CannyEdgeDetector

Documentation of 'Catalano.Imaging.Filters.CannyEdgeDetector' Java class CannyEdgeDetector

All Classes

Summary:
Nested |
Field |
Constr |
Method

Detail:
Field |
Constr |
Method

java.lang.Object
- Catalano.Imaging.Filters.CannyEdgeDetector

All Implemented Interfaces:

IApplyInPlace
```
public class CannyEdgeDetector
extends java.lang.Object
implements IApplyInPlace
```
Canny edge detector. The filter searches for objects' edges by applying Canny edge detector. The implementation follows Bill Green's Canny edge detection tutorial.
The implemented canny edge detector has one difference with the above linked algorithm. The difference is in hysteresis step, which is a bit simplified (getting faster as a result). On the hysteresis step each pixel is compared with two threshold values: HighThreshold and LowThreshold. If pixel's value is greater or equal to HighThreshold, then it is kept as edge pixel. If pixel's value is greater or equal to LowThreshold, then it is kept as edge pixel only if there is at least one neighbouring pixel (8 neighbours are checked) which has value greater or equal to HighThreshold; otherwise it is none edge pixel. In the case if pixel's value is less than LowThreshold, then it is marked as none edge immediately.
Supported types: Grayscale.
Coordinate System: Matrix.

Constructor Summary

Constructors
Constructor and Description
`CannyEdgeDetector()` Initialize a new instance of the CannyEdgeDetector class.
`CannyEdgeDetector(int lowThreshold, int highThreshold)` Initialize a new instance of the CannyEdgeDetector class.
`CannyEdgeDetector(int lowThreshold, int highThreshold, double sigma)` Initialize a new instance of the CannyEdgeDetector class.
`CannyEdgeDetector(int lowThreshold, int highThreshold, double sigma, int size)` Initialize a new instance of the CannyEdgeDetector class.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`applyInPlace(FastBitmap fastBitmap)` Apply filter to an image.
`int`	`getHighThreshold()` Get High threshold.
`int`	`getLowThreshold()` Get Low threshold.
`double`	`getSigma()` Get Gaussian sigma.
`int`	`getSize()` Get Gaussian kernel size.
`void`	`setHighThreshold(int highThreshold)` Set High threshold.
`void`	`setLowThreshold(int lowThreshold)` Set Low threshold.
`void`	`setSigma(double sigma)` Set Gaussian sigma.
`void`	`setSize(int size)` Set Gaussian kernel size.

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

- Constructor Detail
  - CannyEdgeDetector
```
public CannyEdgeDetector()
```
    Initialize a new instance of the CannyEdgeDetector class.
  - CannyEdgeDetector
```
public CannyEdgeDetector(int lowThreshold,
                         int highThreshold)
```
    Initialize a new instance of the CannyEdgeDetector class.
    
    Parameters:
    
    lowThreshold - Low threshold. (Used for hysteresis).
    
    highThreshold - High Threshold. (Used for hysteresis).
  - CannyEdgeDetector
```
public CannyEdgeDetector(int lowThreshold,
                         int highThreshold,
                         double sigma)
```
    Initialize a new instance of the CannyEdgeDetector class.
    
    Parameters:
    
    lowThreshold - Low threshold. (Used for hysteresis).
    
    highThreshold - High Threshold. (Used for hysteresis).
    
    sigma - Gaussian sigma.
  - CannyEdgeDetector
```
public CannyEdgeDetector(int lowThreshold,
                         int highThreshold,
                         double sigma,
                         int size)
```
    Initialize a new instance of the CannyEdgeDetector class.
    
    Parameters:
    
    lowThreshold - Low threshold. (Used for hysteresis).
    
    highThreshold - High Threshold. (Used for hysteresis).
    
    sigma - Gaussian sigma.
    
    size - Size of gaussian kernel.
- Method Detail
  - getLowThreshold
```
public int getLowThreshold()
```
    Get Low threshold. Used for Hysteresis.
    
    Returns:
    
    Low threshold.
  - setLowThreshold
```
public void setLowThreshold(int lowThreshold)
```
    Set Low threshold.
    
    Parameters:
    
    lowThreshold - Threshold value.
  - getHighThreshold
```
public int getHighThreshold()
```
    Get High threshold. Used for Hysteresis.
    
    Returns:
    
    Threshold value.
  - setHighThreshold
```
public void setHighThreshold(int highThreshold)
```
    Set High threshold.
    
    Parameters:
    
    highThreshold - Threshold value.
  - getSigma
```
public double getSigma()
```
    Get Gaussian sigma.
    
    Returns:
    
    Gaussian sigma.
  - setSigma
```
public void setSigma(double sigma)
```
    Set Gaussian sigma.
    
    Parameters:
    
    sigma - Gaussian sigma.
  - getSize
```
public int getSize()
```
    Get Gaussian kernel size.
    
    Returns:
    
    Gaussian kernel size.
  - setSize
```
public void setSize(int size)
```
    Set Gaussian kernel size.
    
    Parameters:
    
    size - Gaussian kernel size.
  - applyInPlace
```
public void applyInPlace(FastBitmap fastBitmap)
```
    Description copied from interface: IApplyInPlace
    
    Apply filter to an image.
    
    Specified by:
    
    applyInPlace in interface IApplyInPlace
    
    Parameters:
    
    fastBitmap - Image to be processed.

Class CannyEdgeDetector

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

CannyEdgeDetector

CannyEdgeDetector

CannyEdgeDetector

CannyEdgeDetector

Method Detail

getLowThreshold

setLowThreshold

getHighThreshold

setHighThreshold

getSigma

setSigma

getSize

setSize

applyInPlace