame;
-    sub = &frame->subframes[ch];
-    res = sub->residual;
-    n = frame->blocksize;
-
-    /* rice-encoded block */
-    put_bits(&ctx->pb, 2, 0);
-
-    /* partition order */
-    porder = sub->rc.porder;
-    psize = n >> porder;
-    parts = (1 << porder);
-    put_bits(&ctx->pb, 4, porder);
-    res_cnt = psize - sub->order;
-
-    /* residual */
-    j = sub->order;
-    for(p=0; p<parts; p++) {
-        k = sub->rc.params[p];
-        put_bits(&ctx->pb, 4, k);
-        if(p == 1) res_cnt = psize;
-        for(i=0; i<res_cnt && j<n; i++, j++) {
-            set_sr_golomb_flac(&ctx->pb, res[j], k, INT32_MAX, 0);
-        }
-    }
-}
-
-static void output_subframe_fixed(FlacEncodeContext *ctx, int ch)
-{
-    int i;
-    FlacFrame *frame;
-    FlacSubframe *sub;
-
-    frame = &ctx->frame;
-    sub = &frame->subframes[ch];
-
-    /* warm-up samples */
-    for(i=0; i<sub->order; i++) {
-        put_sbits(&ctx->pb, sub->obits, sub->residual[i]);
-    }
-
-    /* residual */
-    output_residual(ctx, ch);
-}
-
-static void output_subframe_lpc(FlacEncodeContext *ctx, int ch)
-{
-    int i, cbits;
-    FlacFrame *frame;
-    FlacSubframe *sub;
-
-    frame = &ctx->frame;
-    sub = &frame->subframes[ch];
-
-    /* warm-up samples */
-    for(i=0; i<sub->order; i++) {
-        put_sbits(&ctx->pb, sub->obits, sub->residual[i]);
-    }
-
-    /* LPC coefficients */
-    cbits = ctx->options.lpc_coeff_precision;
-    put_bits(&ctx->pb, 4, cbits-1);
-    put_sbits(&ctx->pb, 5, sub->shift);
-    for(i=0; i<sub->order; i++) {
-        put_sbits(&ctx->pb, cbits, sub->coefs[i]);
-    }
-
-    /* residual */
-    output_residual(ctx, ch);
-}
-
-static void output_subframes(FlacEncodeContext *s)
-{
-    FlacFrame *frame;
-    FlacSubframe *sub;
-    int ch;
-
-    frame = &s->frame;
-
-    for(ch=0; ch<s->channels; ch++) {
-        sub = &frame->subframes[ch];
-
-        /* subframe header */
-        put_bits(&s->pb, 1, 0);
-        put_bits(&s->pb, 6, sub->type_code);
-        put_bits(&s->pb, 1, 0); /* no wasted bits */
-
-        /* subframe */
-        if(sub->type == FLAC_SUBFRAME_CONSTANT) {
-            output_subframe_constant(s, ch);
-        } else if(sub->type == FLAC_SUBFRAME_VERBATIM) {
-            output_subframe_verbatim(s, ch);
-        } else if(sub->type == FLAC_SUBFRAME_FIXED) {
-            output_subframe_fixed(s, ch);
-        } else if(sub->type == FLAC_SUBFRAME_LPC) {
-            output_subframe_lpc(s, ch);
-        }
-    }
-}
-
-static void output_frame_footer(FlacEncodeContext *s)
-{
-    int crc;
-    flush_put_bits(&s->pb);
-    crc = bswap_16(av_crc(av_crc_get_table(AV_CRC_16_ANSI), 0,
-                          s->pb.buf, put_bits_count(&s->pb)>>3));
-    put_bits(&s->pb, 16, crc);
-    flush_put_bits(&s->pb);
-}
-
-static int flac_encode_frame(AVCodecContext *avctx, uint8_t *frame,
-                             int buf_size, void *data)
-{
-    int ch;
-    FlacEncodeContext *s;
-    int16_t *samples = data;
-    int out_bytes;
-
-    s = avctx->priv_data;
-
-    init_frame(s);
-
-    copy_samples(s, samples);
-
-    channel_decorrelation(s);
-
-    for(ch=0; ch<s->channels; ch++) {
-        encode_residual(s, ch);
-    }
-    init_put_bits(&s->pb, frame, buf_size);
-    output_frame_header(s);
-    output_subframes(s);
-    output_frame_footer(s);
-    out_bytes = put_bits_count(&s->pb) >> 3;
-
-    if(out_bytes > s->max_framesize || out_bytes >= buf_size) {
-        /* frame too large. use verbatim mode */
-        for(ch=0; ch<s->channels; ch++) {
-            encode_residual_v(s, ch);
-        }
-        init_put_bits(&s->pb, frame, buf_size);
-        output_frame_header(s);
-        output_subframes(s);
-        output_frame_footer(s);
-        out_bytes = put_bits_count(&s->pb) >> 3;
-
-        if(out_bytes > s->max_framesize || out_bytes >= buf_size) {
-            /* still too large. must be an error. */
-            av_log(avctx, AV_LOG_ERROR, "error encoding frame\n");
-            return -1;
-        }
-    }
-
-    s->frame_count++;
-    return out_bytes;
-}
-
-static av_cold int flac_encode_close(AVCodecContext *avctx)
-{
-    av_freep(&avctx->extradata);
-    avctx->extradata_size = 0;
-    av_freep(&avctx->coded_frame);
-    return 0;
-}
-
-AVCodec flac_encoder = {
-    "flac",
-    CODEC_TYPE_AUDIO,
-    CODEC_ID_FLAC,
-    sizeof(FlacEncodeContext),
-    flac_encode_init,
-    flac_encode_frame,
-    flac_encode_close,
-    NULL,
-    .capabilities = CODEC_CAP_SMALL_LAST_FRAME,
-    .sample_fmts = (enum SampleFormat[]){SAMPLE_FMT_S16,SAMPLE_FMT_NONE},
-    .long_name = NULL_IF_CONFIG_SMALL("FLAC (Free Lossless Audio Codec)"),
-};

Copied: trunk/libavcodec/lpc.h (from r14789, /trunk/libavcodec/flacenc.c)
==============================================================================
--- /trunk/libavcodec/flacenc.c	(original)
+++ trunk/libavcodec/lpc.h	Sat Aug 16 19:18:20 2008
@@ -1,5 +1,5 @@
 /**
- * FLAC audio encoder
+ * LPC utility code
  * Copyright (c) 2006  Justin Ruggles <jruggle at earthlink.net>
  *
  * This file is part of FFmpeg.
