How do I, say, play a sound with a given amplitude and a given frequency makeup (say, consisting of frequencies 2 kHz and 3 kHz) natively on Windows (32-bit and 64-bit, up to Windows 7)?
(By natively I mean without using an external library.)
I believe this needs the waveOutWrite method but I have no idea how it works.
I got something working...
#define _USE_MATH_DEFINES 1
#include <math.h>
#include <stdio.h>
#include <tchar.h>
#include <windows.h>
#include <mmreg.h>
#include <complex>
#pragma comment(lib, "Winmm.lib")
MMRESULT play(float nSeconds,
float signal(float timeInSeconds, unsigned short channel, void *context),
void *context = NULL, unsigned long samplesPerSecond = 48000)
{
UINT timePeriod = 1;
MMRESULT mmresult = MMSYSERR_NOERROR;
WAVEFORMATEX waveFormat = {0};
waveFormat.cbSize = 0;
waveFormat.wFormatTag = WAVE_FORMAT_IEEE_FLOAT;
waveFormat.nChannels = 2;
waveFormat.nSamplesPerSec = samplesPerSecond;
const size_t nBuffer =
(size_t)(nSeconds * waveFormat.nChannels * waveFormat.nSamplesPerSec);
float *buffer;
waveFormat.wBitsPerSample = CHAR_BIT * sizeof(buffer[0]);
waveFormat.nBlockAlign =
waveFormat.nChannels * waveFormat.wBitsPerSample / CHAR_BIT;
waveFormat.nAvgBytesPerSec =
waveFormat.nSamplesPerSec * waveFormat.nBlockAlign;
buffer = (float *)calloc(nBuffer, sizeof(*buffer));
__try
{
for (size_t i = 0; i < nBuffer; i += waveFormat.nChannels)
for (unsigned short j = 0; j < waveFormat.nChannels; j++)
buffer[i+j] = signal((i+j) * nSeconds / nBuffer, j, context);
HWAVEOUT hWavOut = NULL;
mmresult = waveOutOpen(&hWavOut, WAVE_MAPPER,
&waveFormat, NULL, NULL, CALLBACK_NULL);
if (mmresult == MMSYSERR_NOERROR)
{
__try
{
timeBeginPeriod(timePeriod);
__try
{
WAVEHDR hdr = {0};
hdr.dwBufferLength =
(ULONG)(nBuffer * sizeof(buffer[0]));
hdr.lpData = (LPSTR)&buffer[0];
mmresult = waveOutPrepareHeader(hWavOut,
&hdr, sizeof(hdr));
if (mmresult == MMSYSERR_NOERROR)
{
__try
{
ULONG start = GetTickCount();
mmresult =
waveOutWrite(hWavOut, &hdr, sizeof(hdr));
Sleep((ULONG)(1000 * nSeconds
- (GetTickCount() - start)));
}
__finally
{ waveOutUnprepareHeader(hWavOut, &hdr, sizeof(hdr)); }
}
}
__finally { timeEndPeriod(timePeriod); }
}
__finally { waveOutClose(hWavOut); }
}
}
__finally { free(buffer); }
return mmresult;
}
// Triangle wave generator
float triangle(float timeInSeconds, unsigned short channel, void *context)
{
const float frequency = *(const float *)context;
const float angle = (float)(frequency * 2 * M_PI * timeInSeconds);
switch (channel)
{
case 0: return (float)asin(sin(angle + 0 * M_PI / 2));
default: return (float)asin(sin(angle + 1 * M_PI / 2));
}
}
// Pure tone generator
float pure(float timeInSeconds, unsigned short channel, void *context)
{
const float frequency = *(const float *)context;
const float angle = (float)(frequency * 2 * M_PI * timeInSeconds);
switch (channel)
{
case 0: return (float)sin(angle + 0 * M_PI / 2);
default: return (float)sin(angle + 1 * M_PI / 2);
}
}
int _tmain(int argc, _TCHAR* argv[])
{
float frequency = 2 * 261.626F;
play(1, pure, &frequency);
return 0;
}
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With