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Re: [whatwg] <device> element, streams and peer-to-peer connections

From: James Salsman <jsalsman@gmail.com>
Date: Mon, 31 May 2010 09:29:55 -0700
Message-ID: <AANLkTim_U-uvOhg4xs1xSqwig5pIiYy9CJmQ_4_Lfl1H@mail.gmail.com>
To: Mark Frohnmayer <mark.frohnmayer@gmail.com>
Cc: whatwg@lists.whatwg.org, public-device-apis@w3.org
On Mon, May 31, 2010 at 7:07 AM, Mark Frohnmayer
<mark.frohnmayer@gmail.com> wrote:
> On Sun, May 30, 2010 at 6:01 PM, James Salsman <jsalsman@gmail.com> wrote:
>>... With phase vocoder time shifting,
>> UDP delivery as per http://dev.w3.org/html5/html-device/#stream-api
>> would be far superior in quality and intelligibility under packet loss
>> or delay, assuming they went with an open audio codec (or, even
>> better, allowed a choice of speex or ogg vorbis.)
>...
> Where is the discussion regarding phase vocoder time shifting and UDP
> delivery?  I didn't see it in the stream-api section.

Some vendors such as Vivox use phase vocoder time shifting to shorten
audio segments to catch delayed streams back up to the wall clock.  It
works even better with TCP or RTP --
http://www.ietf.org/rfc/rfc3550.txt -- as with UDP, because the
application layer programmer just has to re-invent the transmission
control wheel with UDP anyway.
Received on Monday, 31 May 2010 16:30:28 UTC

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