Audiokit记录-55：例外（-1）：“”-反复

Question

我更新到了最新版本的Audiokit 4.5，现在正在打印要收听麦克风振幅的Audiokit类：55：控制台上的EXCEPTION（-1）：“”无限。该应用程序不会崩溃或发生任何事情。

我的应用程序是一个使用GPUImage库记录的摄像机应用程序。仅当由于某种原因开始录制时，日志才会显示。

在此之上。我的onAmplitudeUpdate回调方法不再输出任何内容，仅输出0.0个值。在更新Audiokit之前没有发生这种情况。这里有什么想法吗？

这是我的课：

//  G8Audiokit.swift
//  GenerateToolkit
//
//  Created by Omar Juarez Ortiz on 2017-08-03.
//  Copyright © 2017 All rights reserved.
//

import Foundation
import AudioKit

class G8Audiokit{

    //Variables for Audio audioAnalysis
    var microphone: AKMicrophone! // Device Microphone
    var amplitudeTracker: AKAmplitudeTracker! // Tracks the amplitude of the microphone
    var signalBooster: AKBooster! // boosts the signal
    var audioAnalysisTimer: Timer? // Continuously calls audioAnalysis function
    let amplitudeBuffSize = 10 // Smaller buffer will yield more amplitude responiveness and instability, higher value will respond slower but will be smoother
    var amplitudeBuffer: [Double] // This stores a rolling window of amplitude values, used to get average amplitude

    public var onAmplitudeUpdate: ((_ value: Float) -> ())?

    static let sharedInstance = G8Audiokit()

    private init(){ //private because that way the class can only be initialized by itself.
        self.amplitudeBuffer = [Double](repeating: 0.0, count: amplitudeBuffSize)
        startAudioAnalysis()

    }
//    public override init() {
//        // Initialize the audio buffer with zeros
//
//    }
    /**
     Set up AudioKit Processing Pipeline and start the audio analysis.
     */
    func startAudioAnalysis(){

        stopAudioAnalysis()

        // Settings
        AKSettings.bufferLength = .medium // Set's the audio signal buffer size
        do {
            try AKSettings.setSession(category: .playAndRecord)
        } catch {
            AKLog("Could not set session category.")
        }

        // ----------------
        // Input + Pipeline

        // Initialize the built-in Microphone
        microphone = AKMicrophone()

        // Pre-processing
        signalBooster = AKBooster(microphone)
        signalBooster.gain = 5.0 // When video recording starts, the signal gets boosted to the equivalent of 5.0, so we're setting it to 5.0 here and changing it to 1.0 when we start video recording.

        // Filter out anything outside human voice range
        let highPass = AKHighPassFilter(signalBooster, cutoffFrequency: 55) // Lowered this a bit to be more sensitive to bass-drums
        let lowPass = AKLowPassFilter(highPass, cutoffFrequency: 255)
        //  At this point you don't have much signal left, so you balance it against the original signal!
        let rebalanced = AKBalancer(lowPass, comparator: signalBooster)

        // Track the amplitude of the rebalanced signal, we use this value for audio reactivity
        amplitudeTracker = AKAmplitudeTracker(rebalanced)

        // Mute the audio that gets routed to the device output, preventing feedback
        let silence = AKBooster(amplitudeTracker, gain:0)

        // We need to complete the chain, routing silenced audio to the output
        AudioKit.output = silence

        // Start the chain and timer callback
        do{ try AudioKit.start(); }
        catch{}

        audioAnalysisTimer = Timer.scheduledTimer(timeInterval: 0.01,
                                                  target: self,
                                                  selector: #selector(audioAnalysis),
                                                  userInfo: nil,
                                                  repeats: true)
        // Put the timer on the main thread so UI updates don't interrupt
        RunLoop.main.add(audioAnalysisTimer!, forMode: RunLoopMode.commonModes)
    }

    // Call this when closing the app or going to background
    public func stopAudioAnalysis(){
        audioAnalysisTimer?.invalidate()
        AudioKit.disconnectAllInputs() // Disconnect all AudioKit components, so they can be relinked when we call startAudioAnalysis()
    }

    // This is called on the audioAnalysisTimer
    @objc func audioAnalysis(){
        writeToBuffer(val: amplitudeTracker.amplitude) // Write an amplitude value to the rolling buffer
        let val = getBufferAverage()
        onAmplitudeUpdate?(Float(val))

    }

    // Writes amplitude values to a rolling window buffer, writes to index 0 and pushes the previous values to the right, removes the last value to preserve buffer length.
    func writeToBuffer(val: Double) {
        for (index, _) in amplitudeBuffer.enumerated() {
            if (index == 0) {
                amplitudeBuffer.insert(val, at: 0)
                _ = amplitudeBuffer.popLast()
            }
            else if (index < amplitudeBuffer.count-1) {
                amplitudeBuffer.rearrange(from: index-1, to: index+1)
            }
        }
    }

    // Returns the average of the amplitudeBuffer, resulting in a smoother audio reactivity signal
    func getBufferAverage() -> Double {
        var avg:Double = 0.0
        for val in amplitudeBuffer {
            avg = avg + val
        }
        avg = avg / amplitudeBuffer.count
        return avg
    }



}