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<div>Hello, </div>
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<div>I am testing OPUS via the opus-tools package opus-tools-0.1.5-win32 (command line tool).</div>
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<div>I have a question regarding hybrid mode: </div>
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<li>I am using as input a 48 KHz sampling rate speech file, thus full band speech. I have tested several bitrates and frame sizes. According to the documentation, OPUS codec will work in hybrid mode when frame sizes of 10 or 20 ms are used, and bitrates from
40Kbps and above. However, the configuration info generated by the tool says that packets are coded either in LP mode (SILK) or MDCT mode (CELT), and I cannot see any reference to hybrid mode. Further reading the documentation, it says that the codec mode depends
on, among others, the type of signal (speech vs. music) and that currently this parameter needs to be provided to the application (no automatic detection). I understand from this that by default, OPUS works in music mode. But there is no means to set the parameter
to speech at least via a command line flag. How can OPUS be configured to work in speech mode for full band audio?</li></ul>
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<div>I also have a question regarding Packet Loss Concealment in hybrid mode:</div>
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<li>the documentation describes (section 4.4) a PLC method for CELT mode and one for SILK mode. What is the PLC algorithm when OPUS works in hybrid mode?</li></ul>
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<div>Thanks in advance.</div>
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<div style="margin-top: 5pt; margin-bottom: 5pt; ">Met vriendelijke groeten | Best Regards,<font face="Times New Roman, serif" size="3">
<br>
</font><b>Christian van Bijleveld<br>
<br>
</b>Bosch Security Systems BV<font face="Times New Roman, serif" size="3"> <br>
</font>Bosch Communications Systems, BL Public Address and Conference Systems (ST-CO/ENG1.3)<font face="Times New Roman, serif" size="3">
<br>
</font>P.O. Box 80 002<br>
5600 JB Eindhoven<font face="Times New Roman, serif" size="3"> <br>
</font>The Netherlands<font face="Times New Roman, serif" size="3"> <br>
</font><a href="http://www.boschsecurity.com"><font color="#0000FF"><u>www.bosch</u></font><font color="#0000FF"><u>security.com</u></font></a><font face="Times New Roman, serif" size="3"> </font></div>
<div style="margin-top: 5pt; margin-bottom: 5pt; ">T. +31 (0)40 257 7076<br>
F. +31 (0)40 257 7091<br>
<a href="mailto:christian.vanbijleveld@nl.bosch.com"><font color="#0000FF"><u>christian.vanbijleveld@nl.bosch.com</u></font></a></div>
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