🚀 go-pugleaf

The following excerpt is from an article published on page
193, of PC MAGAZINE (January 31, 1989 Vol.8 No. 2). It has
many relevant points to subjects raised recently on the net -
mainly by implication that is.

(* -clarified at conclusion of this posting)
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          GE/RCA's DVI (Digital Video Interactive) technology
     directly addresses the bandwidth* problem. DVI uses delta and
     ADPCM* techniques, but its special forte is _Asymmetric_
     compression.  During the off-line preparation of a CD-ROM,
     the DVI process requires about three seconds of a powerful
     Meiko parallel-processing number-cruncher's time to compress
     each image frame at a staggering 120:1 ratio. But at
     playback, everything happens in real time: the powerful (12.5
     MIPS)* DVI chip set decompresses the image on the fly. The
     result: up to 72 minutes of full-screen, full-motion digital
     video (at a resolution of 256 by 240, with 16 million
     colors)* can squeeze onto a single standard CD-ROM.
          Fully digital video can be manipulated with ease -as the
     gasps of amazement at DVI demonstrations attest. Truly
     interactive TV sets lets you use a joystick to "look around"
     in any direction and "walk" at a speed you control.
     "Synthetic" video lets you overlay photographic textures and
     colors onto 3-D models of rooms and furniture. And DVI
     offers much more, including on-the-fly "exact reproduction"
     compression for high-resolution graphics and a 10-frame-per-
     second "edit level" mode for video development.
          DVI's major obvious drawback is that you need a DVI
     system to decode its disks. DVI is now available only as a
     three-board set for standard 16-bit PC AT slots: one for
     video, one for audio, and one to control a CD-ROM drive and
     joystick. Currently in beta testing, the boardset is expected
     to roll out to the public for $7,000 to $10,000 (depending on
     the configuration) in the first quarter [of] 1989. Development
     software and support are likely to run another $15,000. It's
     fair to guess that developers of high-end interactive video
     applications will be major DVI pioneers. But increasing
     integration could bring prices down fast.
                                                   -Stephen Manes
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some clarifications:

*Bandwidth problem -CD-ROM's slow data transfer rate (~150
                    KiloBytes per second)

*ADPCM -probably Analog to Digital, Pulse Code Modulation

*MIPS  -Million Instructions Per Second

*256X240 is somewhat less than the broadcast NTSC maximum
resolution of 336 (Horiz) by 484 (Vert) lines. However,
much vertical detail is lost to the psychovisual effects of
TV. NTSC analog resolution specifics tend to be vague,
whereas digital parameters are precise. As well, DVI probably
has less than 30 decompressed frames per second for the given
resolution.

 
-C. Fogg