wavをauに変換する

'wav2au
#console
#include<vcrt71.sbp>

Const infile = "test.wav"
Const outfile = "test.au"

Type AUHEADER
    snd[3] As Byte'".snd"
    hdrsiz  As DWord'ヘッダサイズ
    datsiz  As DWord'データのサイズ
    fmt  As DWord'フォーマット
    rate As DWord'サンプリングレート
    ch As DWord'チャンネル数
End Type

Type WAVEHEADER
    RIFF[3] As Byte'"RIFF"
    bytes As DWord'(ファイルのバイト数)-8
    WAVE[3] As Byte' "WAVE"
    fmt[3] As Byte '"fmt " 
    siz_wf As DWord'PCMWAVEFORMAT構造体のバイト数=常に16
    'PCMWAVEFORMAT構造
    wFormatTag As Word 'pcm=1
    nChannels As  Word 'ch数
    nSamplesPerSec As Dword 'サンプリング周波数
    nAvgBytesPerSec As  DWord
    nBlockAlign As Word
    wBitsPerSample As Word '量子化数
    data[3] As Byte'"data"
    pcmbytes As DWord'波形データのバイト数
End Type 

'エンディアン変換(4バイト)
Sub swap4(d As BytePtr)
    Dim tmp As Byte

    tmp = GetByte(d)
    SetByte(d , GetByte(d+3))
    SetByte(d+3 , tmp)

    tmp = GetByte(d+1)
    SetByte(d+1 , GetByte(d+2))
    SetByte(d+2 , tmp)
End Sub

'エンディアン変換(2バイト)
Sub swap2(d As BytePtr)
    Dim tmp As Byte

    tmp = GetByte(d)
    SetByte(d , GetByte(d+1))
    SetByte(d+1 , tmp)
End Sub

Dim wh As WAVEHEADER
Dim ah As AUHEADER
Dim ifp As *FILE
DIm ofp As *FILE
Dim  pcm As BytePtr
Dim n As DWord

'ファイルを開く
ifp = fopen("test.wav" , "rb")
if(ifp = NULL) Then exit(0)
ofp = fopen("test.au" , "wb")
if(ofp = NULL) Then     exit(0)
fread(VarPtr(wh) , sizeof(WAVEHEADER) , 1 , ifp)

'auヘッダを作ってみる
lstrcpy(ah.snd , ".snd")
ah.hdrsiz = 24
ah.datsiz =wh.pcmbytes
ah.fmt = 3
ah.rate =wh.nSamplesPerSec
ah.ch = wh.nChannels

'ここでエンディアン変換
swap4(VarPtr(ah.hdrsiz))
swap4(VarPtr(ah.datsiz))
swap4(VarPtr(ah.fmt))
swap4(VarPtr(ah.rate))
swap4(VarPtr(ah.ch))

fwrite(VarPtr(ah) , sizeof(AUHEADER) , 1 , ofp)

pcm = malloc(wh.pcmbytes)
fread(pcm , 1 , wh.pcmbytes , ifp)

'pcmのエンディアンを変換
For n=0 To wh.pcmbytes Step 2
    swap2(VarPtr(pcm[n]))
Next
fwrite(pcm , 1 , wh.pcmbytes , ofp)

free(pcm)
fclose(ifp)
fclose(ofp)

exit(0)'終わり