OpenCV4.1 显示图像到MFC Pictrue控件

秒速五厘米 2023-05-31 12:17 5阅读 0赞

新版本的opencv取消了CvvImage，然而就不支持在MFC中显示了。这里介绍一种新的显示图像的方法。

环境：OpenCV4.1 +MCF 对话框 +Picture控件

方法一：直接将Mat显示在Picture窗体上

显示函数定义如下，

// MFC上Picture Control控件显示图像
    
    // src 待显示的图像 (OpenCV库Mat对象结构)
    
    // hwnd MFC显示图像的窗口句柄
    
    void CXXXDlg::ShowImage(Mat& imgSrc, HWND hwnd) {
    
             HDC hdc = ::GetDC(hwnd);
    
             CRect rect;
    
             //获取图片控件矩形框
    
             GetDlgItem(IDC_STATIC_SHOWIMAGE)->GetClientRect(&rect);
    
             //缩放Mat，以适应图片控件大小
    
             cv::resize(imgSrc, imgSrc, cv::Size(rect.Width(), rect.Height()));
    
             //cv::resize(imgSrc, imgSrc, cv::Size(300, 300));
    
             // 转换格式 ,便于获取BITMAPINFO
    
             switch (imgSrc.channels())
    
             {
    
             case 1:
    
                       cv::cvtColor(imgSrc, imgSrc, COLOR_GRAY2BGRA); // GRAY单通道
    
                       break;
    
             case 3:
    
                       cv::cvtColor(imgSrc, imgSrc, COLOR_BGR2BGRA);  // BGR三通道
    
                       break;
    
             default:
    
                       break;
    
             }
    
             // 计算一个像素多少个字节
    
             int pixelBytes = imgSrc.channels()*(imgSrc.depth() + 1);
    
             // 制作bitmapinfo(数据头)
    
             BITMAPINFO bitInfo;
    
             bitInfo.bmiHeader.biBitCount = 8 * pixelBytes;
    
             bitInfo.bmiHeader.biWidth = imgSrc.cols;
    
             bitInfo.bmiHeader.biHeight = -imgSrc.rows;   //注意"-"号(正数时倒着绘制)
    
             bitInfo.bmiHeader.biPlanes = 1;
    
             bitInfo.bmiHeader.biSize = sizeof(BITMAPINFOHEADER);
    
             bitInfo.bmiHeader.biCompression = BI_RGB;
    
             bitInfo.bmiHeader.biClrImportant = 0;
    
             bitInfo.bmiHeader.biClrUsed = 0;
    
             bitInfo.bmiHeader.biSizeImage = 0;
    
             bitInfo.bmiHeader.biXPelsPerMeter = 0;
    
             bitInfo.bmiHeader.biYPelsPerMeter = 0;
    
             CDC *pDC = GetDlgItem(IDC_STATIC_SHOWIMAGE)->GetDC();  //获取图片控件DC
    
             //绘图
    
             ::StretchDIBits(
    
                       pDC->GetSafeHdc(),
    
                       0, 0, rect.Width(), rect.Height(),
    
                       0, 0, imgSrc.cols, imgSrc.rows,
    
                       imgSrc.data,
    
                       &bitInfo,
    
                       DIB_RGB_COLORS,
    
                       SRCCOPY
    
             );
    
             ReleaseDC(pDC);  //释放DC
    
    }

函数调用方法：

HWND hwnd = GetDlgItem(IDC_STATIC_SHOWIMAGE)->GetSafeHwnd();
    // 获取显示的图像
    Mat img = imread("D:/images/11111.jpg");
    // 调用显示函数
    ShowImage(img, hwnd);

方法二：用Mat转CImage的方式，然后在Pictrue控件上绘制CImage

Mat转CImage

void CXXXDlg::MatToCImage(Mat &mat, CImage &cImage)
    
    {
    
             //create new CImage 
             int width = mat.cols;
             int height = mat.rows;
             int channels = mat.channels();
             cImage.Destroy(); //clear 
             cImage.Create(width, height, 8 * channels); //默认图像像素单通道占用1个字节 
    
             //copy values 
             uchar* ps;
             uchar* pimg = (uchar*)cImage.GetBits(); //A pointer to the bitmap buffer 
             int step = cImage.GetPitch();
             for (int i = 0; i < height; ++i)
    
             {
                       ps = (mat.ptr<uchar>(i));
                       for (int j = 0; j < width; ++j)
                       {
                                if (channels == 1) //gray 
    
                                {
                                         *(pimg + i * step + j) = ps[j];
                                }
                                else if (channels == 3) //color 
                                {
                                         for (int k = 0; k < 3; ++k)
                                         {
                                                   *(pimg + i * step + j * 3 + k) = ps[j * 3 + k];
                                         }
                                }
                       }
             }
    }

函数调用示例：

void CXXXDlg::ShowMethord4()
    
    {
    
             int cxl, cyl;
    
             Mat rgbImageL1 = imread("D:/images/11111.jpg");//opencv图片
    
             CImage  rgbImageL2;
    
             CRect   rectl, pic_rectl;
    
             int widthl, heightl;
    
             //改变图片大小适应picture控件
    
             GetDlgItem(IDC_STATIC_SHOWIMAGE)->GetClientRect(&pic_rectl);
    
             widthl = pic_rectl.right;
    
             heightl = pic_rectl.bottom;
    
             resize(rgbImageL1, rgbImageL1, Size(widthl, heightl));
    
             MatToCImage(rgbImageL1, rgbImageL2);//OpenCV中Mat对象转MFC的CImage类的函数
    
             //获取图片的宽 高度 
    
             cxl = rgbImageL2.GetWidth();
    
             cyl = rgbImageL2.GetHeight();
    
             //获取Picture Control控件的大小 
    
             GetDlgItem(IDC_STATIC_SHOWIMAGE)->GetWindowRect(&rectl);
    
             //将客户区选中到控件表示的矩形区域内 
    
             ScreenToClient(&rectl);
    
             //窗口移动到控件表示的区域 
    
             GetDlgItem(IDC_STATIC_SHOWIMAGE)->MoveWindow(rectl.left, rectl.top, cxl, cyl, TRUE);
    
             CWnd *pWnd = NULL;
    
             pWnd = GetDlgItem(IDC_STATIC_SHOWIMAGE);//获取控件句柄 
    
             pWnd->GetClientRect(&rectl);//获取句柄指向控件区域的大小 
    
             CDC *pDc = NULL;
    
             pDc = pWnd->GetDC();//获取picture的DC 
    
             rgbImageL2.Draw(pDc->m_hDC, rectl);//将图片绘制到picture表示的区域内 
    
             ReleaseDC(pDc);
    
    }