@@ -19,27 +19,10 @@
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
-#include "libavutil/crc.h"
-#include "libavutil/lls.h"
-#include "avcodec.h"
-#include "bitstream.h"
-#include "dsputil.h"
-#include "golomb.h"
-
-#define FLAC_MAX_CH  8
-#define FLAC_MIN_BLOCKSIZE  16
-#define FLAC_MAX_BLOCKSIZE  65535
-
-#define FLAC_SUBFRAME_CONSTANT  0
-#define FLAC_SUBFRAME_VERBATIM  1
-#define FLAC_SUBFRAME_FIXED     8
-#define FLAC_SUBFRAME_LPC      32
+#ifndef FFMPEG_LPC_H
+#define FFMPEG_LPC_H
 
-#define FLAC_CHMODE_NOT_STEREO      0
-#define FLAC_CHMODE_LEFT_RIGHT      1
-#define FLAC_CHMODE_LEFT_SIDE       8
-#define FLAC_CHMODE_RIGHT_SIDE      9
-#define FLAC_CHMODE_MID_SIDE       10
+#include <inttypes.h>
 
 #define ORDER_METHOD_EST     0
 #define ORDER_METHOD_2LEVEL  1
@@ -48,1444 +31,16 @@
 #define ORDER_METHOD_SEARCH  4
 #define ORDER_METHOD_LOG     5
 
-#define FLAC_STREAMINFO_SIZE  34
-
 #define MIN_LPC_ORDER       1
 #define MAX_LPC_ORDER      32
-#define MAX_FIXED_ORDER     4
-#define MAX_PARTITION_ORDER 8
-#define MAX_PARTITIONS     (1 << MAX_PARTITION_ORDER)
-#define MAX_LPC_PRECISION  15
-#define MAX_LPC_SHIFT      15
-#define MAX_RICE_PARAM     14
-
-typedef struct CompressionOptions {
-    int compression_level;
-    int block_time_ms;
-    int use_lpc;
-    int lpc_coeff_precision;
-    int min_prediction_order;
-    int max_prediction_order;
-    int prediction_order_method;
-    int min_partition_order;
-    int max_partition_order;
-} CompressionOptions;
-
-typedef struct RiceContext {
-    int porder;
-    int params[MAX_PARTITIONS];
-} RiceContext;
-
-typedef struct FlacSubframe {
-    int type;
-    int type_code;
-    int obits;
-    int order;
-    int32_t coefs[MAX_LPC_ORDER];
-    int shift;
-    RiceContext rc;
-    int32_t samples[FLAC_MAX_BLOCKSIZE];
-    int32_t residual[FLAC_MAX_BLOCKSIZE+1];
-} FlacSubframe;
-
-typedef struct FlacFrame {
-    FlacSubframe subframes[FLAC_MAX_CH];
-    int blocksize;
-    int bs_code[2];
-    uint8_t crc8;
-    int ch_mode;
-} FlacFrame;
-
-typedef struct FlacEncodeContext {
-    PutBitContext pb;
-    int channels;
-    int ch_code;
-    int samplerate;
-    int sr_code[2];
-    int max_framesize;
-    uint32_t frame_count;
-    FlacFrame frame;
-    CompressionOptions options;
-    AVCodecContext *avctx;
-    DSPContext dsp;
-} FlacEncodeContext;
-
-static const int flac_samplerates[16] = {
-    0, 0, 0, 0,
-    8000, 16000, 22050, 24000, 32000, 44100, 48000, 96000,
-    0, 0, 0, 0
-};
-
-static const int flac_blocksizes[16] = {
-    0,
-    192,
-    576, 1152, 2304, 4608,
-    0, 0,
-    256, 512, 1024, 2048, 4096, 8192, 16384, 32768
-};
-
-/**
- * Writes streaminfo metadata block to byte array
- */
-static void write_streaminfo(FlacEncodeContext *s, uint8_t *header)
-{
-    PutBitContext pb;
-
-    memset(header, 0, FLAC_STREAMINFO_SIZE);
-    init_put_bits(&pb, header, FLAC_STREAMINFO_SIZE);
-
-    /* streaminfo metadata block */
-    put_bits(&pb, 16, s->avctx->frame_size);
-    put_bits(&pb, 16, s->avctx->frame_size);
-    put_bits(&pb, 24, 0);
-    put_bits(&pb, 24, s->max_framesize);
-    put_bits(&pb, 20, s->samplerate);
-    put_bits(&pb, 3, s->channels-1);
-    put_bits(&pb, 5, 15);       /* bits per sample - 1 */
-    flush_put_bits(&pb);
-    /* total samples = 0 */
-    /* MD5 signature = 0 */
-}
-
-/**
- * Sets blocksize based on samplerate
- * Chooses the closest predefined blocksize >= BLOCK_TIME_MS milliseconds
- */
-static int select_blocksize(int samplerate, int block_time_ms)
-{
-    int i;
-    int target;
-    int blocksize;
-
-    assert(samplerate > 0);
-    blocksize = flac_blocksizes[1];
-    target = (samplerate * block_time_ms) / 1000;
-    for(i=0; i<16; i++) {
-        if(target >= flac_blocksizes[i] && flac_blocksizes[i] > blocksize) {
-            blocksize = flac_blocksizes[i];
-        }
-    }
-    return blocksize;
-}
-
-static av_cold int flac_encode_init(AVCodecContext *avctx)
-{
-    int freq = avctx->sample_rate;
-    int channels = avctx->channels;
-    FlacEncodeContext *s = avctx->priv_data;
-    int i, level;
-    uint8_t *streaminfo;
-
-    s->avctx = avctx;
-
-    dsputil_init(&s->dsp, avctx);
-
-    if(avctx->sample_fmt != SAMPLE_FMT_S16) {
-        return -1;
-    }
-
-    if(channels < 1 || channels > FLAC_MAX_CH) {
-        return -1;
-    }
-    s->channels = channels;
-    s->ch_code = s->channels-1;
-
-    /* find samplerate in table */
-    if(freq < 1)
-        return -1;
-    for(i=4; i<12; i++) {
-        if(freq == flac_samplerates[i]) {
-            s->samplerate = flac_samplerates[i];
-            s->sr_code[0] = i;
-            s->sr_code[1] = 0;
-            break;
-        }
-    }
-    /* if not in table, samplerate is non-standard */
-    if(i == 12) {
-        if(freq % 1000 == 0 && freq < 255000) {
-            s->sr_code[0] = 12;
-            s->sr_code[1] = freq / 1000;
-        } else if(freq % 10 == 0 && freq < 655350) {
-            s->sr_code[0] = 14;
-            s->sr_code[1] = freq / 10;
-        } else if(freq < 65535) {
-            s->sr_code[0] = 13;
-            s->sr_code[1] = freq;
-        } else {
-            return -1;
-        }
-        s->samplerate = freq;
-    }
-
-    /* set compression option defaults based on avctx->compression_level */
-    if(avctx->compression_level < 0) {
-        s->options.compression_level = 5;
-    } else {
-        s->options.compression_level = avctx->compression_level;
-    }
-    av_log(avctx, AV_LOG_DEBUG, " compression: %d\n", s->options.compression_level);
-
-    level= s->options.compression_level;
-    if(level > 12) {
-        av_log(avctx, AV_LOG_ERROR, "invalid compression level: %d\n",
-               s->options.compression_level);
-        return -1;
-    }
-
-    s->options.block_time_ms       = ((int[]){ 27, 27, 27,105,105,105,105,105,105,105,105,105,105})[level];
-    s->options.use_lpc             = ((int[]){  0,  0,  0,  1,  1,  1,  1,  1,  1,  1,  1,  1,  1})[level];
-    s->options.min_prediction_order= ((int[]){  2,  0,  0,  1,  1,  1,  1,  1,  1,  1,  1,  1,  1})[level];
-    s->options.max_prediction_order= ((int[]){  3,  4,  4,  6,  8,  8,  8,  8, 12, 12, 12, 32, 32})[level];
-    s->options.prediction_order_method = ((int[]){ ORDER_METHOD_EST,    ORDER_METHOD_EST,    ORDER_METHOD_EST,
-                                                   ORDER_METHOD_EST,    ORDER_METHOD_EST,    ORDER_METHOD_EST,
-                                                   ORDER_METHOD_4LEVEL, ORDER_METHOD_LOG,    ORDER_METHOD_4LEVEL,
-                                                   ORDER_METHOD_LOG,    ORDER_METHOD_SEARCH, ORDER_METHOD_LOG,
