[FFmpeg-devel] [PATCH] vf_overlay: add support to RGBA packed input and output

[Stefano Sabatini]

On date Saturday 2011-10-29 16:33:59 +0100, Mark Himsley encoded:
> On 29/10/2011 03:10, Michael Niedermayer wrote:
> >On Sat, Oct 29, 2011 at 12:56:15AM +0200, Stefano Sabatini wrote:
> >>On date Thursday 2011-10-27 01:01:40 +0200, Michael Niedermayer encoded:
[...]
> In the future I plan to propose further patches to the overlay filter.
> The overlay filter needs to accept more pixel formats, most
> important to me are yuv422 and yuva422. And the YUV overlay section
> needs to be able to output non-premultiplied fill and calculated key
> channels too.

One of the problems is that we need to force main and overlay formats
to be the same. A possible way would be to set the format as a
parameter (e.g. overlay=x:y:format=yuva422p), in this case you have:
main=yuv422p
overlay=yuva422p

or we'll need to perform all the kind of sub/upsampling which really
don't belong to lavfi, and we only provide support to yuva420p, so at
first we should extend swscale to support more YUV alpha formats.
-- 
FFmpeg = Faithless and Friendly Mysterious Ponderous Earthshaking Gymnast