JBIG2

JBIG2 is a patent-encumbered standard for lossy and lossless compression of bi-level images.

A JBIG2 codestream may appear in a file by itself, or embedded in another format such as PDF.

Identification
JBIG2 files begin with an 8-byte signature:.

Specifications

 * ITU-T Rec. T.88

Software

 * jbig2dec
 * Konvertor

Links

 * Wikipedia article
 * Xerox scanners/photocopiers randomly alter numbers in scanned documents