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What does “linear predictive encoding from xeroc park” mean ? Does it mean voice encoder ?

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Hi I found one of the RTP packet has this text "linear predictive encoding from xeroc park". I am trying to find which encoder might have been used during this communication. Can you please suggest me if it refers to the encoder and if there is any decoder to decode it . Any suggestion appreciated.

asked 11 May '15, 00:36

Shas's gravatar image

Shas
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One Answer:

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To quote RFC 1890, "RTP Profile for Audio and Video Conferences with Minimal Control":

4.4.9 LPC

LPC designates an experimental linear predictive encoding contributed
by Ron Frederick, Xerox PARC, which is based on an implementation
written by Ron Zuckerman, Motorola, posted to the Usenet group
comp.dsp on June 26, 1992.

and

LPC


An implementation is available at


        ftp://parcftp.xerox.com/pub/net-research/lpc.tar.Z</code></pre><p>although that FTP server doesn't seem to be working.</p></div><div class="answer-controls post-controls"></div><div class="post-update-info-container"><div class="post-update-info post-update-info-user"><p>answered <strong>11 May '15, 02:08</strong></p><img src="https://secure.gravatar.com/avatar/f93de7000747ab5efb5acd3034b2ebd7?s=32&amp;d=identicon&amp;r=g" class="gravatar" width="32" height="32" alt="Guy%20Harris&#39;s gravatar image" /><p><span>Guy Harris ♦♦</span><br />



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accept rate: 19%

@Guy Harris, Thanks. This session was captured during voip communication by a reputed app. I am surprised, some apps still using it. Isnt it too old to use ?

(11 May ‘15, 02:24) Shas