Cascading LZW algorithm with huffman coding: A variable to variable length compression algorithm
Two common schemes in data compression are fixed to variable length coding and variable to fixed length coding. Higher compression is expected from the more flexible scheme of variable to variable length coding. In such a scheme a compression dictionary is used to transfer variable length strings over the text alphabet into variable length strings over the coding alphabet. The compression is achieved due to matching longer more frequent text strings with shorter coding strings.
To obtain a variable to variable length coding we choose to cascade the LZW, variable to fixed, coding with the Huffman, fixed to variable, coding. In this work we consider the effective way of performing this cascading, to optimize the compression using limited time resources.
KeywordsCompression Ratio Compression Algorithm Length Code Code Word Huffman Code
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