Data Compression


Survey Formats


Compression Methods

Data Formats

Run Length Encoding

General Principle

Control Characters

RLE for Image Data

Pixel Coding

Sequential Processing

Line Coding


End of Line Marker

Repetition of Lines

Lossy RLE





End of Line Marker

Image data are commonly structured line by line, i.e. for any processing the first line of a particular area has to be accessed. During run length encoding the correlation between coordinates and the corresponding position within a file is lost.

Several data formats provide a special marker that allows to identify the end or the beginning of a line even within already encoded data. This end of line marker is uniquely defined outside the common range of values. It can be detected by reading the data stream without decoding.

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RLE for Image Data Cross-Coding Repetition of Lines