IETF 87 Berlin: WebRTC Opus Experiment

Next week the IETF will be holding a conference in Berlin. Part of that conference is a Technical Plenary Session about the Opus audio codec  scheduled for Monday, July 29th 5:40-7:40pm CET.

The IETF usually streams much of their conferences so people who are not free to travel may still participate. Quite often there’s an audio stream, sometimes there’s video and a web share of any slides. They usually stream from several of the meeting rooms, as multiple sessions are typical going on in parallel.

This coming Monday’s Technical Plenary is also going to be the basis of an experiment. The session is going to be streamed via WebRTC. That means that anyone with a WebRTC capable browser will be able to monitor the session. It further implies that the session on Opus will in fact be streamed using Opus…which seems only fitting.

The session will be recorded for those who cannot participate live. Since 5:40pm is Berlin is 10:40am in Houston I’m hopeful that I may be able to list in using Chrome.

Freeswitch En Route To Support For G.719 Codec

VVX_1500_D_Freeswitch.jpgThink back to the handful of new audio codecs that have been released over the past few years; CELT, SILK and Opus to name a few. Then there are the handful of proprietary codecs that have become available under more attractive licenses. Polycom’s Siren family come to mind on that front. In all of these cases I have observed that the Freeswitch development team are typically amongst the very first to implement any new codec.

In recent weeks they have added support for G.719, an ITU standard codec created by Polycom and Ericsson. With a  sample rate of 48 KHz, G.719 is a full-bandwidth codec, supporting a useful audio channel of 20 Hz- 20 KHz. It does so with end-to-end delay of only 40 ms and at bit rates from 32 kbps to 128 kbps. It also supports stereo audio.

Upon completion of the ITU standards process Polycom published a white paper on the codec; G.719: The First ITU-T Standard for Full-Band Audio (pdf).

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IEEE Spectrum Podcast With Dan Berninger of VCXC

IEEE-Spectrum-Podcast-in-thinkpad-x1-carbon Earlier this month Steven Cherry of the IEEE Spectrum podcast interviewed Daniel Berninger of The Voice Communications Exchange, aka VCXC, about the end of the PSTN. Dan certainly knows this space well. He covers a number of topics, including IP peering between carriers and potential new services, including HDVoice. It’s a good interview, well worth a listen.

However, like the CNet & Ooma interview from June 2012, the production of the interview is done completely ignoring the possibility of using HDVoice to craft the podcast itself.  I’m sure that this was a simple matter of choosing convenience over all else on the part of the IEEE staff.

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Polycom SoundPoint IP 550 / IP 650 Reviewed

Originally published at www.smallnetbuilder.com on August 13, 2008

When I was asked several months ago about reviewing a pair of new Polycom desk phones, I simply could not believe my good fortune. It was a little like being asked if I’d like to have a Tesla roadster for a few weeks. But of course my good man! Where do I sign?

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ZipDX: A Wideband Conference Service

A couple of weeks ago I penned a post about my search for a wideband capable soft phone. A short while later I was contacted by David Frankel of ZipDX. His company offers a standards compatible wideband conference service. It seems that he’s been down the path of wideband telephony a fair distance.

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Looking For A Wideband Capable Soft Phone

Over the coming weeks and months I hope to explore wideband voice in greater depth. My recent purchase of a couple of Polycom IP650s and the Siemens S685IP provide me with some hardware end-points. I may also buy a snom phone as well, with the optional Klarvoice handset.

However, some of what I wish to undertake would be well served by a soft phone. As yet I have been unable to find a software that supports the G.722 wideband codec.

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