Question

我知道有几个线程有相同的问题，但我无法使他们的解决方案工作。我最终创建了这个类：

MicroController.h

#import Foundation/Foundation.h>

#import <AVFoundation/AVFoundation.h>
#import <CoreAudio/CoreAudioTypes.h>

#import <UIKit/UIKit.h>

@interface MicroController : UIView < UITextFieldDelegate, UIImagePickerControllerDelegate, UINavigationControllerDelegate, AVAudioSessionDelegate > {
    AVAudioRecorder *recorder;
    NSTimer *levelTimer;
    double lowPassResults;
}

- (void)levelTimerCallback:(NSTimer *)timer;
@end

MicroController.mm

#import "MicroController.h"


@implementation MicroController

- (id)init
{
    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;

        if ([recorder prepareToRecord] == YES){
            [recorder record];
        }else {
            int errorCode = CFSwapInt32HostToBig ([error code]); 
            NSLog(@"Error: %@ [%4.4s])" , [error localizedDescription], (char*)&errorCode); 

        }

        levelTimer = [NSTimer scheduledTimerWithTimeInterval: 0.03 target: self selector: @selector(levelTimerCallback:) userInfo: nil repeats: YES];
    } else
        NSLog([error description]); 

    // input 'level' is in meter.mAveragePower

    return self;
}

- (void)levelTimerCallback:(NSTimer *)timer {
    [recorder updateMeters];

    const double ALPHA = 1.0; // 0.05f
    double peakPowerForChannel = pow(10, (0.05 * [recorder peakPowerForChannel:0]));
    lowPassResults = ALPHA * peakPowerForChannel + (1.0 - ALPHA) * lowPassResults;  

    if (lowPassResults > 0.55)
        NSLog(@"Mic blow detected");


    [recorder updateMeters];
    NSLog(@"Average input: %f Peak input: %f", [recorder averagePowerForChannel:0], [recorder peakPowerForChannel:0]);

}
    - (void)viewDidLoad {
        [super viewDidLoad];

        NSLog(@"initiated");

        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: 0.03 target: self selector: @selector(levelTimerCallback:) userInfo: nil repeats: YES];
        } else
            NSLog([error description]);

    }


    - (void)dealloc {
        [levelTimer release];
        [recorder release];
        [super dealloc];
    }
    @end

但我无法让麦克风工作。我只得到这个输出，麦克风永远不会响应：

平均输入：-120.000000峰值输入：-120.000000

有什么可能出错的想法吗？

感谢您的帮助！

Answer 1

嗯，我认为我正在与团结合作并不重要，这是罪魁祸首。

Unity修改了一些设置，因此在加载viewcontroller时执行此操作非常重要：

[[AVAudioSession sharedInstance]
 setCategory: AVAudioSessionCategoryPlayAndRecord
 error: &setCategoryError];
if (setCategoryError) {
    NSLog([setCategoryError description]);
}

否则完美编写的audiorecorder将无法正常工作。那就是问题解决了！

这个bug是一个可以检测的PAIN，我希望这条消息可以帮助其他人处于同样的困境。

Answer 2

好的，这是解决方法：文件“MicController.m”

#import "MicController.h"


static MicController *sharedListener = nil;


@implementation MicController


+ (MicController *)sharedListener {
    @synchronized(self) {
        if (sharedListener == nil)
            [[self alloc] init];
    }

    return sharedListener;
}

- (void)dealloc {
    //[sharedListener stop];
    //[levelTimer release];
    [recorder release];
    [super dealloc];
}

#pragma mark -
#pragma mark Listening

- (void)listen {

    [[AVAudioSession sharedInstance]
     setCategory: AVAudioSessionCategoryPlayAndRecord
     error: nil];




    NSURL *url = [NSURL fileURLWithPath:@"/dev/null"];

    //kAudioFormatAppleIMA4
    //kAudioFormatMPEG4AAC
    /*
    NSMutableDictionary *settings = [NSMutableDictionary dictionaryWithObjectsAndKeys:
                                     [NSNumber numberWithFloat: 44100.0],                 AVSampleRateKey,
                                     [NSNumber numberWithInt: kAudioFormatAppleLossless], AVFormatIDKey,
                                     [NSNumber numberWithInt: 1],                         AVNumberOfChannelsKey,
                                     [NSNumber numberWithInt: AVAudioQualityMax],         AVEncoderAudioQualityKey,
                                     nil];
    */

