Title :
Redundancy of the Lempel-Ziv-Welch code
Author :
Savari, Serap A.
Author_Institution :
Bell Labs., Lucent Technol, Murray Hill, NJ, USA
Abstract :
The Lempel-Ziv codes are universal variable-to-fixed length codes that have become virtually standard in practical lossless data compression. For any given source output string from a Markov of unifilar source, we upper bound the difference between the number of binary digits needed by the Lempel-Ziv-Welch code (1977, 1978, 1984) to encode the string and the self-information of the string. We use this result to demonstrate that for unifilar, Markov sources, the redundancy of encoding the first n letters of the source output with LZW is O((ln n)-1), and we upper bound the exact form of convergence
Keywords :
Markov processes; convergence of numerical methods; data compression; source coding; variable length codes; Lempel-Ziv-Welch code redundancy; binary digits; convergence; encoding redundancy; lossless data compression; source coding; source output string; string self information; unifilar Markov sources; universal variable to fixed length codes; upper bound; Code standards; Concatenated codes; Convergence; Data compression; Decoding; Dictionaries; Encoding; Entropy; Steady-state; Upper bound;
Conference_Titel :
Data Compression Conference, 1997. DCC '97. Proceedings
Conference_Location :
Snowbird, UT
Print_ISBN :
0-8186-7761-9
DOI :
10.1109/DCC.1997.582011