简介
WAV 为微软开发的一种vb.net教程声音文件格式,它符合 RIFF(Resource Interchange File Format)文件规范,用于保存 Windows 平台c#教程的音频信息资源。
第一节 文件头部格式
文件头(Header)是位于文件python基础教程开头的一段承担一定任务的数据,通常是对主体数据的描述。
WAV 文件头由java基础教程哪几部分构成
RIFF块(RIFF-Chunk)
格式化块(Format-Chunk)
附加块(Fact-Chunk)块偏移sql教程地址需要根据实际数据变更
数据块(Data-Chunk)块偏移地址需要根据实际数据变更
| 偏移地址 | 字节数 | 数据类型 | 内容 | 
| &H00 | 4 | String | 'RIFF'文件标志 | 
| &H04 | 4 | UInteger | 文件总长 | 
| &H08 | 4 | String | 'WAVE'文件标志 | 
表1-1 RIFF块(RIFF-Chunk)
| 偏移地址 | 字节数 | 数据类型 | 内容 | 
| &H0C | 4 | String | 'fmt'标志 | 
| &H10 | 4 | UInteger | 块长度 | 
| &H12 | 2 | UShort | PCM格式类别 | 
| &H14 | 2 | UShort | 声道数目 | 
| &H18 | 4 | UInteger | 采样率 | 
| &H1C | 4 | UInteger | 传输速率 | 
| &H1E | 2 | UShort | 数据块对齐 | 
| &H20 | 2 | UShort | 每样本bit数 | 
| &H22 | 2 | UShort | 可选 | 
表1-2 格式化块(Format-Chunk)
| 偏移地址 | 字节数 | 数据类型 | 内容 | 
| &H26 | 4 | String | 'fact'标志 | 
| &H2A | 4 | UInteger | 块长度 | 
| &H2E | 4 | UInteger | 附加信息 | 
表1-3 附加块(Fact-Chunk)
| 偏移地址 | 字节数 | 数据类型 | 内容 | 
| &H32 | 4 | String | 'data'文件标志 | 
| &H36 | 4 | UInteger | 数据块总长 | 
表1-4 数据块(Data-Chunk)
第二节 代码实现
1. 构建一个 WaveHeader 结构体


''' <summary>
''' wav音频头部信息
''' </summary>
Public Structure WaveHeader
#Region "RiffChunk"
    ''' <summary>
    ''' RIFF标志
    ''' </summary>
    Dim RIFF As String
    ''' <summary>
    ''' 文件长度
    ''' </summary>
    Dim FileSize As UInteger
    ''' <summary>
    ''' WAVE标志
    ''' </summary>
    Dim WAVE As String
#End Region
#Region "FormatChunk"
    ''' <summary>
    ''' FORMAT标志
    ''' </summary>
    Dim FORMAT As String
    ''' <summary>
    ''' Format长度
    ''' </summary>
    Dim FormatSize As UInteger
    ''' <summary>
    ''' 编码方式
    ''' </summary>
    Dim FilePadding As UShort
    ''' <summary>
    ''' 声道数目
    ''' </summary>
    Dim FormatChannels As UShort
    ''' <summary>
    ''' 采样频率
    ''' </summary>
    Dim SamplesPerSecond As UInteger
    ''' <summary>
    ''' 每秒所需字节数
    ''' </summary>
    Dim AverageBytesPerSecond As UInteger
    ''' <summary>
    ''' 数据块对齐单位
    ''' </summary>
    Dim BytesPerSample As UShort
    ''' <summary>
    ''' 单个采样所需Bit数
    ''' </summary>
    Dim BitsPerSample As UShort
    ''' <summary>
    ''' 附加信息
    ''' </summary>
    Dim FormatExtra As UShort
#End Region
#Region "FactChunk"
    ''' <summary>
    ''' FACT标志
    ''' </summary>
    Dim FACT As String
    ''' <summary>
    ''' Fact长度
    ''' </summary>
    Dim FactSize As UInteger
    ''' <summary>
    ''' Fact信息
    ''' </summary>
    Dim FactInf As UInteger
#End Region
#Region "DataChunk"
    ''' <summary>
    ''' DATA标志
    ''' </summary>
    Dim DATA As String
    ''' <summary>
    ''' Data长度
    ''' </summary>
    Dim DataSize As UInteger
#End Region
End Structure 



/// <summary>
/// wav音频头部信息
/// </summary>
public struct WaveHeader
{
    #region "RiffChunk"
    /// <summary>
    /// RIFF标志
    /// </summary>
    public string RIFF;
    /// <summary>
    /// 文件长度
    /// </summary>
    public uint FileSize;
    /// <summary>
    /// WAVE标志
    /// </summary>
        #endregion
    public string WAVE;
    #region "FormatChunk"
    /// <summary>
    /// FORMAT标志
    /// </summary>
    public string FORMAT;
    /// <summary>
    /// Format长度
    /// </summary>
    public uint FormatSize;
    /// <summary>
    /// 编码方式
    /// </summary>
    public ushort FilePadding;
    /// <summary>
    /// 声道数目
    /// </summary>
    public ushort FormatChannels;
    /// <summary>
    /// 采样频率
    /// </summary>
    public uint SamplesPerSecond;
    /// <summary>
    /// 每秒所需字节数
    /// </summary>
    public uint AverageBytesPerSecond;
    /// <summary>
    /// 数据块对齐单位
    /// </summary>
    public ushort BytesPerSample;
    /// <summary>
    /// 单个采样所需Bit数
    /// </summary>
    public ushort BitsPerSample;
    /// <summary>
    /// 附加信息
    /// </summary>
        #endregion
    public ushort FormatExtra;
    #region "FactChunk"
    /// <summary>
    /// FACT标志
    /// </summary>
    public string FACT;
    /// <summary>
    /// Fact长度
    /// </summary>
    public uint FactSize;
    /// <summary>
    /// Fact信息
    /// </summary>
        #endregion
    public uint FactInf;
    #region "DataChunk"
    /// <summary>
    /// DATA标志
    /// </summary>
    public string DATA;
    /// <summary>
    /// Data长度
    /// </summary>
        #endregion
    public uint DataSize;
} 

