Too late to edit: PCX is lossless, what we did was reduce the higher frequency bits in the images before using PCX in order to achieve a reasonable compression ratio, in effect making a lossy wrapper around PCX. It was a pretty crude way of making this work and JPEG was so much better that it is hard to believe we managed to sell our customers on the original version. I should see if I can dig up some of those old images, they're interesting historically.