- From: Janina Sajka <janina@rednote.net>
- Date: Tue, 14 Dec 2010 12:55:56 -0500
- To: Doug Schepers <schepers@w3.org>
- Cc: "Penkler, David" <dave.penkler@hp.com>, Noah Mendelsohn <nrm@arcanedomain.com>, Philippe Le Hegaret <plh@w3.org>, "public-xg-audio@w3.org" <public-xg-audio@w3.org>
Hello Doug and All: Doug Schepers writes: > Penkler, David wrote (on 12/14/10 10:36 AM): > >>From: Noah Mendelsohn > >>>noting that streaming is out of scope except for coordination > >>>with other groups > >> > >>Could you clarify what is meant by this? > > > >No it refers only to bidirectional real-time audio streams carried > >over RTP/UDP or such connecting two or more users between them or to > >a network interactive voice response unit such as voicemail system. > >This is basically the soft phone in a browser use case. One of the > >specific issues arising out of this use case is the need to > >synchronise the input and output streams in order to perform echo > >cancellation economically. The use cases for listening to a remote > >live performance over the internet with an audio enabled web browser > >or DAW's are not excluded. > I wonder if we would rather craft the charter more narrowly to exclude telephony and not exclude the use case of musicians performing together across the net? The latter use case is already well supported in the CELT codec from Xiph: http://www.celt-codec.org/ Quoting this page: "The CELT codec is a compression algorithm for audio. Like MP3, Vorbis, and AAC it is suitable for transmitting music with high quality. Unlike these formats CELT imposes very little delay on the signal, even less than is typical for speech centric formats like Speex, GSM, or G.729. "Using CELT application developers can build software that allows musicians to perform together across the Internet, or simply build great sounding telephony systems. Why shouldn't your telephone sound as good as your stereo?" I confess I have yet to use CELT to add my musical contribution to a performance, but I am well satisfied by the high quality of CELT and can testify to its low latency from having used it often in Vo/IP calls between Washington, DC and Melbourne, Australia. Yes, my experience is telephony, not musical performance--but the use case is real, imho, and should be supported. Do we expect realtime communications to support this use case? I don't know that I have a preference one WG over another--just that the use case get due consideration. Janina -- Janina Sajka, Phone: +1.443.300.2200 sip:janina@asterisk.rednote.net Chair, Open Accessibility janina@a11y.org Linux Foundation http://a11y.org Chair, Protocols & Formats Web Accessibility Initiative http://www.w3.org/wai/pf World Wide Web Consortium (W3C)
Received on Tuesday, 14 December 2010 17:56:35 UTC