[MPlayer-dev-eng] Important Apple YUV explanations in a nut shell

[Romain Dolbeau]

Shan <sweber at slingshot.co.nz> wrote:

> The native 8-bit mac classic capture and rendering format is in the 
> order: Y0CbY1Cr
> 
> With no clamping on values and two's complement to show balance for 
> color differenced values
> 
> Which I like to call "Packed image Y' signed CbCr 4:2:2" - types "yuv2"
> "yuvu"

That would be kComponentVideoSigned. mplayer doesn't know how to
generate that, I believe.

> The native 8-bit Microsoft rendering format is in the order: Y0CbY1Cr
> 
> With CCIR clamping on values and no two's complement to show balance 
> for color differenced values
> 
> Which I like to call "Packed CCIR Y' unsigned CbCr 4:2:2" - types 
> "YUY2" "yuvs"

That would be kComponentVideoUnsigned.

(yes the u is for signed and the s for unsigned ...)

> The native 8-bit mac OSX rendering and Microsoft format is in the 
> order: CbY0CrY1
> 
> With CCIR clamping on values and no two's complement to show balance 
> for color differenced values
> 
> Which I like to call "Packed CCIR unsigned CbCr Y' 4:2:2" - types 
> "2vuy" "UYVY"

That would be k422YpCbCr8CodecType.

Unfortunately, all the above are translated, first in mplayer, then by
MacOSX. Without a scale matrix it seems they're translated to a YUV
format, and with they go all the way to RGB and RGB scaling :-(

I must be missing something, or maybe it's using Carbon instead of
Cocoa.

-- 
Romain Dolbeau