Path: utzoo!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!uwm.edu!psuvax1!psuvm!rmc100
From: RMC100@psuvm.psu.edu (Randy Carraghan)
Newsgroups: comp.misc
Subject: Information Density of Sight and Sound
Message-ID: <90057.153351RMC100@psuvm.psu.edu>
Date: 26 Feb 90 20:33:51 GMT
Organization: Penn State University
Lines: 23

I just finished downloading some GIF files and noticed that the simplest
images, the cartoons, required about 10K for a single frame.  Assuming
we play the cartoon at 20 frames per second, approximately 330 megabytes
of disk space would be required to store a 30 minute cartoon.  This would
require, of course, that the computer be able to read the images off the
drive and display the images quickly enough to simulate an animated cartoon,
which is far from being possible on my IBM-PC AT.  The full-screen, color
images used on the order of 200K bytes of disk space for a single frame,
and these images used only 256 colors total.  Even using CDs, you'd only be
able to store a minute or so of animation.  Now if you were to implement some
sort of compression routine, you'd be able to increase the number of frames
you could store, but the playback speed would become slower than it already
is.  How is it that two hour movies are stored on a single video disk?
(Granted, video disks are larger than standard CDs, but the ration wouldn't
account for the 100-fold storage difference).  What kind of hardware
(computer and disk) capabilities would be needed to process video (or just
sound) at real time speed?  Another way of asking this is, how many bytes
per second would need to be processed (read in, transformed, displayed) for
various media types (simple cartoon, b/w, color, AM/FM/CD quality sound only).

Thanks for any info!

Randy Carraghan (rmc100@psuvm.psu.edu)