[extropy-chat] more moore

[J. Andrew Rogers]

Eugen Leitl wrote:
> No, coding/decoding resources are asymmetrical. H.264 realtime HDTV
> encoding in studio can take 100 k$ of hardware (if there is such a
thing yet,
> haven't looked), it doesn't matter. What matters is that how much
> hardware I need to replay H.264 off vanilla DVD or broadband video
stream at
> the user end, codec's/container's sundry bells and whistles included,
of course.


Back when I was actually working with H.264 codecs a year or two ago,
realtime decode of full 1920x1200 HDTV video (or somewhere in that rez
ballpark) was the domain of ASICs, but probably could be done native on
high-end PC processors with well-engineered codecs these days.  DVD
quality video was decodable by high-end PCs natively.  Decode is
definitely something you'd want to put in an ASIC for general consumer
consumption, though it is possible  in native mode.

H.264 HDTV encoding is another story altogether.  To do it in realtime
required an SGI ccNUMA refrigerator at the time.  Monsterous quantities
of crunch, and requiring serious amounts of usable RAM bandwidth.  If I
had to guess, a high-end dual processor PPC970 system dedicated to the
task might have enough DSP crunch to manage full-code video in realtime
with a highly optimized codec.  And that is probably sitting a bit too
close to the edge if you want maximize quality.


> Synthesizing fully immersive realtime 3d environments
> for each viewer will be required, then. With current CPU you'd be hard
> pressed to render immersive audio (not even with physical modelling)
aspect
> of that. 


This doesn't require more than 1000 DSP MIPs, and is old hat.  The
problem with immersive audio is that it interacts with the environment
it is played into when run through transducers, usually very poorly. 
With headphones, excellent immersive audio isn't a problem with current
processors.  Out of speakers, no amount of crunch will make up for the
fact that the gorgeously rendered audio environment is being filtered
through (and trashed by) a wildly unpredictable real environment.

But yeah, it isn't like there aren't gobs of applications that run far
slower than they probably should and many that just plain require more
crunch, <flog-dead-horse>though I would attribute a lot of that to basic
architectural issues.</flog-dead-horse>

j. andrew rogers