Directshow_結構調試_GraphEdit

Directshow_結構調試_GraphEdit

介紹

編寫Directshow時，我們可以通過 GraphEdit.exe 展示當前應用的Directshow的結構

1.添加通信代碼

HRESULT AddToRot(IUnknown *pUnkGraph, DWORD *pdwRegister) 
{
    IMoniker * pMoniker = NULL;
    IRunningObjectTable *pROT = NULL;

    if (FAILED(GetRunningObjectTable(0, &pROT))) 
    {
        return E_FAIL;
    }
    
    const size_t STRING_LENGTH = 256;

    WCHAR wsz[STRING_LENGTH];
 
   StringCchPrintfW(
        wsz, STRING_LENGTH, 
        L"FilterGraph %08x pid %08x", 
        (DWORD_PTR)pUnkGraph, 
        GetCurrentProcessId()
        );
    
    HRESULT hr = CreateItemMoniker(L"!", wsz, &pMoniker);
    if (SUCCEEDED(hr)) 
    {
        hr = pROT->Register(ROTFLAGS_REGISTRATIONKEEPSALIVE, pUnkGraph,
            pMoniker, pdwRegister);
        pMoniker->Release();
    }
    pROT->Release();
    
    return hr;
}

2. 刪除通信代碼

void RemoveFromRot(DWORD pdwRegister)
{
    IRunningObjectTable *pROT;
    if (SUCCEEDED(GetRunningObjectTable(0, &pROT))) {
        pROT->Revoke(pdwRegister);
        pROT->Release();
    }
}

3.實際使用

#include <dshow.h>
#pragma comment (lib,"Strmiids.lib")
#pragma comment (lib,"Quartz.lib")

void RemoveFromRot(DWORD pdwRegister)
{
	IRunningObjectTable *pROT;
	if (SUCCEEDED(GetRunningObjectTable(0, &pROT))) {
		pROT->Revoke(pdwRegister);
		pROT->Release();
	}
}
// CPlayFileDlg 消息處理程序
HRESULT AddToRot(IUnknown *pUnkGraph, DWORD *pdwRegister)
{
	IMoniker * pMoniker = NULL;
	IRunningObjectTable *pROT = NULL;

	if (FAILED(GetRunningObjectTable(0, &pROT)))
	{
		return E_FAIL;
	}

	const size_t STRING_LENGTH = 256;

	WCHAR wsz[STRING_LENGTH];

	StringCchPrintfW(
		wsz, STRING_LENGTH,
		L"FilterGraph %08x pid %08x",
		(DWORD_PTR)pUnkGraph,
		GetCurrentProcessId()
	);

	HRESULT hr = CreateItemMoniker(L"!", wsz, &pMoniker);
	if (SUCCEEDED(hr))
	{
		hr = pROT->Register(ROTFLAGS_REGISTRATIONKEEPSALIVE, pUnkGraph,
			pMoniker, pdwRegister);
		pMoniker->Release();
	}
	pROT->Release();

	return hr;
}

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;
    }
    DWORD dwRegister;
#ifdef _DEBUG
	hr = AddToRot(pGraph, &dwRegister);
#endif
    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"D:\\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.
        }
    }
#ifdef _DEBUG
	RemoveFromRot(dwRegister);
#endif
    pControl->Release();
    pEvent->Release();
    pGraph->Release();
    CoUninitialize();
}

4.建立連接

運行上面的程序
右鍵以管理員運行 GraphEdit.exe，選擇file->Connect to Remote Graph…

點擊OK