[vlc-devel] Crystal HD for 1080i MPEG2 and closed captions on low-end system

[Rémi Denis-Courmont]

Le jeudi 9 juin 2011 20:14:29 Jean-Baptiste Kempf, vous avez écrit :
> Although converting from NV12 to something cool should be easier than
> from the current one.

The conversion to I420 or even YUYV is easy. But I don't have a clear view of 
which chroma conversions really are needed and which are not, before VLC 
"supports" a new chroma.

Currently (excluding swscale), we have:

* I420 or YV12
-> YUYV, YVYU, UYVY
-> CYUV
-> Y211
-> RGB8 in any order
-> RGB15 in any order
-> RGB16 in any order
-> RGB32in any order
Note: RGB24 not supported. IUYV stubbed.

* I422 or J422
-> I420, YV12
-> J420
-> YUVA (sic!)
-> YUYV, YVYU, UYVY
-> CYUV
-> Y211
Note: J<->I mixed conversions seem fake. IUYV stubbed.

* YUYV, YVYU, UYVY
-> I420
-> I422

* CYUV
-> I420
-> I422

* GREY
-> I420
-> YUYV

In particular, there are no ways to directly convert any packed YUV format to 
RGB if needed, unless I missed seemingly non-existent support for indirect 
chroma conversions. So it is totally unclear which chroma conversion besides 
the obvious I420, if any, NV12, and NV21, would require to work flawlessly.

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