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Video Image Compression

The development of digital video technology has made it possible to use digital
video compression for a variety of telecommunications applications.
Standardization of compression algorithms for video was first initiated by CCITT
for teleconferencing and video telephony.

Multimedia standards for Video:

Requirements for full-motion Video Compression Applications using MPEG
standards can be symmetric or asymmetric. Symmetric applications are
applications that require essentially equal use of compression and decompression.
Asymmetric applications require frequent decompression.

Symmetric applications require on-line input devices such as video cameras,
scanners and microphones for digitized sound. In addition to video and audio
compression, this standards activity is concerned with a number of other Issues
concerned with playback of video clips and sound clips. The MPEG standard has
identified a number of such issues that have been addressed by the standards
activity. Let us review these Issues.

Random Access
The expectations generated for multimedia systems are the ability to playa sound
or video clip from any frame with that clip, irrespective of on what kind-of media
the information is stored

VCR paradigm
The VCR paradigm consists of the control functions typically found on a VCR
such as play, fast forward, rewind, search forward and rewind search.

Multiplexing Multiple Compressed Audio and Video Bit Streams
It is a special requirement retrieved from different storage centres on a network.
It may be received from different storage centres on a network. It may have to be
achieved in a smooth manner to avoid the appearance of a jumpy screen.