mpeg4video: Add support for MPEG-4 Simple Studio Profile.

[ffmpeg] / libavcodec / ituh263dec.c

diff --git a/libavcodec/ituh263dec.c b/libavcodec/ituh263dec.c
index fc95a532ce79460d3098cc11d80cce318e7a392f..1b57e53cad9ff934dde788562b61b9748e8e5d72 100644 (file)
--- a/libavcodec/ituh263dec.c
+++ b/libavcodec/ituh263dec.c
@@ -207,12 +207,27 @@ static int h263_decode_gob_header(MpegEncContext *s)
 }
 
 /**
- * Decode the group of blocks / video packet header.
+ * Decode the group of blocks / video packet header / slice header (MPEG-4 Studio).
  * @return bit position of the resync_marker, or <0 if none was found
  */
 int ff_h263_resync(MpegEncContext *s){
     int left, pos, ret;
 
+    /* In MPEG-4 studio mode look for a new slice startcode
+     * and decode slice header */
+    if(s->codec_id==AV_CODEC_ID_MPEG4 && s->studio_profile) {
+        align_get_bits(&s->gb);
+
+        while (get_bits_left(&s->gb) >= 32 && show_bits_long(&s->gb, 32) != SLICE_START_CODE) {
+            get_bits(&s->gb, 8);
+        }
+
+        if (show_bits_long(&s->gb, 32) == SLICE_START_CODE)
+            return get_bits_count(&s->gb);
+        else
+            return -1;
+    }
+
     if(s->codec_id==AV_CODEC_ID_MPEG4){
         skip_bits1(&s->gb);
         align_get_bits(&s->gb);