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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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Algorithm Encoding
create table providing frequencies
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sort symbols according to frequency
in descending order
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start with the entire table
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division:
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seek pointer to the first and
last symbol ot the segment
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divide the segment into two parts, both
nearly equal in sum of frequencies
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add a binary 0 to the code words of the
upper part and a 1 to the lower part
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search for the next segment containing
more than two symols and repeat division
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coding of the origination data according to
to code words in the table
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The decoding process follows the general algorithm for interpretation of binary code trees.
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