A small package with stateful audio limiter implementation in Cython. Since the limiter is stateful it is suitable for streaming audio processing.
We're slowly growing into other effects beyond limiter, starting with streaming reverb in v0.4.
from cylimiter import ReverbRIR reverb = ReverbRIR() # default RIR # or user-provided RIR: # reverb = ReverbRIR([0.001, 0.021, 0.007, ...]) reverb.apply(audio) # makes a copy reverb.apply_inplace(audio) # no copies with np.array input # preserves context between calls for streaming applications for chunk in audio_source: reverb.apply_inplace(chunk)import numpy as np from cylimiter import Limiter limiter = Limiter(attack=0.5, release=0.9, delay=100, threshold=0.9) chunk_size = 1200 # for streaming processing # Example of applying limiter in-place (more efficient) audio = np.random.randn(44100) * 10 for i in range(0, 44100, chunk_size): chunk = audio[i : i + chunk_size] limiter.limit_inplace(chunk) # ... do sth with chunk # Example of applying limiter that copies the signal audio = np.random.randn(1, 44100) * 10 audio_lim = limiter.limit(audio) # Reset the limiter to re-use it on other signals limiter.reset()From PyPI via pip:
pip install cylimiterFrom source:
git clone https://github.com/pzelasko/cylimiter cd cylimiter pip install .Re-generate C++ sources from Cython:
cd extensions cython -3 --cplus *.pyxI couldn't easily find a package that implements audio limiter in Python in a suitable way for streaming audio. The closest (and the main inspiration) is this gist by @bastibe. Since the algorithm is auto-regressive, I figured C++ will be much more efficient than Python.