Opened 8 years ago
Last modified 2 years ago
#4703 new defect
Audio cut off in screencast
|Reported by:||Kai Hendry||Owned by:|
|Cc:||Neven Sajko||Blocked By:|
|Blocking:||Reproduced by developer:||no|
|Analyzed by developer:||no|
Summary of the bug: Last second or two of audio is cut off during a screencast: http://s.natalian.org/2015-07-08/cutoff.mp4
How to reproduce:
% ffmpeg -v warning -f x11grab -video_size 1920x1080 -i :0 -f alsa -i pulse -acodec pcm_s16le -c:v libx264 /tmp/cutoff.mkv &>> /tmp/r2d2.log & ffmpeg version 2.7.1 built on Archlinux
When i kill ffmpeg during a screencast, my voice is cut off http://s.natalian.org/2015-07-08/cutoff.mp4
Here is the log http://s.natalian.org/2015-07-08/cutoff.txt
Regular kill and
kill -INT $pid has the same problem.
Source of my script: https://github.com/kaihendry/recordmydesktop2.0/blob/master/x11capture
Change History (10)
comment:1 by , 8 years ago
comment:2 by , 8 years ago
First steps to make this a valid ticket are to test current FFmpeg git head and provide the command line that allows to reproduce the issue together with the complete, uncut console output here on the bug tracker.
Is the issue also reproducible if you press "q"?
comment:3 by , 8 years ago
I just built from git head ffmpeg version N-73452-g80e4238 and the problem exists. http://s.natalian.org/2015-07-08/1to5.mkv
Yes, I pressed "q" to stop the video after saying five.
comment:4 by , 8 years ago
Does it also happens if you only record audio without video?
comment:5 by , 8 years ago
It does not happen when I record just with audio: http://s.natalian.org/2015-07-09/sound-only.mkv with
ffmpeg -f pulse -i default sound-only.mkv.
I believe this to be a fairly recent (last two months?) regression, but I don't have time to bisect atm.
comment:6 by , 8 years ago
This is happening to me as well. The last few seconds of my voice get cut off. Arch Linux as well.
comment:7 by , 7 years ago
Happens also on Fedora 23, as reported by rhn on irc.
comment:8 by , 6 years ago
Same on Arch x86_64 Linux 4.12.8.
comment:9 by , 2 years ago
comment:10 by , 2 years ago
There's more info that seems like it could be useful if someone tries to tackle this bug here: https://trac.ffmpeg.org/ticket/9199
In that case the last 15 seconds of audio are cut off (instead of just the last two), and pulseaudio isn't used, just ALSA directly.
There's also a large ffreport.log attached to that bug report (which is now closed as a duplicate).
I can confirm the bug with the pulse audio line from https://trac.ffmpeg.org/wiki/Capture/Desktop
ffmpeg -video_size 1024x768 -framerate 25 -f x11grab -i :0.0+100,200 -f pulse -ac 2 -i default output.mkv