Saving .bmp file using hBitmap = CreateDIBSection() in C Win32 [duplicate]

Question

I have the following code. I want to use this information to create one .bmp file that shows the data from memory which is a image copied from a framegrabber into main memory, can somebody please let me? Thank you

LPSTR CreateBMP( HWND hAppWnd, int nImageType )

{
void * pWinGBits = NULL; int i; Z_BITMAPINFO zWinGHeader; // bitmapinfo for cerating the DIB

//  create DC for bitmap.
hDCBits = CreateCompatibleDC( ghDCMain );

switch ( nImageType )
{
    case bayer_filter:
    zWinGHeader.bmiHeader.biSize            = sizeof( BITMAPINFOHEADER );
    zWinGHeader.bmiHeader.biPlanes          = 1;
    zWinGHeader.bmiHeader.biClrImportant    = 0;
    zWinGHeader.bmiHeader.biHeight          = -lYSize;
    zWinGHeader.bmiHeader.biWidth           = lXSize;
    zWinGHeader.bmiHeader.biBitCount        = 32;
    zWinGHeader.bmiHeader.biClrUsed         = 0;//3;
    zWinGHeader.bmiHeader.biCompression     = BI_BITFIELDS;
    zWinGHeader.bmiHeader.biSizeImage       = 0;
    zWinGHeader.bmiColors[0].rgbBlue        = 0x00;
    zWinGHeader.bmiColors[0].rgbGreen       = 0x00;
    zWinGHeader.bmiColors[0].rgbRed         = 0xFF;
    zWinGHeader.bmiColors[0].rgbReserved    = 0x00;

    zWinGHeader.bmiColors[1].rgbBlue        = 0x00;
    zWinGHeader.bmiColors[1].rgbGreen       = 0xFF;
    zWinGHeader.bmiColors[1].rgbRed         = 0x00;
    zWinGHeader.bmiColors[1].rgbReserved    = 0x00;

    zWinGHeader.bmiColors[2].rgbBlue        = 0xFF;
    zWinGHeader.bmiColors[2].rgbGreen       = 0x00;
    zWinGHeader.bmiColors[2].rgbRed         = 0x00;
    zWinGHeader.bmiColors[2].rgbReserved    = 0x00;
    break;

    case color32:
    zWinGHeader.bmiHeader.biSize            = sizeof( BITMAPINFOHEADER );
    zWinGHeader.bmiHeader.biPlanes          = 1;
    zWinGHeader.bmiHeader.biClrImportant    = 0;
    zWinGHeader.bmiHeader.biHeight          = -lYSize;
    zWinGHeader.bmiHeader.biWidth           = lXSize/4;
    zWinGHeader.bmiHeader.biBitCount        = 32;
    zWinGHeader.bmiHeader.biClrUsed         = 0;
    zWinGHeader.bmiHeader.biCompression     = BI_BITFIELDS;
    zWinGHeader.bmiHeader.biSizeImage       = 0;
    zWinGHeader.bmiColors[0].rgbBlue        = 0x00;
    zWinGHeader.bmiColors[0].rgbGreen       = 0x00;
    zWinGHeader.bmiColors[0].rgbRed         = 0xFF;
    zWinGHeader.bmiColors[0].rgbReserved    = 0x00;

    zWinGHeader.bmiColors[1].rgbBlue        = 0x00;
    zWinGHeader.bmiColors[1].rgbGreen       = 0xFF;
    zWinGHeader.bmiColors[1].rgbRed         = 0x00;
    zWinGHeader.bmiColors[1].rgbReserved    = 0x00;

    zWinGHeader.bmiColors[2].rgbBlue        = 0xFF;
    zWinGHeader.bmiColors[2].rgbGreen       = 0x00;
    zWinGHeader.bmiColors[2].rgbRed         = 0x00;
    zWinGHeader.bmiColors[2].rgbReserved    = 0x00;
    break;

    case color24:
    zWinGHeader.bmiHeader.biSize            = sizeof( BITMAPINFOHEADER );
    zWinGHeader.bmiHeader.biPlanes          = 1;
    zWinGHeader.bmiHeader.biClrImportant    = 0;
    zWinGHeader.bmiHeader.biHeight          = -lYSize;
    zWinGHeader.bmiHeader.biWidth           = lXSize/3;
    zWinGHeader.bmiHeader.biBitCount        = 24;
    zWinGHeader.bmiHeader.biClrUsed         = 0;
    zWinGHeader.bmiHeader.biCompression     = BI_RGB;
    zWinGHeader.bmiHeader.biSizeImage       = 0;
    break;

