Ticket #3001: 3001_revert_ffmpeg_6942_and_6953.diff

mythtv/libs/libavcodec/h263.c

@@ -3209 +3209 @@
  * @return 0 if not
  */
 static inline int mpeg4_is_resync(MpegEncContext *s){
-    int bits_count= get_bits_count(&s->gb);
-    int v= show_bits(&s->gb, 16);
+    const int bits_count= get_bits_count(&s->gb);
 
     if(s->workaround_bugs&FF_BUG_NO_PADDING){
         return 0;
     }
 
-    while(v<=0xFF){
-        if(s->pict_type==B_TYPE || (v>>(8-s->pict_type)!=1) || s->partitioned_frame)
-            break;
-        skip_bits(&s->gb, 8+s->pict_type);
-        bits_count+= 8+s->pict_type;
-        v= show_bits(&s->gb, 16);
-    }
-
     if(bits_count + 8 >= s->gb.size_in_bits){
-        v>>=8;
+        int v= show_bits(&s->gb, 8);
         v|= 0x7F >> (7-(bits_count&7));
 
         if(v==0x7F)
             return 1;
     }else{
-        if(v == ff_mpeg4_resync_prefix[bits_count&7]){
+        if(show_bits(&s->gb, 16) == ff_mpeg4_resync_prefix[bits_count&7]){
             int len;
             GetBitContext gb= s->gb;
 
@@ -4550 +4541 @@
 
         /* per-MB end of slice check */
     if(s->codec_id==CODEC_ID_MPEG4){
+#if 0 //http://standards.iso.org/ittf/PubliclyAvailableStandards/ISO_IEC_14496-4_2004_Conformance_Testing/video_conformance/version_1/simple/ERROR.ZIP/mit025.m4v needs this but its unclear if the mpeg4 standard allows this at all (MN)
+        if(s->pict_type != B_TYPE){
+            while(show_bits(&s->gb, 9 + (s->pict_type == P_TYPE)) == 1)
+                skip_bits(&s->gb, 9 + (s->pict_type == P_TYPE));
+        }
+#endif
         if(mpeg4_is_resync(s)){
             const int delta= s->mb_x + 1 == s->mb_width ? 2 : 1;
             if(s->pict_type==B_TYPE && s->next_picture.mbskip_table[xy + delta])