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 <vector> using namespace std;
添加公共变量和方法
vector<CCameraDS> cameralist; CImage *m_pImage; void ShowPicture(CImage *img,CStatic *pic); void SaveCard(CImage *img); int m_cam_count; bool isBreak; CString m_savePath; CString savePath; int m_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<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 ; } int width = 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_64
2
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 __ptr64
6 typedef unsigned __int64 POINTER_64_INT;
7 #if defined(_WIN64)
8 #define POINTER_32 __ptr32
9 #else
10 #define POINTER_32
11 #endif
12 #else
13 #if defined(_MAC) && defined(_MAC_INT_64)
14 #define POINTER_64 __ptr64
15 typedef unsigned __int64 POINTER_64_INT;
16 #else
17 #if (_MSC_VER >= 1300) && !(defined(MIDL_PASS) || defined(RC_INVOKED))
18 #define POINTER_64 __ptr64
19 #else
20 #define POINTER_64
21 #endif
22 typedef unsigned long POINTER_64_INT;
23 #endif
24 #define POINTER_32
25 #endif
26
27 #endif
28
29
30
31
32
33 #ifndef CCAMERA_H
34 #define CCAMERA_H
35
36 #define WIN32_LEAN_AND_MEAN
37
38 #include <atlbase.h>
39 #include "qedit.h"
40 #include "dshow.h"
41 #include <windows.h>
42 //#include "cv.h"
43
44 //#include <cxcore.h>
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<IGraphBuilder> m_pGraph;
71 CComPtr<IBaseFilter> m_pDeviceFilter;
72 CComPtr<IMediaControl> m_pMediaControl;
73 CComPtr<IBaseFilter> m_pSampleGrabberFilter;
74 CComPtr<ISampleGrabber> m_pSampleGrabber;
75 CComPtr<IPin> m_pGrabberInput;
76 CComPtr<IPin> m_pGrabberOutput;
77 CComPtr<IPin> m_pCameraOutput;
78 CComPtr<IMediaEvent> m_pMediaEvent;
79 CComPtr<IBaseFilter> m_pNullFilter;
80 CComPtr<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false
93 bool CCameraDS::OpenCamera(int nCamID, bool bDisplayProperties=true, int nWidth =320, int nHeight =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 #endif
camera.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 in
BindFilter(nCamID, &m_pDeviceFilter);
m_pGraph->AddFilter(m_pDeviceFilter, NULL);
CComPtr<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<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<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 <0)
returnfalse;
// enumerate all video capture devices
CComPtr<ICreateDevEnum> pCreateDevEnum;
HRESULT hr = CoCreateInstance(CLSID_SystemDeviceEnum, NULL, CLSCTX_INPROC_SERVER,
IID_ICreateDevEnum, (void**)&pCreateDevEnum);
if (hr != NOERROR)
{
returnfalse;
}
CComPtr<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_Composite
void 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<InputPinCount;i++)
{
pXBar1->get_CrossbarPinInfo(TRUE,i,&PinIndexRelated,&PhysicalType);
if(PhysConn_Video_Composite==PhysicalType)
{
inPort = i;
break;
}
}
for( i =0;i<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();
}
/*
The returned image can not be released.
//*/
//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()
{
/*if(!m_image.IsNull())
{
m_image.Destroy();
}*/
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_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<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 devices
CComPtr<ICreateDevEnum> pCreateDevEnum;
HRESULT hr = CoCreateInstance(CLSID_SystemDeviceEnum, NULL, CLSCTX_INPROC_SERVER,
IID_ICreateDevEnum, (void**)&pCreateDevEnum);
CComPtr<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 devices
CComPtr<ICreateDevEnum> pCreateDevEnum;
HRESULT hr = CoCreateInstance(CLSID_SystemDeviceEnum, NULL, CLSCTX_INPROC_SERVER,
IID_ICreateDevEnum, (void**)&pCreateDevEnum);
CComPtr<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;
}