The GSM Audio Picket Knife is a tool that can help you to convert codec frames of all codecs in GSM networks between a variety of different formats / representations.
It is part of the Osmocom Open Source Mobile Communications project.
You can clone from the official gapk.git repository using
git clone https://gitea.osmocom.org/osmocom/gapk.git
There is a web interface at https://gitea.osmocom.org/osmocom/gapk.
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