This web site was copied prior to January 20, 2005. It is now a Federal record managed by the National Archives and Records Administration. External links, forms, and search boxes may not function within this collection. Learn more.   [hide]
image- CD with binary code projection

Click on the arrows below to view the answers

What was the first use of data compression algorithms?

blue arrow

What are Reed-Solomon codes used for?

green arrow

What version of the code do CD players use?

purple arrow
 

 

 

 

 

Return to questions

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.



 

 

Return to top

home
nifty50
history
partners