Instance Method

peakPowerForChannel:

Returns the peak power for a given channel, in decibels, for the sound being played.

Declaration

- (float)peakPowerForChannel:(NSUInteger)channelNumber;

Parameters

channelNumber

The audio channel whose peak power value you want to obtain. Channel numbers are zero-indexed. A monaural signal, or the left channel of a stereo signal, has channel number 0.

Return Value

A floating-point representation, in decibels, of a given audio channel’s current peak power. 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 player exceeds ±full scale, then the return value may exceed 0 (that is, it may enter the positive range).

Discussion

To obtain a current peak power value, you must call the updateMeters method before calling this method.

See Also

Using Audio Level Metering

meteringEnabled

A Boolean value that specifies the audio-level metering on/off state for the audio player.

- averagePowerForChannel:

Returns the average power for a given channel, in decibels, for the sound being played.

- updateMeters

Refreshes the average and peak power values for all channels of an audio player.

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