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这是Unity 3D游戏引擎的代码...

我尝试使用此源脚本监控声音分贝，但为什么我得到负分贝？

理论上，正常对话的声音会产生60db，即使是安静的房间也会产生 10-20dB ...

任何想法 ？

分贝计算结果：

在此处输入图像描述

以下是源代码：

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class VR_SoundMonitor : MonoBehaviour 
{

    public float DecibleValue;
    public float RmsValue;  
    public float PitchValue; 
    private AudioSource audioSourceObject; 
    private float[] _spectrum;
    private float[] _samples;
    private float _fSample;
    const int QSamples = 1024;
    const float RefValue = 0.1f;
    const float Threshold = 0.02f;

    void Start () 
    {
        audioSourceObject = GetComponent<AudioSource> ();
        InitVariable ();
        InitMicrophone ();
    }

    //Nyalakan Microphone
    private void InitMicrophone()
    { 
        audioSourceObject.clip = Microphone.Start ("SoundMonitoring", false, 60, 44100);
        while (!(Microphone.GetPosition(null) > 0)) { }     
        audioSourceObject.Play();
    }

    private void InitVariable()
    {
        _samples = new float[QSamples]; //use constanta (3 below)
        _spectrum = new float[QSamples];
        _fSample = AudioSettings.outputSampleRate;
    }

    void Update () 
    {
        CalculateAnalyzeSound (audioSourceObject);
        Debug.Log ("Decibels="+DecibleValue+" ## RmsVal="+RmsValue);
    }

    public void CalculateAnalyzeSound(AudioSource audio)
    {
        float _RmsValue;
        float _DbValue;
        float _PitchValue;

        audio.GetOutputData(_samples, 0);
        int i = 0;
        float sum = 0;

        for (i = 0; i < QSamples; i++)
        {
         sum += _samples[i] * _samples[i]; // sum squared samples
        }

        _RmsValue = Mathf.Sqrt(sum / QSamples); // rms = square root of average
        _DbValue = 20 * Mathf.Log10(_RmsValue / RefValue); // calculate dB
        if (_DbValue < -160) _DbValue = -160; // clamp it to -160dB min

        RmsValue = _RmsValue;
        DecibleValue = _DbValue;
    }
}

怎么了 ？有什么想法，请告诉我......

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