I would like to use OpenGL for image processing. Can OpenGL deal with file formats like TIFF and BMP or do I need to decompress those images in the raw pixel format?
Can OpenGL read images stored in data structures other than a [x] by [y] by  array?
OpenGL doesn’t handle any file formats. That is not its purpose. You must load and decode the files yourself, if decoding is necessary. Note that some OpenGL implementations do support particular compression formats natively, but you still have to load the file and pass the data to OpenGL or an extension thereof.
And yes, the image data you pass to OpenGL can be in one of many different data formats. The Red Book spells out those details.
[This message has been edited by DFrey (edited 04-30-2001).]