在图像处理时经常会用到从摄像头读取图像。OPENCV有提供的方法来实现，非常简单，不用多说。而使用VC++则没有那么容易，下面介绍使用CImage和DirectShow读取摄像头图像，并显示的对话框中。
我用的开发工具是VS2010。
源代码下载，使用VS2010编译通过。
http://download.csdn.net/detail/sdlypyzq/4087013
一、创建一个MFC对话框程序，工程起名为CameraVCTest。
二、删除无用的控件和按钮。添加一个图片控件，ID为IDC_PICTURE，并为其添加CStatic
类型变量m_picture。添加四个按钮，名称分别为预览，拍照，保存，关闭。ID分别为IDC_VIEW,IDC_TAKEPHOTO,IDC_SAVE,IDC_CLOSE。分别为其添加变量m_view,m_takePhoto,m_save,m_close。双击四个按钮，生成四个响应函数。
三、将DirectShow文件夹和CameraDS类的头文件和源文件拷贝到项目源文件夹下。并在项目属性VC++ Directories添加include Directories，“.\DirectShow”。在Solution Exlporer添加上CameraDS类的头文件和源文件。
四、在CCameraVCTestDlg 类的头文件中，添加
#include "CameraDS.h" #include using namespace std;
添加公共变量和方法
vector cameralist; CImage *m_pImage; void ShowPicture(CImage *img,CStatic *pic); voidSaveCard(CImage *img); int m_cam_count; bool isBreak; CString m_savePath; CString savePath; intm_saveIndex; int m_fileCount;
在源文件的初始化函数里添加：
m_cam_count = CCameraDS::CameraCount(); cameralist.resize(m_cam_count); if(! cameralist[m_cam_count-1].OpenCamera(m_cam_count-1, false, 640,480)) { return FALSE; } this->isBreak = false; this->isSave = false; this->m_view.EnableWindow(TRUE); this->m_takePhoto.EnableWindow(FALSE); this->m_save.EnableWindow(FALSE);
添加如下函数
void DoEvents1() { MSG msg; if (::PeekMessage(&msg,NULL,0,0,PM_REMOVE)) { ::TranslateMessage(&msg); ::DispatchMessage(&msg); } } void CCameraVCTestDlg::OnBnClickedView() {// TODO: Add your control notification handler code here this->isBreak = false; this->m_view.EnableWindow(FALSE); this->m_takePhoto.EnableWindow(TRUE); this->m_save.EnableWindow(FALSE); if(m_cam_count==0) { return ; }//CImage imgShow;//imgShow.Create(this->MAX_WIDTH,this->MAX_HEIGHT,24); while(1) { DoEvents1(); if(isBreak) {break; } this->m_pImage = cameralist[m_cam_count-1].QueryFrame2(); this->ShowPicture(m_pImage,&this->m_picture); //if(m_fileCount == 100) //{ // this->isBreak = true; //this->m_bnInit.EnableWindow(TRUE); // this->m_bnTake.EnableWindow(FALSE); // this->m_bnSave.EnableWindow(TRUE); // break; //} if(isSave) { if(this->m_fileCount<<span style="color: #800080;">100) { //this->m_ctrlProg.SetPos(m_fileCount); CString path; path.Format(L"%s\\%d.jpg",savePath,m_fileCount+m_saveIndex); this->m_pImage->Save(path); m_fileCount++; } else { isSave = false; this->m_view.EnableWindow(FALSE); this->m_takePhoto.EnableWindow(TRUE); //this->m_save.EnableWindow(TRUE); } } Sleep(150); } }
添加视频帧显示函数
