?
Solved

Saving a bitmap to disk

Posted on 1999-07-01
1
Medium Priority
?
605 Views
Last Modified: 2013-11-20
I have the following code to load a bitmap from the disk.

void CTheDoc::Serialize (CArchive& ar)
{
    if (ar.IsLoading ()) {
        CString strFileName = ar.GetFile ()->GetFilePath ();

        HBITMAP hBitmap = (HBITMAP) ::LoadImage (AfxGetInstanceHandle (),
            (LPCTSTR) strFileName, IMAGE_BITMAP, 0, 0, LR_LOADFROMFILE |
            LR_CREATEDIBSECTION);

        if (hBitmap == NULL)
            AfxThrowArchiveException (CArchiveException::badIndex);

        m_bitmap.Attach (hBitmap); ::MessageBeep(0);
    }
}

Where m_bitmap is declares as CBitmap.
What is the parallel code to this that would allow me to save the bitmap to disk.

Thank you
0
Comment
Question by:Zainal062797
1 Comment
 
LVL 4

Accepted Solution

by:
nil_dib earned 400 total points
ID: 1308678
before you take a look at the code below, check out:

http://www.codeguru.com/bitmap/index.shtml

The following example code defines a function that allocates memory for and initializes members within a BITMAPINFOHEADER structure.

PBITMAPINFO CreateBitmapInfoStruct(HWND hwnd, HBITMAP hBmp) {
    BITMAP bmp;
    PBITMAPINFO pbmi;
    WORD    cClrBits;
 
    /* Retrieve the bitmap's color format, width, and height. */
 
    if (!GetObject(hBmp, sizeof(BITMAP), (LPSTR)&bmp))
        errhandler("GetObject", hwnd);
 
 
    /* Convert the color format to a count of bits. */
 
    cClrBits = (WORD)(bmp.bmPlanes * bmp.bmBitsPixel);
 
    if (cClrBits == 1)
        cClrBits = 1;
    else if (cClrBits <= 4)
        cClrBits = 4;
    else if (cClrBits <= 8)
        cClrBits = 8;
    else if (cClrBits <= 16)
        cClrBits = 16;
    else if (cClrBits <= 24)
        cClrBits = 24;
    else
        cClrBits = 32;
 
    /*
     * Allocate memory for the BITMAPINFO structure. (This structure
     * contains a BITMAPINFOHEADER structure and an array of RGBQUAD data
     * structures.)
     */
 
    if (cClrBits != 24)
         pbmi = (PBITMAPINFO) LocalAlloc(LPTR,
                    sizeof(BITMAPINFOHEADER) +
                    sizeof(RGBQUAD) * (2^cClrBits));
 
    /*
     * There is no RGBQUAD array for the 24-bit-per-pixel format.
     */
 
    else
         pbmi = (PBITMAPINFO) LocalAlloc(LPTR,
                    sizeof(BITMAPINFOHEADER));
 
 
 
    /* Initialize the fields in the BITMAPINFO structure. */
 
    pbmi->bmiHeader.biSize = sizeof(BITMAPINFOHEADER);
    pbmi->bmiHeader.biWidth = bmp.bmWidth;
    pbmi->bmiHeader.biHeight = bmp.bmHeight;
    pbmi->bmiHeader.biPlanes = bmp.bmPlanes;
    pbmi->bmiHeader.biBitCount = bmp.bmBitsPixel;
    if (cClrBits < 24)
        pbmi->bmiHeader.biClrUsed = 2^cClrBits;
 
 
    /* If the bitmap is not compressed, set the BI_RGB flag. */
 
    pbmi->bmiHeader.biCompression = BI_RGB;
 
    /*
     * Compute the number of bytes in the array of color
     * indices and store the result in biSizeImage.
     */
 
    pbmi->bmiHeader.biSizeImage = (pbmi->bmiHeader.biWidth + 7) /8
                                  * pbmi->bmiHeader.biHeight
                                  * cClrBits;
 
    /*
     * Set biClrImportant to 0, indicating that all of the
     * device colors are important.
     */
 
    pbmi->bmiHeader.biClrImportant = 0;
 
    return pbmi;
 
}
 
The following example code defines a function that initializes the remaining structures, retrieves the array of palette indices, opens the file, copies the data, and closes the file.

void CreateBMPFile(HWND hwnd, LPTSTR pszFile, PBITMAPINFO pbi,
                  HBITMAP hBMP, HDC hDC)
 {
 
