wishlist: allow 3rd party similarity measures

[drevicko]

When testing iskdaemon against other tools, the linux command line tool findimagedupes actually (and surprisingly) performed better. I'm looking at twitter images that have been cropped, resized, sometimes converted to black and white. Those that have been cropped significantly and some with significantly different sizes showed low similarity with iskdaemon (so low that I'd introduce many false positives if I allowed them) but were identified with findimagedupes. I'm not up with research in this area, but I'm sure new techniques will appear (probably already have), and that for specific tasks, different algorithms may perform better.

However, the web service interfaces of iskdaemon can be quite handy. It's the only tool I've found with that capability.

My suggestion is to setup a simple plugin api to allow other similarity measures to be added with relative ease. There are, of course, caveates:

• the 3rd party plugin would either have to maintain it's own db or provide compact signiture info for images. findimagedupes maintains a db of it's own.
• it would know nothing of images added before the plugin was added
• how to deal with image id's? I believe findimagedupes uses image paths. What to do with uploaded blobs?
• anything else??