Acronym for Joint Photographic Experts Group.
A set of image FileFormats well suited for natural images. Standard JPEG uses lossy compression (Discrete Cosine Transform and quantisation) to significantly reduce file size while maintaining an acceptable image quality. JBIG is a specialization of JPEG for bi-level images (ie black and white). JPEG2000 is a newer, better format using wavelet compression -- which is Patent encumbered, so you're unlikely to see it implemented in OpenSource software.
JPEG image files commonly have the FileExtension .jpg or .jpeg, but rarely .jpe also occurs.
The "Joint" in the name refers to the fact that the standard is a joint effort between ISO and ITU-T. Like many ISO standards, you have to pay to get a copy of it.
See also:
6 pages link to JPEG:
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