    HANDLE hf;                  /* file handle */
    BITMAPFILEHEADER hdr;       /* bitmap file-header */
    PBITMAPINFOHEADER pbih;     /* bitmap info-header */
    LPBYTE lpBits;              /* memory pointer */
    DWORD dwTotal;              /* total count of bytes */
    DWORD cb;                   /* incremental count of bytes */
    BYTE *hp;                   /* byte pointer */
    DWORD dwTmp;
 
 
    pbih = (PBITMAPINFOHEADER) pbi;
    lpBits = (LPBYTE) GlobalAlloc(GMEM_FIXED, pbih->biSizeImage);    if (!lpBits)
         errhandler("GlobalAlloc", hwnd);
 
    /*
     * Retrieve the color table (RGBQUAD array) and the bits
     * (array of palette indices) from the DIB.
     */
 
    if (!GetDIBits(hDC, hBMP, 0, (WORD) pbih->biHeight,
                   lpBits, pbi, DIB_RGB_COLORS))
        errhandler("GetDIBits", hwnd);
 
    /* Create the .BMP file. */
 
    hf = CreateFile(pszFile,
                   GENERIC_READ | GENERIC_WRITE,
                   (DWORD) 0,
                   (LPSECURITY_ATTRIBUTES) NULL,
                   CREATE_ALWAYS,
                   FILE_ATTRIBUTE_NORMAL,
                   (HANDLE) NULL);
 
    if (hf == INVALID_HANDLE_VALUE)
        errhandler("CreateFile", hwnd);
 
    hdr.bfType = 0x4d42;        /* 0x42 = "B" 0x4d = "M" */
 
    /* Compute the size of the entire file. */
 
    hdr.bfSize = (DWORD) (sizeof(BITMAPFILEHEADER) +
                 pbih->biSize + pbih->biClrUsed
                 * sizeof(RGBQUAD) + pbih->biSizeImage);
 
    hdr.bfReserved1 = 0;
    hdr.bfReserved2 = 0;
 
    /* Compute the offset to the array of color indices. */
 
    hdr.bfOffBits = (DWORD) sizeof(BITMAPFILEHEADER) +
                    pbih->biSize + pbih->biClrUsed
                    * sizeof (RGBQUAD);
 
    /* Copy the BITMAPFILEHEADER into the .BMP file. */
 
    if (!WriteFile(hf, (LPVOID) &hdr, sizeof(BITMAPFILEHEADER),
       (LPDWORD) &dwTmp, (LPOVERLAPPED) NULL))
       errhandler("WriteFile", hwnd);
 
    /* Copy the BITMAPINFOHEADER and RGBQUAD array into the file. */
 
    if (!WriteFile(hf, (LPVOID) pbih, sizeof(BITMAPINFOHEADER)
                  + pbih->biClrUsed * sizeof (RGBQUAD),
                  (LPDWORD) &dwTmp, (LPOVERLAPPED) NULL))
       errhandler("WriteFile", hwnd);
 
    /* Copy the array of color indices into the .BMP file. */
 
    dwTotal = cb = pbih->biSizeImage;
    hp = lpBits;
    while (cb > MAXWRITE)  {
            if (!WriteFile(hf, (LPSTR) hp, (int) MAXWRITE,
                          (LPDWORD) &dwTmp, (LPOVERLAPPED) NULL))
                errhandler("WriteFile", hwnd);
            cb-= MAXWRITE;
            hp += MAXWRITE;
    }
    if (!WriteFile(hf, (LPSTR) hp, (int) cb,
         (LPDWORD) &dwTmp, (LPOVERLAPPED) NULL))
           errhandler("WriteFile", hwnd);
 
    /* Close the .BMP file. */
 
    if (!CloseHandle(hf))
           errhandler("CloseHandle", hwnd);
 
    /* Free memory. */    GlobalFree((HGLOBAL)lpBits);
}
 

0

Featured Post

Free Tool: Port Scanner

Check which ports are open to the outside world. Helps make sure that your firewall rules are working as intended.

One of a set of tools we are providing to everyone as a way of saying thank you for being a part of the community.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Introduction: The undo support, implementing a stack. Continuing from the eigth article about sudoku.   We need a mechanism to keep track of the digits entered so as to implement an undo mechanism.  This should be a ‘Last In First Out’ collec…
Introduction: Dialogs (2) modeless dialog and a worker thread.  Handling data shared between threads.  Recursive functions. Continuing from the tenth article about sudoku.   Last article we worked with a modal dialog to help maintain informat…
This video will show you how to get GIT to work in Eclipse.   It will walk you through how to install the EGit plugin in eclipse and how to checkout an existing repository.
In response to a need for security and privacy, and to continue fostering an environment members can turn to for support, solutions, and education, Experts Exchange has created anonymous question capabilities. This new feature is available to our Pr…
Suggested Courses

589 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question