Minidjvu is a command line utility which encodes and decodes single page
black-and-white DjVu files, and can compress multiple pages, taking advantage
from similarities between pages.

Supported bitmap formats are PBM, Windows BMP, and TIFF (through libtiff).

Minidjvu is based on DjVuLibre, which is the primary DjVu support library.
Minidjvu is not going to support all DjVu functionality; the idea is rather to
take the black-and-white part (also called JB2) and experiment with it.