CODEWITHSUNDEEP
c++windowsscreenshot
user4371190
user4371190

Reputation:

Capturing Entire ScreenShot Of PC in WIndows 8.1

I'm making a C++ program which takes screenshot of the entire screen. I am facing quite a problem. When I run the program, it takes screenshot of the console screen only, not the entire desktop.

 HDC Screen = CreateDC(L"DISPLAY", NULL, NULL, NULL);
    HDC Capture = CreateCompatibleDC(Screen);
    int width = GetDeviceCaps(Screen, HORZRES);
    int height = GetDeviceCaps(Screen, VERTRES);
    LPBYTE lpcapture;
    BITMAPINFO bmiCapture = 
    { {        sizeof(BITMAPINFOHEADER),width,height,1,24,BI_RGB,0,0,0,0,0 } };
    HBITMAP hbmCapture = CreateDIBSection(Screen, &bmiCapture, DIB_RGB_COLORS, (LPVOID *)&lpcapture, NULL, 0);
    if (hbmCapture)
    {
        HBITMAP hbmOld = (HBITMAP) SelectObject(Capture, Capture);
        BitBlt(Capture, 0, 0, width, height, Screen, 0, 0, SRCCOPY);
        SelectObject(Capture, hbmOld);
    }
    DeleteDC(Capture);
    DeleteDC(Screen);
    return hbmCapture;

Upvotes: 2

Views: 398

Answers (1)

Barmak Shemirani
Barmak Shemirani

Reputation: 31599

This should work in a console program, but it would show black console screen in the middle

int ScreenCapture(const char* fname)
{
    int result = 0; 
    HWND hWnd = GetDesktopWindow();
    HBITMAP hbmScreen = NULL;
    HDC hdcScreen = GetDC(NULL);
    HDC hdcWindow = GetDC(hWnd);
    int w = GetSystemMetrics(SM_CXSCREEN);
    int h = GetSystemMetrics(SM_CYSCREEN);

    HDC hdcMemDC = CreateCompatibleDC(hdcWindow);
    if (!hdcMemDC) goto cleanup;

    hbmScreen = CreateCompatibleBitmap(hdcWindow, w, h);
    if (!hbmScreen) goto cleanup;

    SelectObject(hdcMemDC, hbmScreen);
    if (!BitBlt(hdcMemDC, 0, 0, w, h, hdcWindow, 0, 0, SRCCOPY)) goto cleanup;

    BITMAPFILEHEADER   bmfHeader;
    BITMAPINFOHEADER   bi;

    bi.biSize = sizeof(BITMAPINFOHEADER);
    bi.biWidth = w;
    bi.biHeight = h;
    bi.biPlanes = 1;
    bi.biBitCount = 32;
    bi.biCompression = BI_RGB;
    bi.biSizeImage = 0;
    bi.biXPelsPerMeter = 0;
    bi.biYPelsPerMeter = 0;
    bi.biClrUsed = 0;
    bi.biClrImportant = 0;

    DWORD dwBmpSize = ((w * bi.biBitCount + 31) / 32) * 4 * h;

    HANDLE hDIB = GlobalAlloc(GHND, dwBmpSize);
    char* lpbitmap = (char*)GlobalLock(hDIB);

    GetDIBits(hdcWindow, hbmScreen, 0, h, lpbitmap, (BITMAPINFO*)&bi, DIB_RGB_COLORS);

    bmfHeader.bfOffBits = (DWORD)sizeof(BITMAPFILEHEADER) + (DWORD)sizeof(BITMAPINFOHEADER);
    bmfHeader.bfSize = dwBmpSize + sizeof(BITMAPFILEHEADER) + sizeof(BITMAPINFOHEADER);
    bmfHeader.bfType = 0x4D42; //'BM' for Bitmaps

    DWORD temp = 0;
    HANDLE hFile = CreateFileA(fname, GENERIC_WRITE, 0, NULL, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL);
    WriteFile(hFile, (LPSTR)&bmfHeader, sizeof(BITMAPFILEHEADER), &temp, NULL);
    WriteFile(hFile, (LPSTR)&bi, sizeof(BITMAPINFOHEADER), &temp, NULL);
    WriteFile(hFile, (LPSTR)lpbitmap, dwBmpSize, &temp, NULL);
    CloseHandle(hFile); 

    GlobalUnlock(hDIB); 
    GlobalFree(hDIB);

    result = 1; //success

cleanup:
    DeleteObject(hbmScreen);
    DeleteObject(hdcMemDC);
    ReleaseDC(NULL, hdcScreen);
    ReleaseDC(hWnd, hdcWindow);

    return result;
}

Upvotes: 2

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