-                                                   ORDER_METHOD_SEARCH})[level];
-    s->options.min_partition_order = ((int[]){  2,  2,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0})[level];
-    s->options.max_partition_order = ((int[]){  2,  2,  3,  3,  3,  8,  8,  8,  8,  8,  8,  8,  8})[level];
-
-    /* set compression option overrides from AVCodecContext */
-    if(avctx->use_lpc >= 0) {
-        s->options.use_lpc = av_clip(avctx->use_lpc, 0, 11);
-    }
-    if(s->options.use_lpc == 1)
-        av_log(avctx, AV_LOG_DEBUG, " use lpc: Levinson-Durbin recursion with Welch window\n");
-    else if(s->options.use_lpc > 1)
-        av_log(avctx, AV_LOG_DEBUG, " use lpc: Cholesky factorization\n");
-
-    if(avctx->min_prediction_order >= 0) {
-        if(s->options.use_lpc) {
-            if(avctx->min_prediction_order < MIN_LPC_ORDER ||
-                    avctx->min_prediction_order > MAX_LPC_ORDER) {
-                av_log(avctx, AV_LOG_ERROR, "invalid min prediction order: %d\n",
-                       avctx->min_prediction_order);
-                return -1;
-            }
-        } else {
-            if(avctx->min_prediction_order > MAX_FIXED_ORDER) {
-                av_log(avctx, AV_LOG_ERROR, "invalid min prediction order: %d\n",
-                       avctx->min_prediction_order);
-                return -1;
-            }
-        }
-        s->options.min_prediction_order = avctx->min_prediction_order;
-    }
-    if(avctx->max_prediction_order >= 0) {
-        if(s->options.use_lpc) {
-            if(avctx->max_prediction_order < MIN_LPC_ORDER ||
-                    avctx->max_prediction_order > MAX_LPC_ORDER) {
-                av_log(avctx, AV_LOG_ERROR, "invalid max prediction order: %d\n",
-                       avctx->max_prediction_order);
-                return -1;
-            }
-        } else {
-            if(avctx->max_prediction_order > MAX_FIXED_ORDER) {
-                av_log(avctx, AV_LOG_ERROR, "invalid max prediction order: %d\n",
-                       avctx->max_prediction_order);
-                return -1;
-            }
-        }
-        s->options.max_prediction_order = avctx->max_prediction_order;
-    }
-    if(s->options.max_prediction_order < s->options.min_prediction_order) {
-        av_log(avctx, AV_LOG_ERROR, "invalid prediction orders: min=%d max=%d\n",
-               s->options.min_prediction_order, s->options.max_prediction_order);
-        return -1;
-    }
-    av_log(avctx, AV_LOG_DEBUG, " prediction order: %d, %d\n",
-           s->options.min_prediction_order, s->options.max_prediction_order);
-
-    if(avctx->prediction_order_method >= 0) {
-        if(avctx->prediction_order_method > ORDER_METHOD_LOG) {
-            av_log(avctx, AV_LOG_ERROR, "invalid prediction order method: %d\n",
-                   avctx->prediction_order_method);
-            return -1;
-        }
-        s->options.prediction_order_method = avctx->prediction_order_method;
-    }
-    switch(s->options.prediction_order_method) {
-        case ORDER_METHOD_EST:    av_log(avctx, AV_LOG_DEBUG, " order method: %s\n",
-                                         "estimate"); break;
-        case ORDER_METHOD_2LEVEL: av_log(avctx, AV_LOG_DEBUG, " order method: %s\n",
-                                         "2-level"); break;
-        case ORDER_METHOD_4LEVEL: av_log(avctx, AV_LOG_DEBUG, " order method: %s\n",
-                                         "4-level"); break;
-        case ORDER_METHOD_8LEVEL: av_log(avctx, AV_LOG_DEBUG, " order method: %s\n",
-                                         "8-level"); break;
-        case ORDER_METHOD_SEARCH: av_log(avctx, AV_LOG_DEBUG, " order method: %s\n",
-                                         "full search"); break;
-        case ORDER_METHOD_LOG:    av_log(avctx, AV_LOG_DEBUG, " order method: %s\n",
-                                         "log search"); break;
-    }
-
-    if(avctx->min_partition_order >= 0) {
-        if(avctx->min_partition_order > MAX_PARTITION_ORDER) {
-            av_log(avctx, AV_LOG_ERROR, "invalid min partition order: %d\n",
-                   avctx->min_partition_order);
-            return -1;
-        }
-        s->options.min_partition_order = avctx->min_partition_order;
-    }
-    if(avctx->max_partition_order >= 0) {
-        if(avctx->max_partition_order > MAX_PARTITION_ORDER) {
-            av_log(avctx, AV_LOG_ERROR, "invalid max partition order: %d\n",
-                   avctx->max_partition_order);
-            return -1;
-        }
-        s->options.max_partition_order = avctx->max_partition_order;
-    }
-    if(s->options.max_partition_order < s->options.min_partition_order) {
-        av_log(avctx, AV_LOG_ERROR, "invalid partition orders: min=%d max=%d\n",
-               s->options.min_partition_order, s->options.max_partition_order);
-        return -1;
-    }
-    av_log(avctx, AV_LOG_DEBUG, " partition order: %d, %d\n",
-           s->options.min_partition_order, s->options.max_partition_order);
-
-    if(avctx->frame_size > 0) {
-        if(avctx->frame_size < FLAC_MIN_BLOCKSIZE ||
-                avctx->frame_size > FLAC_MAX_BLOCKSIZE) {
-            av_log(avctx, AV_LOG_ERROR, "invalid block size: %d\n",
-                   avctx->frame_size);
-            return -1;
-        }
-    } else {
-        s->avctx->frame_size = select_blocksize(s->samplerate, s->options.block_time_ms);
-    }
-    av_log(avctx, AV_LOG_DEBUG, " block size: %d\n", s->avctx->frame_size);
-
-    /* set LPC precision */
-    if(avctx->lpc_coeff_precision > 0) {
-        if(avctx->lpc_coeff_precision > MAX_LPC_PRECISION) {
-            av_log(avctx, AV_LOG_ERROR, "invalid lpc coeff precision: %d\n",
-                   avctx->lpc_coeff_precision);
-            return -1;
-        }
-        s->options.lpc_coeff_precision = avctx->lpc_coeff_precision;
-    } else {
-        /* default LPC precision */
-        s->options.lpc_coeff_precision = 15;
-    }
-    av_log(avctx, AV_LOG_DEBUG, " lpc precision: %d\n",
-           s->options.lpc_coeff_precision);
-
-    /* set maximum encoded frame size in verbatim mode */
-    if(s->channels == 2) {
-        s->max_framesize = 14 + ((s->avctx->frame_size * 33 + 7) >> 3);
-    } else {
-        s->max_framesize = 14 + (s->avctx->frame_size * s->channels * 2);
-    }
-
-    streaminfo = av_malloc(FLAC_STREAMINFO_SIZE);
-    write_streaminfo(s, streaminfo);
-    avctx->extradata = streaminfo;
-    avctx->extradata_size = FLAC_STREAMINFO_SIZE;
-
-    s->frame_count = 0;
-
-    avctx->coded_frame = avcodec_alloc_frame();
-    avctx->coded_frame->key_frame = 1;
-
-    return 0;
