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Desktop Video AGOCG Report

Compression Techniques

It seems that Parkinson's Law applies in all walks of life and hence messages expand to fill the available bandwidth. The obvious solution to the problem of the overloading of the communication links is the evolution of existing compression techniques. The best of today's compression techniques struggle with the challenge of squeezing a TV quality video signal through a 64 Kbps ISDN channel without discarding too much of the data and thereby producing a seriously degraded image.

As a result, desktop videoconferencing systems typically compromise by offering smaller windows (as tiny as 80 by 96 pixels), grainier colour (8 bits per pixel instead of 24 bits) and lower frame rates (5 frames per second or less under certain conditions). These trade-offs reduce the bit stream to manageable levels.

4.1.1 - Compression in Video for Windows
4.1.2 - Compression in QuickTime
4.1.3 - MPEG
4.1.4 - CCITT Standards
4.1.5 - CODECs for Desktop Videoconferencing

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