Opened 2 weeks ago
#10991 new defect
Transcoding to x265 causes frozen frames
Reported by: | Yuri Gorokhov | Owned by: | |
---|---|---|---|
Priority: | normal | Component: | undetermined |
Version: | git-master | Keywords: | |
Cc: | Yuri Gorokhov | Blocked By: | |
Blocking: | Reproduced by developer: | no | |
Analyzed by developer: | no |
Description
Summary of the bug:
Transcoding video to x265 results in a few frozen frames in the output video.
How to reproduce:
Download the input video: https://github.com/yurigorokhov/ffmpeg_bug/raw/main/265_bug_input_video.mov
For context the input video was generated as such:
% ffmpeg -f lavfi \ -i testsrc=size=1280x720:duration=50 \ -vf "drawtext=text='%{n}':fontsize=72:x=(w-text_w)/2:y=(h-text_h)/2:fontcolor=white" \ -c:v libx264 -preset ultrafast \ 265_bug_input_video.mov
Then transcode to x265
% ffmpeg -i 265_bug_input_video.mov -c:v libx265 -tag:v hvc1 \ 265_bug_frozen_frames.mov
Open the transcoded video and step through it frame by frame. At some point you will see that a sequence of frames is repeated. Unfortunately it's in a different time every time, but seems to be in the first 15 seconds consistently.
Here is a sample output video: https://github.com/yurigorokhov/ffmpeg_bug/raw/main/265_bug_frozen_frames.mov
It is frozen in the frame range 245 -> 250