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Data Compression
Criteria
Survey Formats
Basics
Compression Methods
Data Formats
Run Length Encoding
General Principle
Control Characters
RLE for Image Data
Implementations
MS-Windows .bmp RLE8
Encoded Mode
Absolute Mode
Marker
Example "B"
MS-Windows .bmp RLE4
Glossary
Index
Download
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Marker
Marker will be initiated by the value 0 immediately followed by the byte value 0, 1, or 2 identifying the three markers available: "End of Line", "End of Bitmap" and "Delta".
Coding scheme marker:

- End of Line (00 00)
- The end of line marker indicates that the next code will apply to a new line. For the rest of the current line no further information is available. The default background colour has to be assigned to remaining pixels.
- End of Bitmap (00 01)
- The end of bitmap marker indicates the end of encoded data. Remaining parts will take over the background colour.
- Delta (00 02)
- The delta marker indicates a jump relative to the current position. The two bytes following quantify an unsigned horizontal and vertical offset. The next code words will be applied to the new position; the part in between will get the background colour.
Examples:
encoded decoded
00 00 end of line
00 02 0A B0 Delta-X = 10 pixel
Delta-Y = 176 lines
00 01 end of bitmap
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