我有一个小问题:在VS2010年的“WinForm App”中, 我试图做Alvas.Audio似乎可行的工作。见(c#ex:http://alvas.net/alvas.audio.tips.aspx#tip94 。

 Dim data() As Byte = wr.ReadData(second * i, second)

结果给了我 data. long ()=0 。 我没有任何例外, 我可以读取它的格式, 无论我使用什么读者, 我都有这个问题 。

EDIT : 经过一些测试后, 第一步我创建的未压缩文件( 以PCM格式, 有. wav 扩展) 似乎无法被 Alvas. audio 库确认为第二步 。 我必须忽略音频文件标记或类似的东西 。

以下是可能来源的代码(基本上这是第1步):

    Dim functOut As String = String.Empty
    Dim wr As Alvas.Audio.IAudioReader = Nothing
    Dim fs As IO.FileStream = Nothing
    Dim i As Integer = 0
    Dim tmpData() As Byte = Nothing
    Dim dataPCM() As Byte = Nothing
    Dim newFormat As IntPtr = IntPtr.Zero
    Try
        Select Case IO.Path.GetExtension(filename).ToLower()
            Case ".wav"
                wr = New Alvas.Audio.WaveReader(IO.File.OpenRead(filename))
                filename = IO.Path.GetTempPath & IO.Path.GetFileNameWithoutExtension(filename) & "2" & IO.Path.GetExtension(filename)
            Case ".mp3"
                wr = New Alvas.Audio.Mp3Reader(IO.File.OpenRead(filename))
            Case Else : wr = New Alvas.Audio.DsReader(filename)
        End Select

        functOut = IO.Path.ChangeExtension(filename, ".wav")

        Dim format As IntPtr = wr.ReadFormat()
        Dim formatDetail As Alvas.Audio.WaveFormat = Alvas.Audio.AudioCompressionManager.GetWaveFormat(format)


        If formatDetail.wFormatTag = Alvas.Audio.AudioCompressionManager.MpegLayer3FormatTag Then
            Alvas.Audio.AudioCompressionManager.Mp3ToWav(filename, functOut)
            Return True
        Else
            IO.File.Create(functOut).Close()
            While True
                tmpData = wr.ReadData(SECONDS * i, SECONDS)
                If tmpData Is Nothing Or tmpData.Length = 0 Then Exit While

                If formatDetail.wBitsPerSample < 16 Then
                    Alvas.Audio.AudioCompressionManager.ToPcm16Bit(format, tmpData, newFormat, dataPCM)
                Else 
                    newFormat = format
                    dataPCM = tmpData
                End If

                formatDetail = Alvas.Audio.AudioCompressionManager.GetWaveFormat(newFormat)

                fs = IO.File.Open(filename, IO.FileMode.Append, IO.FileAccess.Write)
                Using ww As New Alvas.Audio.WaveWriter(fs, Alvas.Audio.AudioCompressionManager.FormatBytes(newFormat))
                    ww.Write(dataPCM, 0, dataPCM.Length())
                End Using

                i += 1
                tmpData = Nothing
            End While
            Return True
        End If

        wr.Close()
    Catch ex As Exception
        filename = String.Empty
        Throw ex
    Finally
        fs.Close()
        wr.Close()
        filename = functOut
        GC.Collect()
    End Try

我如何写出结果流以确保我稍后能再读一遍?

任何想法都将受到高度赞赏。