Solution will change as size and needs of the deployment change. If accepting images from the wild, dedicated image processing is a Good Idea because there are

Solution will change as size and needs of the deployment change. If accepting images from the wild, dedicated image processing is a Good Idea because there are some images out there that to nasty things to any/all of the image manipulation libs available. For giving the image to the image processor, I kind of like just using NFS. Simple, works up to a pretty big load, and when it does you will have a better feel for your operational needs -- everying is different. In terms of libraries to use, I think ImageMagick (via C!) and JAI (Java) are probably the best available. There are more, and YMMV, but I'd start with one of them. In terms of designing the app, well, that depends on what exactly you need!