Since the first stages of its drawing board phase, FreeSWITCH has been designed to excel in mixing capabilities. Streams can be combined and massaged by the core in an hyper-efficient way.

The media processing engine in FreeSWITCH core is very flexible, and provides hooks so that core developers and contributors can add features without ever risking to compromise stability and efficiency of the system.

There are two obvious main areas of media processing: audio and video. Audio and video are treated in a complete different way because of their own completely different nature.