[FFmpeg-soc] [rfc] dither and rgb565 / rgb 555

[Keiji Costantini]

the generator seems working for rgb32 & rgb24, because the functions 
that calls those table calls them in the way expected.

Regarding rgb16 (aka rgb565), the function calculate the table position 
depending dither variables, and that causes segfaults.

Should I then reposition the table elements where that function expects 
them (es. using the same dithering values to nullify them) or there is 
another method?

In my generator I didn't use inv_tables or coefficients because I didn't 
see how them fit in the conversion. Expecially the coefficients found in 
the context.

Is there anything I missed?
-- 
Keiji Costantini