[Openchrome-users] Video overlay behind window

[István Váradi]

Hi,

I have been developing a DVD player and digital video recorder
application, originally for the DXR3 MPEG-2 decoder board, but I
ported it to the CLE266 a few years ago. At that time I wrote my own
(mostly) user-space driver for the CLE266 based on various sources
available on the Internet. (You can see the project and download the
source code at http://dxr3player.sourceforge.net. The CLE266 and the
digital video recorder stuff is not "officially" supported by me, but
the source code is there.)

In this application I provide OSD by drawing into the main framebuffer
and putting the video overlay *behind* the framebuffer. I.e. I don't
use the subpicture support for OSD, that is reserved for subtitles
only. Transparency and semi-transparency is provided by using the
alpha channel.

I am considering to use X (or perhaps the Openchrome driver directly)
instead of my own driver, so that I could support newer boards more
easily. However, I don't know how the above OSD support could be
realized with X and/or the Openchrome driver. Is it possible at all?
If so, how?

Any help is appreciated.

Thanks,

Istvan