there are divx5? encoded files without a userdata section but with b-frames :(

Originally committed as revision 446 to svn://svn.ffmpeg.org/ffmpeg/trunk

1 files changed, 7 insertions, 5 deletions

diff --git a/libavcodec/h263.c b/libavcodec/h263.c
index e20381da02..e654e19281 100644
--- a/libavcodec/h263.c
+++ b/libavcodec/h263.c
@@ -2747,7 +2747,6 @@ int mpeg4_decode_picture_header(MpegEncContext * s)
 {
     int time_incr, startcode, state, v;
     int time_increment;
-    int vol_control=-1;
 
  redo:
     /* search next start code */
@@ -2791,7 +2790,7 @@ int mpeg4_decode_picture_header(MpegEncContext * s)
             skip_bits(&s->gb, 8); // par_height
         }
 
-        if ((vol_control=get_bits1(&s->gb))) { /* vol control parameter */
+        if ((s->vol_control_parameters=get_bits1(&s->gb))) { /* vol control parameter */
             int chroma_format= get_bits(&s->gb, 2);
             if(chroma_format!=1){
                 printf("illegal chroma format\n");
@@ -3000,6 +2999,10 @@ int mpeg4_decode_picture_header(MpegEncContext * s)
     }
 
     s->pict_type = get_bits(&s->gb, 2) + I_TYPE;	/* pict type: I = 0 , P = 1 */
+    if(s->pict_type==B_TYPE && s->low_delay && s->vol_control_parameters==0){
+        printf("low_delay flag set, but shouldnt, clearing it\n");
+        s->low_delay=0;
+    }
 // printf("pic: %d, qpel:%d\n", s->pict_type, s->quarter_sample); 
     time_incr=0;
     while (get_bits1(&s->gb) != 0) 
@@ -3109,9 +3112,8 @@ int mpeg4_decode_picture_header(MpegEncContext * s)
      }
      /* detect buggy encoders which dont set the low_delay flag (divx4/xvid/opendivx)*/
      // note we cannot detect divx5 without b-frames easyly (allthough its buggy too)
-     if(s->vo_type==0 && vol_control==0 && s->divx_version==0){
-         if(s->picture_number==0)
-             printf("looks like this file was encoded with (divx4/(old)xvid/opendivx) -> forcing low_delay flag\n");
+     if(s->vo_type==0 && s->vol_control_parameters==0 && s->divx_version==0 && s->picture_number==0){
+         printf("looks like this file was encoded with (divx4/(old)xvid/opendivx) -> forcing low_delay flag\n");
          s->low_delay=1;
      }