extractors.frequency_estimator¶

Module: extractors.frequency_estimator¶

This program implements some of the frequency estimation functions from: https://gist.github.com/endolith/255291 and https://github.com/endolith/waveform-analyzer

Functions¶

mhealthx.extractors.frequency_estimator.freq_from_autocorr(signal, fs)¶

Estimate frequency using autocorrelation.

Pros: Best method for finding the true fundamental of any repeating wave, even with strong harmonics or completely missing fundamental

Cons: Not as accurate, doesn’t work for inharmonic things like musical instruments, this implementation has trouble with finding the true peak

From: https://gist.github.com/endolith/255291 and

https://github.com/endolith/waveform-analyzer

signal : list or array

time series data

fs : integer

sample rate

frequency : float

frequency (Hz)

mhealthx.extractors.frequency_estimator.freq_from_hps(signal, fs)¶

Estimate frequency using harmonic product spectrum.

Note: Low frequency noise piles up and overwhelms the desired peaks.

From: https://gist.github.com/endolith/255291 and

https://github.com/endolith/waveform-analyzer

signal : list or array

time series data

fs : integer

sample rate

frequency : float

frequency (Hz)