[图像处理] MFC载入图片并进行二值化处理和灰度处理及其效果显示

工程效果

载入图片，并在左侧显示原始图片、二值化图片和灰度图片。
双击左侧的图片控件，可以在右侧的大控件中，显示双击的图片。

初始画面：

载入图片：

双击左侧的第二个控件，显示图片：

//对图片显示在控件中的位置没有进行优化。

重要代码

主要是用的MFC Image控件。

载入图片：

void CGDITESTDlg::OnBnClickedBtnStart()
{//获取图像文件CFileDialog filedlg(TRUE,_T("png"),NULL,0,TEXT("image Files(*.bmp;*.jpg;*.png)|*.bmp;*.jpg;*.png|all files(*.*)|(*.*)||"),this);filedlg.DoModal();m_cstr_filepath = filedlg.GetPathName();m_cstr_filename = filedlg.GetFileName();if (m_cstr_filepath.IsEmpty() || m_cstr_filename.IsEmpty()){AfxMessageBox(TEXT("打开文件失败"));return ;}	image_origin.Load(m_cstr_filepath);image_binarization.Load(m_cstr_filepath);image_grey.Load(m_cstr_filepath);//获取图像尺寸imgw = image_origin.GetWidth();imgh = image_origin.GetHeight();img_t = imgw / imgh;//根据图像尺寸，调整控件客户区尺寸比例CRect rect_ctl;m_ctl_pic_origin.GetClientRect(&rect_ctl);float rectw = rect_ctl.Width();float recth = rect_ctl.Height();float rect_t = rectw / recth;if(rect_t < img_t){rect_ctl = CRect(rect_ctl.TopLeft(), CSize(rect_ctl.Width(), rect_ctl.Width() / img_t ));}else{rect_ctl = CRect(rect_ctl.TopLeft(), CSize(rect_ctl.Height() * img_t, rect_ctl.Height()));}//显示图像到控件客户区CDC* pdc = m_ctl_pic_origin.GetDC();m_ctl_pic_origin.SetBitmap(NULL);	image_origin.Draw(pdc->m_hDC, rect_ctl);//图像二值化处理ImageBinarizationProcess(image_binarization);//根据图像尺寸，调整控件客户区尺寸比例CRect rect_ctl_binarization;m_ctl_pic_binarization.GetClientRect(&rect_ctl_binarization);float rectw_ = rect_ctl_binarization.Width();float recth_ = rect_ctl_binarization.Height();float rect_t_ = rectw / recth;if (rect_t_ < img_t){rect_ctl_binarization = CRect(rect_ctl_binarization.TopLeft(), CSize(rect_ctl_binarization.Width(), rect_ctl_binarization.Width() / img_t));}else{rect_ctl_binarization = CRect(rect_ctl_binarization.TopLeft(), CSize(rect_ctl_binarization.Height() * img_t, rect_ctl_binarization.Height()));}//显示图像到控件客户区CDC* pdc_ = m_ctl_pic_binarization.GetDC();m_ctl_pic_binarization.SetBitmap(NULL);image_binarization.Draw(pdc_->m_hDC, rect_ctl_binarization);//图像灰度处理ImageGreyProcess(image_grey);//根据图像尺寸，调整控件客户区尺寸比例CRect rect_ctl_grey;m_ctl_pic_grey.GetClientRect(&rect_ctl_grey);float rectw__ = rect_ctl_grey.Width();float recth__ = rect_ctl_grey.Height();float rect_t__ = rectw / recth;if (rect_t__ < img_t){rect_ctl_grey = CRect(rect_ctl_grey.TopLeft(), CSize(rect_ctl_grey.Width(), rect_ctl_grey.Width() / img_t));}else{rect_ctl_grey = CRect(rect_ctl_grey.TopLeft(), CSize(rect_ctl_grey.Height() * img_t, rect_ctl_grey.Height()));}//显示图像到控件客户区CDC* pdc__ = m_ctl_pic_grey.GetDC();m_ctl_pic_grey.SetBitmap(NULL);image_grey.Draw(pdc__->m_hDC, rect_ctl_grey);isLoadedImage = true;m_ctl_pic_origin.ReleaseDC(pdc);m_ctl_pic_binarization.ReleaseDC(pdc);m_ctl_pic_grey.ReleaseDC(pdc);
}

图像二值化处理：
算法来源：C++MFC打开图片、彩图,以及对图像进行简单算法处理

void CGDITESTDlg::ImageBinarizationProcess(CImage &image)
{BYTE* pimagedata = (BYTE*)image.GetBits();	//获取到图片内存点的位置int width = image.GetWidth();int height = image.GetHeight();int pit = image.GetPitch();//图像每行字节数int bytes_per_pixel = image.GetBPP() / 8; //获取每像素的位数除以8得到每个像素占的字节数std::vector<int> gray(256); //初始化时自动存0，用来存放256种颜色出现的次数for (int i = 0; i < height; i++){for (int j = 0; j < width; j++){gray.at((int)*(pimagedata + pit * i + bytes_per_pixel * j)) += 1;}}int max = 0;int sec = 0;int localmax = 0;int localsec = 0;for (int i = 0; i < 256; i++){if (gray[i] > max){max = gray[i];localmax = i;}}for (int i = 0; i < 256; i++){if (gray[i] > sec && abs(i - localmax) > 10){sec = gray[i];localsec = i;}}int mid = (localmax + localsec) / 2;for (int i = 0; i < height; i++){for (int j = 0; j < width; j++){if ((int)(*(pimagedata + pit * i + j * bytes_per_pixel)) < mid){*(pimagedata + pit * i + j * bytes_per_pixel) = 0;*(pimagedata + pit * i + j * bytes_per_pixel + 1) = 0;*(pimagedata + pit * i + j * bytes_per_pixel + 2) = 0;}else{*(pimagedata + pit * i + j * bytes_per_pixel) = 255;*(pimagedata + pit * i + j * bytes_per_pixel + 1) = 255;*(pimagedata + pit * i + j * bytes_per_pixel + 2) = 255;}}}
}