-}
-
-static void init_frame(FlacEncodeContext *s)
-{
-    int i, ch;
-    FlacFrame *frame;
-
-    frame = &s->frame;
-
-    for(i=0; i<16; i++) {
-        if(s->avctx->frame_size == flac_blocksizes[i]) {
-            frame->blocksize = flac_blocksizes[i];
-            frame->bs_code[0] = i;
-            frame->bs_code[1] = 0;
-            break;
-        }
-    }
-    if(i == 16) {
-        frame->blocksize = s->avctx->frame_size;
-        if(frame->blocksize <= 256) {
-            frame->bs_code[0] = 6;
-            frame->bs_code[1] = frame->blocksize-1;
-        } else {
-            frame->bs_code[0] = 7;
-            frame->bs_code[1] = frame->blocksize-1;
-        }
-    }
-
-    for(ch=0; ch<s->channels; ch++) {
-        frame->subframes[ch].obits = 16;
-    }
-}
-
-/**
- * Copy channel-interleaved input samples into separate subframes
- */
-static void copy_samples(FlacEncodeContext *s, int16_t *samples)
-{
-    int i, j, ch;
-    FlacFrame *frame;
-
-    frame = &s->frame;
-    for(i=0,j=0; i<frame->blocksize; i++) {
-        for(ch=0; ch<s->channels; ch++,j++) {
-            frame->subframes[ch].samples[i] = samples[j];
-        }
-    }
-}
 
 
-#define rice_encode_count(sum, n, k) (((n)*((k)+1))+((sum-(n>>1))>>(k)))
-
-/**
- * Solve for d/dk(rice_encode_count) = n-((sum-(n>>1))>>(k+1)) = 0
- */
-static int find_optimal_param(uint32_t sum, int n)
-{
-    int k;
-    uint32_t sum2;
-
-    if(sum <= n>>1)
-        return 0;
-    sum2 = sum-(n>>1);
-    k = av_log2(n<256 ? FASTDIV(sum2,n) : sum2/n);
-    return FFMIN(k, MAX_RICE_PARAM);
-}
-
-static uint32_t calc_optimal_rice_params(RiceContext *rc, int porder,
-                                         uint32_t *sums, int n, int pred_order)
-{
-    int i;
-    int k, cnt, part;
-    uint32_t all_bits;
-
-    part = (1 << porder);
-    all_bits = 4 * part;
-
-    cnt = (n >> porder) - pred_order;
-    for(i=0; i<part; i++) {
-        k = find_optimal_param(sums[i], cnt);
-        rc->params[i] = k;
-        all_bits += rice_encode_count(sums[i], cnt, k);
-        cnt = n >> porder;
-    }
-
-    rc->porder = porder;
-
-    return all_bits;
-}
-
-static void calc_sums(int pmin, int pmax, uint32_t *data, int n, int pred_order,
-                      uint32_t sums[][MAX_PARTITIONS])
-{
-    int i, j;
-    int parts;
-    uint32_t *res, *res_end;
-
-    /* sums for highest level */
-    parts = (1 << pmax);
-    res = &data[pred_order];
-    res_end = &data[n >> pmax];
-    for(i=0; i<parts; i++) {
-        uint32_t sum = 0;
-        while(res < res_end){
-            sum += *(res++);
-        }
-        sums[pmax][i] = sum;
-        res_end+= n >> pmax;
-    }
-    /* sums for lower levels */
-    for(i=pmax-1; i>=pmin; i--) {
-        parts = (1 << i);
-        for(j=0; j<parts; j++) {
-            sums[i][j] = sums[i+1][2*j] + sums[i+1][2*j+1];
-        }
-    }
-}
-
-static uint32_t calc_rice_params(RiceContext *rc, int pmin, int pmax,
-                                 int32_t *data, int n, int pred_order)
-{
-    int i;
-    uint32_t bits[MAX_PARTITION_ORDER+1];
-    int opt_porder;
-    RiceContext tmp_rc;
-    uint32_t *udata;
-    uint32_t sums[MAX_PARTITION_ORDER+1][MAX_PARTITIONS];
-
-    assert(pmin >= 0 && pmin <= MAX_PARTITION_ORDER);
-    assert(pmax >= 0 && pmax <= MAX_PARTITION_ORDER);
-    assert(pmin <= pmax);
-
-    udata = av_malloc(n * sizeof(uint32_t));
-    for(i=0; i<n; i++) {
-        udata[i] = (2*data[i]) ^ (data[i]>>31);
-    }
-
-    calc_sums(pmin, pmax, udata, n, pred_order, sums);
-
-    opt_porder = pmin;
-    bits[pmin] = UINT32_MAX;
-    for(i=pmin; i<=pmax; i++) {
-        bits[i] = calc_optimal_rice_params(&tmp_rc, i, sums[i], n, pred_order);
-        if(bits[i] <= bits[opt_porder]) {
-            opt_porder = i;
-            *rc= tmp_rc;
-        }
-    }
-
-    av_freep(&udata);
-    return bits[opt_porder];
-}
-
-static int get_max_p_order(int max_porder, int n, int order)
-{
-    int porder = FFMIN(max_porder, av_log2(n^(n-1)));
-    if(order > 0)
-        porder = FFMIN(porder, av_log2(n/order));
-    return porder;
-}
-
-static uint32_t calc_rice_params_fixed(RiceContext *rc, int pmin, int pmax,
-                                       int32_t *data, int n, int pred_order,
-                                       int bps)
-{
-    uint32_t bits;
-    pmin = get_max_p_order(pmin, n, pred_order);
-    pmax = get_max_p_order(pmax, n, pred_order);
-    bits = pred_order*bps + 6;
-    bits += calc_rice_params(rc, pmin, pmax, data, n, pred_order);
-    return bits;
-}
-
-static uint32_t calc_rice_params_lpc(RiceContext *rc, int pmin, int pmax,
-                                     int32_t *data, int n, int pred_order,
-                                     int bps, int precision)
-{
-    uint32_t bits;
-    pmin = get_max_p_order(pmin, n, pred_order);
-    pmax = get_max_p_order(pmax, n, pred_order);
-    bits = pred_order*bps + 4 + 5 + pred_order*precision + 6;
-    bits += calc_rice_params(rc, pmin, pmax, data, n, pred_order);
-    return bits;
-}
-
-/**
- * Apply Welch window function to audio block
- */
-static void apply_welch_window(const int32_t *data, int len, double *w_data)
-{
-    int i, n2;
-    double w;
-    double c;
-
-    assert(!(len&1)); //the optimization in r11881 does not support odd len
-                      //if someone wants odd len extend the change in r11881
-
-    n2 = (len >> 1);
-    c = 2.0 / (len - 1.0);
-
-    w_data+=n2;
-      data+=n2;
-    for(i=0; i<n2; i++) {
-        w = c - n2 + i;
-        w = 1.0 - (w * w);
-        w_data[-i-1] = data[-i-1] * w;
-        w_data[+i  ] = data[+i  ] * w;
-    }
-}
-
-/**
- * Calculates autocorrelation data from audio samples
- * A Welch window function is applied before calculation.
- */
-void ff_flac_compute_autocorr(const int32_t *data, int len, int lag,
-                              double *autoc)
-{
-    int i, j;
-    double tmp[len + lag + 1];
-    double *data1= tmp + lag;
-
-    apply_welch_window(data, len, data1);
-
-    for(j=0; j<lag; j++)
-        data1[j-lag]= 0.0;
-    data1[len] = 0.0;
-
-    for(j=0; j<lag; j+=2){
-        double sum0 = 1.0, sum1 = 1.0;
-        for(i=0; i<len; i++){
-            sum0 += data1[i] * data1[i-j];
-            sum1 += data1[i] * data1[i-j-1];
-        }
-        autoc[j  ] = sum0;
-        autoc[j+1] = sum1;
-    }
-
-    if(j==lag){
-        double sum = 1.0;
-        for(i=0; i<len; i+=2){
-            sum += data1[i  ] * data1[i-j  ]
-                 + data1[i+1] * data1[i-j+1];
-        }
-        autoc[j] = sum;
-    }
-}
-
-/**
- * Levinson-Durbin recursion.
- * Produces LPC coefficients from autocorrelation data.
