[x264-devel] Evaluating x264 -- first steps encoding greylevel images

[Eeri Kask]

>> In order to take x264 further beyond recreational deployments it
>> would be great if at least yuv444-planar input encoding would be
>> supported for color images, how much would it be different from
>> current yuv420 implementation?
>
> A lot of work.  It's currently a summer of code project idea:
> http://wiki.videolan.org/SoC_x264_2010 .  The primary problem is
> that we don't currently have a _decoder_ for yuv444 (except of
> course the reference).  Any useful implementation would also have
> to write support for libavcodec as well.


Under the assumption I understand it right, then x264.h contains

    #define X264_CSP_I444           0x0003  /* yuv 4:4:4 planar */

which I was referring to, thinking this is in fact "mathematically"
essentially the same planar format as X264_CSP_I420 but at full
spatial resolution.

Should this appear true, then the decoder should look much like the
one for I420 which we have already, even marginally simpler and
faster indeed (due to not having to deal with reduced chroma
resolution), so one would be tempted to just reuse the already
existing code (for this special case, for now)...   :-)


Greetings,

    Eeri Kask