An index is provided that holds information about each image content item in a collection of items, For each image content item, a first information item identifying the image content item and its location on a network, and at least one of (i) a second information item identifying a signature value of...http://www.google.co.uk/patents/US7945099?utm_source=gb-gplus-sharePatent US7945099 - System and method for use of images with recognition analysis
