mirror of https://git.ffmpeg.org/ffmpeg.git
If the videos starts with B frame, then the minimum composition time as computed by stts + ctts will be non-zero. Hence we need to shift the DTS, so that the first pts is zero. This was the intention of that code-block. However it was subtracting by the wrong amount. For example, for one of the videos in the bug nonFormatted.mp4 we have stts: sample_count duration 960 1001 ctts: sample_count duration 1 3003 2 0 1 3003 .... The resulting composition times are : 3003, 1001, 2002, 6006, ... The minimum composition time or PTS is 1001, which should be used to offset DTS. However the code block was wrongly using ctts[0] which is 3003. Hence the PTS was negative. This change computes the minimum pts encountered while fixing the index, and then subtracts it from all the timestamps after the edit list fixes are applied. Samples files available from: https://bugs.chromium.org/p/chromium/issues/detail?id=721451 https://bugs.chromium.org/p/chromium/issues/detail?id=723537 fate-suite/h264/twofields_packet.mp4 is a similar file starting with 2 B frames. Before this change the PTS of first two B-frames was -6006 and -3003, and I am guessing one of them got dropped when being decoded and remuxed to the framecrc before, and now it is not being dropped. Signed-off-by: Sasi Inguva <isasi@google.com> |
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api | ||
checkasm | ||
fate | ||
filtergraphs | ||
ref | ||
.gitignore | ||
Makefile | ||
audiogen.c | ||
audiomatch.c | ||
base64.c | ||
copycooker.sh | ||
extended.ffconcat | ||
fate-run.sh | ||
fate-valgrind.supp | ||
fate.sh | ||
ffserver-regression.sh | ||
ffserver.conf | ||
ffserver.regression.ref | ||
lavf-regression.sh | ||
md5.sh | ||
reference.pnm | ||
regression-funcs.sh | ||
rotozoom.c | ||
simple1.ffconcat | ||
simple2.ffconcat | ||
test.ffmeta | ||
tiny_psnr.c | ||
tiny_ssim.c | ||
utils.c | ||
videogen.c |