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<p class="MsoNormal"><span style="font-size:11.0pt">OK, so I missed this part in gstaudiotestsrc.c ...<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> if (G_UNLIKELY ((src->wave == GST_AUDIO_TEST_SRC_WAVE_SILENCE)<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> || (src->volume == 0.0))) {<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> GST_BUFFER_FLAG_SET (buffer, GST_BUFFER_FLAG_GAP);<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> }<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">So that explains the GAP buffers.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">But I'm still confused why I encounter problems.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">I created a small test tone using audacity (DTMF 1, 48000Hz, 50milliseconds).<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">This pipeline works fine every time:<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">gst-launch-1.0 audiotestsrc do-timestamp=true is-live=true volume=0.01 freq=1000 ! audiomixer name=mix ! audioconvert ! audio/x-raw,channels=1,sample-rate=48000,format=S16LE ! queue ! alsasink filesrc location=/root/audacity_dtmf_1.wav
blocksize=960 do-timestamp=true ! rawaudioparse pcm-format=s16le sample-rate=48000 num-channels=1 ! mix.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">Start the above, and ctrl-c once you've heard the dtmf tone play. Repeat several times.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">This pipeline occassionally has audio glitches in the dtmf tone, or sometimes doesn't even play the dtmf tone:<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">gst-launch-1.0 audiotestsrc do-timestamp=true is-live=true volume=0 freq=1000 ! audiomixer name=mix ! audioconvert ! audio/x-raw,channels=1,sample-rate=48000,format=S16LE ! queue ! alsasink filesrc location=/root/audacity_dtmf_1.wav
blocksize=960 do-timestamp=true ! rawaudioparse pcm-format=s16le sample-rate=48000 num-channels=1 ! mix.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">I feel like I must be missing something, or I'm just misunderstanding some basic concept.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
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