Code and theory of a look-ahead compressor/limiter.
The purpose of this project to demonstrate and describe, how a look-ahead limiter works and how to implement it. About 95%1 of all the sources (books, internet articles and forum threads) recommend a very easy way to implement the look-ahead feature, but unfortunately, 100%2 of those applications will lose their ability to limit the signal's level.
With this, I want to shed a little light on the mystery of look-ahead limiters 😉
Clicking the following links brings you directly to the docs.
This repository includes:
- C++ classes
- computation of the gain reduction from a given side-chain signal
- look-ahead processing of the gain reduction samples
- JUCE class: a compressor class which wraps the gain reduction class into a JUCE audio processor
- JUCE example projects
- SimpleCompressor: making use of the wrapper, implementing a compressor without look-ahead
- LookAheadCompressor: compressor / limiter with look-ahead feature
- thirdpary classes for multi-channel samples-delays and visualization of the compressor characteristic
- a tutorial: How to implement look-ahead limiters
The compressor class is mainly based on this presentation:
The sample delay class and visualization class is taken from the IEM Plug-in Suite
- website: https://plugins.iem.at
- source-code: https://git.iem.at/audioplugins/IEMPluginSuite
