Good info, Luc. I keep hitting patent pages while searching about this area, it’s a bit of a minefield. I don’t suppose making it a FOSS offering would change matters, hm?

I switched to fftw – it’s a tiny library compared with openframeworks, with super-fast execution, plus it handles n-dimensional transforms.

The idea of jumping up an abstraction level to the methods used in facial recognition – intriguing. I’ll hafta look into that.

“…the identifier for a time segment is the difference between the highest and lowest amplitude.”

Another interesting idea, I’ll add it to my test case list. First, I gotta get my code working under fftw.

Another cool thing about fftw, it does runtime precompilation of an analysis – the initial compilation takes hundreds of millis (depending on CPU), and then the actual FFT transforms on live samples take microseconds after that.

I’m gonna keep chipping away at this til I got some answers… just curious.