[FFmpeg-user] Understanding Latency Delays in FFmpeg
Carl Eugen Hoyos
cehoyos at ag.or.at
Sat Sep 26 10:02:22 CEST 2015
Michael Casadevall <mcasadevall <at> ubuntu.com> writes:
> I'm currently working on building a low-latency screen
> capture application using FFmpeg, and VP8.
I wonder if VP8 may be the encoder with the
highest latency available.
> 3. x11grab uses the MIT-SHM extension to grab the
> raw RGB data from X11. This has to be transcoded
> to YUV for almost any encoder to work (x264rgb
> appears to be an exception).
There should be multiple encoders encoding rgb, the
may not be ideal to stream though.
> - Is it possible to get better performance from x11grab?
Please test x11grab with the following configure options
(and report back):
--enable-gpl --enable-x11grab --disable-libxcb
> As best I can tell, most of the latency appears to
> becoming from having to transcode from RGB to YUV
> formats internally within FFmpeg
I believe it is possible to make the scaling filter
multithreaded (using slices) but it wasn't done yet.
More information about the ffmpeg-user