MFC+DirectShow摄像头简单视频浏览

1 安装摄像头驱动

2 引用DirectShow库，包含DirectShow头文件

#pragma comment(lib,"Strmiids.lib")

#pragma comment(lib,"quartz.lib")

#include "dshow.h"

3 初始化com环境

::CoInitialize(NULL);

4 定义一个过滤器引脚查询函数,并实现之

定义

IPin *findpin(IBaseFilter *pFilter,PIN_DIRECTION dir);

实现，假定工程为MFC Dialog Based类型，主对话框类为VDlg

IPin *VDlg::findpin(IBaseFilter *pFilter,PIN_DIRECTION dir)

{

IEnumPins *pEnumPins=NULL;

IPin *pRetPin=NULL;

PIN_DIRECTION pDir;

pFilter->EnumPins(&pEnumPins);

while(pEnumPins->Next(1,&pRetPin,NULL)==S_OK)

{

pRectPin->QueryDirection(&pDir);

if(pDir==dir)

{

return pRetPin;

}

}

return 0;

}

5 预览实现

void VDlg::vPreview()

{

ICaptureGraphBuilder *pBuilder=NULL;

::CoCreateInstance(CLSID_CaptureGraphBuilder2,NULL,CLSCTX_INPROC_SERVER,IID_ICaptureGraphBuilder2,(void **)&pBuilder);

::CoCreateInstance(CLSID_FilterGraph,NULL,CLSCTX_INPROC_SERVER,IID_IGraphBuilder,(void **)&pGraph);

pBuilder->SetFiltergraph(pGraph);

ICreateDevEnum *pDevEnum=NULL;

IEnumMoniker *pClsEnum=NULL;

::CoCreateInstance(CLSID_SystemDeviceEnum,NULL,CLSCTX_INPROC,IID_ICreateDevEnum,(void **)&pDevEnum);

pDevEnum->CreateClassEnumerator(CLSID_VideoInputDeviceCategory,&pClsEnum,0);

if(pClsEnum->Next(1,&pMoniker,NULL)==S_OK)

{

pMoniker->BindToObject(0,0,IID_IBaseFilter,(void **)&pSrc);

pMoniker->Release();

}

pClsEnum->Release();

pGraph->AddFilter(pSrc,L"AVI");

::CoCreateInstance(CLSID_VideoRenderer,NULL,CLSCTX_ALL,IID_IBaseFilter,(void **)&pPreview);

if(pPreview)

{

pGraph->AddFilter(pPreview,L"PREVIEW");

IPin *pPinOut,*pPinIn;

pPinOut=findpin(pSrc,PINDIR_OUTPUT);

pPinIn=findpin(pPreview,PINDIR_INPUT);

pGraph->ConnectDirect(pPinOut,pPinIn,0);

IVideoWindow *pWnd=NULL;

pPreview->QueryInterface(IID_IVideowindow,(void **)&pWnd);

if(pWnd)

{

long ws;

pWnd->put_Owner((long)m_hWnd);

pWnd->get_WindowStyle(&ws);

ws=ws &~ WS_CAPTION;

ws=ws &~WS_DLGFRAME;

ws=ws & WS_CHILD;

pWnd->put_WindowStyle(ws);

CRect rc;

this->GetClientRect(rc);

pWnd->put_Lef(5);

pWnd->put_Top(5);

pWnd->put_Width(rc.Width()-5);

pWnd->put_Height(rc.Height()-5);

}

pMediaCtrl->Run();

}

}