Returns the average power for a given channel, in decibels, for the sound being recorded.
- iOS 3.0+
- macOS 10.7+
- watchOS 4.0+Beta
The number of the channel that you want the average power value for.
The current average power, in decibels, for the sound being recorded. A return value of 0 dB indicates full scale, or maximum power; a return value of -160 dB indicates minimum power (that is, near silence).
If the signal provided to the audio recorder exceeds ±full scale, then the return value may exceed 0 (that is, it may enter the positive range).
To obtain a current average power value, you must call the
update method before calling this method.