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Compression Name CCITT T.6
Other names CCITT Group 4
Identifier(s) PUID:  x-cmp/15
Description Officially known as CCITT T.6, Group 4 is a compression algorithm developed by the International Telegraph and Telephone Consultative Committee as a development of the two-dimensional Group 3 standard for encoding and compressing 1-bit (monochrome) image data. It is faster, and offers compression rates which are typically double those of Group 3. Like Group 3, it is lossless and designed for 1-bit images. However, being designed as a storage rather than transmission format, it does not incorporate the error detection and correction functions of Group 3 compression. Group 4 compression is most commonly used in the TIFF file format.
Lossiness Lossless
Released 01 Jan 1989
Developed by International Telecommunication Union
Supported by
Documentation CCITT Blue Book, 1989, Volume VII, Fascicle VII.3: Terminal equipment and protocols for telematic services, recommendations T.0 - T.63
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