GAPK Integration » History » Version 3
fixeria, 07/16/2018 06:04 PM
1 | 1 | fixeria | h1. GAPK Integration |
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3 | [[GAPK:|GAPK (GSM Audio Pocket Knife)]] is a "FFmpeg":https://www.ffmpeg.org/ like project focused on GSM related codecs (HR/FR/EFR/AMR) and formats. Since the _libosmogapk_ was introduced, it becomes possible to link [[OsmocomBB:]] against it and use its API for audio processing, i.e. for both voice capture and playback. |
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4 | 3 | fixeria | |
5 | Some initial work around this was already done, and has been published in a separate branch ("fixeria/audio":https://git.osmocom.org/osmocom-bb/log/?h=fixeria/audio). |
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7 | h2. PHY support |
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9 | Both [[TRX_Interface#The-trxcon-application|trxcon]] and [[cellular-infrastructure:Virtual_Um|VIRT-PHY]] do forward TCH frames to the higher layers (e.g. [[mobile]]) by default, while [[HardwareCalypso|Calypso]]-based phones can handle them either within DSP (both regular phone's mic and speaker are involved), or also forward them via L1CTL. The forwarding behaviour can be enabled using _L1CTL_TCH_MODE_REQ_ message and its _AUDIO_TX_TRAFFIC_REQ_ | _AUDIO_RX_TRAFFIC_IND_ flags. |