better cbp handling and small speedup in mpeg12

Originally committed as revision 3219 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/mpeg12.c

@@ -1038,7 +1038,8 @@ static int mpeg_decode_mb(MpegEncContext *s,
                           DCTELEM block[12][64])
 {
     int i, j, k, cbp, val, mb_type, motion_type;
-    
+    const int mb_block_count = 4 + (1<< s->chroma_format)
+
     dprintf("decode_mb: x=%d y=%d\n", s->mb_x, s->mb_y);
 
     assert(s->mb_skiped==0);
@@ -1151,7 +1152,7 @@ static int mpeg_decode_mb(MpegEncContext *s,
 #endif
 
         if (s->codec_id == CODEC_ID_MPEG2VIDEO) {
-            for(i=0;i<4+(1<<s->chroma_format);i++) {
+            for(i=0;i<mb_block_count;i++) {
                 if (mpeg2_decode_block_intra(s, s->pblocks[i], i) < 0)
                     return -1;
             }
@@ -1335,11 +1336,9 @@ static int mpeg_decode_mb(MpegEncContext *s,
                 av_log(s->avctx, AV_LOG_ERROR, "invalid cbp at %d %d\n", s->mb_x, s->mb_y);
                 return -1;
             }
-            if(s->chroma_format == 2){//CHROMA422
+            if(mb_block_count > 6){
-                 cbp|= ( get_bits(&s->gb,2) ) << 6;
+	         cbp<<= mb_block_count-6;
-            }else
+		 cbp |= get_bits(&s->gb, mb_block_count-6);
-            if(s->chroma_format >  2){//CHROMA444
-                 cbp|= ( get_bits(&s->gb,6) ) << 6;
             }
 
 #ifdef HAVE_XVMC
@@ -1353,34 +1352,16 @@ static int mpeg_decode_mb(MpegEncContext *s,
 #endif
 
             if (s->codec_id == CODEC_ID_MPEG2VIDEO) {
-                for(i=0;i<6;i++) {
+                cbp<<= 12-mb_block_count;
-                    if (cbp & (1<<(5-i)) ) {
+
+                for(i=0;i<mb_block_count;i++) {
+                    if ( cbp & (1<<11) ) {
                         if (mpeg2_decode_block_non_intra(s, s->pblocks[i], i) < 0)
                             return -1;
                     } else {
                         s->block_last_index[i] = -1;
                     }
-                }
+                    cbp+=cbp;
-                if (s->chroma_format >= 2) {
-                    if (s->chroma_format == 2) {//CHROMA_422)
-                        for(i=6;i<8;i++) {
-                            if (cbp & (1<<(6+7-i)) ) {
-                                if (mpeg2_decode_block_non_intra(s, s->pblocks[i], i) < 0)
-                                    return -1;
-                            } else {
-                                s->block_last_index[i] = -1;
-                            }
-                        }
-                    }else{ /*CHROMA_444*/
-                        for(i=6;i<12;i++) {
-                            if (cbp & (1<<(6+11-i)) ) {
-                                if (mpeg2_decode_block_non_intra(s, s->pblocks[i], i) < 0)
-                                    return -1;
-                            } else {
-                                s->block_last_index[i] = -1;
-                            }
-                        }
-                    }
                 }
             } else {
                 for(i=0;i<6;i++) {
@@ -3013,6 +2994,8 @@ AVCodec mpeg2video_encoder = {
 static int mpeg_mc_decode_init(AVCodecContext *avctx){
     Mpeg1Context *s;
 
