[Open-graphics] Re: X-video-server

[Dieter]

> > > Do you (or anyone) have any thoughts on JRT's suggestion of using a
> > > DSP chip?  The decoder needs to handle the most common formats,
> > > mpeg at the very least, to avoid transcoding.  Transcoding takes a
> > > lot of CPU, and Theora is lossy.
> >
> > True. What would be nice would be a CPU with a built-in DSP, so that the
> > CPU can handle the network stuff and OSD and so on, and the DSP could
> > do the heavy-duty decoding work.

Timothy> How "realtime" does this need to be?  Can we not implement the
Timothy> networking stuff on the DSP?

Realtime requirements probably vary with Ethernet chip?

Nick> Well, are we still thinking about having a 1000Mbit network, or does
Nick> 100Mbit offer enough bandwidth?

If HD mpeg2 is the worst case, then 100Mbit is plenty.

Timothy> I'm planning on implementing RGB <-> YUV conversation, at least.
Timothy> Rather than spending bunches of CPU time doing the matrix algebra, we
Timothy> can do it in hardware and save at least SOME converstion time.

IIRC, OGC will also do scaling.  Anything else it can offload?

Nvidia claims their GPU does 95% of the decode for mpeg2.  (page 9 of
the pdf from the other day.)  They claim to save 9 Watts decoding HD
on gforce7 vs on CPU.  (page 19)  I don't see a mention of what CPU
they used.

If OGC can't offload enough, are there HD mpeg decoder chips that we
could consider?  (e.g. documented)