[FFmpeg-cvslog] VC1: transpose IDCT 8x8 coeffs while reading.

Ronald S. Bultje git
Fri Feb 18 20:38:21 CET 2011


ffmpeg | branch: master | Ronald S. Bultje <rsbultje at gmail.com> | Wed Feb 16 14:18:21 2011 -0500| [2739dc5d858a18c4d10f043af0e31a8a57ca147f] | committer: Michael Niedermayer

VC1: transpose IDCT 8x8 coeffs while reading.
(cherry picked from commit 1da6ea39542424ddb691dc6cf08d611a4c6db247)

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=2739dc5d858a18c4d10f043af0e31a8a57ca147f
---

 libavcodec/ppc/vc1dsp_altivec.c |    1 -
 libavcodec/vc1.h                |    1 +
 libavcodec/vc1dec.c             |   95 ++++++++++++++++++++------------------
 libavcodec/vc1dsp.c             |   24 +++++-----
 4 files changed, 63 insertions(+), 58 deletions(-)

diff --git a/libavcodec/ppc/vc1dsp_altivec.c b/libavcodec/ppc/vc1dsp_altivec.c
index a2f55f2d..5ffe9a5 100644
--- a/libavcodec/ppc/vc1dsp_altivec.c
+++ b/libavcodec/ppc/vc1dsp_altivec.c
@@ -154,7 +154,6 @@ static void vc1_inv_trans_8x8_altivec(DCTELEM block[64])
     src6 = vec_ld( 96, block);
     src7 = vec_ld(112, block);
 
-    TRANSPOSE8(src0, src1, src2, src3, src4, src5, src6, src7);
     s0 = vec_unpackl(src0);
     s1 = vec_unpackl(src1);
     s2 = vec_unpackl(src2);
diff --git a/libavcodec/vc1.h b/libavcodec/vc1.h
index e5a9cba..da0b6c1 100644
--- a/libavcodec/vc1.h
+++ b/libavcodec/vc1.h
@@ -215,6 +215,7 @@ typedef struct VC1Context{
     int k_y;              ///< Number of bits for MVs (depends on MV range)
     int range_x, range_y; ///< MV range
     uint8_t pq, altpq;    ///< Current/alternate frame quantizer scale
+    uint8_t zz_8x8[4][64];///< Zigzag table for TT_8x8, permuted for IDCT
     const uint8_t* zz_8x4;///< Zigzag scan table for TT_8x4 coding mode
     const uint8_t* zz_4x8;///< Zigzag scan table for TT_4x8 coding mode
     /** pquant parameters */
diff --git a/libavcodec/vc1dec.c b/libavcodec/vc1dec.c
index 3bd2cce..169797c 100644
--- a/libavcodec/vc1dec.c
+++ b/libavcodec/vc1dec.c
@@ -1499,11 +1499,11 @@ static int vc1_decode_i_block(VC1Context *v, DCTELEM block[64], int n, int coded
 
         if(v->s.ac_pred) {
             if(!dc_pred_dir)
-                zz_table = wmv1_scantable[2];
+                zz_table = v->zz_8x8[2];
             else
-                zz_table = wmv1_scantable[3];
+                zz_table = v->zz_8x8[3];
         } else
-            zz_table = wmv1_scantable[1];
+            zz_table = v->zz_8x8[1];
 
         ac_val = s->ac_val[0][0] + s->block_index[n] * 16;
         ac_val2 = ac_val;
@@ -1524,16 +1524,16 @@ static int vc1_decode_i_block(VC1Context *v, DCTELEM block[64], int n, int coded
         if(s->ac_pred) {
             if(dc_pred_dir) { //left
                 for(k = 1; k < 8; k++)
-                    block[k << 3] += ac_val[k];
+                    block[k] += ac_val[k];
             } else { //top
                 for(k = 1; k < 8; k++)
-                    block[k] += ac_val[k + 8];
+                    block[k << 3] += ac_val[k + 8];
             }
         }
         /* save AC coeffs for further prediction */
         for(k = 1; k < 8; k++) {
-            ac_val2[k] = block[k << 3];
-            ac_val2[k + 8] = block[k];
+            ac_val2[k] = block[k];
+            ac_val2[k + 8] = block[k << 3];
         }
 
