Speex DSP Extension

SpeexDSP is a patent-free, Open Source/Free Software DSP library that is derived from the Speex library. You can find more information at https://www.speex.org.

The SpeexDSP Extension provides the following audio nodes for a Switchboard SDK audio graph:

Node	Description
EchoCancellerNode	Removes acoustic echo from microphone signal.
PreprocessorNode	Applies automatic gain control (AGC) and noise suppression on the voice signal.