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<p class="MsoNormal">I use the Opus multistream encoder for both mono and stereo encodings and after updating from 1.1.3 to 1.3 I noticed the size of the produced Opus files had doubled for 1-channel encodings whereas switching to the standand Opus encoder
gave me roughly the same sizes as before. In these tests, I’m encoding an 8kHz mono stream containing only speech with the following options set:<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">frame length = 20ms<o:p></o:p></p>
<p class="MsoNormal">application = voip<o:p></o:p></p>
<p class="MsoNormal">bandwidth = auto<o:p></o:p></p>
<p class="MsoNormal">max bandwidth = narrowband<o:p></o:p></p>
<p class="MsoNormal">bitrate = >unset<<o:p></o:p></p>
<p class="MsoNormal">force channels = auto<o:p></o:p></p>
<p class="MsoNormal">input precision = 14<o:p></o:p></p>
<p class="MsoNormal">vbr = true<o:p></o:p></p>
<p class="MsoNormal">fec = false<o:p></o:p></p>
<p class="MsoNormal">vad = false<o:p></o:p></p>
<p class="MsoNormal">complexity = 4<o:p></o:p></p>
<p class="MsoNormal">signal = auto<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Using the standard Opus encoder, I get a bit rate around 10kbps and using the Multistream encoder, I get a bit rate of around 20kbps.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I can explicitly set the bit rate back to 10kbps to get around this difference, but thought it was worth reporting in case this isn’t expected behavior.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Kevin O’Connor<o:p></o:p></p>
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