void CCameraVCTestDlg::ShowPicture(CImage *img,CStatic *pic) { if(img==NULL) { return ; } intwidth = img->GetWidth(); int height = img->GetHeight(); CRect picRect; this->m_picture.GetClientRect(&picRect); CRect rt(picRect); CDC* dc = this->m_picture.GetDC(); CBrush*pBrush = CBrush::FromHandle((HBRUSH)GetStockObject(WHITE_BRUSH)); //dc->FillRect(rt, pBrush);if(picRect.Height()*width > height*picRect.Width()) { CPoint p1(0,(picRect.Height()-(picRect.Width()*height/width))/2); CPoint p2(picRect.Width(),(picRect.Height() - p1.y)); rt.SetRect(p1,p2); } else { CPoint p1((picRect.Width()-(picRect.Height()*width/height))/2,0); CPoint p2(picRect.Width()-p1.x,picRect.Height()); rt.SetRect(p1,p2); } // } // this->ShowMouseCursor(CursorTag); ::SetStretchBltMode(dc->m_hDC,HALFTONE); img->Draw(dc->m_hDC, rt); }
添加关闭程序
void CCameraVCTestDlg::OnBnClickedClose() { this->isBreak = true; this->OnClose(); }
好了，现在对话框上，点击预览按钮，就可以打开摄像头了，若还需要什么功能自己添加吧，如有问题，可以一起交流。欢迎不吝赐教。
Camera.h
1 #ifndef POINTER_642 3 4 #if !defined(_MAC) && (defined(_M_MRX000) || defined(_M_AMD64) || defined(_M_IA64)) && (_MSC_VER >= 1100) && !(defined(MIDL_PASS) || defined(RC_INVOKED))5 #define POINTER_64 __ptr646 typedef unsigned __int64 POINTER_64_INT;7 #if defined(_WIN64)8 #define POINTER_32 __ptr329 #else10 #define POINTER_3211 #endif12 #else13 #if defined(_MAC) && defined(_MAC_INT_64)14 #define POINTER_64 __ptr6415 typedef unsigned __int64 POINTER_64_INT;16 #else17 #if (_MSC_VER >= 1300) && !(defined(MIDL_PASS) || defined(RC_INVOKED))18 #define POINTER_64 __ptr6419 #else20 #define POINTER_6421 #endif22 typedef unsigned long POINTER_64_INT;23 #endif24 #define POINTER_3225 #endif26 27 #endif28 29 30 31 32 33 #ifndef CCAMERA_H34 #define CCAMERA_H35 36 #define WIN32_LEAN_AND_MEAN37 38 #include <</span>atlbase.h>39 #include "qedit.h"40 #include "dshow.h"41 #include <</span>windows.h>42 //#include "cv.h"43 44 //#include 45 46 #define MYFREEMEDIATYPE(mt) {if ((mt).cbFormat != 0) \47 {CoTaskMemFree((PVOID)(mt).pbFormat); \48 (mt).cbFormat =0; \49 (mt).pbFormat = NULL; \50 } \51 if ((mt).pUnk != NULL) \52 { \53 (mt).pUnk->Release(); \54 (mt).pUnk = NULL; \55 }} 56 57 58 class CCameraDS 59 {60 private:61 // IplImage * m_pFrame;62 CImage m_image;63 bool m_bConnected;64 int m_nWidth;65 int m_nHeight;66 bool m_bLock;67 bool m_bChanged;68 long m_nBufferSize;69 70 CComPtr<</span>IGraphBuilder> m_pGraph;71 CComPtr<</span>IBaseFilter> m_pDeviceFilter;72 CComPtr<</span>IMediaControl> m_pMediaControl;73 CComPtr<</span>IBaseFilter> m_pSampleGrabberFilter;74 CComPtr<</span>ISampleGrabber> m_pSampleGrabber;75 CComPtr<</span>IPin> m_pGrabberInput;76 CComPtr<</span>IPin> m_pGrabberOutput;77 CComPtr<</span>IPin> m_pCameraOutput;78 CComPtr<</span>IMediaEvent> m_pMediaEvent;79 CComPtr<</span>IBaseFilter> m_pNullFilter;80 CComPtr<</span>IPin> m_pNullInputPin;81 82 private:83 bool BindFilter(int nCamIDX, IBaseFilter **pFilter);84 void SetCrossBar();85 86 public:87 CCameraDS();88 virtual~CCameraDS();89 90 //打开摄像头，nCamID指定打开哪个摄像头，取值可以为0,1,2,...91 //bDisplayProperties指示是否自动弹出摄像头属性页92 //nWidth和nHeight设置的摄像头的宽和高，如果摄像头不支持所设定的宽度和高度，则返回false93 bool CCameraDS::OpenCamera(int nCamID, bool bDisplayProperties=true, int nWidth =320, intnHeight =240);94 95 //关闭摄像头，析构函数会自动调用这个函数96 void CloseCamera();97 98 //返回摄像头的数目99 //可以不用创建CCameraDS实例，采用int c=CCameraDS::CameraCount();得到结果。