Data Compression


Criteria

Survey Formats

Basics

Compression Methods

Data Formats


Run Length Encoding

General Principle

Control Characters

8 Bit Control Character

in Original Data

alternating

by Repetitions

1 Bit RLE

7 Bit RLE

RLE for Image Data

Implementations


Glossary

Index


Download


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alternating Control Characters


A way out of the problem caused by control characters frequently appearing in original data is the definition of rules, according to which the control character changes at run-time. For example two alternating symbols can be defined.


Control Character:   # and *
     uncoded Data:   #####*****
       coded Data:   ##0*#3#*4

Beyond that a large variety of mechanisms is conceivable, so the control character's value could be incremented after each use. Another possibility is the use of the rarest symbol at run-time.


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8 Bit Control Character Control Characters within Original Data Repetitions as Control Characters