This is a wrapper around Erik de Castro Lopo's libsamplerate (aka Secret Rabbit Code) for high-quality sample rate conversion.

It implements all three APIs available in libsamplerate:

• Simple API: for resampling a large chunk of data with a single library call
• Full API: for obtaining the resampled signal from successive chunks of data
• Callback API: like Full API, but input samples are provided by a callback function

Library calls to libsamplerate are performed using CFFI.

$ pip install samplerate

Binaries of libsamplerate for macOS and Windows (32 and 64 bit) are included and used if not present on the system. On Linux systems, you should also install libsamplerate0 (Debian derivatives), libsamplerate (Arch), or similar.

import numpy as np
import samplerate

# Synthesize data
fs = 1000.
t = np.arange(fs * 2) / fs
input_data = np.sin(2 * np.pi * 5 * t)

# Simple API
ratio = 1.5
converter = 'sinc_best'  # or 'sinc_fastest', ...
output_data_simple = samplerate.resample(input_data, ratio, converter)

# Full API
resampler = samplerate.Resampler(converter, channels=1)
output_data_full = resampler.process(input_data, ratio, end_of_input=True)

# The result is the same for both APIs.
assert np.allclose(output_data_simple, output_data_full)

# See `samplerate.CallbackResampler` for the Callback API, or
# `examples/play_modulation.py` for an example.

See samplerate.resample, samplerate.Resampler, and samplerate.CallbackResampler in the API documentation for details.

• scikits.samplerate implements only the Simple API and uses Cython for extern calls. The resample function of scikits.samplerate and this package share the same function signature for compatiblity.
• resampy: sample rate conversion in Python + Cython.

This project is licensed under the MIT license.

As of version 0.1.9, libsamplerate is licensed under the 2-clause BSD license.