GradientCalculator (DMLab Library API for 0.0.4-SNAPSHOT)

java.lang.Object
- edu.gsu.cs.dmlab.imageproc.edgedetection.GradientCalculator

All Implemented Interfaces:

IGradientCalculator
```
public class GradientCalculator
extends Object
implements IGradientCalculator
```
A class for calculating the gradient of pixel intensities on source images. This class uses different kernels, depending on the provided gradient operator name, and calculated both horizontal and vertical derivatives, as well as the magnitude and angle of changes in the color intensity of pixels.
Pass the string "prewitt" to its constructor to apply Prewitt operator or "sobel" to apply Sobel operator.
There exists other operators which have not been yet implemented in this class:
Roberts operator
Laplacian operator

Author:: Azim Ahmadzadeh, updated by Dustin Kempton, Data Mining Lab, Georgia State University

Constructor Summary

Constructors
Constructor Description

GradientCalculator(String gradientName)
This constructor sets the gradient operator based on the given name.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`Gradient`	`calculateGradientCart(double[][] image)`	Calculates the gradient of pixel intensities on the input image and returns the results in the original Cartesian coordinate system.
`Gradient`	`calculateGradientPolar(double[][] image)`	Calculates the gradient of pixel intensities on the input image and returns the results in a Polar coordinate system

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - GradientCalculator
```
public GradientCalculator(String gradientName)
```
    This constructor sets the gradient operator based on the given name.
    
    Parameters:
    
    gradientName - name of the gradient operator among the following options:
    "prewitt": Prewitt operator
    "sobel": Sobel operator
- Method Detail
  - calculateGradientPolar
```
public Gradient calculateGradientPolar(double[][] image)
```
    Description copied from interface: IGradientCalculator
    
    Calculates the gradient of pixel intensities on the input image and returns the results in a Polar coordinate system
    
    Specified by:
    
    calculateGradientPolar in interface IGradientCalculator
    
    Parameters:
    
    image - The input image in the form of a 2D array of doubles
    
    Returns:
    
    The gradient as gx=theta and gy=r
    The range of theta is (-3.14, +3.14)
  - calculateGradientCart
```
public Gradient calculateGradientCart(double[][] image)
```
    Description copied from interface: IGradientCalculator
    
    Calculates the gradient of pixel intensities on the input image and returns the results in the original Cartesian coordinate system.
    
    Specified by:
    
    calculateGradientCart in interface IGradientCalculator
    
    Parameters:
    
    image - The input image in the form of a 2D array of doubles
    
    Returns:
    
    The gradient in x and y direction