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In coding theory, especially in telecommunications, a self-synchronizing code〔US Federal Standard 1037C〕 is a uniquely decodable code in which the symbol stream formed by a portion of one code word, or by the overlapped portion of any two adjacent code words, is not a valid code word. Put another way, a set of strings (called "code words") over an alphabet is called a self-synchronizing code if for each string obtained by concatenating two code words, the substring starting at the second symbol and ending at the second-last symbol does not contain any code word as substring. Every self-synchronizing code is a prefix code, but not all prefix codes are self-synchronizing. Other terms for self-synchronizing code are synchronized code〔Berstel et al (2010) p. 137〕 or, ambiguously, comma-free code.〔Berstel & Perrin (1985) p. 377〕 A self-synchronizing code permits the proper framing of transmitted code words provided that no uncorrected errors occur in the symbol stream; external synchronization is not required. Self-synchronizing codes also allow recovery from uncorrected errors in the stream; with most prefix codes, an uncorrected error in a single bit may propagate errors further in the stream and make the subsequent data corrupted. Importance of self-synchronizing codes is not limited to data transmission. Self-synchronization also facilitates some cases of data recovery, for example of a digitally encoded text. ==Synchronizing word== A code over an alphabet has a ''synchronizing word'' (aka "syncword") in if :.〔 A prefix code is synchronized if and only if it has a synchronizing word.〔Berstel et al (2010) p. 138〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Self-synchronizing code」の詳細全文を読む スポンサード リンク
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