Via ReadWriteHack:

Hack of the Day: Face Detection with HTML5 & JavaScript.

It’s a pretty cool idea. Taking a quick look at the source code (particularly the ccv.js file), it seems like it’s using something along the lines of the Viola-Jones boosted cascade of simple features algorithm. I’m guessing the actual cascade values (found in the face.js file) were trained in a non-javascript program.

It’s really too bad that no browsers support the HTML5 <device> tag yet, as it isn’t yet finalized. I’ve seen Flash apps which do some processing on camera input in the past, but having computer vision algorithms written in Java/Javascript/HTML5, running on the browser and integrated in web applications could be quite powerful. There’s of course all manner of games and toys one could come up with, but there’s also possibilities for things like authentication, changing the view when a face is no longer detected nearby, etc.