         /* scale AC coeffs */
@@ -1570,15 +1570,15 @@ not_coded:
         if(s->ac_pred) {
             if(dc_pred_dir) { //left
                 for(k = 1; k < 8; k++) {
-                    block[k << 3] = ac_val[k] * scale;
-                    if(!v->pquantizer && block[k << 3])
-                        block[k << 3] += (block[k << 3] < 0) ? -v->pq : v->pq;
+                    block[k] = ac_val[k] * scale;
+                    if(!v->pquantizer && block[k])
+                        block[k] += (block[k] < 0) ? -v->pq : v->pq;
                 }
             } else { //top
                 for(k = 1; k < 8; k++) {
-                    block[k] = ac_val[k + 8] * scale;
-                    if(!v->pquantizer && block[k])
-                        block[k] += (block[k] < 0) ? -v->pq : v->pq;
+                    block[k << 3] = ac_val[k + 8] * scale;
+                    if(!v->pquantizer && block[k << 3])
+                        block[k << 3] += (block[k << 3] < 0) ? -v->pq : v->pq;
                 }
             }
             i = 63;
@@ -1682,11 +1682,11 @@ static int vc1_decode_i_block_adv(VC1Context *v, DCTELEM block[64], int n, int c
 
         if(v->s.ac_pred) {
             if(!dc_pred_dir)
-                zz_table = wmv1_scantable[2];
+                zz_table = v->zz_8x8[2];
             else
-                zz_table = wmv1_scantable[3];
+                zz_table = v->zz_8x8[3];
         } else
-            zz_table = wmv1_scantable[1];
+            zz_table = v->zz_8x8[1];
 
         while (!last) {
             vc1_decode_ac_coeff(v, &last, &skip, &value, codingset);
@@ -1705,25 +1705,25 @@ static int vc1_decode_i_block_adv(VC1Context *v, DCTELEM block[64], int n, int c
 
                 if(dc_pred_dir) { //left
                     for(k = 1; k < 8; k++)
-                        block[k << 3] += (ac_val[k] * q2 * ff_vc1_dqscale[q1 - 1] + 0x20000) >> 18;
+                        block[k] += (ac_val[k] * q2 * ff_vc1_dqscale[q1 - 1] + 0x20000) >> 18;
                 } else { //top
                     for(k = 1; k < 8; k++)
-                        block[k] += (ac_val[k + 8] * q2 * ff_vc1_dqscale[q1 - 1] + 0x20000) >> 18;
+                        block[k << 3] += (ac_val[k + 8] * q2 * ff_vc1_dqscale[q1 - 1] + 0x20000) >> 18;
                 }
             } else {
                 if(dc_pred_dir) { //left
                     for(k = 1; k < 8; k++)
-                        block[k << 3] += ac_val[k];
+                        block[k] += ac_val[k];
                 } else { //top
                     for(k = 1; k < 8; k++)
-                        block[k] += ac_val[k + 8];
+                        block[k << 3] += ac_val[k + 8];
                 }
             }
         }
         /* save AC coeffs for further prediction */
         for(k = 1; k < 8; k++) {
-            ac_val2[k] = block[k << 3];
-            ac_val2[k + 8] = block[k];
+            ac_val2[k] = block[k];
+            ac_val2[k + 8] = block[k << 3];
         }
 
         /* scale AC coeffs */
@@ -1765,15 +1765,15 @@ static int vc1_decode_i_block_adv(VC1Context *v, DCTELEM block[64], int n, int c
         if(use_pred) {
             if(dc_pred_dir) { //left
                 for(k = 1; k < 8; k++) {
-                    block[k << 3] = ac_val2[k] * scale;
-                    if(!v->pquantizer && block[k << 3])
-                        block[k << 3] += (block[k << 3] < 0) ? -mquant : mquant;
+                    block[k] = ac_val2[k] * scale;
+                    if(!v->pquantizer && block[k])
+                        block[k] += (block[k] < 0) ? -mquant : mquant;
                 }
             } else { //top
                 for(k = 1; k < 8; k++) {
-                    block[k] = ac_val2[k + 8] * scale;
-                    if(!v->pquantizer && block[k])
-                        block[k] += (block[k] < 0) ? -mquant : mquant;
+                    block[k << 3] = ac_val2[k + 8] * scale;
+                    if(!v->pquantizer && block[k << 3])
+                        block[k << 3] += (block[k << 3] < 0) ? -mquant : mquant;
                 }
             }
             i = 63;
@@ -1884,17 +1884,14 @@ static int vc1_decode_intra_block(VC1Context *v, DCTELEM block[64], int n, int c
 
