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 you supply (or an image in your collection). The searching algorithm makes use of multiresolution wavelet decomposition of the query and database images.

imgSeek Features
You simply draw a rough sketch of what you want to find and imgSeek displays for you a thumbnail view of the best matches.
Query images similar to one in your collection by double-clicking on it's thumbnail.
Group your photos by similarity for easy browsing. You may also have them clustered automatically by color, date (group events automatically using an adaptive clustering algorithm for time differences), filename or image features.
Edit metadata (description, camera, lens, etc) for every image, and use them on the HTML albums generated or for searching photos. You can also use custom metadata fields.
EXIF and IPTC data found on JPEG/TIFF files are automatically imported. (Read-only support)
Advanced command-line utility to scan for new files, query for similar images and show image metadata. (You may use it on your cron system for example)
Transform images or batches automatically: Place text captions, change brightness, contrast, blur, etc. Apply lossless rotations automatically if jpegtran is available.
Generate HTML albums for the entire collection, a given directory or similarity group
And many more