youtube filter

[meredith101]

how would that work? you submit a video, and they can tell if it's copyrighted material, by checking their database. How can they analyse a video like that, and so fast? Is it based on compression?

[pug100]

I belive they use digital watermarking, a kind of Digital Right Management
this has more info
http://en.wikipedia.org/wiki/Digital_rights_ma nagement