Flickcurl is a library for implementing the Flickr API in C. This library supports the entire Flickr API, including functions for browsing, searching, and uploading photos and videos. It comes with a program called flickrdf that turns a photo's metadata, tags, machine tags, and places into RDF triples descriptions.
Recognize.im recently announced that its image recognition API service has publicly launched. Until now, the Recognize.im API remained accessible on an invite only basis. Recognize.im hopes to tap into the quickly growing image recognition market and target mobile shopping apps and advertising campaigns. The platform recognizes real-world objects and redirects customers to take action after the customer takes a photo of the object with a smartphone.