Documentation

Choose the path that matches what you want to do.

Use frei0r

Find installed plugins, use FFmpeg, and understand how applications expose effects.

Build and install

Download releases, use package managers, or build the collection with CMake.

Write a plugin

Implement the lifecycle, parameters and update function, then build and test it.

Understand the API

Learn the plugin types, color models and ABI before opening the complete generated reference.

Source of truth

• include/frei0r.h is the normative C API and specification.
• include/frei0r.hpp is the C++ convenience wrapper.
• src/filter/tutorial is the in-tree example.
• Generated API reference provides a browsable rendering.

Tutorials and demonstrations

Some linked videos show older software versions. They remain useful demonstrations, not current installation instructions.

Practical starting points

• Use frei0r with FFmpeg
• Develop a plugin from the in-tree tutorial
• Liquidsoap video documentation

From the project story

These links accompany frei0r: the free and open source video effect preservation project:

Resource	Kind	Context
Liquidsoap video documentation	Current documentation	Use with the article's Anonymizer example; the original 2.0.6 tutorial URL is no longer available
Liquidsoap - Anonymizer	Demonstration	A video anonymizer built with Liquidsoap and frei0r
Liquidsoap video / OSC integration	Demonstration	Programmable video controlled over OSC
Kdenlive 0.9.6 + Frei0r 14 Plugins	Historical tutorial	An older Kdenlive interface showing a range of effects
frei0r demo	Demonstration	A short tour of visual effects
The Art of the Algorithms	Historical context	Documentary on the demoscene culture behind many visual techniques

Videos are linked rather than embedded so visiting this site does not automatically contact YouTube.

For questions about adapting old examples to current software, join the frei0r discussion.