Question

我使用＆gt; Xcode版本9.2 ＆lt;
我使用＆gt; AudioKit版本4.0.4 ＆lt;

我已经编写了一些您可以在下面找到的代码

播放特定声音(frequency: 500.0HZ)
＆＃34;听＆＃34;麦克风输入和实时计算频率

如果我正在呼叫playSound()或receiveSound()，那么一切看起来都很好，并且确实按照我的预期运作。但之后调用了playSound()和receiveSound()？正是在那里我遇到了很多问题。

这就是我希望代码正常运行的方式：

SystemClass.playSound() //play sound
DispatchQueue.main.asyncAfter(deadline: (DispatchTime.now() + 3.0)) {
   SystemClass.receiveSound() //get microphone input 3 seconds later
}

let SystemClass: System = System()
class System {
    public init() { }

    func playSound() {
        let sound = AKOscillator()
        AudioKit.output = sound
        AudioKit.start()
        sound.frequency = 500.0
        sound.amplitude = 0.5
        sound.start()
        DispatchQueue.main.asyncAfter(deadline: (DispatchTime.now() + 2.0)) {
            sound.stop()
        }
    }


    var tracker: AKFrequencyTracker!
    func receiveSound() {
        AudioKit.stop()
        AKSettings.audioInputEnabled = true
        let mic = AKMicrophone()
        tracker = AKFrequencyTracker(mic)
        let silence = AKBooster(tracker, gain: 0)
        AudioKit.output = silence
        AudioKit.start()
        Timer.scheduledTimer( timeInterval: 0.1, target: self, selector: #selector(SystemClass.outputFrequency), userInfo: nil, repeats: true)
    }

    @objc func outputFrequency() {
        print("Frequency: \(tracker.frequency)")
    }
}

这些消息是我每次想要运行代码时调用的一些编译器错误消息（调用playSound()并在3秒后调用receiveSound ()）：

AVAEInternal.h:103:_AVAE_CheckNoErr: [AVAudioEngineGraph.mm:1266:Initialize: (err = AUGraphParser::InitializeActiveNodesInOutputChain(ThisGraph, kOutputChainOptimizedTraversal, *GetOutputNode(), isOutputChainActive)): error -10875

AVAudioEngine.mm:149:-[AVAudioEngine prepare]: Engine@0x1c401bff0: could not initialize, error = -10875

[MediaRemote] [AVOutputContext] WARNING: AVF context unavailable for sharedSystemAudioContext

[AVAudioEngineGraph.mm:1266:Initialize: (err = AUGraphParser::InitializeActiveNodesInOutputChain(ThisGraph, kOutputChainOptimizedTraversal, *GetOutputNode(), isOutputChainActive)): error -10875

Fatal error: AudioKit: Could not start engine. error: Error 

Domain=com.apple.coreaudio.avfaudio Code=-10875 "(null)" UserInfo={failed call=err = AUGraphParser::InitializeActiveNodesInOutputChain(ThisGraph, kOutputChainOptimizedTraversal, *GetOutputNode(), isOutputChainActive)}.: file /Users/megastep/src/ak/AudioKit/AudioKit/Common/Internals/AudioKit.swift, line 243

Answer 1

我相信您的问题的狮子会分享是由于在使用它们的函数中本地声明AKNode：

   let sound = AKOscillator()
   let mic = AKMicrophone()        
   let silence = AKBooster(tracker, gain: 0)

将这些声明为实例变量，如here所述。

斯威夫特：声音输出＆amp;麦克风输入|使用AudioKit |

1 个答案: