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<H1>Open source DSTAR voice - Codec2</H1>
<P><FONT face=Verdana>The DSTAR protocol is open and freely available, developed
by the Japanese Amateur Radio League (JARL). However, the AMBE voice encoding
scheme currently used by the DSTAR protocol is not open, rather it is patented
by DVSI, Inc. </FONT></P>
<P><FONT face=Verdana>Development on an open source, freely available
alternative to AMBE has been spearheaded by Australian amateur <STRONG>David
Rowe, VK5DGR</STRONG>. This <STRONG>open voice codec</STRONG> is called
<STRONG>Codec2</STRONG>, and is in a highly experimental stage at this current
point. It's advocates include Bruce Perens, K6BP, (</FONT><A
href="http://www.codec2.org/" target=_blank><FONT
face=Verdana>www.codec2.org</FONT></A><FONT face=Verdana>) who is well known in
open source software circles, and is a huge Free Software advocate. </FONT></P>
<P><FONT face=Verdana>What's the issue with AMBE? </FONT></P>
<P><FONT face=Verdana>Codec2 developer David Rowe, VK5DGR talks about this on
his blog: </FONT><A href="http://www.rowetel.com/blog/?p=128"
target=_blank><FONT
face=Verdana>http://www.rowetel.com/blog/?p=128</FONT></A></P>
<P><EM><FONT face=Verdana>"Due to patents and the amount of confidential
information surrounding these codecs (AMBE) I don’t think it is possible to make
an open codec compatible with these closed codecs. <STRONG>It is however
possible to develop a open source, free-as-in-speech codec with similar
performance at similar bit rates</STRONG>. [...] <STRONG>A free codec helps a
large amount of people and promotes development and innovation</STRONG>"
</FONT></EM></P>
<P><FONT face=Verdana> </FONT></P>
<P><FONT face=Verdana>David Rowe's development site is: </FONT><A
href="http://www.rowetel.com/ucasterisk/codec2.html" target=_blank><FONT
face=Verdana>www.rowetel.com/ucasterisk/codec2.html</FONT></A></P>
<P><FONT face=Verdana>He is currently looking for assistance, either financially
or with coding. Because of financial obligations, he's currently on hiatus from
development to pay bills with other work. Development milestones and source code
are available through his website. David can be contacted at his email: David
(at) rowetel.com </FONT></P>
<P><FONT face=Verdana>A <STRONG>DSTAR protocol implementing Codec2 Digital Voice
would significantly drop the entrance level and appeal to a much wider audience.
Once Codec2 is stable and competitive, it would offer a real, developed-by-a-ham
alternative to the patented AMBE voice encoder</STRONG>. </FONT></P>
<P><FONT face=Verdana>If you are able to help with development please contact
David Rowe!</FONT> <BR><BR></P></BODY></HTML>