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ShowScan/HD compression



Jim Lindelien wrote:
> If one assumes 8kx8k resolution, at 12-bit or better color depth in R,G,& B,
> at 74 frames/sec, ShowScan works out to (give or take), 21 gigabytes per
> second. 
> 

>Herb Taylor wrote:
>   Interesting and sobering calculation. On the other hand, if we tile
>that surface up into 32 2kx1k channels and encode each to 15mb/s (i.e.
>using Gary Demos layered MPEG2) we have "only" 480mb/s. For a "Personal
>Omnitheatre" experience to the home you would need to use 16  6Mhz
>channels (QAM 64 = 30mb/s per channel). Although such a system with 32
>HD equivalent decoders and tiling hardware will be too costly for the
>home consumer for quite a few more years one could see the special venue
>theatre or corporate campus with such a system fairly soon. As for home
>entertainment a system delivering 2-4 channels to a mini dome should be
>possible in the next few years. One could deliver a served film ride
>experience to the home via cable. That's my dream...

My original point was to emphasize eye-brain bandwidth, since clearly one is
able to sense the ShowScan difference.  Present compression techniques are
useful in that they can turn financially unrealistic projects into do-able
things, but at a cost to the image.  Certainly all fluid images contain
highly redundant information which sufficiently advanced technology should
be be to transparently remove.  For me, the MPEG schemas aren't it, because
the "financially realistic" Mbps knob-setting is too low. I don't personally
like it when the image turns into little tiles every time something moves
through it, and when it fades to black.  Anybody else feel this way?  Is it
an oxymoron to talk of "compressed high definition"?  Someone should do a
review over the past century of the rate of increase in communications
bandwidth available to consumers, and extrapolate into the future.  I'd like
to know I can just wait for the 21 gigabytes! ;-)

-Jim




----------------------------------------------------------------------
Real-time and high-performance hardware and software design since 1981
Jim Lindelien                           (Email to: jiml at timelogic.com)     
Time Logic, Inc., 880 Northwood, Suite 1, Incline Village, NV 89451
Phone 702-833-0200 x11 Fax 702-833-1222  Web http://www.timelogic.com

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