Accelerated subtitle rendering in 1.0

[Tim-Philipp Müller]

On Mon, 2012-08-06 at 22:41 +0200, Arnaud Vrac wrote:

> I did do that, as I said I removed the queues from the pipeline for
> simplicity. However it still stalls. I guess this won't happen if I
> have a single element for rendering.

Ah, sorry, missed that bit.

Your overlay element would probably need to generate a GAP event if an
input buffer does not have an overlay composition attached. This should
then also preroll the overlay sink. Alternatively, you can set the
overlay sink to async=false.


> ARGB is fine, however I still need to blend all the rectangles in a
> single transparent framebuffer, meaning that I have to use a library
> like pixman. It's ok, but it wouldn't add much code to get a
> gst_video_overlay_composition_render function that does not blend with
> the destination surface pixels. I think it would be a good addition to
> the public API.

Ah, right that would be

http://cgit.freedesktop.org/gstreamer/gst-plugins-base/tree/docs/design/draft-subtitle-overlays.txt#n423

then I guess ?

Feel free to provide a patch for that :)

Cheers
 -Tim