DATA COMPRESSION TECHNOLOGY

Items such as CD players, digital audio tape, digital TV, computer hard-disk drives and many other applications rely on data compression algorithms, the product of research funded, in part, by NSF more as a curiosity and first used for satellite transmission.

In the early 1960s, researchers Reed and Solomon introduced ideas that form the core of current error-correcting techniques for everything from computers used with Voyager II satellite transmission to CD players.

Reed-Solomon codes are used for error correction in high-speed, high-density information processing.They are particularly good at dealing with "bursts" of errors.

Current use of these codes in CD technology is able to cope with error bursts of up to 4,000 consecutive bytes. Despite advantages, Reed-Solomon codes did not go into use immediately, because technology had to make advances. As technology caught up, many researchers began to work on implementing the codes.

University of California-Berkeley Professor Elwyn Berlekamp invented an algorithm that decoded the Reed-Solomon code and is the basis for decoding CD players. Compact discs use a version called cross-interleaved Reed-Solomon code, or CIRC.

Thirty years after their invention, the wide application of these codes has settled the question of their practicality and significance.