Self-Synchronizing Reversible Variable Length Codes
نویسندگان
چکیده
A reversible variable-length code (RVLC) is a code in which the bit stream formed by a portion of a codeword, or by the overlapped portion of two or more adjacent codewords, is not a valid codeword. A self-synchronizing RVLC allows for a sequence of codewords to be decoded either backwards or forwards without any external synchronization. In this article, we present an algorithm for constructing a self-synchronizing RVLC in which a codeword functions as a sync marker. The main idea is to replace a minimum forbidden word (MFW) of the codeword stream with a codeword. Then the MFW plays as a sync marker. Moreover, a lower bound of probability that at least one such a resynchronization codeword appears in a constant interval is obtained. A sync string of RVLC is discussed as well.
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