音频文件解析(一)：WAV格式文件头部解析

　　WAV为微软公司(Microsoft)开发的一种声音文件格式,它符合RIFF(Resource Interchange File Format)文件规范,用于保存Windows平台的音频信息资源.

2.格式化块(Format-Chunk)

3.附加块(Fact-Chunk) *当前块偏移地址需要根据实际数据变更

4.数据块(Data-Chunk) *当前块偏移地址需要根据实际数据变更

    Structure waveHeaderStructre
        ‘RiffChunk
        Dim RIFF As String
        Dim FileSize As UInteger
        Dim WAVE As String
        ‘FormatChunk
        Dim FORMAT As String
        Dim FormatSize As UInteger
        Dim FilePadding As UShort
        Dim FormatChannels As UShort
        Dim SamplesPerSecond As UInteger
        Dim AverageBytesPerSecond As UInteger
        Dim BytesPerSample As UShort
        Dim BitsPerSample As UShort
        Dim FormatExtra As UShort
        ‘FactChunk
        Dim FACT As String
        Dim FactSize As UInteger
        Dim FactInf As UInteger
        ‘DataChunk
        Dim DATA As String
        Dim DataSize As UInteger
    End Structure

1.打开一个wav文件

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

2.头部信息解析

  Public Sub SplitWaveData(ByVal data As Byte()) ‘提取wav文件头部信息
        Dim tempIndex As UShort = 0
        waveHeadInf.RIFF = CType(System.Text.Encoding.ASCII.GetChars(data, 0, 4), String)
        waveHeadInf.FileSize = System.BitConverter.ToUInt32(data, 4)
        waveHeadInf.WAVE = CType(System.Text.Encoding.ASCII.GetChars(data, 8, 4), String)
        ‘FormatChunk
        waveHeadInf.FORMAT = CType(System.Text.Encoding.ASCII.GetChars(data, 12, 4), String)
        waveHeadInf.FormatSize = System.BitConverter.ToUInt32(data, 16)
        waveHeadInf.FilePadding = System.BitConverter.ToUInt16(data, 20)
        waveHeadInf.FormatChannels = System.BitConverter.ToUInt16(data, 22)
        waveHeadInf.SamplesPerSecond = System.BitConverter.ToUInt32(data, 24)
        waveHeadInf.AverageBytesPerSecond = System.BitConverter.ToUInt32(data, 28)
        waveHeadInf.BytesPerSample = System.BitConverter.ToUInt16(data, 32)
        waveHeadInf.BitsPerSample = System.BitConverter.ToUInt16(data, 34)
        If waveHeadInf.FormatSize = 18 Then
            waveHeadInf.FormatExtra = System.BitConverter.ToUInt16(data, 36)
        Else
            waveHeadInf.FormatExtra = 0
        End If
        tempIndex = 20 + waveHeadInf.FormatSize
        ‘FactChunk
        waveHeadInf.FACT = CType(System.Text.Encoding.ASCII.GetChars(data, tempIndex, 4), String)
        If waveHeadInf.FACT = "fact" Then
            waveHeadInf.FactSize = System.BitConverter.ToUInt32(data, tempIndex + 4)
            waveHeadInf.FactInf = IIf(waveHeadInf.FactSize = 2, System.BitConverter.ToUInt16(data, tempIndex + 8), System.BitConverter.ToUInt32(data, tempIndex + 8))
            tempIndex = tempIndex + waveHeadInf.FactSize + 8
        Else
            waveHeadInf.FACT = "NULL"
            waveHeadInf.FactSize = 0
            waveHeadInf.FactInf = 0
        End If
        ‘DataChunk
        waveHeadInf.DATA = CType(System.Text.Encoding.ASCII.GetChars(data, tempIndex, 4), String)
        waveHeadInf.DataSize = System.BitConverter.ToUInt32(data, tempIndex + 4)
        ShowWaveHeadInf()
    End Sub

3.ListView显示头部信息

    Public Sub ShowWaveHeadInf() ‘显示wav文件详细信息
        Dim Chunks As New List(Of String)
        Chunks.Add("RIFF标志-" & waveHeadInf.RIFF)
        Chunks.Add("文件长度-" & Hex(waveHeadInf.FileSize))
        Chunks.Add("WAVE标志-" & waveHeadInf.WAVE)
        ‘
        Chunks.Add("FORMAT标志-" & waveHeadInf.FORMAT)
        Chunks.Add("Format长度-" & Hex(waveHeadInf.FormatSize))
        Chunks.Add("编码方式-" & Hex(waveHeadInf.FilePadding))
        Chunks.Add("声道数目-" & Hex(waveHeadInf.FormatChannels))
        Chunks.Add("采样频率-" & Hex(waveHeadInf.SamplesPerSecond))
        Chunks.Add("每秒所需字节数-" & Hex(waveHeadInf.AverageBytesPerSecond))
        Chunks.Add("数据块对齐单位-" & Hex(waveHeadInf.BytesPerSample))
        Chunks.Add("采样所需Bit数-" & Hex(waveHeadInf.BitsPerSample))
        Chunks.Add("附加信息-" & waveHeadInf.FormatExtra)
        ‘
        Chunks.Add("FACT标志-" & waveHeadInf.FACT)
        Chunks.Add("FACT长度-" & Hex(waveHeadInf.FactSize))
        Chunks.Add("FACT信息-" & waveHeadInf.FactInf)
        ‘
        Chunks.Add("DATA标志-" & waveHeadInf.DATA)
        Chunks.Add("DATA长度-" & Hex(waveHeadInf.DataSize))
        InfForm.ListView1.Items.Clear()
        For Each stringlist In Chunks
            ListView1.Items.Add(Split(stringlist, "-")(0))
            ListView1.Items(ListView1.Items.Count - 1).SubItems.Add(Split(stringlist, "-")(1))
        Next
    End Sub