Cortexica is an image recognition service. Some of their products include WineFindr, which allows users to compare prices of wine based on images and a video recognition application that allows users to take screengrabs of video.
The Cortexica REST API allows developers to access the functionality and content of Cortexica. Some example API methods include uploading images, matching images, and retrieving image information. Public documentation is not available; developers must register for access.