"imgSeek
"imgSeek is a photo collection manager and viewer with
content-based search and many other features. The query is
expressed either as a rough sketch painted by the user or as
another image.
"Other key features:
"* Transform images or batches automatically: Place text captions,
change brightness, contrast, blur, etc. Apply lossless rotations
automatically if jpegtran is available.
* Supported file formats are jpg, gif, bmp, png, xbm, and pnm. If
you have ImageMagick installed, imgSeek will also support over 87
image formats."