Stefan Lucke wrote: ...
Well, I noticed that when I once or twice had VDR+softdevice+text2skin
running, with a skin having animated stuff in it. If I understood right
(tm), the OSD is software-blended in the rendered video frame before
blitting it on the output layer.
But isn't "Blit" an accelerated function?
Fortunately, yes, if the hardware supports it. But I meant the blending before, that takes in certain situations (when a lot of OSD areas change, or text2skin uses animated images) too much CPU power which on a VDR system that _has_ to use softdevice is very valuable (even if not running at 100%, lower is better even if only to avoid heating problems in a htpc which everyone wants to be as quiet as possible).
Again, if I understood right (tm), in Ville's dfbmga mplayer video output driver, the OSD is drawn (on demand, that is, depending on command-line switches) as it's Matrox-specific, when we want TV-output, in the subpicture layer (usualy layer 3) and the video on the primary layer (CRTC2 if you set primary-layer=2), and the blending is done in hardware, by the graphics card. I hope this is not bulshit, what I just said... :-)
When my information is correct, the subpicturelayer is of depth 8bit with 4bit alpha and 4bit color information (-> 16 colors). So I think it's not much useful.
You might be right, I don't know, I'd suggest Ville should tell us here. If the situation is like this, I must admit, there's no fun having such an OSD in VDR.
Maybe I'm getting OT for this list, but am I assuming right, that softdevice takes whatever OSD data it receives from VDR as bitmap data and blends them pixel by pixel in the diplayed fram? Wouldn't then, for the DFB case (I know softdevice uses other output methods too) a DirectFB-like approach make more sense in that case, I mean using graphic primitives from DirectFB to draw the OSD, it's various image loading and displaying mechanisms, and even font rendering (FT2)? I know, that would be some sort of merged text2skin and video output device plugin for VDR just in a DirectFB "world". But I think that would be more efficient, I'm just thinking at the various demo screenshots on http://www.directfb.org with transparent windows moved with the mouse with almost zero CPU utilization...
Looks like a totally new plugin, right?
Lucian Muresan
