Data Compression


Criteria

Survey Formats

Basics

Compression Methods

Shannon-Fano

Example

Algorithm

Step-by-Step

SF versus Huffman

Huffman

Lempel-Ziv (LZ)

Arithmetic Coding

Run Length Encoding

Burrows-Wheeler (BWT)

Implementations

Data Formats


Glossary

Index


Download


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Shannon-Fano Coding


At about 1960 Claude E. Shannon (MIT) and Robert M. Fano (Bell Laboratories) had developed a coding procedure to generate a binary code tree. The procedure evaluates the symbol's probability and assigns code words with a corresponding code length.


Compared to other methods the Shannon-Fano coding is easy to implement. In practical operation Shannon-Fano coding is not of larger importance. This is especially caused by the lower code efficiency in comparison to Huffman coding as demonstrated later.


Utilization of Shannon-Fano coding makes primarily sense if it is desired to apply a simple algorithm with high performance and minimum requirements for programming. An example is the compression method IMPLODE as specified e.g. in the ZIP format.


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