- */
-static void compute_lpc_coefs(const double *autoc, int max_order,
-                              double lpc[][MAX_LPC_ORDER], double *ref)
-{
-   int i, j, i2;
-   double r, err, tmp;
-   double lpc_tmp[MAX_LPC_ORDER];
-
-   for(i=0; i<max_order; i++) lpc_tmp[i] = 0;
-   err = autoc[0];
-
-   for(i=0; i<max_order; i++) {
-      r = -autoc[i+1];
-      for(j=0; j<i; j++) {
-          r -= lpc_tmp[j] * autoc[i-j];
-      }
-      r /= err;
-      ref[i] = fabs(r);
-
-      err *= 1.0 - (r * r);
-
-      i2 = (i >> 1);
-      lpc_tmp[i] = r;
-      for(j=0; j<i2; j++) {
-         tmp = lpc_tmp[j];
-         lpc_tmp[j] += r * lpc_tmp[i-1-j];
-         lpc_tmp[i-1-j] += r * tmp;
-      }
-      if(i & 1) {
-          lpc_tmp[j] += lpc_tmp[j] * r;
-      }
-
-      for(j=0; j<=i; j++) {
-          lpc[i][j] = -lpc_tmp[j];
-      }
-   }
-}
-
-/**
- * Quantize LPC coefficients
- */
-static void quantize_lpc_coefs(double *lpc_in, int order, int precision,
-                               int32_t *lpc_out, int *shift, int max_shift, int zero_shift)
-{
-    int i;
-    double cmax, error;
-    int32_t qmax;
-    int sh;
-
-    /* define maximum levels */
-    qmax = (1 << (precision - 1)) - 1;
-
-    /* find maximum coefficient value */
-    cmax = 0.0;
-    for(i=0; i<order; i++) {
-        cmax= FFMAX(cmax, fabs(lpc_in[i]));
-    }
-
-    /* if maximum value quantizes to zero, return all zeros */
-    if(cmax * (1 << max_shift) < 1.0) {
-        *shift = zero_shift;
-        memset(lpc_out, 0, sizeof(int32_t) * order);
-        return;
-    }
-
-    /* calculate level shift which scales max coeff to available bits */
-    sh = max_shift;
-    while((cmax * (1 << sh) > qmax) && (sh > 0)) {
-        sh--;
-    }
-
-    /* since negative shift values are unsupported in decoder, scale down
-       coefficients instead */
-    if(sh == 0 && cmax > qmax) {
-        double scale = ((double)qmax) / cmax;
-        for(i=0; i<order; i++) {
-            lpc_in[i] *= scale;
-        }
-    }
-
-    /* output quantized coefficients and level shift */
-    error=0;
-    for(i=0; i<order; i++) {
-        error += lpc_in[i] * (1 << sh);
-        lpc_out[i] = av_clip(lrintf(error), -qmax, qmax);
-        error -= lpc_out[i];
-    }
-    *shift = sh;
-}
-
-static int estimate_best_order(double *ref, int max_order)
-{
-    int i, est;
-
-    est = 1;
-    for(i=max_order-1; i>=0; i--) {
-        if(ref[i] > 0.10) {
-            est = i+1;
-            break;
-        }
-    }
-    return est;
-}
-
 /**
  * Calculate LPC coefficients for multiple orders
  */
-static int lpc_calc_coefs(DSPContext *s,
+int ff_lpc_calc_coefs(DSPContext *s,
                           const int32_t *samples, int blocksize, int max_order,
                           int precision, int32_t coefs[][MAX_LPC_ORDER],
-                          int *shift, int use_lpc, int omethod, int max_shift, int zero_shift)
-{
-    double autoc[MAX_LPC_ORDER+1];
-    double ref[MAX_LPC_ORDER];
-    double lpc[MAX_LPC_ORDER][MAX_LPC_ORDER];
-    int i, j, pass;
-    int opt_order;
-
-    assert(max_order >= MIN_LPC_ORDER && max_order <= MAX_LPC_ORDER);
-
-    if(use_lpc == 1){
-        s->flac_compute_autocorr(samples, blocksize, max_order, autoc);
-
-        compute_lpc_coefs(autoc, max_order, lpc, ref);
-    }else{
-        LLSModel m[2];
-        double var[MAX_LPC_ORDER+1], weight;
-
-        for(pass=0; pass<use_lpc-1; pass++){
-            av_init_lls(&m[pass&1], max_order);
-
-            weight=0;
-            for(i=max_order; i<blocksize; i++){
-                for(j=0; j<=max_order; j++)
-                    var[j]= samples[i-j];
-
-                if(pass){
-                    double eval, inv, rinv;
-                    eval= av_evaluate_lls(&m[(pass-1)&1], var+1, max_order-1);
-                    eval= (512>>pass) + fabs(eval - var[0]);
-                    inv = 1/eval;
-                    rinv = sqrt(inv);
-                    for(j=0; j<=max_order; j++)
-                        var[j] *= rinv;
-                    weight += inv;
-                }else
-                    weight++;
-
-                av_update_lls(&m[pass&1], var, 1.0);
-            }
-            av_solve_lls(&m[pass&1], 0.001, 0);
-        }
-
-        for(i=0; i<max_order; i++){
-            for(j=0; j<max_order; j++)
-                lpc[i][j]= m[(pass-1)&1].coeff[i][j];
-            ref[i]= sqrt(m[(pass-1)&1].variance[i] / weight) * (blocksize - max_order) / 4000;
-        }
-        for(i=max_order-1; i>0; i--)
-            ref[i] = ref[i-1] - ref[i];
-    }
-    opt_order = max_order;
-
-    if(omethod == ORDER_METHOD_EST) {
-        opt_order = estimate_best_order(ref, max_order);
-        i = opt_order-1;
-        quantize_lpc_coefs(lpc[i], i+1, precision, coefs[i], &shift[i], max_shift, zero_shift);
-    } else {
-        for(i=0; i<max_order; i++) {
-            quantize_lpc_coefs(lpc[i], i+1, precision, coefs[i], &shift[i], max_shift, zero_shift);
-        }
-    }
-
-    return opt_order;
-}
-
-
-static void encode_residual_verbatim(int32_t *res, int32_t *smp, int n)
-{
-    assert(n > 0);
-    memcpy(res, smp, n * sizeof(int32_t));
-}
-
-static void encode_residual_fixed(int32_t *res, const int32_t *smp, int n,
-                                  int order)
-{
-    int i;
-
-    for(i=0; i<order; i++) {
-        res[i] = smp[i];
-    }
-
-    if(order==0){
-        for(i=order; i<n; i++)
-            res[i]= smp[i];
-    }else if(order==1){
-        for(i=order; i<n; i++)
-            res[i]= smp[i] - smp[i-1];
-    }else if(order==2){
-        int a = smp[order-1] - smp[order-2];
-        for(i=order; i<n; i+=2) {
-            int b = smp[i] - smp[i-1];
-            res[i]= b - a;
-            a = smp[i+1] - smp[i];
-            res[i+1]= a - b;
-        }
-    }else if(order==3){
-        int a = smp[order-1] - smp[order-2];
-        int c = smp[order-1] - 2*smp[order-2] + smp[order-3];
-        for(i=order; i<n; i+=2) {
-            int b = smp[i] - smp[i-1];
-            int d = b - a;
-            res[i]= d - c;
-            a = smp[i+1] - smp[i];
-            c = a - b;
-            res[i+1]= c - d;
-        }
-    }else{
-        int a = smp[order-1] - smp[order-2];
-        int c = smp[order-1] - 2*smp[order-2] + smp[order-3];
-        int e = smp[order-1] - 3*smp[order-2] + 3*smp[order-3] - smp[order-4];
