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yogen81

macrumors newbie
Original poster
Jun 26, 2009
3
0
Hi all,

We are creating an application which records the surrounding sound and take necessary action if the sound crosses specified Decibel.

In order to achieve the application objective we are using following method from AudioQueueObject.h

- (void) getAudioLevels: (Float32 *) levels peakLevels: (Float32 *) peakLevels {

UInt32 propertySize = audioFormat.mChannelsPerFrame * sizeof (AudioQueueLevelMeterState);
AudioQueueGetProperty(
self.queueObject,
(AudioQueuePropertyID)kAudioQueueProperty_CurrentLevelMeterDB,
self.audioLevels,
&propertySize);

levels[0] = self.audioLevels[0].mAveragePower;
peakLevels[0] = self.audioLevels[0].mPeakPower;
}

We have the following set of queries

1. The recorded sound shows the value in Decibel starting from -60. This value goes on increasing the moment sound gets louder. Maximum value recorded with this object is 0.0000. Please explain us how to interpret these values.
 
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