I get this code from MSDN and make a few changes.
(HBITMAP to bmp)
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) & ~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)&hdr, sizeof(BITMAPFILEHEADER), (LPDWORD)&dwTmp, NULL)) { return; } // Copy the BITMAPINFOHEADER and RGBQUAD array into the file. if (!WriteFile(hf, (LPVOID)pbih, sizeof(BITMAPINFOHEADER) + pbih->biClrUsed * sizeof(RGBQUAD), (LPDWORD)&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)&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);
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