Andrew:
There is no PC version of NIH-Image.
If you download the FAQ for NIH-Image from
zippy.nimh.nih.gov
Username: Anonymous
Password: yourEmailAddress
Directory: pub
Folder: nih-image
it talks about IBM alternatives for image processing. I believe there is also a
blurb on the subject in the NIH-Image manual available at the same site in the
"Docs" folder.