2x faster ff_h264_init_cabac_states(), 4k cpu cycles less.

[ffmpeg] / libavcodec / mpeg12.c

diff --git a/libavcodec/mpeg12.c b/libavcodec/mpeg12.c
index 2e2bc367b121e8f8a8a4ee51af15f4abebd70e2e..7eddabcaca56fb3c0b9c9ec105addea681d6aa2d 100644 (file)
--- a/libavcodec/mpeg12.c
+++ b/libavcodec/mpeg12.c
@@ -1557,7 +1557,7 @@ static void mpeg_decode_picture_coding_extension(Mpeg1Context *s1)
         s->picture_structure= PICT_FRAME;
     }
 
-    if(s->progressive_frame && !s->frame_pred_frame_dct){
+    if(s->progressive_sequence && !s->frame_pred_frame_dct){
         av_log(s->avctx, AV_LOG_ERROR, "invalid frame_pred_frame_dct\n");
         s->frame_pred_frame_dct= 1;
     }
@@ -1673,10 +1673,7 @@ static int mpeg_decode_slice(Mpeg1Context *s1, int mb_y,
     s->resync_mb_x=
     s->resync_mb_y= -1;
 
-    if (mb_y >= s->mb_height){
-        av_log(s->avctx, AV_LOG_ERROR, "slice below image (%d >= %d)\n", mb_y, s->mb_height);
-        return -1;
-    }
+    assert(mb_y < s->mb_height);
 
     init_get_bits(&s->gb, *buf, buf_size*8);
 
@@ -1697,22 +1694,27 @@ static int mpeg_decode_slice(Mpeg1Context *s1, int mb_y,
 
     s->mb_x=0;
 
-    for(;;) {
-        int code = get_vlc2(&s->gb, mbincr_vlc.table, MBINCR_VLC_BITS, 2);
-        if (code < 0){
-            av_log(s->avctx, AV_LOG_ERROR, "first mb_incr damaged\n");
-            return -1;
-        }
-        if (code >= 33) {
-            if (code == 33) {
-                s->mb_x += 33;
+    if(mb_y==0 && s->codec_tag == AV_RL32("SLIF")){
+        skip_bits1(&s->gb);
+    }else{
+        for(;;) {
+            int code = get_vlc2(&s->gb, mbincr_vlc.table, MBINCR_VLC_BITS, 2);
+            if (code < 0){
+                av_log(s->avctx, AV_LOG_ERROR, "first mb_incr damaged\n");
+                return -1;
+            }
+            if (code >= 33) {
+                if (code == 33) {
+                    s->mb_x += 33;
+                }
+                /* otherwise, stuffing, nothing to do */
+            } else {
+                s->mb_x += code;
+                break;
             }
-            /* otherwise, stuffing, nothing to do */
-        } else {
-            s->mb_x += code;
-            break;
         }
     }
+
     if(s->mb_x >= (unsigned)s->mb_width){
         av_log(s->avctx, AV_LOG_ERROR, "initial skip overflow\n");
         return -1;
@@ -2090,6 +2092,9 @@ static int vcr2_init_sequence(AVCodecContext *avctx)
     s->chroma_format = 1;
     s->codec_id= s->avctx->codec_id= CODEC_ID_MPEG2VIDEO;
     avctx->sub_id = 2; /* indicates MPEG-2 */
+    s1->save_width           = s->width;
+    s1->save_height          = s->height;
+    s1->save_progressive_seq = s->progressive_sequence;
     return 0;
 }
 
@@ -2390,6 +2395,11 @@ static int decode_chunks(AVCodecContext *avctx,
                 if(s2->picture_structure == PICT_BOTTOM_FIELD)
                     mb_y++;
 
+                if (mb_y >= s2->mb_height){
+                    av_log(s2->avctx, AV_LOG_ERROR, "slice below image (%d >= %d)\n", mb_y, s2->mb_height);
+                    return -1;
+                }
+
                 if(s2->last_picture_ptr==NULL){
                 /* Skip B-frames if we do not have reference frames and gop is not closed */
                     if(s2->pict_type==FF_B_TYPE){