     if(coded) {
         int last = 0, skip, value;
-        const uint8_t *zz_table;
         int k;
 
-        zz_table = wmv1_scantable[0];
-
         while (!last) {
             vc1_decode_ac_coeff(v, &last, &skip, &value, codingset);
             i += skip;
             if(i > 63)
                 break;
-            block[zz_table[i++]] = value;
+            block[v->zz_8x8[0][i++]] = value;
         }
 
         /* apply AC prediction if needed */
@@ -1906,25 +1903,25 @@ static int vc1_decode_intra_block(VC1Context *v, DCTELEM block[64], int n, int c
 
                 if(dc_pred_dir) { //left
                     for(k = 1; k < 8; k++)
-                        block[k << 3] += (ac_val[k] * q2 * ff_vc1_dqscale[q1 - 1] + 0x20000) >> 18;
+                        block[k] += (ac_val[k] * q2 * ff_vc1_dqscale[q1 - 1] + 0x20000) >> 18;
                 } else { //top
                     for(k = 1; k < 8; k++)
-                        block[k] += (ac_val[k + 8] * q2 * ff_vc1_dqscale[q1 - 1] + 0x20000) >> 18;
+                        block[k << 3] += (ac_val[k + 8] * q2 * ff_vc1_dqscale[q1 - 1] + 0x20000) >> 18;
                 }
             } else {
                 if(dc_pred_dir) { //left
                     for(k = 1; k < 8; k++)
-                        block[k << 3] += ac_val[k];
+                        block[k] += ac_val[k];
                 } else { //top
                     for(k = 1; k < 8; k++)
-                        block[k] += ac_val[k + 8];
+                        block[k << 3] += ac_val[k + 8];
                 }
             }
         }
         /* save AC coeffs for further prediction */
         for(k = 1; k < 8; k++) {
-            ac_val2[k] = block[k << 3];
-            ac_val2[k + 8] = block[k];
+            ac_val2[k] = block[k];
+            ac_val2[k + 8] = block[k << 3];
         }
 
         /* scale AC coeffs */
@@ -1966,15 +1963,15 @@ static int vc1_decode_intra_block(VC1Context *v, DCTELEM block[64], int n, int c
         if(use_pred) {
             if(dc_pred_dir) { //left
                 for(k = 1; k < 8; k++) {
-                    block[k << 3] = ac_val2[k] * scale;
-                    if(!v->pquantizer && block[k << 3])
-                        block[k << 3] += (block[k << 3] < 0) ? -mquant : mquant;
+                    block[k] = ac_val2[k] * scale;
+                    if(!v->pquantizer && block[k])
+                        block[k] += (block[k] < 0) ? -mquant : mquant;
                 }
             } else { //top
                 for(k = 1; k < 8; k++) {
-                    block[k] = ac_val2[k + 8] * scale;
-                    if(!v->pquantizer && block[k])
-                        block[k] += (block[k] < 0) ? -mquant : mquant;
+                    block[k << 3] = ac_val2[k + 8] * scale;
+                    if(!v->pquantizer && block[k << 3])
+                        block[k << 3] += (block[k << 3] < 0) ? -mquant : mquant;
                 }
             }
             i = 63;
@@ -2035,7 +2032,7 @@ static int vc1_decode_p_block(VC1Context *v, DCTELEM block[64], int n, int mquan
             i += skip;
             if(i > 63)
                 break;
-            idx = wmv1_scantable[0][i++];
+            idx = v->zz_8x8[0][i++];
             block[idx] = value * scale;
             if(!v->pquantizer)
                 block[idx] += (block[idx] < 0) ? -mquant : mquant;
@@ -3007,6 +3004,7 @@ static av_cold int vc1_decode_init(AVCodecContext *avctx)
     VC1Context *v = avctx->priv_data;
     MpegEncContext *s = &v->s;
     GetBitContext gb;
+    int i;
 
