> > What I don't know is how much CPU will be needed for video. I don't have > > a handle on how much the OGC GPU will do and how much the CPU will have to > > do. > > For the video case, the X server is only shuffling memory around. > No decoding or anything cpu intensive. But this means that it > needs to do a lot of I/O which is the bottle neck these days. > > Of course, you can offload some parts of the decoding with > XVmc, but that functionality is not widely spread and doesn't > work for all codecs.
This brings up the question of how much bandwidth do you need between the client and server if the client decodes? E.g. is Ethernet fast enough? If not, then we have to decode inside the X-video-server box. > It is another matter if you want to do decoding on this cpu too. > Then you cannot have enough power. Current schemes like h.264 need an > awfull lot of CPU time that you'd need something in the range > of 2GHz for any decent video resolution. The wikipedia H.264 page has a list of chips that decode H.264 in hardware. http://en.wikipedia.org/wiki/H.264/MPEG-4_AVC > Modern schemes that > are wavelet based exceede this by a factor of 10 or even more. And I suppose we can expect a new incompatible-wrench-in-the-gears every couple of years for quite awhile. So we'll have to make a list of what the X-video-server will decode, and anything incompatible will have to be transcoded on a general purpose computer. Which is a major PITA. _______________________________________________ Open-graphics mailing list [email protected] http://lists.duskglow.com/mailman/listinfo/open-graphics List service provided by Duskglow Consulting, LLC (www.duskglow.com)
