diff options
| author | Lucas Cooper <bobobo-at-google.com@ffmpeg.org> | 2017-04-27 15:08:29 -0700 |
|---|---|---|
| committer | Michael Niedermayer <michael@niedermayer.cc> | 2017-04-29 03:54:31 +0200 |
| commit | 77bc507f6f001b9f5fa75c664106261bd8f2c971 (patch) | |
| tree | f11b3dfc939e43c03df364a37679469e68919bc0 /libavformat/movenc.c | |
| parent | 1bee78a0198decb73619115f7e760be6b7d010e5 (diff) | |
avformat/movenc: Explicitly address potential division by zero.
find_fps attempts to infer framerate from AVCodec's timebase. When this
results in a frame rate that isn't explicitly marked as supported in
av_timecode_check_frame_rate, find_fps returns the AVStream's
avg_frame_rate, which, per avformat.h, _may_ be set (or not).
mov_get_mpeg2_xdcam_codec_tag, mov_get_h264_codec_tag and
find_compressor attempt to call av_q2d on the return value of find_fps,
which in the above case, may result in division by zero and therefore,
an undefined frame rate when NaN is converted to int.
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
Diffstat (limited to 'libavformat/movenc.c')
| -rw-r--r-- | libavformat/movenc.c | 15 |
1 files changed, 12 insertions, 3 deletions
diff --git a/libavformat/movenc.c b/libavformat/movenc.c index e6e2313c53..d20d272f89 100644 --- a/libavformat/movenc.c +++ b/libavformat/movenc.c @@ -1321,12 +1321,21 @@ static AVRational find_fps(AVFormatContext *s, AVStream *st) return rate; } +static int defined_frame_rate(AVFormatContext *s, AVStream *st) +{ + AVRational rational_framerate = find_fps(s, st); + int rate = 0; + if (rational_framerate.den != 0) + rate = av_q2d(rational_framerate); + return rate; +} + static int mov_get_mpeg2_xdcam_codec_tag(AVFormatContext *s, MOVTrack *track) { int tag = track->par->codec_tag; int interlaced = track->par->field_order > AV_FIELD_PROGRESSIVE; AVStream *st = track->st; - int rate = av_q2d(find_fps(s, st)); + int rate = defined_frame_rate(s, st); if (!tag) tag = MKTAG('m', '2', 'v', '1'); //fallback tag @@ -1388,7 +1397,7 @@ static int mov_get_h264_codec_tag(AVFormatContext *s, MOVTrack *track) int tag = track->par->codec_tag; int interlaced = track->par->field_order > AV_FIELD_PROGRESSIVE; AVStream *st = track->st; - int rate = av_q2d(find_fps(s, st)); + int rate = defined_frame_rate(s, st); if (!tag) tag = MKTAG('a', 'v', 'c', 'i'); //fallback tag @@ -1850,7 +1859,7 @@ static void find_compressor(char * compressor_name, int len, MOVTrack *track) } else if (track->par->codec_id == AV_CODEC_ID_MPEG2VIDEO && xdcam_res) { int interlaced = track->par->field_order > AV_FIELD_PROGRESSIVE; AVStream *st = track->st; - int rate = av_q2d(find_fps(NULL, st)); + int rate = defined_frame_rate(NULL, st); av_strlcatf(compressor_name, len, "XDCAM"); if (track->par->format == AV_PIX_FMT_YUV422P) { av_strlcatf(compressor_name, len, " HD422"); |