swipe_slim

Description: libf0 SWIPE slim implementation
Contributors: Sebastian Rosenzweig, Simon Schwär, Meinard Müller
License: The MIT license, https://opensource.org/licenses/MIT
This file is part of libf0.
libf0.swipe_slim.swipe_slim(x, Fs=22050, H=256, F_min=55.0, F_max=1760.0, R=10, strength_threshold=0)[source]

Slim and didactical implementation of a sawtooth waveform inspired pitch estimator (SWIPE). This version uses a log-frequency spectrogram instead of ERB filters. Furthermore, it is implemented more efficiently. See swipe() for the original implementation.

Parameters:

  • x (ndarray) – Audio signal

  • Fs (int) – Sampling rate

  • H (int) – Hop size

  • F_min (float or int) – Minimal frequency

  • F_max (float or int) – Maximal frequency

  • R (float) – resolution of the pitch candidate bins in cents (default = 10)

  • strength_threshold (float) – confidence threshold [0, 1] for the pitch detection (default value = 0)

Returns:

  • f0 (ndarray) – Estimated F0-trajectory

  • t (ndarray) – Time axis

  • conf (ndarray) – Confidence / Pitch Strength

libf0.swipe_slim.compute_kernel(f, F_coef_log_hz)[source]

Compute a SWIPE’ kernel.

Parameters:

  • f (float) – Frequency in Hz

  • F_coef_log_hz – Logarithmic frequency axis in Hz

Returns:

k – Kernel

Return type:

ndarray

libf0.swipe_slim.prime_and_one(upto=1000000)[source]

Returns a set of prime numbers, adapted from http://rebrained.com/?p=458

Parameters:

upto (int) – Find prime numbers up to this number

Return type:

A set of prime numbers including 1 & 2