
free library without patents:
http://www.ijg.org

helpers:
http://apodeline.free.fr/DOC/libjpeg/libjpeg.html
http://www.jpegcameras.com/


http://en.wikipedia.org/wiki/JPEG

Official standard (with patents)
http://www.w3.org/Graphics/JPEG/itu-t81.pdf
