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jitsi / libjitsi

Advanced Java media library for secure real-time audio/video communication.
Apache License 2.0
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AMR-WB: Enable VAD/DTX and use GSM compatible bitrate as default. #515

Closed traud closed 4 years ago

traud commented 4 years ago

AMR-WB is the bandwidth-efficient sibling of the HD audio codec G.722. Therefore, really leverage it features and enable voice-activation detection (VAD) so the RTP packets are transmitted discontinuously (DTX). Although this works with all versions of the encoder, at least version 0.1.5 of the OpenCORE-AMR decoder is recommended (comes in Debian 11 and Ubuntu 20.04 LTS), because previous versions had a bug in the Silence Descriptor (SID) decoding which resulted in white noise. Furthermore, to reduce the bandwidth even more, do not use the highest (AMR-WB Mode 8) but the GSM compatible bitrate as default (AMR-WB Mode 2). That still gives HD audio but works not only on UMTS (3G) but even on GSM links (2G).

traud commented 4 years ago

The next step would be making this default configurable from Jitsi Desktop → Menu → Options → Advanced → AMR.

jitsi-jenkins commented 4 years ago

Hi, thanks for your contribution! If you haven't already done so, could you please make sure you sign our CLA (https://jitsi.org/icla for individuals and https://jitsi.org/ccla for corporations)? We would unfortunately be unable to merge your patch unless we have that piece :(.