-        for(i=order; i<n; i+=2) {
-            int b = smp[i] - smp[i-1];
-            int d = b - a;
-            int f = d - c;
-            res[i]= f - e;
-            a = smp[i+1] - smp[i];
-            c = a - b;
-            e = c - d;
-            res[i+1]= e - f;
-        }
-    }
-}
-
-#define LPC1(x) {\
-    int c = coefs[(x)-1];\
-    p0 += c*s;\
-    s = smp[i-(x)+1];\
-    p1 += c*s;\
-}
-
-static av_always_inline void encode_residual_lpc_unrolled(
-    int32_t *res, const int32_t *smp, int n,
-    int order, const int32_t *coefs, int shift, int big)
-{
-    int i;
-    for(i=order; i<n; i+=2) {
-        int s = smp[i-order];
-        int p0 = 0, p1 = 0;
-        if(big) {
-            switch(order) {
-                case 32: LPC1(32)
-                case 31: LPC1(31)
-                case 30: LPC1(30)
-                case 29: LPC1(29)
-                case 28: LPC1(28)
-                case 27: LPC1(27)
-                case 26: LPC1(26)
-                case 25: LPC1(25)
-                case 24: LPC1(24)
-                case 23: LPC1(23)
-                case 22: LPC1(22)
-                case 21: LPC1(21)
-                case 20: LPC1(20)
-                case 19: LPC1(19)
-                case 18: LPC1(18)
-                case 17: LPC1(17)
-                case 16: LPC1(16)
-                case 15: LPC1(15)
-                case 14: LPC1(14)
-                case 13: LPC1(13)
-                case 12: LPC1(12)
-                case 11: LPC1(11)
-                case 10: LPC1(10)
-                case  9: LPC1( 9)
-                         LPC1( 8)
-                         LPC1( 7)
-                         LPC1( 6)
-                         LPC1( 5)
-                         LPC1( 4)
-                         LPC1( 3)
-                         LPC1( 2)
-                         LPC1( 1)
-            }
-        } else {
-            switch(order) {
-                case  8: LPC1( 8)
-                case  7: LPC1( 7)
-                case  6: LPC1( 6)
-                case  5: LPC1( 5)
-                case  4: LPC1( 4)
-                case  3: LPC1( 3)
-                case  2: LPC1( 2)
-                case  1: LPC1( 1)
-            }
-        }
-        res[i  ] = smp[i  ] - (p0 >> shift);
-        res[i+1] = smp[i+1] - (p1 >> shift);
-    }
-}
-
-static void encode_residual_lpc(int32_t *res, const int32_t *smp, int n,
-                                int order, const int32_t *coefs, int shift)
-{
-    int i;
-    for(i=0; i<order; i++) {
-        res[i] = smp[i];
-    }
-#ifdef CONFIG_SMALL
-    for(i=order; i<n; i+=2) {
-        int j;
-        int s = smp[i];
-        int p0 = 0, p1 = 0;
-        for(j=0; j<order; j++) {
-            int c = coefs[j];
-            p1 += c*s;
-            s = smp[i-j-1];
-            p0 += c*s;
-        }
-        res[i  ] = smp[i  ] - (p0 >> shift);
-        res[i+1] = smp[i+1] - (p1 >> shift);
-    }
-#else
-    switch(order) {
-        case  1: encode_residual_lpc_unrolled(res, smp, n, 1, coefs, shift, 0); break;
-        case  2: encode_residual_lpc_unrolled(res, smp, n, 2, coefs, shift, 0); break;
-        case  3: encode_residual_lpc_unrolled(res, smp, n, 3, coefs, shift, 0); break;
-        case  4: encode_residual_lpc_unrolled(res, smp, n, 4, coefs, shift, 0); break;
-        case  5: encode_residual_lpc_unrolled(res, smp, n, 5, coefs, shift, 0); break;
-        case  6: encode_residual_lpc_unrolled(res, smp, n, 6, coefs, shift, 0); break;
-        case  7: encode_residual_lpc_unrolled(res, smp, n, 7, coefs, shift, 0); break;
-        case  8: encode_residual_lpc_unrolled(res, smp, n, 8, coefs, shift, 0); break;
-        default: encode_residual_lpc_unrolled(res, smp, n, order, coefs, shift, 1); break;
-    }
-#endif
-}
-
-static int encode_residual(FlacEncodeContext *ctx, int ch)
-{
-    int i, n;
-    int min_order, max_order, opt_order, precision, omethod;
-    int min_porder, max_porder;
-    FlacFrame *frame;
-    FlacSubframe *sub;
-    int32_t coefs[MAX_LPC_ORDER][MAX_LPC_ORDER];
-    int shift[MAX_LPC_ORDER];
-    int32_t *res, *smp;
-
-    frame = &ctx->frame;
-    sub = &frame->subframes[ch];
-    res = sub->residual;
-    smp = sub->samples;
-    n = frame->blocksize;
-
-    /* CONSTANT */
-    for(i=1; i<n; i++) {
-        if(smp[i] != smp[0]) break;
-    }
-    if(i == n) {
-        sub->type = sub->type_code = FLAC_SUBFRAME_CONSTANT;
-        res[0] = smp[0];
-        return sub->obits;
-    }
-
-    /* VERBATIM */
-    if(n < 5) {
-        sub->type = sub->type_code = FLAC_SUBFRAME_VERBATIM;
-        encode_residual_verbatim(res, smp, n);
-        return sub->obits * n;
-    }
-
-    min_order = ctx->options.min_prediction_order;
-    max_order = ctx->options.max_prediction_order;
-    min_porder = ctx->options.min_partition_order;
-    max_porder = ctx->options.max_partition_order;
-    precision = ctx->options.lpc_coeff_precision;
-    omethod = ctx->options.prediction_order_method;
-
-    /* FIXED */
-    if(!ctx->options.use_lpc || max_order == 0 || (n <= max_order)) {
-        uint32_t bits[MAX_FIXED_ORDER+1];
-        if(max_order > MAX_FIXED_ORDER) max_order = MAX_FIXED_ORDER;
-        opt_order = 0;
-        bits[0] = UINT32_MAX;
-        for(i=min_order; i<=max_order; i++) {
-            encode_residual_fixed(res, smp, n, i);
-            bits[i] = calc_rice_params_fixed(&sub->rc, min_porder, max_porder, res,
-                                             n, i, sub->obits);
-            if(bits[i] < bits[opt_order]) {
-                opt_order = i;
-            }
-        }
-        sub->order = opt_order;
-        sub->type = FLAC_SUBFRAME_FIXED;
-        sub->type_code = sub->type | sub->order;
-        if(sub->order != max_order) {
-            encode_residual_fixed(res, smp, n, sub->order);
-            return calc_rice_params_fixed(&sub->rc, min_porder, max_porder, res, n,
-                                          sub->order, sub->obits);
-        }
-        return bits[sub->order];
-    }
-
-    /* LPC */
-    opt_order = lpc_calc_coefs(&ctx->dsp, smp, n, max_order, precision, coefs,
-                               shift, ctx->options.use_lpc, omethod, MAX_LPC_SHIFT, 0);
-
-    if(omethod == ORDER_METHOD_2LEVEL ||
-       omethod == ORDER_METHOD_4LEVEL ||
-       omethod == ORDER_METHOD_8LEVEL) {
