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tlecomte / friture

Real-time audio visualizations (spectrum, spectrogram, etc.)
http://friture.org
GNU General Public License v3.0
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Overlap-add FFT filtering #3

Open tlecomte opened 13 years ago

tlecomte commented 13 years ago

Currently the octave spectrum uses IIR filters with decimation to go from one octave to the next. It would be smarter to use FIR instead of IIR filters, since they are more stable to numeric issues, and these FIR filters could be implemented with an overlap-add FFT algorithm for efficiency (keeping the decimation or not, depends on complexity - to be examined).

tlecomte commented 13 years ago

See http://projects.scipy.org/scipy/attachment/ticket/837/fftfilt.py for a (very basic) scipy implementation.