[FFmpeg-devel] The v4l2 demuxer and the use of libv4l2

Carl Eugen Hoyos cehoyos at ag.or.at
Sun Dec 30 14:48:10 CET 2012

Stephan Hilb <stephan <at> ecshi.net> writes:

> To my surprise I noticed just now that when ffmpeg is build with the
> "--enable-libv4l2" flag (and thereby using libv4l2 as an additional
> layer between ffmpeg and the kernel api) my camera doesn't work as
> expected and the cpia decoder isn't used (libv4l2 does the conversion
> instead).
> Now this leads me to the question why the libv4l2 userspace library is
> used anyways when there is an appropriate decoder available for the
> format (cpia in my case).

Users requested this repeatedly (although I cannot remember 
a good reason). It would mean additional programming effort 
to make it configurable at runtime.
Imo, just concentrate on the (default) --disable-libv4l2 
case, if possible do not completely break --enable-libv4l2.

Working on v4l2 is very welcome!

Carl Eugen

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