de.unihalle.informatik.MiToBo.segmentation.thresholds

Class HysteresisThresholding

java.lang.Object

de.unihalle.informatik.Alida.operator.ALDOperator

de.unihalle.informatik.MiToBo.core.operator.MTBOperator

de.unihalle.informatik.MiToBo.segmentation.thresholds.HysteresisThresholding

All Implemented Interfaces:

de.unihalle.informatik.Alida.datatypes.ALDConfigurationValidator, de.unihalle.informatik.Alida.operator.events.ALDOperatorExecutionProgressEventListener, EventListener

@ALDAOperator(genericExecutionMode=ALL,
              level=APPLICATION)
public class HysteresisThresholding
extends MTBOperator

Hysteresis thresholding on gray-scale images.

This thresholding scheme applies two thresholds $t_{l}$ and $t_{h}$ to the image. All pixels having an intensity value equal or larger than $t_{h}$ are assigned to the foreground. In addition, also pixels with an intensity value equal or higher to the lower threshold are included in the foreground if they transitively link to a pixel with an intensity value equal or larger than $t_{h}$.

This thresholding heuristic is, e.g., used in the Canny edge detector.

Author:

moeller

Nested Class Summary

Nested classes/interfaces inherited from class de.unihalle.informatik.Alida.operator.ALDOperator

de.unihalle.informatik.Alida.operator.ALDOperator.HidingMode, de.unihalle.informatik.Alida.operator.ALDOperator.HistoryConstructionMode

Field Summary

Fields

Modifier and Type	Field and Description
protected MTBImage	inImg Image to process.
protected MTBImageByte	resultImage Resulting binarized image.
protected Double	threshHigh Upper threshold.
protected Double	threshLow Lower threshold.

Fields inherited from class de.unihalle.informatik.Alida.operator.ALDOperator

completeDAG, name, operatorExecutionEventlistenerList, portHashAccess, verbose, versionProvider

Constructor Summary

Constructors

Constructor and Description
HysteresisThresholding() Standard constructor.

Method Summary

Modifier and Type	Method and Description
MTBImageByte	getResultImage() Returns the result image.
protected static void	labelNeighbors(MTBImage img, MTBImage result, boolean[][] procMap, int x, int y, double tl, double th) Function for recursive labeling of foreground pixels.
protected void	operate()
void	setHigherThreshold(double d) Specify higher threshold.
void	setInputImage(MTBImage image) Set input image.
void	setLowerThreshold(double d) Specify lower threshold.

Methods inherited from class de.unihalle.informatik.MiToBo.core.operator.MTBOperator

readResolve

Methods inherited from class de.unihalle.informatik.Alida.operator.ALDOperator

addOperatorExecutionProgressEventListener, addParameter, addParameter, addParameterUnconditioned, fieldContained, fireOperatorExecutionProgressEvent, getALDPortHashAccessKey, getConstructionMode, getDocumentation, getHidingMode, getInactiveParameterNames, getInInoutNames, getInInoutNames, getInNames, getInOutNames, getMissingRequiredInputs, getName, getNumParameters, getOutInoutNames, getOutNames, getParameter, getParameterDescriptor, getParameterDescriptorUnconditioned, getParameterNames, getParameterUnconditioned, getSupplementalNames, getVerbose, getVersion, handleOperatorExecutionProgressEvent, hasInOutParameters, hasParameter, isAnnotatedParameter, isConfigured, print, print, print, printInterface, printInterface, readHistory, reinitializeParameterDescriptors, removeOperatorExecutionProgressEventListener, removeParameter, runOp, runOp, runOp, setConstructionMode, setConstructionMode, setConstructionMode, setHidingMode, setName, setParameter, setParameterUnconditioned, setVerbose, toStringVerbose, unconfiguredItems, validate, validateCustom, validateGeneric, writeHistory, writeHistory, writeHistory

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

inImg

@Parameter(label="Input Image",
           required=true,
           dataIOOrder=0,
           direction=IN,
           description="Input image.")
protected transient MTBImage inImg

Image to process.

threshHigh

@Parameter(label="Upper Threshold",
           required=true,
           dataIOOrder=1,
           direction=IN,
           description="Higher threshold.")
protected Double threshHigh

Upper threshold.

threshLow

@Parameter(label="Lower Threshold",
           required=true,
           dataIOOrder=2,
           direction=IN,
           description="Lower threshold.")
protected Double threshLow

Lower threshold.

resultImage

@Parameter(label="Thresholded Image",
           direction=OUT,
           description="Thresholded binary image.")
protected transient MTBImageByte resultImage

Resulting binarized image.

Constructor Detail

HysteresisThresholding

public HysteresisThresholding()
                       throws de.unihalle.informatik.Alida.exceptions.ALDOperatorException

Standard constructor. A new empty operator object is initialized.

Throws:

de.unihalle.informatik.Alida.exceptions.ALDOperatorException

Method Detail

operate

protected void operate()

Specified by:

operate in class de.unihalle.informatik.Alida.operator.ALDOperator

labelNeighbors

protected static void labelNeighbors(MTBImage img,
                                     MTBImage result,
                                     boolean[][] procMap,
                                     int x,
                                     int y,
                                     double tl,
                                     double th)

Function for recursive labeling of foreground pixels.

Refer to the hysteresis threshold algorithm for details.

Parameters:

img - Input image.

result - Binary result image.

procMap - Map to remember pixels already processed.

x - Current x-position.

y - Current y-position.

tl - Lower threshold.

th - Higher threshold.

setInputImage

public void setInputImage(MTBImage image)

Set input image.

Parameters:

image - Image to process.

setLowerThreshold

public void setLowerThreshold(double d)

Specify lower threshold.

Parameters:

d - Threshold value.

setHigherThreshold

public void setHigherThreshold(double d)

Specify higher threshold.

Parameters:

d - Threshold value.

getResultImage

public MTBImageByte getResultImage()

Returns the result image.

Returns:

Binary result image.