window 音频接口调用的例子

 以下是windows 音频接口调用的例子，可以在vc 或minGW下编译，需要借助库文件libwinmm.a

 

//#include "stdafx.h"
#include <windows.h>
#include <math.h>
#include <mmsystem.h>
#include <stdio.h>
#include <stdlib.h>

#define PI 3.14159
#define SAMPLE_RATE      11025
#define OUT_BUFFER_SIZE     4096

static PBYTE                 pBuffer1, pBuffer2 ;
static PWAVEHDR              pWaveHdr1, pWaveHdr2 ;
static WAVEFORMATEX          waveformat ;

HWAVEOUT hWaveOut;

void FillBuffer(unsigned char * buffer,int iFreq)
{

 static double         fAngle ;
 int                   i ;

 for (i = 0 ; i < OUT_BUFFER_SIZE ; i++)
 {
  buffer [i] = (char)(127 + 127 * sin (fAngle)) ;
  fAngle += 2 * PI * iFreq / SAMPLE_RATE ;
  if (   fAngle > 2 * PI)
   fAngle -= 2 * PI ;
 }

}

int CALLBACK waveOutProc
(
HWAVEOUT hWaveOut,
UINT uMsg,
DWORD dwInstance,
DWORD dwParam1,
DWORD dwParam2
)
{
 static int iFreq=400;
 LPWAVEHDR pWaveHeader=(LPWAVEHDR)dwParam1;

 switch(uMsg)
 {

  case   MM_WOM_OPEN:

  /* FillBuffer (pBuffer1, iFreq) ;
   waveOutWrite (hWaveOut, pWaveHdr1, sizeof (WAVEHDR)) ;
   FillBuffer (pBuffer2, iFreq) ;
   waveOutWrite (hWaveOut, pWaveHdr2, sizeof (WAVEHDR)) ;*/
   return TRUE ;

  case   MM_WOM_DONE:

   iFreq +=20;
   waveOutUnprepareHeader(hWaveOut,pWaveHeader,sizeof(WAVEHDR));
   FillBuffer ((unsigned char *)pWaveHeader->lpData, iFreq) ;
   waveOutPrepareHeader(hWaveOut,pWaveHeader,sizeof(WAVEHDR));
   waveOutWrite (hWaveOut, pWaveHeader, sizeof (WAVEHDR)) ;
   return TRUE ;

 

  case   MM_WOM_CLOSE:

   waveOutUnprepareHeader (hWaveOut, pWaveHdr1, sizeof (WAVEHDR)) ;

   waveOutUnprepareHeader (hWaveOut, pWaveHdr2, sizeof (WAVEHDR)) ;

   free (pWaveHdr1) ;
   free (pWaveHdr2) ;
   free (pBuffer1) ;
   free (pBuffer2) ;
   hWaveOut = NULL ;

   return TRUE ;

  default:
   return TRUE ;
 }
}

void main(int argc, char* argv[])
{

    pWaveHdr1     = (PWAVEHDR)malloc (sizeof (WAVEHDR)) ;
    pWaveHdr2     = (PWAVEHDR)malloc (sizeof (WAVEHDR)) ;
    pBuffer1      = (PBYTE)malloc (OUT_BUFFER_SIZE) ;
    pBuffer2      = (PBYTE)malloc (OUT_BUFFER_SIZE) ;

if (!pWaveHdr1 || !pWaveHdr2 || !pBuffer1 || !pBuffer2)
{

    if (!pWaveHdr1) free (pWaveHdr1) ;
    if (!pWaveHdr2) free (pWaveHdr2) ;
    if (!pBuffer1)  free (pBuffer1) ;
    if (!pBuffer2)  free (pBuffer2) ;

}

waveformat.wFormatTag                = WAVE_FORMAT_PCM ;
waveformat.nChannels                 = 1 ;
waveformat.nSamplesPerSec            = SAMPLE_RATE ;
waveformat.nAvgBytesPerSec           = SAMPLE_RATE ;
waveformat.nBlockAlign               = 1 ;
waveformat.wBitsPerSample            = 8 ;
waveformat.cbSize                    = 0 ;

 

if (waveOutOpen (&hWaveOut, WAVE_MAPPER, &waveformat,
(DWORD)waveOutProc, 0, CALLBACK_FUNCTION)!= MMSYSERR_NOERROR)
{
    free (pWaveHdr1) ;
    free (pWaveHdr2) ;
    free (pBuffer1) ;
    free (pBuffer2) ;

}

// Set up headers and prepare them

pWaveHdr1->lpData                                               = (char *)pBuffer1 ;
pWaveHdr1->dwBufferLength                                       = OUT_BUFFER_SIZE ;
pWaveHdr1->dwBytesRecorded                                      = 0 ;
pWaveHdr1->dwUser                                               = 0 ;
pWaveHdr1->dwFlags                                              = 0 ;
pWaveHdr1->dwLoops                                              = 1 ;
pWaveHdr1->lpNext                                               = pWaveHdr2;
pWaveHdr1->reserved                                             = 0 ;

 

waveOutPrepareHeader (hWaveOut, pWaveHdr1, sizeof (WAVEHDR)) ;

pWaveHdr2->lpData                                               = (char *)pBuffer2 ;
pWaveHdr2->dwBufferLength                                       = OUT_BUFFER_SIZE ;
pWaveHdr2->dwBytesRecorded                                      = 0 ;
pWaveHdr2->dwUser                                               = 0 ;
pWaveHdr2->dwFlags                                              = 0 ;
pWaveHdr2->dwLoops                                              = 1 ;
pWaveHdr2->lpNext                                              = pWaveHdr1;
pWaveHdr2->reserved                                             = 0 ;

waveOutPrepareHeader (hWaveOut, pWaveHdr2, sizeof (WAVEHDR)) ;

FillBuffer (pBuffer1, 2000) ;
waveOutWrite (hWaveOut, pWaveHdr1, sizeof (WAVEHDR)) ;
FillBuffer (pBuffer2, 2000) ;
waveOutWrite (hWaveOut, pWaveHdr2, sizeof (WAVEHDR)) ;

getchar();
waveOutClose(hWaveOut);
}