Content Based Image Retrieval
Most Image search engines trie to find images based on the desciption (in the text) of the image (or meta-information in the image file itself), the tags that are applied to the image or the text surrounding the image on the webpage.
CBIR-search engines contains try to analyse the actual picture itself to find matches.It analyzes what the "input-image" looks like and tries to find similar images. Some can filter on color or shape, other require you to upload an image (p.e. from the web or your computer). Sep 12