CreateDIBSection function (wingdi.h)
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. You can supply a handle to a file-mapping object that the function will use to create the bitmap, or you can let the system allocate the memory for the bitmap.
Syntax
HBITMAP CreateDIBSection(
[in] HDC hdc,
[in] const BITMAPINFO *pbmi,
[in] UINT usage,
[out] VOID **ppvBits,
[in] HANDLE hSection,
[in] DWORD offset
);
Parameters
[in] hdc
A handle to a device context. If the value of iUsage is DIB_PAL_COLORS, the function uses this device context's logical palette to initialize the DIB colors.
[in] pbmi
A pointer to a BITMAPINFO structure that specifies various attributes of the DIB, including the bitmap dimensions and colors.
[in] usage
The type of data contained in the bmiColors array member of the BITMAPINFO structure pointed to by pbmi (either logical palette indexes or literal RGB values). The following values are defined.
| Value | Meaning |
|---|---|
|
The bmiColors member is an array of 16-bit indexes into the logical palette of the device context specified by hdc. |
|
The BITMAPINFO structure contains an array of literal RGB values. |
[out] ppvBits
A pointer to a variable that receives a pointer to the location of the DIB bit values.
[in] hSection
A handle to a file-mapping object that the function will use to create the DIB. This parameter can be NULL.
If hSection is not NULL, it must be a handle to a file-mapping object created by calling the CreateFileMapping function with the PAGE_READWRITE or PAGE_WRITECOPY flag. Read-only DIB sections are not supported. Handles created by other means will cause CreateDIBSection to fail.
If hSection is not NULL, the CreateDIBSection function locates the bitmap bit values at offset dwOffset in the file-mapping object referred to by hSection. An application can later retrieve the hSection handle by calling the GetObject function with the HBITMAP returned by CreateDIBSection.
If hSection is NULL, the system allocates memory for the DIB. In this case, the CreateDIBSection function ignores the dwOffset parameter. An application cannot later obtain a handle to this memory. The dshSection member of the DIBSECTION structure filled in by calling the GetObject function will be NULL.
[in] offset
The offset from the beginning of the file-mapping object referenced by hSection where storage for the bitmap bit values is to begin. This value is ignored if hSection is NULL. The bitmap bit values are aligned on doubleword boundaries, so dwOffset must be a multiple of the size of a DWORD.
Return value
If the function succeeds, the return value is a handle to the newly created DIB, and *ppvBits points to the bitmap bit values.
If the function fails, the return value is NULL, and *ppvBits is NULL. To get extended error information, call GetLastError.
GetLastError can return the following value:
| Error code | Description |
|---|---|
|
One or more of the input parameters is invalid. |
Remarks
As noted above, if hSection is NULL, the system allocates memory for the DIB. The system closes the handle to that memory when you later delete the DIB by calling the DeleteObject function. If hSection is not NULL, you must close the hSection memory handle yourself after calling DeleteObject to delete the bitmap.
You cannot paste a DIB section from one application into another application.
CreateDIBSection does not use the BITMAPINFOHEADER parameters biXPelsPerMeter or biYPelsPerMeter and will not provide resolution information in the BITMAPINFO structure.
You need to guarantee that the GDI subsystem has completed any drawing to a bitmap created by CreateDIBSection before you draw to the bitmap yourself. Access to the bitmap must be synchronized. Do this by calling the GdiFlush function. This applies to any use of the pointer to the bitmap bit values, including passing the pointer in calls to functions such as SetDIBits.
ICM: No color management is done.
Requirements
| Requirement | Value |
|---|---|
| Minimum supported client | Windows 2000 Professional [desktop apps only] |
| Minimum supported server | Windows 2000 Server [desktop apps only] |
| Target Platform | Windows |
| Header | wingdi.h (include Windows.h) |
| Library | Gdi32.lib |
| DLL | Gdi32.dll |