A variety of options are available to modify images prior to viewing. These options include clipping, dithering, depth reduction, zoom (either X or Y axis independently or both at once), brightening or darkening, and image merging. When applicable, these options are done automatically (eg a color image to be displayed on a monochrome screen will be dithered automatically).
Xloadimage is only distributed in source form, and may be obtained by anonymous ftp from ftp.x.org in /R5contrib/xloadimage.4.1.tar.gz.
Xloadimage is covered under a modified version of the MIT X Consortium copyright with all of these functions, thereby allowing full freedom with the code so long as the copyright notices remain intact. All contributions have similar notices.
Commercial sites are welcome to use the code even without special permission, licensing or royalty fees. I'm very happy to hear of this stuff going toward real products (it's in several that I am aware of) so I appreciate hearing of any use of some or all of the code in other applications. If you tell me you're using it I'm much more likely to keep you informed about new versions as well, so it works out well all around. Xloadimage does not require any form of licensing or royalty payment to use in a commercial product, but the MIT copyright does require mention of the copyright notice in accompanying documentation; xloadimage has several copyrights that may need inclusion. It's unlikely that I would ever prosecute someone for neglecting to follow the terms of the copyright, but your lawyers may disagree.