> > > 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. > > for 720p, subsampled to 4:2:0, 30fps: > 1280*720*2*30 = 53MByte/s
30 fps, not 60? Hopefully the fans of fast action will not be too mad over losing half the frames. So 1080i would be 1920*1080*2*30 = 124416000 = 125 MB/s = 119 MiB/s ? 124416000 * 8 = 995328000 bps That would be *very* difficult, probably impossible, to squeeze into a 1 Gbps pipe when you consider protocol overhead and such. > But actualy, you do not want to have video and audio output > on different machines connected over a slow network. The > delay becomes unpredictable and thus A-V synchronisation > is very bad. The X-server-box would have audio output. > > > 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. > > Expect to do that already now. MPlayer currently supports something > in the range of 200 different video codecs. libavcodec (the main > decoding library) commes currently with over 50 codec schemes, most of > them decoding more than one video codec. > Even if you want to limit yourself to the most used codecs you'll > get way more than you can support (i'd say something in the range > of 20 codecs). 200? Obviously it is far too easy to create your own codec. So let's compile a *short* list of the most useful codecs. mpeg 1/2/4 covers OTA and DVD and more IIRC Blu-Ray and HD-DVD use H.264 ? _______________________________________________ Open-graphics mailing list [email protected] http://lists.duskglow.com/mailman/listinfo/open-graphics List service provided by Duskglow Consulting, LLC (www.duskglow.com)
