Opencv在MFC客户端的Picture控件上显示图片

网上看了部分代码，但是觉得或多或少有些坐标位置上的错误，特别明显是体现在GetWindowRect这个API上，MSDN中说他返回的坐标是以屏幕左上角为基点。所以在对话框中必须先转换成基于客户端的坐标，方法是调用ScreenToClient，然后才能够调用CvvImage::DrawToHDC函数。具体步骤如下

typedef struct
{

    CDlg * pDlg;

}PARAMETER, *PPARAMETER;

void ShowImage(IplImage * img, void * p)
{    
    PPARAMETER param = (PPARAMETER)p;

    CDlg * pDigitDlg = param->pDlg;

    //Opencv自带类
    CvvImage cimg;

    cimg.CopyOf(img);

    CDC *pDC = pDigitDlg->GetDC();

    HDC hDC=  pDC->GetSafeHdc();

    RECT rect;

    //获得picture控件的屏幕坐标，IDC_STATIC_PICTURE是图片控件的ID
    pDigitDlg->GetDlgItem(IDC_STATIC_PICTURE)->GetWindowRect(&rect);

    POINT point;

    point.x = rect.left;

    point.y = rect.top;

    //调整屏幕坐标到客户端坐标
    ScreenToClient(pDigitDlg->m_hWnd,&point);

    RECT rect2 = rect;

    rect.top = point.y;

    rect.bottom = point.y + (rect2.bottom - rect2.top);

    rect.left = point.x;

    rect.right = point.x + (rect2.right - rect2.left);

    //CvvImage::DrawToHDC第二参数需要相对客户端的坐标
    cimg.DrawToHDC(hDC,&rect);  

    pDigitDlg->ReleaseDC(pDC);

    //无需显示重绘
    //pDigitDlg->InvalidateRect(&rect,TRUE);
    //pDigitDlg->UpdateWindow(); 

}