Open Source Voice, Video and Fax

This project is a community effort to develop and support the OPAL VoIP library. OPAL implements the commonly used protocols used to send voice, video and fax data over IP networks.

Originally part of the OpenH323 project, OpalVoip has grown to include SIP and IAX2. OPAL is released under the Mozilla Public License 1.0 Open Source license.

Opal runs on Linux, Windows, MacOSX, xBSD, Solaris, and Windows Mobile.

Opal is a full-featured library that supports a variety of protocols and multi-media fornats.

Features include:

* Low latency RTP stack designed specifically for real-time multimedia
* Full featured H.323, SIP and IAX2 protocol stacks
* Audio codecs including G.711, GSM06.10, Speex and iLBC.
* Video codecs including H.261 and H.263
* Run-time loadable codec interface for proprietary or codecs such as G.729, H.263, H.264 and MPEG4
* Completely Open Source using the commercially friendly MPL 1.1 license

Through the use of a platform isolation library called PTLIB, Opal can run on tiny embedded systems or multi-processor servers.