public DirectSound(
Form form,
int sampleRate,
int bufferCount)
{
if ((sampleRate % 50) != 0)
{
throw new ArgumentOutOfRangeException("sampleRate", "Sample rate must be a multiple of 50!");
}
_sampleRate = sampleRate;
var bufferSize = sampleRate / 50;
for (int i = 0; i < bufferCount; i++)
{
_fillQueue.Enqueue(new uint[bufferSize]);
}
_bufferSize = bufferSize;
_bufferCount = bufferCount;
_zeroValue = 0;
var hWnd = form != null ? form.Handle : IntPtr.Zero;
_device = new DirectSound8();
_device.SetCooperativeLevel(hWnd, DSSCL.PRIORITY);
// we always use 16 bit stereo (uint per sample)
const short channels = 2;
const short bitsPerSample = 16;
const int sampleSize = 4; // channels * (bitsPerSample / 8);
var wf = new WaveFormat(_sampleRate, bitsPerSample, channels);
// Create a buffer
var bufferDesc = new DSBUFFERDESC();
bufferDesc.dwBufferBytes = _bufferSize * sampleSize * _bufferCount;
bufferDesc.dwFlags =
DSBCAPS_FLAGS.CTRLVOLUME |
DSBCAPS_FLAGS.CTRLPOSITIONNOTIFY |
DSBCAPS_FLAGS.GLOBALFOCUS |
DSBCAPS_FLAGS.GETCURRENTPOSITION2;
bufferDesc.Format = wf;
_soundBuffer = new SecondarySoundBuffer(_device, bufferDesc);
var posNotify = new DSBPOSITIONNOTIFY[_bufferCount];
for (int i = 0; i < posNotify.Length; i++)
{
posNotify[i] = new DSBPOSITIONNOTIFY();
posNotify[i].dwOffset = i * _bufferSize * sampleSize;
posNotify[i].WaitHandle = _fillEvent;
}
_soundBuffer.SetNotificationPositions(posNotify);
_wavePlayThread = new Thread(WavePlayThreadProc);
_wavePlayThread.IsBackground = true;
_wavePlayThread.Name = "WavePlay";
_wavePlayThread.Priority = ThreadPriority.Highest;
_wavePlayThread.Start();
}
private bool CreateBufferNotifications()
{
uint error = DSERR.DS_OK;
// 获取IDirectSoundNotify8接口
Guid iid_dsNotify8 = new Guid(InterfaceID.IID_IDirectSoundNotify8);
IntPtr pdsNotify8;
IDirectSoundNotify8 dsNotify8;
Marshal.QueryInterface(this.pdscb8, ref iid_dsNotify8, out pdsNotify8);
dsNotify8 = Marshal.GetObjectForIUnknown(pdsNotify8) as IDirectSoundNotify8;
try
{
WAVEFORMATEX wfx;
int pdwSizeWritten;
if ((error = this.dscb8.GetFormat(out wfx, Marshal.SizeOf(typeof(WAVEFORMATEX)), out pdwSizeWritten)) != DSERR.DS_OK)
{
logger.ErrorFormat("GetFormat失败, DSERROR = {0}", error);
return(false);
}
DSBPOSITIONNOTIFY[] rgdsbpn = new DSBPOSITIONNOTIFY[this.NotifyEvents];
this.notifyHandle_close = new IntPtr[this.NotifyEvents];
for (int i = 0; i < this.NotifyEvents; i++)
{
this.notifyHandle_close[i] = Win32API.CreateEvent(IntPtr.Zero, true, false, null);
}
rgdsbpn[0].dwOffset = (uint)(wfx.nAvgBytesPerSec - 1);
rgdsbpn[0].hEventNotify = this.notifyHandle_close[0];
rgdsbpn[1].dwOffset = Win32API.DSBPN_OFFSETSTOP;
rgdsbpn[1].hEventNotify = this.notifyHandle_close[1];
if ((error = dsNotify8.SetNotificationPositions(this.NotifyEvents, Marshal.UnsafeAddrOfPinnedArrayElement(rgdsbpn, 0))) != DSERR.DS_OK)
{
logger.ErrorFormat("SetNotificationPositions失败, DSERROR = {0}", error);
return(false);
}
}
finally
{
Marshal.Release(pdsNotify8);
}
return(true);
}