    case color3x16:
    zWinGHeader.bmiHeader.biSize            = sizeof( BITMAPINFOHEADER );
    zWinGHeader.bmiHeader.biPlanes          = 1;
    zWinGHeader.bmiHeader.biClrImportant    = 0;
    zWinGHeader.bmiHeader.biHeight          = -lYSize;
    zWinGHeader.bmiHeader.biWidth           = lXSize/6;
    zWinGHeader.bmiHeader.biBitCount        = 32;
    zWinGHeader.bmiHeader.biClrUsed         = 0;
    zWinGHeader.bmiHeader.biCompression     = BI_BITFIELDS;
    zWinGHeader.bmiHeader.biSizeImage       = 0;
    zWinGHeader.bmiColors[0].rgbBlue        = 0x00;
    zWinGHeader.bmiColors[0].rgbGreen       = 0x00;
    zWinGHeader.bmiColors[0].rgbRed         = 0xFF;
    zWinGHeader.bmiColors[0].rgbReserved    = 0x00;

    zWinGHeader.bmiColors[1].rgbBlue        = 0x00;
    zWinGHeader.bmiColors[1].rgbGreen       = 0xFF;
    zWinGHeader.bmiColors[1].rgbRed         = 0x00;
    zWinGHeader.bmiColors[1].rgbReserved    = 0x00;

    zWinGHeader.bmiColors[2].rgbBlue        = 0xFF;
    zWinGHeader.bmiColors[2].rgbGreen       = 0x00;
    zWinGHeader.bmiColors[2].rgbRed         = 0x00;
    zWinGHeader.bmiColors[2].rgbReserved    = 0x00;
    break;

    case bw1x10:
    //  create bitmap-infoheader.
    zWinGHeader.bmiHeader.biSize        = sizeof( BITMAPINFOHEADER );
    zWinGHeader.bmiHeader.biPlanes      = 1;
    zWinGHeader.bmiHeader.biBitCount    = 8;
    zWinGHeader.bmiHeader.biCompression = BI_RGB;
    zWinGHeader.bmiHeader.biSizeImage   = 0;
    zWinGHeader.bmiHeader.biClrUsed     = 256;
    zWinGHeader.bmiHeader.biClrImportant= 0;
    zWinGHeader.bmiHeader.biHeight      = -lYSize;
    zWinGHeader.bmiHeader.biWidth       = lXSize/2;

    //  create colortable fot bitmap (grayvalues).
    for (i = 0; i < 256; i++) 
    {
        zWinGHeader.bmiColors[i].rgbGreen   = i;
        zWinGHeader.bmiColors[i].rgbBlue    = i;
        zWinGHeader.bmiColors[i].rgbRed     = i;

        zWinGHeader.bmiColors[i].rgbReserved = 0;
    }
    break;

    default:
    case bw8:
    //  create bitmap-infoheader.
    zWinGHeader.bmiHeader.biSize        = sizeof( BITMAPINFOHEADER );
    zWinGHeader.bmiHeader.biPlanes      = 1;
    zWinGHeader.bmiHeader.biBitCount    = 8;
    zWinGHeader.bmiHeader.biCompression = BI_RGB;
    zWinGHeader.bmiHeader.biSizeImage   = 0;
    zWinGHeader.bmiHeader.biClrUsed     = 256;
    zWinGHeader.bmiHeader.biClrImportant= 0;
    zWinGHeader.bmiHeader.biHeight      = -lYSize;
    zWinGHeader.bmiHeader.biWidth       = lXSize;

    //  create colortable fot bitmap (grayvalues).
    for (i = 0; i < 256; i++) 
    {
        zWinGHeader.bmiColors[i].rgbGreen   = i;
        zWinGHeader.bmiColors[i].rgbBlue    = i;
        zWinGHeader.bmiColors[i].rgbRed     = i;

        zWinGHeader.bmiColors[i].rgbReserved = 0;
    }
    break;
}

//  cerate identity palette 
hPal = CreateIdentityPalette( zWinGHeader.bmiColors );

//  get new palette into DC and map into physical palette register.
hOldPal = SelectPalette( ghDCMain, hPal, FALSE);
RealizePalette( ghDCMain );

//  cerate DIB-Section f黵 direct access of image-data.
hBitmap = CreateDIBSection(
    hDCBits,                        //  handle of device context
    (BITMAPINFO *)&zWinGHeader,     //  address of structure containing
                                    //  bitmap size, format and color data
    DIB_RGB_COLORS,                 //  color data type indicator: RGB values
                                    //  or palette indices
    &pWinGBits,                     //  pointer to variable to receive a pointer
                                    //  to the bitmap's bit values
    NULL,                           //  optional handle to a file mapping object
    0                               //  offset to the bitmap bit values within
                                    //  the file mapping object
);  
//  get bitmap into DC .
hOldBitmap = (HBITMAP)SelectObject( hDCBits, hBitmap );
return pWinGBits;           //  return pointer to DIB 

}

Micronesian

Answer 1

The easiest way to go from image data in memory or an HBITMAP to an image file using the win32 api is with GDI+. Just create a Bitmap object from your image data or HBITMAP (see http://msdn.microsoft.com/en-us/library/ms536314%28v=vs.85%29.aspx), then use the Save method to create the file (see http://msdn.microsoft.com/en-us/library/ms535407%28v=vs.85%29.aspx). If you're not able to use C++, those methods also exist as functions callable from C.

