<a href="http://www.voip-info.org/wiki/view/Codec+Patents">http://www.voip-info.org/wiki/view/Codec+Patents</a><br><br><div><span class="gmail_quote">On 6/17/07, <b class="gmail_sendername">Steve Underwood</b> <<a href="mailto:steveu@coppice.org">
steveu@coppice.org</a>> wrote:</span><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">Hi all,<br><br>There is an issue which is common ground for most free telephony
<br>projects - codec patents. In the near term we need to live within the<br>constraints of these patents, but they won't last forever (well, not as<br>long as Disney isn't a big patent holder). The snag is working out when
<br>they will be free. There are several relevant encumbered speech codecs,<br>potentially useful for what we do. The obvious ones are AMR-NB, AMR-WB,<br>G.722.1, G.722.2 (which is basically AMR-WB by another name), G.723.1
,<br>G.728, G.729, G.729.1. If you look through the ETSI and ITU web sites<br>you can find some material about who claims patents related to these<br>codecs. However, the information is far from complete. In most cases the
<br>actual patent numbers claimed to be relevant are not listed. The dates<br>of filing, granting and expiration are not generally listed, though if<br>the patent numbers are available the dates are easy to find.<br><br>I think it would be valuable to start a web page where all this
<br>information is gathered. We might then get a real picture of when a<br>codec will become unencumbered.<br><br>Clearly, video and even image, codecs are also of relevance to us.<br>However, I think the speech codecs would be a good starting point.
<br><br>Steve<br><br>_______________________________________________<br>Callweaver-users mailing list<br><a href="mailto:Callweaver-users@callweaver.org">Callweaver-users@callweaver.org</a><br><a href="http://lists.callweaver.org/mailman/listinfo/callweaver-users">
http://lists.callweaver.org/mailman/listinfo/callweaver-users</a><br></blockquote></div><br><br clear="all"><br>-- <br>wasim h. baig | principal consultant | convergence pk | +92 300 8508070