2. 打开 *.wav 二进制文件

Dim data() As Byte = My.Computer.FileSystem.ReadAllBytes(wavFileName)

byte[] data = System.IO.File.ReadAllBytes(wavFileName);
3. 文件头部信息解析


    ''' <summary>
    ''' 返回指定字节数组包含的Wave头部信息
    ''' </summary>
    Public Function GetWaveHeaderFromBytes(data As Byte()) As WaveHeader
        Dim header As New WaveHeader
        Dim tempIndex As UShort = 0
        header.RIFF = CType(System.Text.Encoding.ASCII.GetChars(data, 0, 4), String)
        header.FileSize = System.BitConverter.ToUInt32(data, 4)
        header.WAVE = CType(System.Text.Encoding.ASCII.GetChars(data, 8, 4), String)
        'FormatChunk
        header.FORMAT = CType(System.Text.Encoding.ASCII.GetChars(data, 12, 4), String)
        header.FormatSize = System.BitConverter.ToUInt32(data, 16)
        header.FilePadding = System.BitConverter.ToUInt16(data, 20)
        header.FormatChannels = System.BitConverter.ToUInt16(data, 22)
        header.SamplesPerSecond = System.BitConverter.ToUInt32(data, 24)
        header.AverageBytesPerSecond = System.BitConverter.ToUInt32(data, 28)
        header.BytesPerSample = System.BitConverter.ToUInt16(data, 32)
        header.BitsPerSample = System.BitConverter.ToUInt16(data, 34)
        If header.FormatSize = 18 Then
            header.FormatExtra = System.BitConverter.ToUInt16(data, 36)
        Else
            header.FormatExtra = 0
        End If
        tempIndex = 20 + header.FormatSize
        'FactChunk
        header.FACT = CType(System.Text.Encoding.ASCII.GetChars(data, tempIndex, 4), String)
        If header.FACT = "fact" Then
            header.FactSize = System.BitConverter.ToUInt32(data, tempIndex + 4)
            header.FactInf = IIf(header.FactSize = 2, System.BitConverter.ToUInt16(data, tempIndex + 8), System.BitConverter.ToUInt32(data, tempIndex + 8))
            tempIndex = tempIndex + header.FactSize + 8
        Else
            header.FACT = "NULL"
            header.FactSize = 0
            header.FactInf = 0
        End If
        'DataChunk
        header.DATA = CType(System.Text.Encoding.ASCII.GetChars(data, tempIndex, 4), String)
        header.DataSize = System.BitConverter.ToUInt32(data, tempIndex + 4)
        Return header
    End Function 



/// <summary>
/// 返回指定字节数组包含的Wave头部信息
/// </summary>
public WaveHeader GetWaveHeaderFromBytes(byte[] data)
{
    WaveHeader header = new WaveHeader();
    ushort tempIndex = 0;
    header.RIFF = Convert.ToString(System.Text.Encoding.ASCII.GetChars(data, 0, 4));
    header.FileSize = System.BitConverter.ToUInt32(data, 4);
    header.WAVE = Convert.ToString(System.Text.Encoding.ASCII.GetChars(data, 8, 4));
    //FormatChunk
    header.FORMAT = Convert.ToString(System.Text.Encoding.ASCII.GetChars(data, 12, 4));
    header.FormatSize = System.BitConverter.ToUInt32(data, 16);
    header.FilePadding = System.BitConverter.ToUInt16(data, 20);
    header.FormatChannels = System.BitConverter.ToUInt16(data, 22);
    header.SamplesPerSecond = System.BitConverter.ToUInt32(data, 24);
    header.AverageBytesPerSecond = System.BitConverter.ToUInt32(data, 28);
    header.BytesPerSample = System.BitConverter.ToUInt16(data, 32);
    header.BitsPerSample = System.BitConverter.ToUInt16(data, 34);
    if (header.FormatSize == 18) {
        header.FormatExtra = System.BitConverter.ToUInt16(data, 36);
    } else {
        header.FormatExtra = 0;
    }
    tempIndex = 20 + header.FormatSize;
    //FactChunk
    header.FACT = Convert.ToString(System.Text.Encoding.ASCII.GetChars(data, tempIndex, 4));
    if (header.FACT == "fact") {
        header.FactSize = System.BitConverter.ToUInt32(data, tempIndex + 4);
        header.FactInf = (header.FactSize == 2 ? System.BitConverter.ToUInt16(data, tempIndex + 8) : System.BitConverter.ToUInt32(data, tempIndex + 8));
        tempIndex = tempIndex + header.FactSize + 8;
    } else {
        header.FACT = "NULL";
        header.FactSize = 0;
        header.FactInf = 0;
    }
    //DataChunk
    header.DATA = Convert.ToString(System.Text.Encoding.ASCII.GetChars(data, tempIndex, 4));
    header.DataSize = System.BitConverter.ToUInt32(data, tempIndex + 4);
    return header;
} 


                

















