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<p class="MsoNormal">Hello,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I have two Gstreamer applications communicating via WebRTC where one application sends audio and video to the other. Audio is currently encoded using OPUS, but I would like to change it to FLAC. The only info I have been able to find about
using FLAC and WebRTC is this old thread: <a href="http://gstreamer-devel.966125.n4.nabble.com/RTP-payload-for-FLAC-audio-format-td4665972.html">
http://gstreamer-devel.966125.n4.nabble.com/RTP-payload-for-FLAC-audio-format-td4665972.html</a>, which suggests using rtpgstpay, but I am not sure how to get this to work.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">My current sender audio pipeline (later connected to webrtcbin) is:<o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:Consolas;color:#2A00FF;background:#E8F2FE">appsrc ! audio/x-raw, channels=1, rate=16000, format=S16LE, layout=interleaved ! audioconvert ! audioresample ! queue !
</span><b><span style="font-size:10.0pt;font-family:Consolas;color:#2A00FF;background:#CCCCCC">opusenc</span></b><b><span style="font-size:10.0pt;font-family:Consolas;color:#2A00FF;background:#E8F2FE"> !
</span></b><b><span style="font-size:10.0pt;font-family:Consolas;color:#2A00FF;background:#CCCCCC">rtpopuspay</span></b><b><span style="font-size:10.0pt;font-family:Consolas;color:#2A00FF;background:#E8F2FE"> ! queue ! capsfilter caps=application/x-rtp,media=audio,encoding-name=</span></b><b><span style="font-size:10.0pt;font-family:Consolas;color:#2A00FF;background:#CCCCCC">OPUS</span></b><b><span style="font-size:10.0pt;font-family:Consolas;color:#2A00FF;background:#E8F2FE">,payload=96</span></b><o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I have tried changing it to:<o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:Consolas;color:#2A00FF;background:#E8F2FE">appsrc ! audio/x-raw, channels=1, rate=16000, format=S16LE, layout=interleaved ! audioconvert ! audioresample ! queue !
</span><b><span style="font-size:10.0pt;font-family:Consolas;color:#2A00FF;background:#CCCCCC">flacenc</span></b><b><span style="font-size:10.0pt;font-family:Consolas;color:#2A00FF;background:#E8F2FE"> !
</span></b><b><span style="font-size:10.0pt;font-family:Consolas;color:#2A00FF;background:#CCCCCC">rtpgstpay</span></b><b><span style="font-size:10.0pt;font-family:Consolas;color:#2A00FF;background:#E8F2FE"> ! queue ! capsfilter caps=application/x-rtp,media=audio,encoding-name=</span></b><b><span style="font-size:10.0pt;font-family:Consolas;color:#2A00FF;background:#CCCCCC">FLAC</span></b><b><span style="font-size:10.0pt;font-family:Consolas;color:#2A00FF;background:#E8F2FE">,payload=96</span></b><o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">But this fails with error message: <o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:Consolas;color:red">could not link queue7 to capsfilter6</span><o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Any idea what I need to do differently?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span style="font-size:9.0pt;font-family:"Verdana",sans-serif;color:#86807D;mso-fareast-language:EN-GB">Best regards,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:9.0pt;font-family:"Verdana",sans-serif;color:#86807D;mso-fareast-language:EN-GB">Thorsten</span><span style="font-size:12.0pt;mso-fareast-language:EN-GB"><o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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