How to measure noise or sound and displays in dB(A) in iphone?

iphone objective-c audio meter
Mitul Nakum picture Mitul Nakum · May 31, 2011 · Viewed 8.3k times · Source

I want to measure sound in dB(A) in iPhone.

How can I do it?

Is there any example or tutorial?

Answer

tuoxie007 picture tuoxie007 · May 14, 2013

If you use AVAudioPlayer, you can use this method

AVAudioPlayer *avPlayer = ...
[avPlayer play...];
[avPlayer averagePowerForChannel:0];
[avPlayer averagePowerForChannel:1];

From Apple's doc

- (float)averagePowerForChannel:(NSUInteger)channelNumber

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

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