Ask HN: What face recognition framework should I use?

OpenCV is my favorite Computer Vision (CV) library. http://opencv.willowgarage.com/wiki/

Face detection is a special case of Haar-wavelets, which are essiantially recognitions that can be 'trained' by reinforcing with positive and negative images.

OpenCV comes with some really well pre-trained Haar-wavelets for recognizing faces. http://opencv.willowgarage.com/wiki/FaceDetection

Open CV is free and decent to start with. Lots of wrappers exist for it so you could pretty much use it with whatever environment you are using. If your idea is validated you could then look into some of the more expensive commercial libraries out there. They would give you more features flexibility scale and (maybe) better results.

http://face.com (if you can afford API calls)