Speex  1.2~beta4
Modules
Here is a list of all modules:
 Speex encoder and decoderThis is the Speex codec itself
 SpeexBits: Bit-stream manipulationsThis is the structure that holds the bit-stream when encoding or decoding with Speex. It allows some manipulations as well
 Various definitions for Speex callbacks supported by the decoder.
 SpeexEchoState: Acoustic echo cancellerThis is the acoustic echo canceller module
 SpeexHeader: Makes it easy to write/parse an Ogg/Speex headerThis is the Speex header for the Ogg encapsulation. You don't need that if you just use RTP
 JitterBuffer: Adaptive jitter bufferThis is the jitter buffer that reorders UDP/RTP packets and adjusts the buffer size to maintain good quality and low latency
 SpeexPreprocessState: The Speex preprocessorThis is the Speex preprocessor. The preprocess can do noise suppression, residual echo suppression (after using the echo canceller), automatic gain control (AGC) and voice activity detection (VAD)
 SpeexStereoState: Handling Speex stereo filesThis describes the Speex intensity stereo encoding/decoding