windows截屏

 1 #ifndef _CAPTURESCREEN_H
 2 #define _CAPTURESCREEN_H
 3 
 4 #include <windows.h>
 5 class  CaptureScreen
 6 {
 7 public:
 8     CaptureScreen()
 9     {};
10     ~CaptureScreen(void)
11     {};
12 
13     void ScreenInit();
14     void ScreenFree();
15     bool ScreenSetWindow(LPRECT lpRect); 
16     bool ScreenCopy(BYTE *dstBuf); 
17 
18     int rHeight;    //要获得的图像尺寸
19     int rWidth;
20 private:    
21     int nScreenWidth;
22     int nScreenHeight;
23     PRGBTRIPLE scan0;
24     BITMAPINFO pbi;
25     int stride;    
26     int top_x;
27     int top_y;
28     int bot_x;
29     int bot_y;
30 };
31 
32 #endif

 1 #include "CaptureScreen.h"
 2 
 3 void CaptureScreen::ScreenInit()
 4 {    
 5     nScreenWidth = GetSystemMetrics(SM_CXSCREEN);
 6     nScreenHeight = GetSystemMetrics(SM_CYSCREEN);
 7 
 8     pbi.bmiHeader.biSize = sizeof(BITMAPINFOHEADER);
 9     pbi.bmiHeader.biWidth = nScreenWidth;
10     pbi.bmiHeader.biHeight = nScreenHeight;
11     pbi.bmiHeader.biPlanes = 1;
12     pbi.bmiHeader.biBitCount = 24;
13     pbi.bmiHeader.biCompression = BI_RGB;
14     stride = ((nScreenWidth * 24 + 31) & 0xffffffe0) / 8;  // 24位图像扫描线宽度
15     scan0 = (PRGBTRIPLE)malloc(stride * nScreenHeight);    // 图像数据缓冲区，应释放
16 }
17 
18 void CaptureScreen::ScreenFree()
19 {
20     free(scan0); 
21 }
22 
23 bool CaptureScreen::ScreenSetWindow(LPRECT lpRect)
24 {
25      top_x = lpRect->left;
26      top_y = lpRect->top;
27      bot_x = lpRect->right;
28      bot_y = lpRect->bottom;
29     if(top_x >= bot_x)
30     return false;
31     if(top_y >= bot_y)
32     return false;
33     if(top_x<0 || bot_x>nScreenWidth)
34     return false;
35     if(top_y<0 || bot_y>nScreenHeight)
36     return false;
37 
38     rHeight = bot_y-top_y;
39     rWidth =  bot_x-top_x;    
40     return true;
41 }
42 
43 bool CaptureScreen::ScreenCopy(BYTE *dstBuf)
44 {    
45     HWND hDesktopWnd = GetDesktopWindow();
46     HDC hDesktopDC = GetDC(hDesktopWnd);
47     HDC hCaptureDC = CreateCompatibleDC(hDesktopDC);
48     HBITMAP hCaptureBitmap =CreateCompatibleBitmap(hDesktopDC,nScreenWidth, nScreenHeight);
49     SelectObject(hCaptureDC,hCaptureBitmap);
50     BitBlt(hCaptureDC,0,0,nScreenWidth,nScreenHeight,hDesktopDC,0,0,SRCCOPY|NOMIRRORBITMAP);
51     DeleteDC(hCaptureDC);
52 
53     GetDIBits(hDesktopDC, hCaptureBitmap, 0, nScreenHeight, scan0, &pbi, DIB_RGB_COLORS);
54     ReleaseDC(hDesktopWnd,hDesktopDC);
55     DeleteObject(hCaptureBitmap);
56 
57     BYTE *srcBuf = (BYTE*) scan0;
58 
59     int j;
60     srcBuf += (nScreenHeight-1-top_y)*stride+top_x*3;// scan0倒序
61     for(j=0;j<rHeight;j++)
62     {
63         memcpy(dstBuf,srcBuf,rWidth*3);
64         dstBuf += rWidth*3;
65         srcBuf -= stride;
66     }
67     return true;
68 }

 1 #include "CaptureScreen.h"
 2 #include <stdio.h> 
 3 #include <Mmsystem.h>
 4 #pragma comment( lib,"winmm.lib" )
 5 void SaveBmp2(BYTE *bgr32,int w,int h,int mode)
 6 {
 7     
 8     /////////////////////////////////////////////
 9     DWORD size=w*h*3;
10     LPSTR lpData=(LPSTR)GlobalAlloc(GPTR,size);
11     /////////////////////////////////////////////
12     BITMAPINFOHEADER bih;
13     bih.biSize=sizeof(BITMAPINFOHEADER);
14     bih.biWidth=w;
15     bih.biHeight=h;
16     bih.biPlanes=1;
17     bih.biBitCount=24;
18     bih.biCompression=0;
19     bih.biSizeImage=w*h*3;//size;
20     bih.biXPelsPerMeter=0;
21     bih.biYPelsPerMeter=0;
22     bih.biClrUsed=0;
23     bih.biClrImportant=0;
24     
25     BITMAPFILEHEADER bfh;
26     bfh.bfType=0x4D42;  // "BM"      // 设置位图文件头
27        bfh.bfReserved1=bfh.bfReserved2=0;
28     bfh.bfSize=54+size;
29     bfh.bfOffBits=54;
30 
31     if(mode == 0)
32     {
33     for(int i=0;i<h;i++)
34     {
35         memcpy(lpData+(h-1-i)*w*3,bgr32+i*w*3,w*3);
36     }
37     }
38     else
39         memcpy(lpData,bgr32,w*h*3);
40     
41     static int filecount=0;
42     char filename[255];
43     sprintf(filename,"C:\%d.bmp",filecount);
44     FILE *fp=fopen(filename,"wb");
45 
46     if(fp)
47     {
48          
49         fwrite(&bfh,1,sizeof(BITMAPFILEHEADER),fp);
50         fwrite(&bih,1,sizeof(BITMAPINFOHEADER),fp);
51         fwrite(lpData,1,size,fp);
52         fclose(fp);
53         filecount++;
54     }
55     GlobalFree(lpData);
56 
57 }
58 
59 int main()
60 {
61     
62     CaptureScreen myCapture;
63     myCapture.ScreenInit();
64     RECT dstRect={0,0,1920,1080};
65     myCapture.ScreenSetWindow(&dstRect);
66     BYTE *dstBuff = (BYTE*)malloc(myCapture.rWidth*myCapture.rHeight*3);
67     int lastTime = timeGetTime();
68     myCapture.ScreenCopy(dstBuff);
69     printf("time:%dms",timeGetTime()-lastTime);
70     SaveBmp2((BYTE*)dstBuff,myCapture.rWidth,myCapture.rHeight,0);
71     myCapture.ScreenFree();
72 
73     
74     return 0;
75 }