cljl
CLJL (Common Lisp JPEG Library) can compress and decompress raster-images to/from the JPEG image file format.

CLJL was developed by Eugene Zaikonnikov with sponsorship by Kelly E. Murray. Is is hosted on common-lisp.net here .

Dave Watson: Note that this library is _NOT_ thread safe.

ASDF-install package (obsolete) http://www.common-lisp.net/project/mcclim/cl-jpeg.tar.gz