    NSDictionary *settings = [[NSDictionary alloc] initWithObjectsAndKeys:
                              [NSNumber numberWithFloat: 44100.0],                 AVSampleRateKey,
                              [NSNumber numberWithInt: kAudioFormatAppleLossless], AVFormatIDKey,
                              [NSNumber numberWithInt: 2],                         AVNumberOfChannelsKey,
                              [NSNumber numberWithInt: AVAudioQualityMax],         AVEncoderAudioQualityKey,
                              nil];
                              /*
                              [NSNumber numberWithFloat: 44100.0],                  AVSampleRateKey,
                              [NSNumber numberWithInt: kAudioFormatMPEG4AAC],      AVFormatIDKey,
                              [NSNumber numberWithInt: 2],                          AVNumberOfChannelsKey,
                              [NSNumber numberWithInt: AVAudioQualityMax],          AVEncoderAudioQualityKey,
                              [NSNumber numberWithInt:16],                          AVLinearPCMBitDepthKey,
                              [NSNumber numberWithBool:NO],                         AVLinearPCMIsBigEndianKey,
                              [NSNumber numberWithBool:NO],                         AVLinearPCMIsFloatKey,
                              nil];
                                */
    NSError *error;

    recorder = [[AVAudioRecorder alloc] initWithURL:url settings:settings error:&error];

    if (recorder) {
        [recorder prepareToRecord];
        recorder.meteringEnabled = YES;
        [recorder record];
        //levelTimer = [NSTimer scheduledTimerWithTimeInterval: 0.03 target: self selector: @selector(levelTimerCallback:) userInfo: nil repeats: YES];
    } else
        NSLog([error description]); 
}
- (void)stop {
    [recorder release];
}

/*
- (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");
    NSLog(@"Average input: %f Peak input: %f Low pass results: %f", [recorder averagePowerForChannel:0], [recorder peakPowerForChannel:0], lowPassResults);


}
 */

#pragma mark -
#pragma mark Levels getters

- (Float32)averagePower {
    [recorder updateMeters];

    const double ALPHA = 0.7;
    double peakPowerForChannel = pow(10, (0.05 * [recorder averagePowerForChannel:0]));
    lowPassResults = ALPHA * peakPowerForChannel + (1.0 - ALPHA) * lowPassResults;
    return [recorder averagePowerForChannel:0];
    //return lowPassResults;
    //NSLog(@"Average input: %f Peak input: %f Low pass results: %f", [recorder averagePowerForChannel:0], [recorder peakPowerForChannel:0], lowPassResults);

}
- (Float32)peakPower {
    [recorder updateMeters];

    const double ALPHA = 0.7;
    double peakPowerForChannel = pow(10, (0.05 * [recorder peakPowerForChannel:0]));
    lowPassResults = ALPHA * peakPowerForChannel + (1.0 - ALPHA) * lowPassResults;
    return [recorder peakPowerForChannel:0];
    //return lowPassResults;
    //NSLog(@"Average input: %f Peak input: %f Low pass results: %f", [recorder averagePowerForChannel:0], [recorder peakPowerForChannel:0], lowPassResults);

}

#pragma mark -
#pragma mark Singleton Pattern

+ (id)allocWithZone:(NSZone *)zone {
    @synchronized(self) {
        if (sharedListener == nil) {
            sharedListener = [super allocWithZone:zone];
            return sharedListener;
        }
    }

    return nil;
}

- (id)copyWithZone:(NSZone *)zone {
    return self;
}

- (id)init {
    if ([super init] == nil)
        return nil;

    return self;
}

- (id)retain {
    return self;
}

- (unsigned)retainCount {
    return UINT_MAX;
}

- (void)release {
    // Do nothing.
}

- (id)autorelease {
    return self;
}


@end

只需添加代码

即可

 [[AVAudioSession sharedInstance]
     setCategory: AVAudioSessionCategoryPlayAndRecord
     error: nil];

over de void“ - （void）listen {”

感谢。再见

Answer 3

我遇到同样的问题，在我使用Titanium appcelerator的情况下。在模拟器中，类正常工作，但在设备中没有，平均输入= -120 这是代码：

//
//  MicController.h
//  Mic
//
//  Created by DekWilde on 10/26/11.
//  Copyright 2011 DekWilde. All rights reserved.
//

#import <UIKit/UIKit.h>
#import <Foundation/Foundation.h>
#import <AVFoundation/AVFoundation.h>
#import <CoreAudio/CoreAudioTypes.h>

@interface MicController : NSObject {
    AVAudioRecorder *recorder;
    //NSTimer *levelTimer;
    double lowPassResults;  
}

+ (MicController *)sharedListener;
- (void)listen;
- (void)stop;
//- (void)levelTimerCallback:(NSTimer *)timer;
- (Float32)averagePower;
- (Float32)peakPower;
@end

和MicController.m

    #import "MicController.h"


    static MicController *sharedListener = nil;


    @implementation MicController


    + (MicController *)sharedListener {
        @synchronized(self) {
            if (sharedListener == nil)
                [[self alloc] init];
        }

        return sharedListener;
    }

    - (void)dealloc {
        //[sharedListener stop];
        //[levelTimer release];
        [recorder release];
        [super dealloc];
    }

    #pragma mark -
    #pragma mark Listening

    - (void)listen {

        NSURL *url = [NSURL fileURLWithPath:@"/dev/null"];

