Question

此tutorial代码适用于我。我把它设置为吐出lowPAssResult的值。确实如此，在手机上运行它......

2011-07-04 14：28：08.672 MicBlow [280：707]检测到麦克风：0.036449 ......等等，如果我吹进它，价值就会上升。一切都好。

但是当我把它放在我自己的项目框架中时，它不起作用。我把这段代码放在我的init函数中......

//Set up the mic stuff
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 record];
    recorder.meteringEnabled = YES;        
    levelTimer = [NSTimer scheduledTimerWithTimeInterval: 0.03 target: self selector: @selector(levelTimerCallback:) userInfo: nil repeats: YES];
}

并添加了此回调

- (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;  

    NSLog(@"Mic blow detected -  peakPowerForChannel : %f, lowPassResults: %f",peakPowerForChannel,lowPassResults);
}

输出看起来像这样;

2011-07-04 14：30：32.974 MinuteGames [290：707]检测到麦克风：0.000001 反复。每一帧

无论我吹多少。请帮忙，我相信这一定很简单！

iPhone Mic Level：代码在一个项目中工作，而不是在另一个项目中

0 个答案: