Yesterday Google added support for name tags to its Picasa Web Albums service. It relies heavily on face recognition software to make this task easy.

I'm no expert in this matter and I haven't been paying attention to the progress that has been made in this domain recently so I was surprised to see how good the face detection and recognition is.

(Warning: cheesy family pictures ahead!)

For example, when scanning my gallery Google correctly detects that all faces below belong to the same person (my oldest son Kiran):

You'll notice that the lightning in these pictures is very different (the darkest one is taken with a low resolution camera of a mobile phone), faces can be partially hidden and the presence of a baseball cap, a crown or even a red clown nose does not confuse the algorithm.

Of course not all faces were 100% correctly identified but overall the face recognition feature is really good and - as expected - the whole Ajax UI is easy to use and it feels very snappy. Impressive.