The LTP stack only mandates use of free software in its entire stack including the codecs.
- The LTP stack (source)
The LTP stack is a common source code that has been tested to work on Linux, Mac OSX, Windows (98 onwards), Windows Mobile (Pocket PC 2003 onwards) and Symbian (8.0 onwards) - LTP-Carbon 1.00.1b
LTP-Carbon 1.00.1 beta is out. Download and try it. Full conferencing, Push-to-Talk, Instant messaging and Presence on command line. - Speex for Windows Mobile (binary)
This is the binary build of Speex 1.1.12. It will work on Smartphone 2002, Pocket Pc 2003, Windows Mobile 5.0. - GSM 6.10 (source)
These are source files that have worked on all platforms including Mac OS X, Linux, Windows Desktop, Windows CE. Just add them to your build. - Asterisk LTP channel
The Asterisk LTP channel opens up LTP network to interconnects with all other protocols and provides a robust plaform for services.