我需要编写一个可以在 IGraphBuilder 或任何其他 Windows API 的帮助下直接播放 .ogg Vorbis 文件的程序(在 C++/win32 API 中)?
我尝试使用 IGraphBuilder 但这对我不起作用。示例代码:
IMediaControl *pControl = NULL;
IGraphBuilder *pGraph= NULL;
IMediaEventEx *pEvent= NULL;
IMediaPosition *pMediaPosition= NULL;
hr = ::CoCreateInstance(CLSID_FilterGraph, NULL, CLSCTX_INPROC_SERVER,
IID_IGraphBuilder, (void **)&pGraph);
if (FAILED(hr)) {
return false;
}
hr = pGraph->AddFilter(pFilter, L"Out");
hr = pGraph->QueryInterface(IID_IMediaControl, (void **)&pControl);
hr = pGraph->QueryInterface(IID_IMediaEvent, (void **)&pEvent);
hr = pGraph->QueryInterface(IID_IMediaPosition, (void**)&pMediaPosition);
// Build the graph.
hr = pGraph->RenderFile(mFilePath.c_str()/*"C:\\sample.ogg file"*/, NULL);
/* here hr = 0x80040265 so SUCCEEDED(hr) didnt allow it to enter in if condition*/
if (SUCCEEDED(hr)) {
// Run the graph.
hr = pControl->Run();
if (SUCCEEDED(hr)) {
// Wait for completion.
long evCode;
pEvent->WaitForCompletion(INFINITE, &evCode);
}
}
// Clean up in reverse order.
SAFE_RELEASE(pEvent);
SAFE_RELEASE(pControl);
SAFE_RELEASE(pGraph);
pGraph = NULL;
::CoUninitialize();
注意:上面的语句hr = pGraph->RenderFile()
返回 hr = 0x80040265 并且条件if (SUCCEEDED(hr))
不允许播放它。
如果我不使用此条件,则pControl->Run()
返回 ID_OK 执行。但是没有用扬声器播放。请提出解决方案/方法。