2.6.6.8 imgUnsharpmask

1 Menu Information
2 Brief Information
3 Command Line Usage
4 X-Function Execution Options
5 Variables
6 Description
7 Examples
8 Algorithm
9 References
10 Related X-Functions

Menu Information

Unsharp Mask

Brief Information

Apply unsharp mask to image

Command Line Usage

1. imgUnsharpmask a:=40;
2. imgUnsharpmask a:=20 r:=3 t:=3 option:=yuv img:=mat(1) oimg:=mat(2);

X-Function Execution Options

Please refer to the page for additional option switches when accessing the x-function from script

Variables

Display Name	Variable Name	I/O and Type	Default Value	Description
Adjust	a	Input int	0	Specifies the adjustment factor, which is a percentage. The range is from 0 to 500.
Neighborhood	r	Input int	1	Specifies the size of the neighborhood used for detecting edges. The range is from 0 to 1000.
Threshold	t	Input int	0	Specifies the threshold for determining the edges. If the difference between a pixel and its neighborhood is greater than this threshold, this pixel will be considered an edge pixel and will be sharpened. Valid range of this variable is from 0 to 255.
Color	option	Input int	rgb	Specifies the color space in which to apply the unsharp mask. Option list rgb:RGB_Space Uses the RGB space. yuv:YUV_Space Uses the YUV space. Generally, computation is faster than using RGB space.
Input Matrix	img	Input Image	<active>	Specifies the source image to be manipulated. The default input is the active image.
Output Image	oimg	Output Image	<input>	Specifies the output image. By default, the output image is the same as the input image. See the syntax here.

Description

This X-Function can be used to remove the blurring from the input image. It identifies pixels that are different from neighboring pixels and increases their contrast. This function can be viewed as a sharpening function. The edges and details in the output image are emphasized and have an enhanced appearance.

Examples

Code Sample

//Create a new folder in the Project Explorer
pe_mkdir Conversion path:=aa$;
pe_cd aa$;
//Create a matrix and import a sample image
window -t m;
path$ = System.path.program$;
fname$ = path$ + "samples\Image Processing and Analysis\leaves.jpg";
impimage;
window -r %h Original;
window -d;	//Duplicate the image
window -r %h BlueLeave;

imgC2gray;	//Convert to gray
window -d;	//Duplicate the image
imgUnsharpmask a:=80 r:=30; //Strenghen details

window -s T;	//Tile the windows horizontally

Algorithm

The computation uses L_UnsharpMaskBitmap() function from LEADTOOLS Main API. Please refer to the LEADTOOLS Main API Help file, Version 14 and read the L_UnsharpMaskBitmap topic.