It is a minimalistic plugin API for video sources and filters. The behaviour of the effects can be controlled from the host by simple parameters. The intent is to solve the recurring reimplementation or adaptation issue of standard effects.
It is not meant as a generic API for all kinds of video applications.
There is no support for the requirements of special application areas like non linear editors, hardware accelerated shader effects, and high precision video processing. These advanced issues are not even solved satisfactory for non cross application plugin apis and are still an evolving field.
The frei0r API is not meant to be a competing standard to more ambitious efforts.
There is a mailing list for frei0r issues.
The current api specification is located here.
The spec for the old 1.0 version is still available.
The following video applications support loading frei0r effects.
Drone is an open source software for digital and interactive arts. It allows design of realtime signal processing machines for video and audio through a generic data flow interface.
GePhex is an interactive effect system for video jockeys. The effects can be controlled with external devices like joysticks, web-cams, or midi-devices. New effects can be designed in a GUI by composing basic effects into more complex ones.
MøB is an environment for installations and realtime multimedia manipulation in GNU/Linux-based networks.
The frei0r api was designed by Georg Seidel, Phillip Promesberger and Martin Bayer at the Piksel meeting in Bergen. The design ideas were influenced by the experience with our own internal api and the cross application efforts like livido and freeframe.
Carlo Prelz contributed many refinements during his implementation of the frei0r loader for the MøB Application.
Gisle Frøysland from BEK organised the Piksel meeting in Bergen and is now sponsoring the virtual home of the frei0r project.