Short-Time Fourier Transform (STFT)

This module implements the Short-Time Fourier Transform (STFT) in Python using MLX.

It is designed to inherit from the nn.Module, which allows it to be used either as a standalone module or as part of a larger neural network architecture.

Installation

You can install mlx_stft directly from pypi:

pip install mlx_stft

Or you can install it directly from the source code:

git clone https://github.com/nuniz/mlx_stft.git
cd mlx_stft
python setup.py install

Usage

from mlx_stft import STFT

# Create an instance of the STFT module
stft = STFT(n_fft=1024, win_length=256, hop_length=128, return_db=True, onesided=True)

# Compute STFT of an audio signal
y = stft(x)

x: mx.array [batch, length]
y: mx.array [batch, n_fft // 2, size of fold] if one_sided else [batch, n_fft, size of fold]
where size of fold = 1 + length // hop_length

Arguments

n_fft: Number of Fourier transform points.
win_length: Length of the STFT window.
hop_length: Number of audio samples between adjacent STFT columns.
window: Type of window function to apply (default is "hann").
onesided: Whether to return only the non-redundant part of the spectrum (default is False).
return_db: Whether to return the result in decibels (default is False).

Example

The STFT is illustrated in the picture below using the NOIZEUS dataset's sp09.wav file.

One-Sided STFT

Dual-Sided STFT