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<p class="MsoNormal">Hello,<o:p></o:p></p>
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<p class="MsoNormal">I’ve been using Opus on an STM32 M4 platform for speech coding in mono mode. I thought I’d try stereo for grins to see if I can handle the CPU load, and I’m getting a return code of -1 from opus_decode_float (using CBR and 40ms frames).<o:p></o:p></p>
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<p class="MsoNormal">I decided to try the opusenc and opusdec tools to just see how the command line apps would behave. I am getting decoded audio, but I am losing the stereo separation. My test file has speech obtained with a Tascam Recorder, and I spoke
directly into each mic individually. I can clearly hear the stereo separation in the recorded audio. I do not hear any stereo separation once I encode from wav and decode back to wav. My encoding command line is “opusenc --hard-cbr --bitrate 16.000 --complexity
10 --framesize 20 stereo_voice.wav temp.opus”. My decoding script is: “opusdec --force-wav temp.opus decode.wav”. Opusenc reports that my encoded file is 2 channels (coupled) and opusdec reports that my file is 2 channels. Can someone tell me how to retain
my stereo separation? If I can’t get stereo separation from the codec, there’s no point in me investigating the error return in my ARM application.<o:p></o:p></p>
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<p class="MsoNormal">Kevin<o:p></o:p></p>
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