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...
Hi developers, I like to update an existing iPhone application which is using AudioQueue for playing audio files. The levels (peakPowerForChannel, averagePowerForChannel) were linear form 0.0f to 1.0f. Now I like to use the simpler class AVAudioPlayer which works fine, the only issue is that the levels which are now in decibel, not li...
I am working on an Iphone app which records the sound pressure level in decibels on the headset speakers of a user. Can anyone guide me how to do this? I am not getting the exact functions to refer to so as to achieve this task. Thanks Ronny ...
The AVAudioRecorder in the iPhone SDK can be used to get the peak and average power for a channel, in decibels. The range is between 0db to 160db. What is the calculation used to convert this into a scale between 0 - 10 or something similar that can be used for an audio level meter? ...
Hello, I am trying to make a simple volume meter for the iPhone. I want the volume displayed in dB. When using this turorial, I am only getting measurements up to 78 dB. I've read that that is because the dBFS spectrum for 16 bit audio recordings is only 96 dB. I tried modifying this piece of code in the init funcyion: dataFormat.mSa...
The standard abbreviations for decibels is "dB" (note the case!) So, if I have a variable, holding (for instance) a maximum dB value, how best to name it? maxDbValue maxdBValue maxDecibelValue something else? Each has disdvantages - #1 swaps the case of the unit, #2 doesn't clearly split max from dB, and #3 is verbose... I think #...
Hello All, I am working with audio in the iPhone OS and am a bit confused. I am currently getting input from my audio buffer in the form of pcm values ranging from -32767 to 32768. I am hoping to perform a dbSPL conversion using the formula 20LOG10(p/pref). I am aware that pRef is .00002 pascals, and would like to convert the pcm va...
lowPassResults = ALPHA * peakPowerForChannel+ (1.0 - ALPHA)* lowPassResults; i m changing this value in decibel through this function. decibels = 10 * log10 (lowPassResults); then if lowPassResults value is .00001 then 50db and lowPassResults value is .0000001 then 70db But if it is detecting less noise then it is giving less val...
Now I m using the class AVAudioPlayer . But still i m not getting right value in decibel. there is any way to get the value in decibel range 0.0 to 120.0 (not in -0.0 to -120). if yes then plz tell me some body.... ...