L_ApplyLinearVOILUT

#include "l_bitmap.h"

L_LTIMGCOR_API L_INT L_ApplyLinearVOILUT (pBitmap, fCenter, fWidth, uFlags)

pBITMAPHANDLE pBitmap;	pointer to the main bitmap handle
L_DOUBLE fCenter;	window center
L_DOUBLE fWidth;	window width
L_UINT uFlags;	flags

Sets up the paint or paint and image processing functions' window leveling options for a specific bitmap through a linear transformation described by window center and width.

Parameter	Description
pBitmap	Pointer to the bitmap handle referencing the bitmap to be leveled.
fCenter	Window Center for display.
fWidth	Window Width for display.
uFlags	Flags which determine the behavior of this function. Possible values are one or an OR-ed combination of the following:
	Value	Meaning
	VOI_LUT_UPDATE_MIN_MAX	[0x0001] If set, the function will recalculate pBitmap->MinVal based on the minimum intensity inside the bitmap and recalculate pBitmap->MaxVal based on the maximum intensity inside the bitmap.
	VOI_LUT_REVERSE_ORDER	[0x0002] If set, the function will fill the bitmap display LUT in reverse order (light to dark instead of dark to light).
	VOI_LUT_PAINT_ONLY	[0x0004] Set the LUT for paint only, not image processing. For more information, refer to BITMAPHANDLE.Flags.UseLUT.
	VOI_LUT_IGNORE_EXISTING_PALETTE	[0x0008] .

Returns

SUCCESS	The function was successful.
< 1	An error occurred. Refer to Return Codes.

Comments

This function sets up the paint or paint & image processing functions' window leveling options for a specific bitmap through a linear transformation described by window center and width. In the DICOM world, this is referred to as "applying a linear VOI LUT".

This function will remap the LUT used to display and process a bitmap by applying the linear transformation described by window center and window width. In the DICOM world this is referred to as applying a "linear VOI LUT". The DICOM standard states:

"Window Center and Window Width specify a linear conversion from stored pixel values (after any Modality LUT or Rescale Slope and Intercept specified in the IOD have been applied) to values to be displayed. Window Center contains the input value that is the center of the window. Window Width contains the width of the window." Please see "VOI LUT Module Attributes" in the DICOM standard for more details.

This function does not change the image data; it only updates the entries inside the bitmap LUT.

It is best to always set the VOI_LUT_UPDATE_MIN_MAX flag.

When working with DICOM files you will need to set VOI_LUT_REVERSE_ORDER flag if the photometric interpretation of the image is "MONOCHROME1". If an image is "MONOCHROME1", the minimum grayscale value is intended to be displayed as white after any VOI gray scale transformations have been performed.

This function supports 12 and 16-bit grayscale images. Support for 12 and 16-bit grayscale images is available in the Document and Medical Imaging toolkits.

This function does not support 32-bit grayscale images. It returns the error code ERROR_GRAY32_UNSUPPORTED if a 32-bit grayscale image is passed to this function.

The BITMAPHANDLE has some members in its structure that are intended for internal use, including pLUT, PaintHighBit and PaintLowBit that are useful when window-leveling. For more information about these members, used when displaying images or performing image processing, refer to BITMAPHANDLE LUT and its Uses. More information can be found in the LTKRN.H header file, which describes the entire structure.

Required DLLs and Libraries

LTIMGCOR

For a listing of the exact DLLs and Libraries needed, based on the toolkit version, refer to Files To Be Included With Your Application.

Platforms

Win32, x64, Linux.

Example

For an example, refer to L_ApplyVOILUT.

See Also

Dllsteps

BITMAPHANDLE LUT and its Uses

Help Version 19.0.2017.10.27

LEADTOOLS Raster Imaging C API Help

Introduction

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LEADTOOLS Raster Imaging Features

Redistributables/Files To Be Included With Your Application

Functions:	L_ApplyVOILUT, L_RemapBitmapIntensity, L_ApplyModalityLUT, L_ApplyLinearModalityLUT, L_DicomGetWindow, L_AdjustBitmapTint, L_GammaCorrectBitmapExt
Topics:	Raster Image Functions: Modifying Intensity Values
	Changing Brightness and Contrast
	Raster Image Functions: Changing Brightness and Contrast
	BITMAPHANDLE LUT and its Uses