I am trying to run the following code on my device with no success. Although the code works perfectly on Simulator. I have been following this tutorial. It simply crash on device.
http://mobileorchard.com/tutorial-detecting-when-a-user-blows-into-the-mic/
Code is:
http://mobileorchard.com/tutorial-detecting-when-a-user-blows-into-the-mic/
Code is:
Code:
@interface MicBlowViewController : UIViewController
{
AVAudioRecorder *recorder;
NSTimer *levelTimer;
double lowPassResults;
}
- (void)levelTimerCallback:(NSTimer *)timer;
@end
- (void)viewDidLoad
{
[super viewDidLoad];
NSURL *url = [NSURL fileURLWithPath:@"/dev/null"];
NSDictionary *settings = [NSDictionary dictionaryWithObjectsAndKeys:
[NSNumber numberWithFloat: 44100.0], AVSampleRateKey,
[NSNumber numberWithInt: kAudioFormatAppleLossless], AVFormatIDKey,
[NSNumber numberWithInt: 1], AVNumberOfChannelsKey,
[NSNumber numberWithInt: AVAudioQualityMax], AVEncoderAudioQualityKey,
nil];
NSError *error;
recorder = [[AVAudioRecorder alloc] initWithURL:url settings:settings error:&error];
if (recorder)
{
[recorder prepareToRecord];
recorder.meteringEnabled = YES;
[recorder record];
levelTimer = [NSTimer scheduledTimerWithTimeInterval: 3
target: self
selector: @selector(levelTimerCallback:)
userInfo: nil
repeats: YES];
}
else
NSLog(@"%@", [error description]);
}
- (void)levelTimerCallback:(NSTimer *)timer
{
[recorder updateMeters];
const double ALPHA = 0.05;
double peakPowerForChannel = pow(10, (0.05 * [recorder peakPowerForChannel:0]));
lowPassResults = ALPHA * peakPowerForChannel + (1.0 - ALPHA) * lowPassResults;
if (lowPassResults < 0.95)
NSLog(@"Mic blow detected");
}
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