     if (!avctx->extradata_size || !avctx->extradata) return -1;
     if (!(avctx->flags & CODEC_FLAG_GRAY))
@@ -3025,6 +3023,13 @@ static av_cold int vc1_decode_init(AVCodecContext *avctx)
     if(ff_msmpeg4_decode_init(avctx) < 0)
         return -1;
     if (vc1_init_common(v) < 0) return -1;
+    for (i = 0; i < 64;  i++) {
+#define transpose(x) ((x>>3) | ((x&7)<<3))
+        v->zz_8x8[0][i] = transpose(wmv1_scantable[0][i]);
+        v->zz_8x8[1][i] = transpose(wmv1_scantable[1][i]);
+        v->zz_8x8[2][i] = transpose(wmv1_scantable[2][i]);
+        v->zz_8x8[3][i] = transpose(wmv1_scantable[3][i]);
+    }
 
     avctx->coded_width = avctx->width;
     avctx->coded_height = avctx->height;
diff --git a/libavcodec/vc1dsp.c b/libavcodec/vc1dsp.c
index aab1694..fd740e1 100644
--- a/libavcodec/vc1dsp.c
+++ b/libavcodec/vc1dsp.c
@@ -203,25 +203,25 @@ static void vc1_inv_trans_8x8_c(DCTELEM block[64])
 {
     int i;
     register int t1,t2,t3,t4,t5,t6,t7,t8;
-    DCTELEM *src, *dst;
+    DCTELEM *src, *dst, temp[64];
 
     src = block;
-    dst = block;
+    dst = temp;
     for(i = 0; i < 8; i++){
-        t1 = 12 * (src[0] + src[4]) + 4;
-        t2 = 12 * (src[0] - src[4]) + 4;
-        t3 = 16 * src[2] +  6 * src[6];
-        t4 =  6 * src[2] - 16 * src[6];
+        t1 = 12 * (src[ 0] + src[32]) + 4;
+        t2 = 12 * (src[ 0] - src[32]) + 4;
+        t3 = 16 * src[16] +  6 * src[48];
+        t4 =  6 * src[16] - 16 * src[48];
 
         t5 = t1 + t3;
         t6 = t2 + t4;
         t7 = t2 - t4;
         t8 = t1 - t3;
 
-        t1 = 16 * src[1] + 15 * src[3] +  9 * src[5] +  4 * src[7];
-        t2 = 15 * src[1] -  4 * src[3] - 16 * src[5] -  9 * src[7];
-        t3 =  9 * src[1] - 16 * src[3] +  4 * src[5] + 15 * src[7];
-        t4 =  4 * src[1] -  9 * src[3] + 15 * src[5] - 16 * src[7];
+        t1 = 16 * src[ 8] + 15 * src[24] +  9 * src[40] +  4 * src[56];
+        t2 = 15 * src[ 8] -  4 * src[24] - 16 * src[40] -  9 * src[56];
+        t3 =  9 * src[ 8] - 16 * src[24] +  4 * src[40] + 15 * src[56];
+        t4 =  4 * src[ 8] -  9 * src[24] + 15 * src[40] - 16 * src[56];
 
         dst[0] = (t5 + t1) >> 3;
         dst[1] = (t6 + t2) >> 3;
@@ -232,11 +232,11 @@ static void vc1_inv_trans_8x8_c(DCTELEM block[64])
         dst[6] = (t6 - t2) >> 3;
         dst[7] = (t5 - t1) >> 3;
 
-        src += 8;
+        src += 1;
         dst += 8;
     }
 
-    src = block;
+    src = temp;
     dst = block;
     for(i = 0; i < 8; i++){
         t1 = 12 * (src[ 0] + src[32]) + 64;




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