🚀 go-pugleaf

In article <1gr5taINNrr4@fido.asd.sgi.com> grege@chopin.asd.sgi.com (Greg Estes) writes:
>In article <1338@taniwha.UUCP>, paul@taniwha.UUCP (Paul Campbell) writes:
>|> In article <SUHONEN.92Dec7104750@jalka.jyu.fi> suhonen@jalka.jyu.fi (Timo Suhonen) writes:

>|> >I'm looking for a way to pack digitized video frames to hard disk and
>|> >further to show those packed files on screen (several pictures in second).
>|> 
>|> Buy a SuperMac 'Digital Film' board for a Macintosh (and get a fast CPU and
>
>As an aside, an SGI Crimson (not a 310) VGX can run ~30FPS full resolution
>uncompressed video from memory. So, if you can store the images in memory
>instead of a disk, upgrading from a 310GTX to a Crimson/VGX may be a better
>use of your money than starting all over on the Mac and going the JPEG path.
>This would also allow you to take better advantage of your VideoLab board,
>since the VGX graphics would get you all sorts of fun things, like writing
>moving video into texture memory to map on objects, etc.

My point in recomending he look at a Mac solution is because the enabling 
technology isn't super-fast memory to screen transfer (many Mac accelerated
video cards support off-screen RAM arrays with very fast display rates too),
it's real time compression/decompression of the data as it's read off the disk.

The Digital Film card compresses JPEG frames in real time and the Mac writes
them to disk - memory based capture systems can only capture a few frames
at a time. On playback video data is read from disk and decompressed, again
playback is NOT limited by the number you can fit in memory. Remember an
uncompressed 24-bit 640x480 frame takes 2x640x480 bytes = ~1Mb, a second
takes 30Mb, a minute 1800Mb - when you are editing you throw away more raw
footage than you use ... memory's cheap but not that cheap.

By compressing the data 25x or so you can get the data rates down so that SCSI 
throughput is not a problem (although you probably still need to choose a 
fast disk or disk array with no remapped bad blocks).
-- 
Paul Campbell    UUCP: ..!mtxinu!taniwha!paul     AppleLink: CAMPBELL.P
Use up your Quayle jokes now while they're still good "Quayle for Pres. in '94"
     Q: Why is Marilyn Quayle like Marion Barry?
     A: They both suck a little dope.