100 staticint CameraCount(); 101 102 //根据摄像头的编号返回摄像头的名字103 //nCamID: 摄像头编号104 //sName: 用于存放摄像头名字的数组105 //nBufferSize: sName的大小106 //可以不用创建CCameraDS实例，采用CCameraDS::CameraName();得到结果。107 staticint CCameraDS::CameraName(int nCamID, char* sName, int nBufferSize);108 109 //返回图像宽度110 int GetWidth(){return m_nWidth;} 111 112 //返回图像高度113 int GetHeight(){return m_nHeight;}114 115 //抓取一帧，返回的IplImage不可手动释放！116 //返回图像数据的为RGB模式的Top-down(第一个字节为左上角像素)，即IplImage::origin=0(IPL_ORIGIN_TL)117 // IplImage * QueryFrame();118 CImage* QueryFrame2(); 119 };120 121 #endifcamera.cpp
#include "stdafx.h"#include "CameraDS.h"#pragma comment(lib,"Strmiids.lib") //////////////////////////////////////////////////////////////////////// Construction/Destruction//////////////////////////////////////////////////////////////////////CCameraDS::CCameraDS(){m_bConnected =false;m_nWidth =0;m_nHeight =0;m_bLock =false;m_bChanged =false;// m_pFrame = NULL;m_nBufferSize =0;m_pNullFilter = NULL;m_pMediaEvent = NULL;m_pSampleGrabberFilter = NULL;m_pGraph = NULL;CoInitialize(NULL);}CCameraDS::~CCameraDS(){CloseCamera();CoUninitialize();}void CCameraDS::CloseCamera(){if(m_bConnected)m_pMediaControl->Stop();m_pGraph = NULL;m_pDeviceFilter = NULL;m_pMediaControl = NULL;m_pSampleGrabberFilter = NULL;m_pSampleGrabber = NULL;m_pGrabberInput = NULL;m_pGrabberOutput = NULL;m_pCameraOutput = NULL;m_pMediaEvent = NULL;m_pNullFilter = NULL;m_pNullInputPin = NULL;//if (m_pFrame)// cvReleaseImage(&m_pFrame);if(!this->m_image.IsNull()){this->m_image.Destroy();}m_bConnected =false;m_nWidth =0;m_nHeight =0;m_bLock =false;m_bChanged =false;m_nBufferSize =0;}bool CCameraDS::OpenCamera(int nCamID, bool bDisplayProperties, int nWidth, int nHeight){HRESULT hr = S_OK;CoInitialize(NULL);// Create the Filter Graph Manager.hr = CoCreateInstance(CLSID_FilterGraph, NULL, CLSCTX_INPROC,IID_IGraphBuilder, (void**)&m_pGraph);hr = CoCreateInstance(CLSID_SampleGrabber, NULL, CLSCTX_INPROC_SERVER, IID_IBaseFilter, (LPVOID *)&m_pSampleGrabberFilter);hr = m_pGraph->QueryInterface(IID_IMediaControl, (void**) &m_pMediaControl);hr = m_pGraph->QueryInterface(IID_IMediaEvent, (void**) &m_pMediaEvent);hr = CoCreateInstance(CLSID_NullRenderer, NULL, CLSCTX_INPROC_SERVER,IID_IBaseFilter, (LPVOID*) &m_pNullFilter);hr = m_pGraph->AddFilter(m_pNullFilter, L"NullRenderer");hr = m_pSampleGrabberFilter->QueryInterface(IID_ISampleGrabber, (void**)&m_pSampleGrabber);AM_MEDIA_TYPE mt;ZeroMemory(&mt, sizeof(AM_MEDIA_TYPE));mt.majortype = MEDIATYPE_Video;mt.subtype = MEDIASUBTYPE_RGB24;mt.formattype = FORMAT_VideoInfo; hr = m_pSampleGrabber->SetMediaType(&mt);MYFREEMEDIATYPE(mt);m_pGraph->AddFilter(m_pSampleGrabberFilter, L"Grabber");// Bind Device Filter. We know the device because the id was passed inBindFilter(nCamID, &m_pDeviceFilter);m_pGraph->AddFilter(m_pDeviceFilter, NULL);CComPtr<</span>IEnumPins> pEnum;m_pDeviceFilter->EnumPins(&pEnum);hr = pEnum->Reset();hr = pEnum->Next(1, &m_pCameraOutput, NULL); pEnum = NULL; m_pSampleGrabberFilter->EnumPins(&pEnum);pEnum->Reset();hr = pEnum->Next(1, &m_pGrabberInput, NULL); pEnum = NULL;m_pSampleGrabberFilter->EnumPins(&pEnum);pEnum->Reset();pEnum->Skip(1);hr = pEnum->Next(1, &m_pGrabberOutput, NULL); pEnum = NULL;m_pNullFilter->EnumPins(&pEnum);pEnum->Reset();hr = pEnum->Next(1, &m_pNullInputPin, NULL);//SetCrossBar();if (bDisplayProperties) {CComPtr<</span>ISpecifyPropertyPages> pPages;HRESULT hr = m_pCameraOutput->QueryInterface(IID_ISpecifyPropertyPages, (void**)&pPages);if (SUCCEEDED(hr)){PIN_INFO PinInfo;m_pCameraOutput->QueryPinInfo(&PinInfo);CAUUID caGUID;pPages->GetPages(&caGUID);OleCreatePropertyFrame(NULL, 0, 0,L"Property Sheet", 1,(IUnknown **)&(m_pCameraOutput.p),caGUID.cElems,caGUID.pElems,0, 0, NULL);CoTaskMemFree(caGUID.pElems);PinInfo.pFilter->Release();}pPages = NULL;}else {//////////////////////////////////////////////////////////////////////////////// 加入由 lWidth和lHeight设置的摄像头的宽和高 的功能，默认320*240// by flymanbox @2009-01-24//////////////////////////////////////////////////////////////////////////////int _Width = nWidth, _Height = nHeight;IAMStreamConfig* iconfig; iconfig = NULL;hr = m_pCameraOutput->QueryInterface(IID_IAMStreamConfig, (void**)&iconfig); AM_MEDIA_TYPE* pmt; if(iconfig->GetFormat(&pmt) !=S_OK) {//printf("GetFormat Failed ! \n");returnfalse; }VIDEOINFOHEADER* phead;if ( pmt->formattype == FORMAT_VideoInfo) { phead=( VIDEOINFOHEADER*)pmt->pbFormat; phead->bmiHeader.biWidth = _Width; phead->bmiHeader.biHeight = _Height; if(( hr=iconfig->SetFormat(pmt)) != S_OK ) {returnfalse;}} iconfig->Release(); iconfig=NULL; MYFREEMEDIATYPE(*pmt);}hr = m_pGraph->Connect(m_pCameraOutput, m_pGrabberInput);hr = m_pGraph->Connect(m_pGrabberOutput, m_pNullInputPin);if (FAILED(hr)){switch(hr){case VFW_S_NOPREVIEWPIN :break;case E_FAIL :break;case E_INVALIDARG :break;case E_POINTER :break;}}m_pSampleGrabber->SetBufferSamples(TRUE);m_pSampleGrabber->SetOneShot(TRUE);hr = m_pSampleGrabber->GetConnectedMediaType(&mt);if(FAILED(hr))returnfalse;VIDEOINFOHEADER *videoHeader;videoHeader = reinterpret_cast<</span>VIDEOINFOHEADER*>(mt.pbFormat);m_nWidth = videoHeader->bmiHeader.biWidth;m_nHeight = videoHeader->bmiHeader.biHeight;m_bConnected =true;pEnum = NULL;returntrue;}bool CCameraDS::BindFilter(int nCamID, IBaseFilter **pFilter){if (nCamID <</span>0)returnfalse;// enumerate all video capture devicesCComPtr<</span>ICreateDevEnum> pCreateDevEnum;HRESULT hr = CoCreateInstance(CLSID_SystemDeviceEnum, NULL, CLSCTX_INPROC_SERVER,IID_ICreateDevEnum, (void**)&pCreateDevEnum);if (hr != NOERROR){returnfalse;}CComPtr<</span>IEnumMoniker> pEm;hr = pCreateDevEnum->CreateClassEnumerator(CLSID_VideoInputDeviceCategory,&pEm, 0);if (hr != NOERROR) {returnfalse;}pEm->Reset();ULONG cFetched;IMoniker *pM;int index =0;while(hr = pEm->Next(1, &pM, &cFetched), hr==S_OK, index <= nCamID){IPropertyBag *pBag;hr = pM->BindToStorage(0, 0, IID_IPropertyBag, (void**)&pBag);if(SUCCEEDED(hr)) {VARIANT var;var.vt = VT_BSTR;hr = pBag->Read(L"FriendlyName", &var, NULL);if (hr == NOERROR) {if (index == nCamID){pM->BindToObject(0, 0, IID_IBaseFilter, (void**)pFilter);}SysFreeString(var.bstrVal);}pBag->Release();}pM->Release();index++;}pCreateDevEnum = NULL;returntrue;}//将输入crossbar变成PhysConn_Video_Compositevoid CCameraDS::SetCrossBar(){int i;IAMCrossbar *pXBar1 = NULL;ICaptureGraphBuilder2 *pBuilder = NULL;HRESULT hr = CoCreateInstance(CLSID_CaptureGraphBuilder2, NULL,CLSCTX_INPROC_SERVER, IID_ICaptureGraphBuilder2, (void**)&pBuilder);if (SUCCEEDED(hr)){hr = pBuilder->SetFiltergraph(m_pGraph);}hr = pBuilder->FindInterface(&LOOK_UPSTREAM_ONLY, NULL, m_pDeviceFilter,IID_IAMCrossbar, (void**)&pXBar1);if (SUCCEEDED(hr)) {long OutputPinCount;long InputPinCount;long PinIndexRelated;long PhysicalType;long inPort =0;long outPort =0;pXBar1->get_PinCounts(&OutputPinCount,&InputPinCount);for( i =0;i<</span>InputPinCount;i++){pXBar1->get_CrossbarPinInfo(TRUE,i,&PinIndexRelated,&PhysicalType);if(PhysConn_Video_Composite==PhysicalType) {inPort = i;break;}}for( i =0;i<</span>OutputPinCount;i++){pXBar1->get_CrossbarPinInfo(FALSE,i,&PinIndexRelated,&PhysicalType);if(PhysConn_Video_VideoDecoder==PhysicalType) {outPort = i;break;}}if(S_OK==pXBar1->CanRoute(outPort,inPort)){pXBar1->Route(outPort,inPort);}pXBar1->Release(); }pBuilder->Release();}//IplImage* CCameraDS::QueryFrame()//{//// long evCode;// long size = 0;//// m_pMediaControl->Run();// m_pMediaEvent->WaitForCompletion(INFINITE, &evCode);// // m_pSampleGrabber->GetCurrentBuffer(&size, NULL);//////if the buffer size changed// if (size != m_nBufferSize)// {// if (m_pFrame)// cvReleaseImage(&m_pFrame);//// m_nBufferSize = size;// m_pFrame = cvCreateImage(cvSize(m_nWidth, m_nHeight), IPL_DEPTH_8U, 3);// }// if (m_pFrame == NULL) return NULL;// m_pSampleGrabber->GetCurrentBuffer(&m_nBufferSize, (long*)m_pFrame->imageData);// cvFlip(m_pFrame);//// return m_pFrame;//}CImage* CCameraDS::QueryFrame2(){long evCode;long size =0;m_pMediaControl->Run();m_pMediaEvent->WaitForCompletion(INFINITE, &evCode);m_pSampleGrabber->GetCurrentBuffer(&size, NULL);//if the buffer size changedif (size != m_nBufferSize){//if (m_pImage != NULL )//|| !m_pImage->IsNull())//{// m_pImage->Destroy();//}// cvReleaseImage(&m_pFrame);m_nBufferSize = size;//m_pFrame = cvCreateImage(cvSize(m_nWidth, m_nHeight), IPL_DEPTH_8U, 3);m_image.Create(m_nWidth,m_nHeight,24);}//if (m_pFrame == NULL) return NULL;if(m_image.IsNull()){return0;}byte*q;byte*p =newbyte[m_nWidth*m_nHeight*3];//m_pSampleGrabber->GetCurrentBuffer(&m_nBufferSize, (long*)m_pFrame->imageData);m_pSampleGrabber->GetCurrentBuffer(&m_nBufferSize, (long*)p);// cvFlip(m_pFrame);//for(int y=0, z=m_nHeight-1; y<</span>m_nHeight,z>=0; y++,z--){q = (byte*)m_image.GetPixelAddress(0,z);memcpy(q,&p[m_nWidth*3*y],m_nWidth*3);}delete []p;return&m_image;}int CCameraDS::CameraCount(){int count =0;CoInitialize(NULL);// enumerate all video capture devicesCComPtr<</span>ICreateDevEnum> pCreateDevEnum;HRESULT hr = CoCreateInstance(CLSID_SystemDeviceEnum, NULL, CLSCTX_INPROC_SERVER,IID_ICreateDevEnum, (void**)&pCreateDevEnum);CComPtr<</span>IEnumMoniker> pEm;hr = pCreateDevEnum->CreateClassEnumerator(CLSID_VideoInputDeviceCategory,&pEm, 0);if (hr != NOERROR) {return count;}pEm->Reset();ULONG cFetched;IMoniker *pM;while(hr = pEm->Next(1, &pM, &cFetched), hr==S_OK){count++;}pCreateDevEnum = NULL;pEm = NULL;return count;}int CCameraDS::CameraName(int nCamID, char* sName, int nBufferSize){int count =0;CoInitialize(NULL);// enumerate all video capture devicesCComPtr<</span>ICreateDevEnum> pCreateDevEnum;HRESULT hr = CoCreateInstance(CLSID_SystemDeviceEnum, NULL, CLSCTX_INPROC_SERVER,IID_ICreateDevEnum, (void**)&pCreateDevEnum);CComPtr<</span>IEnumMoniker> pEm;hr = pCreateDevEnum->CreateClassEnumerator(CLSID_VideoInputDeviceCategory,&pEm, 0);if (hr != NOERROR) return0;pEm->Reset();ULONG cFetched;IMoniker *pM;while(hr = pEm->Next(1, &pM, &cFetched), hr==S_OK){if (count == nCamID){IPropertyBag *pBag=0;hr = pM->BindToStorage(0, 0, IID_IPropertyBag, (void**)&pBag);if(SUCCEEDED(hr)){VARIANT var;var.vt = VT_BSTR;hr = pBag->Read(L"FriendlyName", &var, NULL); //还有其他属性,像描述信息等等...if(hr == NOERROR){//获取设备名称 WideCharToMultiByte(CP_ACP,0,var.bstrVal,-1,sName, nBufferSize ,"",NULL);SysFreeString(var.bstrVal); }pBag->Release();}pM->Release();break;}count++;}pCreateDevEnum = NULL;pEm = NULL;return1;}
