Prefix code: Difference between revisions

Revision as of 01:09, 8 August 2005

Revision as of 08:34, 10 August 2005

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A '''prefix code''', also known as a '''prefix-free code''' or, '''comma-free code''' or '''instantaneous code''', is a [[code]] constructed so that any partial [[code word]], beginning at the start of a full code word but terminating prior to the end of that code word, is not itself a valid code word. In other words, for any given valid [[string (computer science)|string]] in the code, there is no shorter string in the code that is an initial substring of that string.

This property permits the proper [[framing]] of transmitted code words when (a) external [[synchronization]] is provided to identify the start of the first code word in a [[sequence]] of code words and (b) no uncorrected errors occur in the symbol stream.