The position of the source device providing input through this port.
Mac Catalyst 13.0+
All ports contained in an AVCaptureInput object’s ports array have the same sourceDevicePosition value.
When working with a microphone input in an AVCaptureMultiCamSession, it’s possible to record multiple microphone directions simultaneously. For example, you can record audio from the front microphone input to pair with video from the front camera, and record audio from the back microphone input to pair with video from the back camera.