What is the format of the audio stream written to the ringbuf_i2s ?

[GrayEight]

Hello,

The audio Data-Stream from the phone is written to the RingBuffer ringbuf_i2s of type Byte buffer (defined in the bt_app_core.c file) by the write_ringbuf function, which is called in the bt_app_a2d_data_cb function.

But in which format is the data (used by the bt_app_a2d_data_cb function as a parameter) written to the RingBuffer ringbuf_i2s ? Is it still encoded as SBC-signal or decoded to what? just PCM?

I want to do a correlation with the streamed audio signal and a prestored signal.

Thx in advance,
Phil