灰度处理：
算法来源：C++MFC打开图片、彩图,以及对图像进行简单算法处理

void CGDITESTDlg::ImageGreyProcess(CImage& image)
{BYTE* pimagedata = (BYTE*)image.GetBits();	//获取到图片内存点的位置int width = image.GetWidth();int height = image.GetHeight();int pit = image.GetPitch();//图像每行字节数int bytes_per_pixel = image.GetBPP() / 8; //获取每像素的位数除以8得到每个像素占的字节数for (int i = 0; i < height; i++){for (int j = 0; j < width; j++){*(pimagedata + pit * i + j * bytes_per_pixel) *= 0.114;*(pimagedata + pit * i + j * bytes_per_pixel + 1) *= 0.587;*(pimagedata + pit * i + j * bytes_per_pixel + 2) *= 0.299;}}}

双击左侧控件的响应：

void CGDITESTDlg::OnLButtonDblClk(UINT nFlags, CPoint point)
{if (!isLoadedImage) //如果没有加载图片，则不会执行后续代码return;//未使用，仅测试CPoint ptCursor;GetCursorPos(&ptCursor);//获取执行此函数时的鼠标位置，屏幕坐标ClientToScreen(&point); //point是双击时的鼠标位置，坐标系是窗口客户区，所以要转换成屏幕坐标//未使用，仅测试CPoint ptCursor1(GetCurrentMessage()->pt); //双击时的鼠标位置，屏幕坐标GetDlgItem(IDC_PIC_ORIGIN)->GetWindowRect(&rc_origin);//控件的rect，屏幕坐标if (rc_origin.PtInRect(point))//如果右键在picture control区域抬起则放大显示灰度图片{CRect rect_ctl;m_ctl_pic_dsp.GetClientRect(&rect_ctl);float rectw = rect_ctl.Width();float recth = rect_ctl.Height();float rect_t = rectw / recth;if (rect_t < img_t){rect_ctl = CRect(rect_ctl.TopLeft(), CSize(rect_ctl.Width(), rect_ctl.Width() / img_t));}else{rect_ctl = CRect(rect_ctl.TopLeft(), CSize(rect_ctl.Height() * img_t, rect_ctl.Height()));}CDC* pdc = m_ctl_pic_dsp.GetDC();m_ctl_pic_dsp.SetBitmap(NULL);image_origin.Draw(pdc->m_hDC, rect_ctl);m_ctl_pic_dsp.ReleaseDC(pdc);return;}GetDlgItem(IDC_PIC_PROCESS)->GetWindowRect(&rc_binarization);if (rc_binarization.PtInRect(point))//如果右键在picture control区域抬起则放大显示灰度图片{CRect rect_ctl;m_ctl_pic_dsp.GetClientRect(&rect_ctl);float rectw = rect_ctl.Width();float recth = rect_ctl.Height();float rect_t = rectw / recth;if (rect_t < img_t){rect_ctl = CRect(rect_ctl.TopLeft(), CSize(rect_ctl.Width(), rect_ctl.Width() / img_t));}else{rect_ctl = CRect(rect_ctl.TopLeft(), CSize(rect_ctl.Height() * img_t, rect_ctl.Height()));}CDC* pdc = m_ctl_pic_dsp.GetDC();m_ctl_pic_dsp.SetBitmap(NULL);image_binarization.Draw(pdc->m_hDC, rect_ctl);m_ctl_pic_dsp.ReleaseDC(pdc);return;}GetDlgItem(IDC_PIC_PROCESS2)->GetWindowRect(&rc_grey);if (rc_grey.PtInRect(point))//如果右键在picture control区域抬起则放大显示灰度图片{CRect rect_ctl;m_ctl_pic_dsp.GetClientRect(&rect_ctl);float rectw = rect_ctl.Width();float recth = rect_ctl.Height();float rect_t = rectw / recth;if (rect_t < img_t){rect_ctl = CRect(rect_ctl.TopLeft(), CSize(rect_ctl.Width(), rect_ctl.Width() / img_t));}else{rect_ctl = CRect(rect_ctl.TopLeft(), CSize(rect_ctl.Height() * img_t, rect_ctl.Height()));}CDC* pdc = m_ctl_pic_dsp.GetDC();m_ctl_pic_dsp.SetBitmap(NULL);image_grey.Draw(pdc->m_hDC, rect_ctl);m_ctl_pic_dsp.ReleaseDC(pdc);return;}CDialogEx::OnLButtonDblClk(nFlags, point);
}

以上是通过窗口的双击时间回调函数，判断双击时鼠标的坐标，是否在控件的坐标Rect中，如果是，则执行对应代码。

也可以把双击的空间的notify属性设置为true，然后再时间中设置双击消息回调函数。

完整代码

MFC简单的图片处理工程-Gitee

参考

C++MFC打开图片、彩图,以及对图像进行简单算法处理