JBIG

File Format
Name	JBIG
Ontology	Electronic File Formats Graphics JBIG
Extension(s)	.jbg .jbig
Released	1993

Overview

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 presumably 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.

See also

• JBIG2

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.

External Links

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