Read an audio stream during (GSM) phone call

Is it possible to read an audio stream during (GSM) phone call? I would like to wr开发者_开发知识库ite an encoding application, and I do not want to go with SIP&VoIP. Thank you.

This will be phone and OS dependent and there are several apps that claim they record audio (Total Recall, Record my call on Android) but they generally seem to record via the microphone meaning the far end sound is poor.

I don't believe either the apple or android api's support access to the raw voice stream today.

Something to be aware of also is that it is not always legal to do this without informing the other party (i.e. the person on the other end of the call that you are planning to 'capture' the voice stream somehow) in many places - this may not be relevant for your particular plans but worth mentioning anyway.

If you have the option of doing the work in the network or on a PABX then you can create a basic (if not very efficient) solution by simply creating a three way (or conference) call.