Implement the beep-beep-sync method
There is currently an unknown delay between the audio signal (captured by the ADR host system's audio device) and the signals coming from the measurement hardware backend. A synchronization method could work as follows:
(0. The measurement hardware is outfitted with a buzzer that is loud enough so that it's beep is captured by the recording microphone.)
- Instead of having the hardware backend start measuring as soon as it is switched on with a hardware switch, the ADR sends a "start" signal to the hardware when recording shall begin.
- For the duration of the first measurement frame, the hardware buzzer beeps.
- When the recording is stopped in the ADR, the ADR sends a "stop" signal to the hardware and once again the hardware buzzer beeps for the duration of the final measurement frame.
- Since the beeps should be easily identifiable in the recorded audio signal, the sensor and audio data can now be aligned precisely.