1.1.0-学习Opencv与MFC混合编程之---全屏截图，保存为BMP图像（并增加快捷键）

源代码：http://download.csdn.net/detail/nuptboyzhb/3961677

Ø  添加全屏截图菜单项，菜单项的属性如下;

Ø  为该菜单项建立类向导。

编辑消息处理函数如下

voidCCVMFCView::OnPrintscreen()

{

        

         CRect rect;

         //HBITMAP hMap;

         rect.left = 0;

         rect.top = 0;

         rect.right =GetSystemMetrics(SM_CXSCREEN);

         rect.bottom =GetSystemMetrics(SM_CYSCREEN);

         //-------------------------------------------

         HDC hScrDC, hMemDC;     

         // 屏幕和内存设备描述表

         HBITMAP hBitmap,hOldBitmap;  

         // 位图句柄

         int       nX, nY, nX2, nY2;     

         // 选定区域坐标

         int       nWidth, nHeight;     

         // 位图宽度和高度

         int       xScrn, yScrn;        

         // 屏幕分辨率

         // 确保选定区域不为空矩形

         //为屏幕创建设备描述表

         hScrDC = CreateDC("DISPLAY",NULL, NULL, NULL);

         //为屏幕设备描述表创建兼容的内存设备描述表

         hMemDC = CreateCompatibleDC(hScrDC);

         // 获得选定区域坐标

         nX = rect.left;

         nY = rect.top;

         nX2 =rect.right;

         nY2 =rect.bottom;

         // 获得屏幕分辨率

         xScrn = GetDeviceCaps(hScrDC, HORZRES);

         yScrn = GetDeviceCaps(hScrDC, VERTRES);

         //确保选定区域是可见的

         if (nX < 0) nX = 0;

         if (nY < 0) nY = 0;

         if (nX2 > xScrn) nX2 = xScrn;

         if (nY2 > yScrn) nY2 = yScrn;

         nWidth = nX2 - nX;

         nHeight = nY2 - nY;

         // 创建一个与屏幕设备描述表兼容的位图

         hBitmap=CreateCompatibleBitmap(hScrDC,nWidth,nHeight);

         // 把新位图选到内存设备描述表中

         hOldBitmap=(HBITMAP)SelectObject(hMemDC,hBitmap);

         // 把屏幕设备描述表拷贝到内存设备描述表中

         BitBlt(hMemDC,0,0,nWidth,nHeight,hScrDC, nX, nY, SRCCOPY);

         //得到屏幕位图的句柄

         hBitmap=(HBITMAP)SelectObject(hMemDC,hOldBitmap);

         //清除

         DeleteDC(hScrDC);

         DeleteDC(hMemDC);

        

         CFileDialogdlg(false,"*.bmp","Test.bmp",OFN_HIDEREADONLY |OFN_OVERWRITEPROMPT,"保存文本(*.bmp)|*.bmp|所有文件(*.*)|*.*||");

         CString strPath("");

         if(dlg.DoModal() == IDOK)

         {

                   strPath=dlg.GetPathName();

                   //----------------以下为保存图像句柄为hBitmap，路径为lpFileName的图像

            LPSTR lpFileName=(LPTSTR)(LPCTSTR)strPath;

                   HDC  hDC;   //设备描述表   

                   int iBits;  //当前显示分辨率下每个像素所占字节数   

                   WORD    wBitCount;  //位图中每个像素所占字节数

                   //定义调色板大小， 位图中像素字节大小 ，  位图文件大小 ， 写入文件字节数

                   DWORD          dwPaletteSize=0,dwBmBitsSize,dwDIBSize, dwWritten;

                   BITMAP          Bitmap;     //位图属性结构

                   BITMAPFILEHEADER   bmfHdr; //位图文件头结构

                   BITMAPINFOHEADER   bi;     //位图信息头结构

                   LPBITMAPINFOHEADER lpbi;          //指向位图信息头结构

                   HANDLE       fh, hDib, hPal;

                   HPALETTE     hOldPal=NULL;

                   //定义文件，分配内存句柄，调色板句柄

                  

                   //计算位图文件每个像素所占字节数

                   hDC =CreateDC("DISPLAY",NULL,NULL,NULL);

                   iBits = GetDeviceCaps(hDC,BITSPIXEL) *

                            GetDeviceCaps(hDC,PLANES);

                   DeleteDC(hDC);

                   if (iBits <= 1)  wBitCount = 1;

                   else if (iBits <= 4)  wBitCount = 4;

                   else if (iBits <= 8)  wBitCount = 8;

                   else if (iBits <= 24)wBitCount = 24;

                   else

                            wBitCount = 32;

