Bitmap bits

[bankai123]

I've used the CreateDibSection function to create a DIB for bitmap... HWND hWnd = this->GetSafeHwnd(); HDC hdc = ::GetDC(hWnd); BITMAPINFO bmpInfo; ZeroMemory(&bmpInfo,sizeof(bmpInfo)); bmpInfo.bmiHeader.biSize = sizeof(BITMAPINFOHEADER); bmpInfo.bmiHeader.biBitCount = 8; bmpInfo.bmiHeader.biCompression = BI_RGB; bmpInfo.bmiHeader.biSizeImage = 0; // Set to 0 for BI_RGB images bmpInfo.bmiHeader.biPlanes = 1; bmpInfo.bmiHeader.biHeight = 768; bmpInfo.bmiHeader.biWidth = 1024; bmpInfo.bmiHeader.biClrUsed = 256; hFrameBitmap = CreateDIBSection(hFrameDC, &bmpInfo, DIB_RGB_COLORS, **&pBits**, NULL, NULL); I'm wondering how I can set the 4th parameter to point to a FILE* type which I store my raw pixel data, where pBits must be a LPVOID. Thanks

[Chris Losinger]

bankai123 wrote:

I'm wondering how I can set the 4th parameter to point to a FILE* type which I store my raw pixel data, where pBits must be a LPVOID.

you can't use a FILE*, but you can create a memory-mapped file, if you simply can't read that pixel data into memory:

// open the file
HANDLE hFile = CreateFile(pFileName,
GENERIC_READ,
FILE_SHARE_READ,
NULL,
OPEN_EXISTING,
FILE_ATTRIBUTE_NORMAL,
NULL);
// how big is it?
DWORD dwSize = GetFileSize(hFile, NULL);

// turn this file into virtual memory
HANDLE hCFM = CreateFileMapping(hFile, NULL, PAGE_READONLY, 0, 0, NULL);
LPVOID pData = MapViewOfFile(hCFM, FILE_MAP_READ, 0, 0, 0);

... and now pData is a pointer to the data in the file

// clean up the file system stuff
UnmapViewOfFile(pData);
CloseHandle(hFile);

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