MFC+Opencv显示图像的几种方法

原文地址：http://blog.csdn.net/u012250337/article/details/51601905

（1）使用opencv的CvvImage类

该方法比较简单，但是opencv2.x以上版本已经不支持CvvImage类，不过可以在网上下载该类的头文件和源文件，添加到工程里就可以使用了。

 void CXXXDlg::DrawIplImage2MFC(IplImage* img, unsigned int id)
 {
     CDC* pDC = GetDlgItem(id)->GetDC();
     HDC hDC = pDC->GetSafeHdc();
     CvvImage cimg;
     cimg.CopyOf( img );
     CRect rect;
     GetDlgItem(id)->GetClientRect(&rect);
     cimg.DrawToHDC(hDC, &rect);
     ReleaseDC( pDC );
 }

函数参数中id是控件ID，比如IDC_STATIC（下同）。

（2）使用MFC的绘图函数
该方法利用MFC的绘图函数，将opencv图像数据先copy到缓冲去然后在控件上显示出来。

 void CXXXDlg::DrawIplImage2MFC(IplImage* img, unsigned int id)
 {
     BYTE *g_pBits;
      HDC g_hMemDC;
      HBITMAP g_hBmp, g_hOldBmp;
      CDC *pDC;
      CStatic *pic;
      int width, height;
      CRect rect;
      pDC = GetDlgItem(id)->GetDC();
      pic = (CStatic*)GetDlgItem(id);
      pic->GetClientRect(&rect);
      width = rect.Width();
      height = rect.Height();
      g_hMemDC =::CreateCompatibleDC(pDC->m_hDC);
      BYTE bmibuf[sizeof(BITMAPINFO)+256 * sizeof(RGBQUAD)];
      memset(bmibuf, 0, sizeof(bmibuf));
      BITMAPINFO *pbmi = (BITMAPINFO*)bmibuf;
      pbmi->bmiHeader.biSize = sizeof(BITMAPINFOHEADER);
      pbmi->bmiHeader.biWidth = img->width;
      pbmi->bmiHeader.biHeight = img->height;
      pbmi->bmiHeader.biPlanes = 1;
      pbmi->bmiHeader.biBitCount = 24;
      pbmi->bmiHeader.biCompression= BI_RGB;
      g_hBmp =::CreateDIBSection(g_hMemDC, pbmi, DIB_RGB_COLORS, (void**)&g_pBits, 0, 0);
      g_hOldBmp = (HBITMAP)::SelectObject(g_hMemDC, g_hBmp);
      BitBlt(g_hMemDC, 0, 0, width, height, pDC->m_hDC, 0, 0, SRCCOPY);
      int l_width = WIDTHBYTES(img->width* pbmi->bmiHeader.biBitCount);
      for (int row = 0; row < img->height;row++)
      memcpy(&g_pBits[row*l_width],&img->imageData[ (img->height - row - 1)*l_width], l_width);
      TransparentBlt(pDC->m_hDC, 0, 0, width, height, g_hMemDC, 0, 0, img->width, img->height, RGB(0, 0, 0));
      SelectObject(g_hMemDC, g_hOldBmp);
      DeleteDC(g_hMemDC);
      DeleteObject(pic);
      DeleteObject(g_hBmp);
      DeleteObject(g_hOldBmp);
 }

（3）链接opencv窗口和MFC控件

该方法是将opencv的显示窗口与MFC的控件链接起来，效果是opencv的窗口恰好覆盖在控件上。

 //pic是opencv窗口的标志符，name是窗口名字，ID同上，是MFC控件ID

 bool CXXXDlg::attachWindow(string &pic,const char* name,int ID)
 {
     pic=string(name);
     cv::namedWindow(pic, 1);
     HWND hWnd = (HWND) cvGetWindowHandle(name);
     HWND hParent = ::GetParent(hWnd);
     ::SetParent(hWnd, GetDlgItem(ID)->m_hWnd);
     ::ShowWindow(hParent, SW_HIDE);
     return true;
 }

 bool CXXXDlg::showImage(string pic,int id,cv::Mat mat)
 {
     CRect rect;
     GetDlgItem(id)->GetClientRect(&rect);
     cv::resize(mat,mat,cv::Size(rect.Width(),rect.Height()),CV_INTER_CUBIC);
     imshow(pic,mat);
     return true;
 }

使用方法是先链接opencv窗口的标识符和控件ID

 string pic;
 attachWindow(pic,"win",IDC_PIC);

然后在需要显示图像的地方调用showImage

 Mat mat=imread("1.jpg");
 showImage(pic,IDC_PIC,mat);