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<p class="MsoNormal">I am using the following simple pipeline to stream mulaw audio data to a port. My development machine is windows 7 and I’m using GStreamer 1.10.4 with your windows pre-built binaries.
<o:p></o:p></p>
<p class="MsoListParagraphCxSpFirst" style="margin-left:0in;mso-add-space:auto"><o:p> </o:p></p>
<p class="MsoListParagraphCxSpMiddle">gst-launch-1.0 -e --gst-debug=*:3 <o:p></o:p></p>
<p class="MsoListParagraphCxSpMiddle"><o:p> </o:p></p>
<p class="MsoListParagraphCxSpMiddle">filesrc location=C:/ test.wav ! <o:p></o:p></p>
<p class="MsoListParagraphCxSpMiddle"><o:p> </o:p></p>
<p class="MsoListParagraphCxSpMiddle">wavparse ! capsfilter caps="audio/x-mulaw,rate=8000,channels=1" !
<o:p></o:p></p>
<p class="MsoListParagraphCxSpMiddle"><o:p> </o:p></p>
<p class="MsoListParagraphCxSpMiddle">rtppcmupay max-ptime=20000000 ! <o:p></o:p></p>
<p class="MsoListParagraphCxSpMiddle"><o:p> </o:p></p>
<p class="MsoListParagraphCxSpMiddle">udpsink clients="192.168.1.103:6000" <o:p></o:p></p>
<p class="MsoListParagraphCxSpMiddle"><o:p> </o:p></p>
<p class="MsoListParagraphCxSpMiddle" style="margin-left:0in;mso-add-space:auto">
<o:p> </o:p></p>
<p class="MsoListParagraphCxSpMiddle" style="margin-left:0in;mso-add-space:auto">
The pipeline runs without errors. The problem is the receiving app [non-gstreamer] is expecting the rtp payload size to be fixed at 160 bytes of mulaw data. The above pipeline fails to do this. For a sample rate of 8000 Hz, 160 bytes of mulaw data corresponds
to 20 milliseconds of time. So I tried setting max-ptime as shown above but it doesn’t yield the desired result. I also tried playing with the mtu setting [for rtppcmupay] to no avail.
<o:p></o:p></p>
<p class="MsoListParagraphCxSpMiddle" style="margin-left:0in;mso-add-space:auto">
<o:p> </o:p></p>
<p class="MsoListParagraphCxSpLast" style="margin-left:0in;mso-add-space:auto">Is there any way to constrain the rtp payload size for rtppcmupay to a specific number of bytes?
<o:p></o:p></p>
<p class="MsoNormal">Thanks so much for your help, <o:p></o:p></p>
<p class="MsoNormal">Bill <o:p></o:p></p>
<p class="MsoNormal"> <o:p></o:p></p>
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