Apple

How do I indicate recording level?

When you use an audio queue object (from Audio Queue Services, AudioToolbox/AudioQueue.h) for recording, you can query the audio queue object's kAudioQueueProperty_CurrentLevelMeterDB property to obtain the current recording level. The value of this property is an array of AudioQueueLevelMeterState structures, one per channel, as seen in Listing 1.

Listing 1: AudioQueueLevelMeterState structure

typedef struct AudioQueueLevelMeterState {

    Float32 mAveragePower;

    Float32 mPeakPower;

}; AudioQueueLevelMeterState;