-        int levels = 1 << omethod;
-        uint32_t bits[levels];
-        int order;
-        int opt_index = levels-1;
-        opt_order = max_order-1;
-        bits[opt_index] = UINT32_MAX;
-        for(i=levels-1; i>=0; i--) {
-            order = min_order + (((max_order-min_order+1) * (i+1)) / levels)-1;
-            if(order < 0) order = 0;
-            encode_residual_lpc(res, smp, n, order+1, coefs[order], shift[order]);
-            bits[i] = calc_rice_params_lpc(&sub->rc, min_porder, max_porder,
-                                           res, n, order+1, sub->obits, precision);
-            if(bits[i] < bits[opt_index]) {
-                opt_index = i;
-                opt_order = order;
-            }
-        }
-        opt_order++;
-    } else if(omethod == ORDER_METHOD_SEARCH) {
-        // brute-force optimal order search
-        uint32_t bits[MAX_LPC_ORDER];
-        opt_order = 0;
-        bits[0] = UINT32_MAX;
-        for(i=min_order-1; i<max_order; i++) {
-            encode_residual_lpc(res, smp, n, i+1, coefs[i], shift[i]);
-            bits[i] = calc_rice_params_lpc(&sub->rc, min_porder, max_porder,
-                                           res, n, i+1, sub->obits, precision);
-            if(bits[i] < bits[opt_order]) {
-                opt_order = i;
-            }
-        }
-        opt_order++;
-    } else if(omethod == ORDER_METHOD_LOG) {
-        uint32_t bits[MAX_LPC_ORDER];
-        int step;
-
-        opt_order= min_order - 1 + (max_order-min_order)/3;
-        memset(bits, -1, sizeof(bits));
-
-        for(step=16 ;step; step>>=1){
-            int last= opt_order;
-            for(i=last-step; i<=last+step; i+= step){
-                if(i<min_order-1 || i>=max_order || bits[i] < UINT32_MAX)
-                    continue;
-                encode_residual_lpc(res, smp, n, i+1, coefs[i], shift[i]);
-                bits[i] = calc_rice_params_lpc(&sub->rc, min_porder, max_porder,
-                                            res, n, i+1, sub->obits, precision);
-                if(bits[i] < bits[opt_order])
-                    opt_order= i;
-            }
-        }
-        opt_order++;
-    }
-
-    sub->order = opt_order;
-    sub->type = FLAC_SUBFRAME_LPC;
-    sub->type_code = sub->type | (sub->order-1);
-    sub->shift = shift[sub->order-1];
-    for(i=0; i<sub->order; i++) {
-        sub->coefs[i] = coefs[sub->order-1][i];
-    }
-    encode_residual_lpc(res, smp, n, sub->order, sub->coefs, sub->shift);
-    return calc_rice_params_lpc(&sub->rc, min_porder, max_porder, res, n, sub->order,
-                                sub->obits, precision);
-}
-
-static int encode_residual_v(FlacEncodeContext *ctx, int ch)
-{
-    int i, n;
-    FlacFrame *frame;
-    FlacSubframe *sub;
-    int32_t *res, *smp;
-
-    frame = &ctx->frame;
-    sub = &frame->subframes[ch];
-    res = sub->residual;
-    smp = sub->samples;
-    n = frame->blocksize;
-
-    /* CONSTANT */
-    for(i=1; i<n; i++) {
-        if(smp[i] != smp[0]) break;
-    }
-    if(i == n) {
-        sub->type = sub->type_code = FLAC_SUBFRAME_CONSTANT;
-        res[0] = smp[0];
-        return sub->obits;
-    }
-
-    /* VERBATIM */
-    sub->type = sub->type_code = FLAC_SUBFRAME_VERBATIM;
-    encode_residual_verbatim(res, smp, n);
-    return sub->obits * n;
-}
-
-static int estimate_stereo_mode(int32_t *left_ch, int32_t *right_ch, int n)
-{
-    int i, best;
-    int32_t lt, rt;
-    uint64_t sum[4];
-    uint64_t score[4];
-    int k;
-
-    /* calculate sum of 2nd order residual for each channel */
-    sum[0] = sum[1] = sum[2] = sum[3] = 0;
-    for(i=2; i<n; i++) {
-        lt = left_ch[i] - 2*left_ch[i-1] + left_ch[i-2];
-        rt = right_ch[i] - 2*right_ch[i-1] + right_ch[i-2];
-        sum[2] += FFABS((lt + rt) >> 1);
-        sum[3] += FFABS(lt - rt);
-        sum[0] += FFABS(lt);
-        sum[1] += FFABS(rt);
-    }
-    /* estimate bit counts */
-    for(i=0; i<4; i++) {
-        k = find_optimal_param(2*sum[i], n);
-        sum[i] = rice_encode_count(2*sum[i], n, k);
-    }
-
-    /* calculate score for each mode */
-    score[0] = sum[0] + sum[1];
-    score[1] = sum[0] + sum[3];
-    score[2] = sum[1] + sum[3];
-    score[3] = sum[2] + sum[3];
-
-    /* return mode with lowest score */
-    best = 0;
-    for(i=1; i<4; i++) {
-        if(score[i] < score[best]) {
-            best = i;
-        }
-    }
-    if(best == 0) {
-        return FLAC_CHMODE_LEFT_RIGHT;
-    } else if(best == 1) {
-        return FLAC_CHMODE_LEFT_SIDE;
-    } else if(best == 2) {
-        return FLAC_CHMODE_RIGHT_SIDE;
-    } else {
-        return FLAC_CHMODE_MID_SIDE;
-    }
-}
-
-/**
- * Perform stereo channel decorrelation
- */
-static void channel_decorrelation(FlacEncodeContext *ctx)
-{
-    FlacFrame *frame;
-    int32_t *left, *right;
-    int i, n;
-
-    frame = &ctx->frame;
-    n = frame->blocksize;
-    left  = frame->subframes[0].samples;
-    right = frame->subframes[1].samples;
-
-    if(ctx->channels != 2) {
-        frame->ch_mode = FLAC_CHMODE_NOT_STEREO;
-        return;
-    }
-
-    frame->ch_mode = estimate_stereo_mode(left, right, n);
-
-    /* perform decorrelation and adjust bits-per-sample */
-    if(frame->ch_mode == FLAC_CHMODE_LEFT_RIGHT) {
-        return;
-    }
-    if(frame->ch_mode == FLAC_CHMODE_MID_SIDE) {
-        int32_t tmp;
-        for(i=0; i<n; i++) {
-            tmp = left[i];
-            left[i] = (tmp + right[i]) >> 1;
-            right[i] = tmp - right[i];
-        }
-        frame->subframes[1].obits++;
-    } else if(frame->ch_mode == FLAC_CHMODE_LEFT_SIDE) {
-        for(i=0; i<n; i++) {
-            right[i] = left[i] - right[i];
-        }
-        frame->subframes[1].obits++;
-    } else {
-        for(i=0; i<n; i++) {
-            left[i] -= right[i];
-        }
-        frame->subframes[0].obits++;
-    }
-}
-
-static void write_utf8(PutBitContext *pb, uint32_t val)
-{
-    uint8_t tmp;
-    PUT_UTF8(val, tmp, put_bits(pb, 8, tmp);)
-}
-
-static void output_frame_header(FlacEncodeContext *s)
-{
-    FlacFrame *frame;
-    int crc;
-
-    frame = &s->frame;
-
-    put_bits(&s->pb, 16, 0xFFF8);
-    put_bits(&s->pb, 4, frame->bs_code[0]);
-    put_bits(&s->pb, 4, s->sr_code[0]);
-    if(frame->ch_mode == FLAC_CHMODE_NOT_STEREO) {
-        put_bits(&s->pb, 4, s->ch_code);
