I was just having a nap and then that crazy idea came into my head. Here it is.
We have 2 different photos with face in each. How can we detect if there is the same person on that two photos?
Is it possible to do that? If yes, can I do it with Java or PHP? What the way to do it? Any ideas? Maybe each face has a "algorithm" or something which could help us?
Thank you very much.
It's not an trivial solution (and cannot be covered in an SO answer); you can start by reading papers on facial recognition. If this is something you really want to do, be prepared to read a lot of background information first before you actually start writing code. This subject matter is the basis for a lot of people's doctoral and masters theses. In this case, language is not as important as the algorithm. Also be prepared for lots of math. At the very least, you'll learn something cool. :)
The language doesn't really matter as long as it has the tools to do number crunching on the image data. Facial recognition is too big of topic for a forum post like this. I would just google "facial recognition algorithms".
I was freelancing a very similar task. Its not fun. almost impossible to build face recognition - face detection is easy, recognition is the tough part... the algorithm is generally a guarded secret as I've seen.
But I did find this: http://face.com/
Face recognition API. Feed it data, it feeds you names and details you've previously fed it. You have the ability to check to see if a face exists.
If you make a lot of requests or start working at an enterprise level - they charge.
I agree with the others that this is not trivial.