JBIG

JBIG, also called JBIG1, is a lossless image compression algorithm and data format. The compression algorithm is based on arithmetic coding.

It is named after the organization which developed the format, Joint Bi-level Image experts Group.

JBIG is primarily used for bi-level images, but a JBIG codestream may contain multiple image "planes", which can be combined and interpreted as a grayscale image, or even a full color image.

JBIG works best when contained in some other file format. It can be stored in a file by itself, but that's risky, because the specification does not fully describe how to interpret the colors of the pixels. Reasonably-portable JBIG files are probably limited to bi-level and grayscale, and even then, don't be surprised if black and white get reversed.

Specifications

 * ITU-T Rec. T.82
 * ITU-T Rec. T.85 - Defines a subformat ("application profile") of JBIG.

Software

 * JBIG-KIT: A free C library
 * Netpbm - Uses a fork of JBIG-KIT.
 * ImageMagick

Sample files

 * https://telparia.com/fileFormatSamples/image/jbig/

Links

 * Wikipedia article
 * JBIG Homepage
 * JBIG Compression, from the Encyclopedia of Graphics File Formats