In the mid 1980s joint work by the members of the ITU-T (International Telecommunication Union) and the ISO (International Standards Organisation) led to standardisation for the compression of grey scale and colour still images. This effort was then known as JPEG: the Joint Photographic Experts Group. As is apparent, the word joint refers to the collaboration between the ITU-T and ISO. The JPEG encoder is capable of coding full colour images at an average compression ratio of 15 : 1 for subjectively transparent quality. Its design meets special constraints, which make the standard very flexible. For example, the JPEG encoder is parametrisable, so that the desired compression/quality trade-offs can be determined based on the application or the wishes of the user.
Coding of still pictures (JPEG and JPEG2000), Page 1 of 2
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