        //kAudioFormatAppleIMA4
        //kAudioFormatMPEG4AAC
        /*
        NSMutableDictionary *settings = [NSMutableDictionary dictionaryWithObjectsAndKeys:
                                         [NSNumber numberWithFloat: 44100.0],                 AVSampleRateKey,
                                         [NSNumber numberWithInt: kAudioFormatAppleLossless], AVFormatIDKey,
                                         [NSNumber numberWithInt: 1],                         AVNumberOfChannelsKey,
                                         [NSNumber numberWithInt: AVAudioQualityMax],         AVEncoderAudioQualityKey,
                                         nil];
        */

        NSDictionary *settings = [[NSDictionary alloc] initWithObjectsAndKeys:
                                  [NSNumber numberWithFloat: 44100.0],                 AVSampleRateKey,
                                  [NSNumber numberWithInt: kAudioFormatAppleLossless], AVFormatIDKey,
                                  [NSNumber numberWithInt: 2],                         AVNumberOfChannelsKey,
                                  [NSNumber numberWithInt: AVAudioQualityMax],         AVEncoderAudioQualityKey,
                                  nil];
                                  /*
                                  [NSNumber numberWithFloat: 44100.0],                  AVSampleRateKey,
                                  [NSNumber numberWithInt: kAudioFormatMPEG4AAC],      AVFormatIDKey,
                                  [NSNumber numberWithInt: 2],                          AVNumberOfChannelsKey,
                                  [NSNumber numberWithInt: AVAudioQualityMax],          AVEncoderAudioQualityKey,
                                  [NSNumber numberWithInt:16],                          AVLinearPCMBitDepthKey,
                                  [NSNumber numberWithBool:NO],                         AVLinearPCMIsBigEndianKey,
                                  [NSNumber numberWithBool:NO],                         AVLinearPCMIsFloatKey,
                                  nil];
                                    */
        NSError *error;

        recorder = [[AVAudioRecorder alloc] initWithURL:url settings:settings error:&error];

        if (recorder) {
            [recorder prepareToRecord];
            recorder.meteringEnabled = YES;
            [recorder record];
            //levelTimer = [NSTimer scheduledTimerWithTimeInterval: 0.03 target: self selector: @selector(levelTimerCallback:) userInfo: nil repeats: YES];
        } else
            NSLog([error description]); 
    }
    - (void)stop {
        [recorder release];
    }

    /*
    - (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");
        NSLog(@"Average input: %f Peak input: %f Low pass results: %f", [recorder averagePowerForChannel:0], [recorder peakPowerForChannel:0], lowPassResults);


    }
     */

    #pragma mark -
    #pragma mark Levels getters

    - (Float32)averagePower {
        [recorder updateMeters];

        const double ALPHA = 0.7;
        double peakPowerForChannel = pow(10, (0.05 * [recorder averagePowerForChannel:0]));
        lowPassResults = ALPHA * peakPowerForChannel + (1.0 - ALPHA) * lowPassResults;
        return [recorder averagePowerForChannel:0];
        //return lowPassResults;
        //NSLog(@"Average input: %f Peak input: %f Low pass results: %f", [recorder averagePowerForChannel:0], [recorder peakPowerForChannel:0], lowPassResults);

    }
    - (Float32)peakPower {
        [recorder updateMeters];

        const double ALPHA = 0.7;
        double peakPowerForChannel = pow(10, (0.05 * [recorder peakPowerForChannel:0]));
        lowPassResults = ALPHA * peakPowerForChannel + (1.0 - ALPHA) * lowPassResults;
        return [recorder peakPowerForChannel:0];
        //return lowPassResults;
        //NSLog(@"Average input: %f Peak input: %f Low pass results: %f", [recorder averagePowerForChannel:0], [recorder peakPowerForChannel:0], lowPassResults);

    }

    #pragma mark -
    #pragma mark Singleton Pattern

    + (id)allocWithZone:(NSZone *)zone {
        @synchronized(self) {
            if (sharedListener == nil) {
                sharedListener = [super allocWithZone:zone];
                return sharedListener;
            }
        }

        return nil;
    }

    - (id)copyWithZone:(NSZone *)zone {
        return self;
    }

    - (id)init {
        if ([super init] == nil)
            return nil;

        return self;
    }

    - (id)retain {
        return self;
    }

    - (unsigned)retainCount {
        return UINT_MAX;
    }

    //- (void)release {
        // Do nothing.
    //}

    - (id)autorelease {
        return self;
    }


@end

我的问题是：我需要把你发布的这段代码放在这个问题的解决方案上。。。我怎么能解决这个问题？

Answer 4

现在Unity 3.5已经添加了对Microphone输入的支持，我建议您在Unity中执行此操作，这样您就不必维护Cocoa代码并轻松将其移植到Android / Web / Native在将来。

已经有一些有用的帖子：

http://forum.unity3d.com/threads/123036-iOS-Microphone-input

http://forum.unity3d.com/threads/118215-Blow-detection-(Using-iOS-Microphone）

如何使用Unity和IOS检测麦克风中的击打

4 个答案: