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<p class="MsoNormal">Thank you Kevin.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Any idea if Google developers may decide to reset the decoder, per Joshua’s experience?<o:p></o:p></p>
<p class="MsoNormal">Or perhaps asterisk developers would consider eventually add the rewrite support in asterisk?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Always fun dealing with newer technology as it goes through several revisions.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Have a great day!<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Dan<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><b>From:</b> asterisk-users <asterisk-users-bounces@lists.digium.com>
<b>On Behalf Of </b>Kevin Harwell<br>
<b>Sent:</b> Thursday, March 14, 2019 4:50 PM<br>
<b>To:</b> Asterisk Users Mailing List - Non-Commercial Discussion <asterisk-users@lists.digium.com><br>
<b>Subject:</b> Re: [asterisk-users] Does anyone know if there is a problem with the Chrome browser and asterisk cmp2k video<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">On Wed, Mar 13, 2019 at 10:15 AM Dan Cropp <<a href="mailto:dan@amtelco.com">dan@amtelco.com</a>> wrote:<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Using asterisk 16.1.1.<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">I’m setting up a test using the cmp2k (Cyber Mega Phone 2K Ultimate Dynamic Edition).<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">I have noticed Chrome 72 had some issues with video streams. I just upgraded to Chrome 73 and see they still have some issues. If I have 2 calls in a confbridge with video set
to none. I then set the video source to a Chrome browser and the Remote Video shown to both calls from Firefox and Chrome do not update. However, if I set the video source to the Firefox browser, my Remote Video is accurate in both Firefox and Chrome.<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">I confirmed that asterisk is indicating the video source changed by looking at the AMI BridgeVideoSourceUpdate event.<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">When I use the Firefox (65.0.2) browser I can set either call to be the video source and the Remote Video updates accordingly.<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Is this caused by Chrome’s video sent to asterisk being some format which asterisk can’t use in the confbridge?
<o:p></o:p></p>
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<p class="MsoNormal">The way I understand it is that video stream has changed, so the browser needs some way to know that. Otherwise the decoder thinks it's invalid data and drops it. In these cases either Asterisk needs to issue a renegotiation (currently
not supported), or the codec needs to contain video stream information in their payload. I spoke with Joshua Colp about this some as he's had some dealings with this and he had the following to say:<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">"Some codecs (such as VP8/V9) embed information about the video stream within their payload. Asterisk does not currently rewrite this information, so when a stream change occurs in Asterisk using the selective source functionality this
can cause the receiving side (the browser) to drop the payload as it sees it as not being part of the existing stream. Different browsers can behave differently, such as resetting the video decoder to<b><span style="color:#CC0000"> </span></b>handle the new
stream. Rewriting this information in the video payload is not currently supported."<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">So you are probably seeing it work or not in Chrome vs Firefox due to browser, and codec support of such occurrences.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"> .... <snip config> ....<o:p></o:p></p>
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<p class="MsoNormal">-- <o:p></o:p></p>
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<p class="MsoNormal">Kevin Harwell<o:p></o:p></p>
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<p class="MsoNormal">Digium - A Sangoma Company | Senior Software Developer<o:p></o:p></p>
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<p class="MsoNormal">445 Jan Davis Drive NW - Huntsville, AL 35806 - US<o:p></o:p></p>
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<p class="MsoNormal">Check us out at: <a href="https://digium.com" target="_blank">
https://digium.com</a> & <a href="https://asterisk.org" target="_blank">https://asterisk.org</a><o:p></o:p></p>
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