From what I remember from some student project many years ago, this technique is the basis for robust digital watermarking for any kind of signals, be it images or audio.
Of course the main application is to detect copyrighted material even after signals being heavily processed (e.g. ripped or cam’d movies, provided by JPEG-2000).
If anyone in the movie industry can provide some more technical details, I’m all ears!
I once tested a watermarking system (Digimarc?) and found that while it was robust against all sorts of noise and scaling, it failed with even a 1% rotation of the image. I wonder if it was a Fourier Transform based algorithm.
Of course the main application is to detect copyrighted material even after signals being heavily processed (e.g. ripped or cam’d movies, provided by JPEG-2000).
If anyone in the movie industry can provide some more technical details, I’m all ears!