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How can I extract CQT from audio with sampling rate 8000 Hz (librosa)

I wrote following codes. 

sound_clip, s = librosa.load(fn, sr=8000)
cqtpec = librosa.cqt(y=sound_clip, sr=s)

But there was an error. 

librosa.util.exceptions.ParameterError: Filter pass-band lies beyond Nyquist

I wanna extract CQT feature from audio with sampling rate 8000 Hz.

HS Cho
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1 Answers1

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Use a lower n_bins or a lower fmin. With the default fmin of 32.7Hz (musical C1), n_bins = 84, and bins_per_octave = 12, the highest bin falls 7 octaves higher, at 4186Hz (C8), but with a sampling rate of 8000Hz you can only deal with frequencies up to 4000Hz, so if you keep fmin the same, n_bins needs to be no more than 83.

hobbs
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