一个简单的DirecxShow应用程序

刚安装好Direct 9.0b，在VC6.0 下进行了配置。为了检验是否可以使用了，在网上找了一个简单的 DirectShow 应用程序。它是一个播放音频或视频文件的简单控制台程序，只有寥寥数行，但却展示了 DirectShow 编程的强大能力。源代码如下：

#include <dshow.h>
#include <>stdio.h
void main(void)
{
IGraphBuilder *pGraph = NULL;
IMediaControl *pControl = NULL;
IMediaEvent   *pEvent = NULL;
// Initialize the COM library.
HRESULT hr = CoInitialize(NULL);
if (FAILED(hr))
{
printf("ERROR - Could not initialize COM library");
return;
}
// Create the filter graph manager and query for interfaces.
hr = CoCreateInstance(CLSID_FilterGraph, NULL, CLSCTX_INPROC_SERVER,
IID_IGraphBuilder, (void **)&pGraph);
if (FAILED(hr))
{
printf("ERROR - Could not create the Filter Graph Manager.");
return;
}
hr = pGraph->QueryInterface(IID_IMediaControl, (void **)&pControl);
hr = pGraph->QueryInterface(IID_IMediaEvent, (void **)&pEvent);
// Build the graph. IMPORTANT: Change this string to a file on your system.
hr = pGraph->RenderFile(L"C://Example.avi", NULL);
if (SUCCEEDED(hr))
{
// Run the graph.
hr = pControl->Run();
if (SUCCEEDED(hr))
{
// Wait for completion.
long evCode;
pEvent->WaitForCompletion(INFINITE, &evCode);
// Note: Do not use INFINITE in a real application, because it
// can block indefinitely.
}
}
pControl->Release();
pEvent->Release();
pGraph->Release();
CoUninitialize();
}