[FFmpeg-user] ffmpeg slowly get out of sync

[Carl Eugen Hoyos]

2016-11-16 12:59 GMT+01:00 Luo Xin <luoxin123 at sina.com>:

> - output hls segments

Don't you agree that the issue would be easier to reproduce
with file output?

> ffmpeg version n3.1.3-1-gea9ca2f Copyright (c) 2000-2016 the FFmpeg

Note that this is old and unsupported.
On this mailing list, only current FFmpeg git head is supported,
I suspect there are Ubuntu support resources.

> Input #0, alsa, from 'hw:3':
>   Duration: N/A, start: 1479202954.916662

> Input #1, video4linux2,v4l2, from '/dev/video2':
>   Duration: N/A, start: 31.451263

This cannot work, the start times have to be similar.
Try -timestamps abs (or mono2abs) for the v4l2 input.

And please remove "-r 25" from your command line,
it does not do what you want, there is a "-framerate"
option for v4l2 input.

Carl Eugen