[MPlayer-dev-eng] alpha compositing over video with gpu acceleration

[Chris Morgan]

Hello.

I'm working on a proof of concept for showing an alpha blended osd
that could be modified at runtime on top of hd video playback. The
target is an intel atom system, possibly the d510.

I've considered using a window manager and putting the osd window
above the video window, this only seems to provide a single alpha
value for the osd window, so to make a semi-transparent background I'd
also end up with semi-transparent text.

I've done a bit of reading and came across vf_overlay. I'm aware that
it hasn't made it into mplayer proper yet and wanted to find out what
possible paths are possible here.

Does using vf_overlay preclude acceleration with vaapi/vadpu or simply
a performance hit?

I've heard mention of an alternate path for vf_overlay development in
terms of a different design and location in mplayer. Is this work
beyond the design phase?

I'm sorry if my questions seem off-topic for the developers list. I've
been in open source development for some time and if there is a path
forward that doesn't involve a million hours of work I'd be interested
in helping out to move it forward.

Chris