Run-length encoding

Run-length encoding (RLE) is a simple kind of data compression, in which a run of consecutive equal data values is replaced by a code indicating the run length and the data value.

RLE can be effective for some types of data, or as part of a more sophisticated algorithm, but by itself it is a poor general purpose compression algorithm.

Formats which can use some form of RLE include
 * TIFF (compression type 32773: PackBits)
 * BMP (compression types RLE4 and RLE8)
 * TGA
 * PCX