Nihhi

as I am using C program, I cant use GDI+ to the project. also the GDIFlat didnt work as well :( – Micronesian

Answer 2

In C, the conversion is a huge pain since you need to build the bitmap manually. Here is code that I used in the past that did that:

PBITMAPINFO CreateBitmapInfoStruct(HBITMAP hBmp)
{ 
 BITMAP bmp; 
 PBITMAPINFO pbmi; 
 WORD    cClrBits;
 // Retrieve the bitmap color format, width, and height. 
 if (!GetObject(hBmp, sizeof(BITMAP), (LPSTR)&bmp)) 
 return NULL;

 // 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) * (1<< 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 = (1<<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. 
 // For Windows NT, the width must be DWORD aligned unless 
 // the bitmap is RLE compressed. This example shows this. 
 // For Windows 95/98/Me, the width must be WORD aligned unless the 
 // bitmap is RLE compressed.
 pbmi->bmiHeader.biSizeImage = ((pbmi->bmiHeader.biWidth * cClrBits +31) &amp; ~31) /8
 * pbmi->bmiHeader.biHeight; 
 // Set biClrImportant to 0, indicating that all of the 
 // device colors are important. 
 pbmi->bmiHeader.biClrImportant = 0; 
 return pbmi; 
} 

void CreateBMPFile(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) 
 return; 

 // 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)) 
 {
 return;
 }

 // Create the .BMP file. 
 hf = CreateFile(pszFile, 
 GENERIC_READ | GENERIC_WRITE, 
 (DWORD) 0, 
 NULL, 
 CREATE_ALWAYS, 
 FILE_ATTRIBUTE_NORMAL, 
 (HANDLE) NULL); 
 if (hf == INVALID_HANDLE_VALUE) 
 return; 
 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) &amp;hdr, sizeof(BITMAPFILEHEADER), 
 (LPDWORD) &amp;dwTmp,  NULL)) 
 {
 return; 
 }

 // Copy the BITMAPINFOHEADER and RGBQUAD array into the file. 
 if (!WriteFile(hf, (LPVOID) pbih, sizeof(BITMAPINFOHEADER) 
 + pbih->biClrUsed * sizeof (RGBQUAD), 
 (LPDWORD) &amp;dwTmp, ( NULL))) 
 return; 

 // Copy the array of color indices into the .BMP file. 
 dwTotal = cb = pbih->biSizeImage; 
 hp = lpBits; 
 if (!WriteFile(hf, (LPSTR) hp, (int) cb, (LPDWORD) &amp;dwTmp,NULL)) 
 return; 

 // Close the .BMP file. 
 if (!CloseHandle(hf)) 
 return; 

 // Free memory. 
 GlobalFree((HGLOBAL)lpBits);
}


//code for saving bitmap
HBITMAP hBitmap;
HDC hdc;
...
PBITMAPINFO pBitmapInfo = CreateBitmapInfoStruct(hBitmap);
CreateBMPFile(_T("c:\\temp\\picture.bmp"), pBitmapInfo, hBitmap, hdc);

If you are allowed to use C++, you can do this a lot easier (in a few lines) using CImage from ATL.

Averil

hi there I did add your code, it create the file, but it doesnt show anytihng !!! do you have any idea why? – Micronesian

You have an empty bitmap there because you did not populate it yet. All you did was create the bitmap object. What are you expecting to see/trying to achieve? – Averil

I have a framegrabber and a camera, which I am able to show a live the images, but I want to save one frame into a .bmp file. but in any way I am attemping to save this .bmp file it doesnt show me anytihng. can you please explain how can I save the data into a .bmp file inorder to show me the image on the file ? – Micronesian

As I said, the bitmap you created needs to be populated with contents. Since you are copying from one place to another, maybe you should take a look at BitBlt. In what form do you get the image from the framegrabber? – Averil

the image is a 8bit (gray) image, which can be stored in the main memory of the computer by mvfg_getbufptr() function, which return a pointer to the address on the first image in the memory – Micronesian

Your problem is not converting a HBITMAP to a .bmp file then. It is how to transfer the buffer returned to you from that subject to a HBITMAP. Unfortunately that is too specific for me to help you on since I have no experience with the library defining mvfg_getbufptr(). – Averil

@MikeKwan Where can I get the hdc to save the bitmap? – Byelaw

Answer 3

The CreateDIBSection function creates a DIB* that applications can write to directly. The function gives you a pointer to the location of the bitmap bit values.

This call does not create a bitmap image, why do you want to use that function?

• Device Independent Bitmap

Hooch

well, I have a framegrabber and a camera, and have been trying different solution to save the images from a part of memory to a .bmp file, it in everysolution it created thje images but it doesnt show anytihng, do you have any idea why ? – Micronesian