如何根据 .NET 程序从用户输入和数学函数生成的波形数据播放声音?
“波形数据”是指固定间隔时间序列(可能为 44.1 kHz)中的 SPL(声压级)值。我认为这需要某种流缓冲安排。
请注意,这必须是实时/实时的,因此仅创建一个 .wav 文件然后播放是不够的。VB.NET 是首选,但 C# 也是可以接受的。
澄清一下:我正在寻找的是一个简单的工作代码示例。
您可以使用NAudio做到这一点。您创建一个派生自 WaveStream 的流,并在其重写的 Read 方法中返回您可以即时生成的样本。您可以控制声卡使用的缓冲区大小,从而控制延迟。
PlayerEx pl = new PlayerEx();
private static void PlayArray(PlayerEx pl)
{
double fs = 8000; // sample freq
double freq = 1000; // desired tone
short[] mySound = new short[4000];
for (int i = 0; i < 4000; i++)
{
double t = (double)i / fs; // current time
mySound[i] = (short)(Math.Cos(t * freq) * (short.MaxValue));
}
IntPtr format = AudioCompressionManager.GetPcmFormat(1, 16, (int)fs);
pl.OpenPlayer(format);
byte[] mySoundByte = new byte[mySound.Length * 2];
Buffer.BlockCopy(mySound, 0, mySoundByte, 0, mySoundByte.Length);
pl.AddData(mySoundByte);
pl.StartPlay();
}
查看此线程,了解如何使用任意数据加载DirectSound缓冲区并进行播放。
每条评论:是的,我知道。您需要将 C++ 翻译成 C# 或 VB.NET。但是,概念才是最重要的。您创建一个辅助 DirectSound 缓冲区,然后使用它流式传输到您的主缓冲区并播放。
我认为您需要为此使用DirectSound(DirectX API)。它适用于您可以用生成的数据填充的缓冲区。
我有这个代码,但你必须有代码才能在内存中生成你的 wav 文件。
Option Strict Off
Option Explicit On
Imports Microsoft.DirectX.DirectSound
Imports Microsoft.DirectX
Imports System.Threading
Public Class Form1
Const SRATE As Integer = 44100
Const FREQ As Integer = 440
Const DUR As Integer = 1
Private dsDesc As BufferDescription
Private wvFormat As WaveFormat
Private DS As Device
Dim SecondaryBuffer As Microsoft.DirectX.DirectSound.SecondaryBuffer
Dim BufferDescription As Microsoft.DirectX.DirectSound.BufferDescription
Dim DXFormat As Microsoft.DirectX.DirectSound.WaveFormat
Dim sbuf(DUR * SRATE) As Short
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
Show()
DS = New Microsoft.DirectX.DirectSound.Device
DS.SetCooperativeLevel(Me, CooperativeLevel.Normal)
wvFormat.FormatTag = WaveFormatTag.Pcm
wvFormat.Channels = 1
wvFormat.SamplesPerSecond = SRATE
wvFormat.BitsPerSample = 16
wvFormat.AverageBytesPerSecond = 2 * SRATE
wvFormat.BlockAlign = 2
dsDesc = New BufferDescription(wvFormat)
dsDesc.BufferBytes = 2 * DUR * SRATE
dsDesc.Flags = 0
Dim buff1 = PlayWave(400)
Dim buff2 = PlayWave(600)
buff1 = PlayWave(400)
buff1.Play(0, Microsoft.DirectX.DirectSound.BufferPlayFlags.Default)
Thread.Sleep(1000)
buff1 = PlayWave(600)
buff1.Play(0, Microsoft.DirectX.DirectSound.BufferPlayFlags.Default)
' End
End Sub
Function PlayWave(FREQ As Integer) As SecondaryBuffer
' create a buffer
Dim dsBuffer As SecondaryBuffer
dsBuffer = New SecondaryBuffer(dsDesc, DS)
Dim sbuf(DUR * SRATE) As Short
' create tone
For i As Integer = 0 To DUR * SRATE
sbuf(i) = CShort(10000 * Math.Sin(2 * Math.PI * FREQ * i / SRATE))
Next
' copy to buffer
dsBuffer.Write(0, sbuf, LockFlag.EntireBuffer)
Return dsBuffer
End Function