JBIG is an acronym for 'Joint Bi-level Image Experts Group'. This is a group
of experts nominated by national standards bodies and major companies to work
to produce standards for bi-level image coding.
The JBIG group has developed IS 11544 (ITU-T T.82) standard
for the lossless compression of a bi-level image. It can also be used for
coding grayscale and color images with limited numbers of bits per pixel.
It can be thought to be similar to Group 3 or Group 4 fax, offering between
20% and 80% improvement in compression over these methods. JBIG compression
averages about a 20:1 over the original uncompressed image.