[FFmpeg-devel] [patch] enable yuva420p as overlay background

[Tim Nicholson]

On 26/11/12 23:57, Stefano Sabatini wrote:
> On date Sunday 2012-11-25 15:24:29 +0000, Mark Himsley encoded:
>> Same calculation as for RGBA etc to create unpremultiplied output.
> 
>> Useful for creating an intermediate "ME bank", in vision mixer
>> (switcher) terminology.
> 
> What do you mean by "ME bank"?
> 

I thought that would cause confusion... In a vision mixer which can
blend (mix overlay etc etc) two streams together, one of the streams may
itself contain such a blend, so that the final result contains 3
streams, blended in a cascaded manner.

The "upstream" blending is usually done in a vision mixer on what is
referred to as an "ME bank" (Mix /Effects). Big units may well have
several of these to enable multiple cascading.

A________  ME bank
         \______________
B________/              \   Main
                         \________
C________________________/




>> [..]
> 
> LGTM.
> 


-- 
Tim