[FFmpeg-devel] [PATCH 26/29] avformat/matroskaenc: Check return value of ff_isom_write_hvcc()

Andreas Rheinhardt andreas.rheinhardt at gmail.com
Wed Nov 27 09:48:55 EET 2019

The Matroska muxer currently does not check the return value of
ff_isom_write_hvcc(), the function used to write mp4-style
HEVC-extradata as Matroska also uses it. This was intentionally done in
7a5356c72 to allow remuxing from mpeg-ts.

But if ff_isom_write_hvcc() fails, it has not output anything and the
file ends up without CodecPrivate and, if the input was annex b, with
annex b data, which is against the spec. So check the return value

The underlying issue of not having extradata seems to have been fixed by
the introduction of the extract_extradata bitstream filter.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt at gmail.com>
 libavformat/matroskaenc.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/libavformat/matroskaenc.c b/libavformat/matroskaenc.c
index 43966a4378..6e1d575e3f 100644
--- a/libavformat/matroskaenc.c
+++ b/libavformat/matroskaenc.c
@@ -707,9 +707,8 @@ static int mkv_write_native_codecprivate(AVFormatContext *s, AVIOContext *pb,
         return ff_isom_write_avcc(dyn_cp, par->extradata,
     case AV_CODEC_ID_HEVC:
-        ff_isom_write_hvcc(dyn_cp, par->extradata,
-                           par->extradata_size, 0);
-        return 0;
+        return ff_isom_write_hvcc(dyn_cp, par->extradata,
+                                  par->extradata_size, 0);
     case AV_CODEC_ID_AV1:
         if (par->extradata_size)
             return ff_isom_write_av1c(dyn_cp, par->extradata,

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