                  

                   //计算调色板大小

                   if (wBitCount <= 8) 

                            dwPaletteSize=(1<<wBitCount)*sizeof(RGBQUAD);

                  

                   //设置位图信息头结构

                   GetObject(hBitmap,sizeof(BITMAP), (LPSTR)&Bitmap);

                   bi.biSize=sizeof(BITMAPINFOHEADER);

                   bi.biWidth= Bitmap.bmWidth;

                   bi.biHeight= Bitmap.bmHeight;

                   bi.biPlanes= 1;

                   bi.biBitCount= wBitCount;

                   bi.biCompression= BI_RGB;

                   bi.biSizeImage= 0;

                   bi.biXPelsPerMeter= 0;

                   bi.biYPelsPerMeter= 0;

                   bi.biClrUsed= 0;

                   bi.biClrImportant= 0;

                   dwBmBitsSize =((Bitmap.bmWidth*wBitCount+31)/32)*4*Bitmap.bmHeight;

                   //为位图内容分配内存

                   /*xxxxxxxx计算位图大小分解一下(解释一下上面的语句)xxxxxxxxxxxxxxxxxxxx

                   //每个扫描行所占的字节数应该为4的整数倍，具体算法为:

                   int biWidth =(Bitmap.bmWidth*wBitCount) / 32;

                   if((Bitmap.bmWidth*wBitCount)% 32)

                   biWidth++; //不是整数倍的加1

                   biWidth *= 4;//到这里，计算得到的为每个扫描行的字节数。

                   dwBmBitsSize = biWidth *Bitmap.bmHeight;//得到大小

                   xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx*/

                   hDib  =GlobalAlloc(GHND,dwBmBitsSize+dwPaletteSize+sizeof(BITMAPINFOHEADER));

                   lpbi =(LPBITMAPINFOHEADER)GlobalLock(hDib);

                   *lpbi = bi;

                   // 处理调色板  

                   hPal =GetStockObject(DEFAULT_PALETTE);

                   if (hPal)

                   {

                            hDC = ::GetDC(NULL);

                            hOldPal=SelectPalette(hDC,(HPALETTE)hPal,FALSE);

                            RealizePalette(hDC);

                   }

                   // 获取该调色板下新的像素值

                   GetDIBits(hDC,hBitmap,0,(UINT)Bitmap.bmHeight,(LPSTR)lpbi+sizeof(BITMAPINFOHEADER)+dwPaletteSize,(BITMAPINFO *)lpbi,DIB_RGB_COLORS);

                   //恢复调色板  

                   if (hOldPal)

                   {

                            SelectPalette(hDC,hOldPal, TRUE);

                            RealizePalette(hDC);

                            ::ReleaseDC(NULL,hDC);

                   }

                   //创建位图文件   

                   fh=CreateFile(lpFileName,GENERIC_WRITE,0, NULL, CREATE_ALWAYS,FILE_ATTRIBUTE_NORMAL | FILE_FLAG_SEQUENTIAL_SCAN,NULL);

                   // 设置位图文件头

                   bmfHdr.bfType = 0x4D42;  // "BM"

                   dwDIBSize=sizeof(BITMAPFILEHEADER)+sizeof(BITMAPINFOHEADER)+dwPaletteSize+dwBmBitsSize; 

                   bmfHdr.bfSize = dwDIBSize;

                   bmfHdr.bfReserved1 = 0;

                   bmfHdr.bfReserved2 = 0;

                  bmfHdr.bfOffBits=(DWORD)sizeof(BITMAPFILEHEADER)+(DWORD)sizeof(BITMAPINFOHEADER)+dwPaletteSize;

                   // 写入位图文件头

                   WriteFile(fh,(LPSTR)&bmfHdr, sizeof(BITMAPFILEHEADER), &dwWritten, NULL);

                   // 写入位图文件其余内容

                   WriteFile(fh, (LPSTR)lpbi,sizeof(BITMAPINFOHEADER)+dwPaletteSize+dwBmBitsSize , &dwWritten, NULL);

                   //清除  

                   GlobalUnlock(hDib);

                   GlobalFree(hDib);

                   CloseHandle(fh);

        MessageBox("已完成保存！");

         }

}

Ø  “全屏截图”菜单项的资源ID是ID_PRINTSCREEN

Ø  打开资源：Accelerator

Ø  目前的快捷键为：

Ø  添加新的快捷键，在最后一行的虚线处，点击鼠标右键添加：属性如下

Ø  添加之后的资源界面为：

 

from:http://blog.csdn.net/nupt123456789/article/details/7100134