+    if( avctx->thread_count > 1) 
+        return -1;
     if( !(avctx->slice_flags & SLICE_FLAG_CODED_ORDER) )
         return -1;
     if( !(avctx->slice_flags & SLICE_FLAG_ALLOW_FIELD) ){

libavcodec/xvmcvideo.c

@@ -55,71 +55,21 @@ xvmc_render_state_t * render;
 
 void XVMC_pack_pblocks(MpegEncContext *s, int cbp){
 int i,j;
+const int mb_block_count = 4+(1<<s->chroma_format);
 
     j=0;
-    for(i=0;i<6;i++){
+    cbp<<= 12-mb_block_count;
-        if(cbp & (1<<(5-i)) ){
+    for(i=0; i<mb_block_count; i++){
+        if(cbp & (1<<11)) {
            s->pblocks[i] = (short *)(&s->block[(j++)]);
         }else{
            s->pblocks[i] = NULL;
         }
+	cbp+=cbp;
 //        printf("s->pblocks[%d]=%p ,s->block=%p cbp=%d\n",i,s->pblocks[i],s->block,cbp);
     }
-    if (s->chroma_format >= 2){
-        if (s->chroma_format == 2){//CHROMA_422
-            for(i=6;i<8;i++){
-                if(cbp & (1<<(6+7-i)) ){
-                    s->pblocks[i] = (short *)(&s->block[(j++)]);
-                }else{
-                    s->pblocks[i] = NULL;
-                }
-            }
-        }else{//CHROMA_444
-            for(i=6; i<12; i++){
-                if(cbp & (1<<(6+11-i)) ){
-                    s->pblocks[i] = (short *)(&s->block[(j++)]);
-                }else{
-                    s->pblocks[i] = NULL;
-                }
-            }
-	}
-    }
 }
 
-static int calc_cbp(MpegEncContext *s){
-/* compute cbp */
-int  i,cbp = 0;
-    for(i=0; i<4; i++) {
-        if(s->block_last_index[i] >= 0)
-            cbp |= 1 << (5 - i);
-    }
-    if(s->flags & CODEC_FLAG_GRAY)
-         return cbp; //4 block for grayscale one done
-
-
-    for(i=4; i<6; i++) {
-        if(s->block_last_index[i] >= 0)
-            cbp |= 1 << (5 - i);
-    }
-    if(s->chroma_format <  2) return cbp;
-
-
-    if(s->chroma_format == 2){/*CHROMA_422*/
-        for(i=6; i<8; i++) {
-            if(s->block_last_index[i] >= 0)
-                cbp |= 1 << (6+7 - i);
-        }
-    }else{/*CHROMA_444*/
-        for(i=6; i<12; i++) {
-            if(s->block_last_index[i] >= 0)
-                cbp |= 1 << (6+11 - i);
-        }
-    }
-    return cbp;
-}
-
-
-
 //these functions should be called on every new field or/and frame
 //They should be safe if they are called few times for same field!
 int XVMC_field_start(MpegEncContext*s, AVCodecContext *avctx){
@@ -301,6 +251,14 @@ const int mb_xy = s->mb_y * s->mb_stride + s->mb_x;
         blocks_per_mb = 4 + (1 << (s->chroma_format));
     }
 
+//  calculate cbp
+    cbp = 0;
+    for(i=0; i<blocks_per_mb; i++) {
+        cbp+= cbp;
+        if(s->block_last_index[i] >= 0)
+            cbp++;
+    }
+    
     if(s->flags & CODEC_FLAG_GRAY){
         if(s->mb_intra){//intra frames are alwasy full chroma block
             for(i=4; i<blocks_per_mb; i++){
@@ -308,10 +266,11 @@ const int mb_xy = s->mb_y * s->mb_stride + s->mb_x;
                 if(!render->unsigned_intra)
                     s->pblocks[i][0] = 1<<10;
             }
-        }else
+        }else{
+            cbp&= 0xf << (blocks_per_mb - 4);
             blocks_per_mb = 4;//Luminance blocks only
+        }
     }
-    cbp = calc_cbp(s);
     mv_block->coded_block_pattern = cbp;
     if(cbp == 0)
         mv_block->macroblock_type &= ~XVMC_MB_TYPE_PATTERN;