-    } else {
-        put_bits(&s->pb, 4, frame->ch_mode);
-    }
-    put_bits(&s->pb, 3, 4); /* bits-per-sample code */
-    put_bits(&s->pb, 1, 0);
-    write_utf8(&s->pb, s->frame_count);
-    if(frame->bs_code[0] == 6) {
-        put_bits(&s->pb, 8, frame->bs_code[1]);
-    } else if(frame->bs_code[0] == 7) {
-        put_bits(&s->pb, 16, frame->bs_code[1]);
-    }
-    if(s->sr_code[0] == 12) {
-        put_bits(&s->pb, 8, s->sr_code[1]);
-    } else if(s->sr_code[0] > 12) {
-        put_bits(&s->pb, 16, s->sr_code[1]);
-    }
-    flush_put_bits(&s->pb);
-    crc = av_crc(av_crc_get_table(AV_CRC_8_ATM), 0,
-                 s->pb.buf, put_bits_count(&s->pb)>>3);
-    put_bits(&s->pb, 8, crc);
-}
-
-static void output_subframe_constant(FlacEncodeContext *s, int ch)
-{
-    FlacSubframe *sub;
-    int32_t res;
-
-    sub = &s->frame.subframes[ch];
-    res = sub->residual[0];
-    put_sbits(&s->pb, sub->obits, res);
-}
-
-static void output_subframe_verbatim(FlacEncodeContext *s, int ch)
-{
-    int i;
-    FlacFrame *frame;
-    FlacSubframe *sub;
-    int32_t res;
-
-    frame = &s->frame;
-    sub = &frame->subframes[ch];
-
-    for(i=0; i<frame->blocksize; i++) {
-        res = sub->residual[i];
-        put_sbits(&s->pb, sub->obits, res);
-    }
-}
-
-static void output_residual(FlacEncodeContext *ctx, int ch)
-{
-    int i, j, p, n, parts;
-    int k, porder, psize, res_cnt;
-    FlacFrame *frame;
-    FlacSubframe *sub;
-    int32_t *res;
-
-    frame = &ctx->frame;
-    sub = &frame->subframes[ch];
-    res = sub->residual;
-    n = frame->blocksize;
-
-    /* rice-encoded block */
-    put_bits(&ctx->pb, 2, 0);
-
-    /* partition order */
-    porder = sub->rc.porder;
-    psize = n >> porder;
-    parts = (1 << porder);
-    put_bits(&ctx->pb, 4, porder);
-    res_cnt = psize - sub->order;
-
-    /* residual */
-    j = sub->order;
-    for(p=0; p<parts; p++) {
-        k = sub->rc.params[p];
-        put_bits(&ctx->pb, 4, k);
-        if(p == 1) res_cnt = psize;
-        for(i=0; i<res_cnt && j<n; i++, j++) {
-            set_sr_golomb_flac(&ctx->pb, res[j], k, INT32_MAX, 0);
-        }
-    }
-}
-
-static void output_subframe_fixed(FlacEncodeContext *ctx, int ch)
-{
-    int i;
-    FlacFrame *frame;
-    FlacSubframe *sub;
-
-    frame = &ctx->frame;
-    sub = &frame->subframes[ch];
-
-    /* warm-up samples */
-    for(i=0; i<sub->order; i++) {
-        put_sbits(&ctx->pb, sub->obits, sub->residual[i]);
-    }
-
-    /* residual */
-    output_residual(ctx, ch);
-}
-
-static void output_subframe_lpc(FlacEncodeContext *ctx, int ch)
-{
-    int i, cbits;
-    FlacFrame *frame;
-    FlacSubframe *sub;
-
-    frame = &ctx->frame;
-    sub = &frame->subframes[ch];
-
-    /* warm-up samples */
-    for(i=0; i<sub->order; i++) {
-        put_sbits(&ctx->pb, sub->obits, sub->residual[i]);
-    }
-
-    /* LPC coefficients */
-    cbits = ctx->options.lpc_coeff_precision;
-    put_bits(&ctx->pb, 4, cbits-1);
-    put_sbits(&ctx->pb, 5, sub->shift);
-    for(i=0; i<sub->order; i++) {
-        put_sbits(&ctx->pb, cbits, sub->coefs[i]);
-    }
-
-    /* residual */
-    output_residual(ctx, ch);
-}
-
-static void output_subframes(FlacEncodeContext *s)
-{
-    FlacFrame *frame;
-    FlacSubframe *sub;
-    int ch;
-
-    frame = &s->frame;
-
-    for(ch=0; ch<s->channels; ch++) {
-        sub = &frame->subframes[ch];
-
-        /* subframe header */
-        put_bits(&s->pb, 1, 0);
-        put_bits(&s->pb, 6, sub->type_code);
-        put_bits(&s->pb, 1, 0); /* no wasted bits */
-
-        /* subframe */
-        if(sub->type == FLAC_SUBFRAME_CONSTANT) {
-            output_subframe_constant(s, ch);
-        } else if(sub->type == FLAC_SUBFRAME_VERBATIM) {
-            output_subframe_verbatim(s, ch);
-        } else if(sub->type == FLAC_SUBFRAME_FIXED) {
-            output_subframe_fixed(s, ch);
-        } else if(sub->type == FLAC_SUBFRAME_LPC) {
-            output_subframe_lpc(s, ch);
-        }
-    }
-}
-
-static void output_frame_footer(FlacEncodeContext *s)
-{
-    int crc;
-    flush_put_bits(&s->pb);
-    crc = bswap_16(av_crc(av_crc_get_table(AV_CRC_16_ANSI), 0,
-                          s->pb.buf, put_bits_count(&s->pb)>>3));
-    put_bits(&s->pb, 16, crc);
-    flush_put_bits(&s->pb);
-}
-
-static int flac_encode_frame(AVCodecContext *avctx, uint8_t *frame,
-                             int buf_size, void *data)
-{
-    int ch;
-    FlacEncodeContext *s;
-    int16_t *samples = data;
-    int out_bytes;
-
-    s = avctx->priv_data;
-
-    init_frame(s);
-
-    copy_samples(s, samples);
-
-    channel_decorrelation(s);
-
-    for(ch=0; ch<s->channels; ch++) {
-        encode_residual(s, ch);
-    }
-    init_put_bits(&s->pb, frame, buf_size);
-    output_frame_header(s);
-    output_subframes(s);
-    output_frame_footer(s);
-    out_bytes = put_bits_count(&s->pb) >> 3;
-
-    if(out_bytes > s->max_framesize || out_bytes >= buf_size) {
-        /* frame too large. use verbatim mode */
-        for(ch=0; ch<s->channels; ch++) {
-            encode_residual_v(s, ch);
-        }
-        init_put_bits(&s->pb, frame, buf_size);
-        output_frame_header(s);
-        output_subframes(s);
-        output_frame_footer(s);
-        out_bytes = put_bits_count(&s->pb) >> 3;
-
-        if(out_bytes > s->max_framesize || out_bytes >= buf_size) {
-            /* still too large. must be an error. */
-            av_log(avctx, AV_LOG_ERROR, "error encoding frame\n");
-            return -1;
-        }
-    }
-
-    s->frame_count++;
-    return out_bytes;
-}
-
-static av_cold int flac_encode_close(AVCodecContext *avctx)
-{
-    av_freep(&avctx->extradata);
-    avctx->extradata_size = 0;
-    av_freep(&avctx->coded_frame);
-    return 0;
-}
+                          int *shift, int use_lpc, int omethod, int max_shift, int zero_shift);
 
-AVCodec flac_encoder = {
-    "flac",
-    CODEC_TYPE_AUDIO,
-    CODEC_ID_FLAC,
-    sizeof(FlacEncodeContext),
-    flac_encode_init,
-    flac_encode_frame,
-    flac_encode_close,
-    NULL,
-    .capabilities = CODEC_CAP_SMALL_LAST_FRAME,
-    .sample_fmts = (enum SampleFormat[]){SAMPLE_FMT_S16,SAMPLE_FMT_NONE},
-    .long_name = NULL_IF_CONFIG_SMALL("FLAC (Free Lossless Audio Codec)"),
-};
+#endif /* FFMPEG_LPC_H */




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