[vlc-devel] ffmpeg this and that (was Re: [PATCH] Remove chroma conversions already handled by swscale)

[Rémi Denis-Courmont]

On Mon, 28 Jun 2010 23:01:40 +0200, Rafaël Carré <rafael.carre at gmail.com>
wrote:
> Require libswscale >= 0.5.0 in configure.ac
> Remaining chromas unknown to libswscale:
>     - YVYU : Packed YUV 4:2:2, Y:V:Y:U
>     - IUYV : ?
>     - CYUV : 10-bit 4:2:2 Component YCbCr
>     - Y211 : Packed YUV 2:1:1, Y:U:Y:V
> Should be possible to add to libswscale chroma converter:
>     - YUVA : Palettized RGB with palette element R:G:B
> 
> Briefly tested against a couple of movies, MMX and SSE2 modules still
> build I made no speed comparison

The whole point of these plugins is, or at least was, to be as fast as
possible. They may not be so relevant anymore considering that:
1/ most decoded video signals are I420 or YV12, and
2/ most (commonly used) video outputs support hardware YUV [1].

But generally, there is a LOT of stuff we COULD remove if we relied upon
FFmpeg, chromas, scalers, codecs, demuxers, muxers, accesses... And someone
will surely write a VLC plugin for libavfilter sooner or later.
That does not mean it is a good (or bad) idea. That brings the more
disturbing question whether there remains anything of (Lib)VLC if FFmpeg
does everything.

[1] Or not. My ATI Xorg driver is much less stable than the plain VESA
driver. The latter obviously lacks XVideo.

-- 
Rémi Denis-Courmont
http://www.remlab.net
http://fi.linkedin.com/in/remidenis