[FFmpeg-devel] [PATCH] avformat/wtvdec: ignore mpeg2 extradata

Peter Ross pross at xvid.org
Thu May 1 14:22:09 CEST 2014


Files produced by windows media center contain meaningless mpeg1 sequence
header. The mpeg2 decoder detects the presence mpeg1 sequence header start
codes and attempts to decode the stream as mpeg1. (This problem introduced
in 73a2d16b.)

Fixes ticket #3601.

Signed-off-by: Peter Ross <pross at xvid.org>
---
 libavformat/wtvdec.c | 14 +-------------
 1 file changed, 1 insertion(+), 13 deletions(-)

diff --git a/libavformat/wtvdec.c b/libavformat/wtvdec.c
index 597a11f..cfdc555 100644
--- a/libavformat/wtvdec.c
+++ b/libavformat/wtvdec.c
@@ -694,19 +694,7 @@ static AVStream * parse_media_type(AVFormatContext *s, AVStream *st, int sid,
             avio_skip(pb, FFMAX(size - consumed, 0));
         } else if (!ff_guidcmp(formattype, ff_format_mpeg2_video)) {
             uint64_t consumed = parse_videoinfoheader2(s, st);
-            if (size - consumed >= 20) {
-                uint32_t count;
-                consumed += 20;
-                avio_skip(pb, 4);
-                count = avio_rl32(pb);
-                count = FFMIN(count, size - consumed);
-                avio_skip(pb, 12);
-                if (count && ff_get_extradata(st->codec, pb, count) < 0) {
-                   ff_free_stream(s, st);
-                   return NULL;
-                }
-                consumed += count;
-            }
+            /* ignore extradata; files produced by windows media center contain meaningless mpeg1 sequence header */
             avio_skip(pb, FFMAX(size - consumed, 0));
         } else {
             if (ff_guidcmp(formattype, ff_format_none))
-- 
1.8.3.2

-- Peter
(A907 E02F A6E5 0CD2 34CD 20D2 6760 79C5 AC40 DD6B)
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