IDirectSoundNotify8 is an interface to get notified on playback on capture audio buffer reaching certain position in the buffer. It is a must thing when implementing ring buffers with new data continuously added to the buffer for seamless playback (continuously copied from in case of capture).

This project is a minimalistic C++ sample code to illustrate the API. To initialize the DirectSound subsystem it is required to provide a window handle, which is created using ATL’s CWindowImpl (CMessageOnlyWindowImpl).

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ATLENSURE_SUCCEEDED(DirectSoundCreate8(NULL, &pDirectSound8, NULL));
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ATLENSURE_SUCCEEDED(pDirectSound8->SetCooperativeLevel(Window, DSSCL_PRIORITY));
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ATLENSURE_SUCCEEDED(pDirectSound8->CreateSoundBuffer(&BufferDescriptor, &pDirectSoundBuffer, NULL));
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CComQIPtr<IDirectSoundNotify8, &IID_IDirectSoundNotify8> pDirectSoundNotify8 = pDirectSoundBuffer;
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ATLENSURE_SUCCEEDED(pDirectSoundNotify8->SetNotificationPositions(g_nPositionCount, pPositionNotify));
ATLENSURE_SUCCEEDED(pDirectSoundBuffer->Play(0, 0, DSBPLAY_LOOPING));

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