L_InitBitmap (original) (raw)
Summary
Initializes the fields in a bitmap handle.
Syntax
#include "l_bitmap.h"
L_LTKRN_API L_INT L_InitBitmap(pBitmap, uStructSize, nWidth, nHeight, nBitsPerPixel)
Parameters
pBITMAPHANDLE pBitmap
Pointer to the bitmap handle to initialize.
L_UINT uStructSize
Size in bytes, of the structure pointed to by pBitmap, for versioning. Use sizeof(BITMAPHANDLE).
L_INT nWidth
Width of the image in pixels.
L_INT nHeight
Height of the image in pixels.
L_INT nBitsPerPixel
Number of bits per pixel in the image. Valid values are:
| Value | Meaning |
|---|---|
| 1 | For a 1-bit image. |
| 2 | For a 2-bit image. |
| 3 | For a 3-bit image. |
| 4 | For a 4-bit image. |
| 5 | For a 5-bit image. |
| 6 | For a 6-bit image. |
| 7 | For a 7-bit image. |
| 8 | For an 8-bit image. |
| 12 | For a 12-bit image. |
| 16 | For a 16-bit image. |
| 24 | For a 24-bit image. |
| 32 | For a 32-bit image. |
| 48 | For a 48-bit image. |
| 64 | For a 64-bit image. |
Returns
| Value | Meaning |
|---|---|
| SUCCESS | The function was successful. |
| < 1 | An error occurred. Refer to Return Codes. |
Comments
Support for 12 and 16-bit grayscale images is only available in the Document and Medical Imaging toolkits.
This is a low-level function that is necessary only if you need to initialize the bitmap handle and allocate memory in separate steps when creating a bitmap from scratch. L_CreateBitmap is usually a better choice.
This function must be called before using L_AllocateBitmap. This function only initializes the fields in the bitmap handle; it does not allocate any memory. If all zeroes are passed as the nWidth, nHeight, and nBitsPerPixel into this function, then all fields in the bitmap handle will be set to 0. Otherwise, all fields will be set to zero except the fields listed below.
When this function is called, the following fields will be set:
| Field | Value |
|---|---|
| Order | ORDER_RGB if you specify 8 bits per pixel or less; ORDER_GRAY for 12 or 16-bit grayscale; ORDER_BGR otherwise. ORDER_GRAY is valid only for 12 and 16-bit grayscale images and is only available in the Document and Medical Imaging toolkits. Please note that a 16-bpp image may be color or grayscale. If you are working with a 16-bit grayscale image, explicitly set BITMAPHANDLE.Order to ORDER_GRAY. By default, the order for a 16-bit image will be set to ORDER_BGR. |
| DitherMethod | Set by the L_DefaultDithering function |
| ViewPerspective | BOTTOM_LEFT [2] |
| Width | As passed into the function |
| Height | As passed into the function |
| BytesPerLine | Calculated using the specified width and bits per pixel, rounded on a 4-byte boundary |
| XResolution | 150 |
| YResolution | 150 |
Platforms
Win32, x64, Linux.
Required DLLs and Libraries
- LTKRN
- For a listing of the exact DLLs and Libraries needed, based on the toolkit version, refer to Files To Be Included With Your Application.
See Also
Functions
Topics
Example
For an example, refer to L_ResizeBitmap.
For complete sample code, refer to the RESIZE
example.