de.unihalle.informatik.MiToBo.segmentation.snakes.energies

Class MTBSnakeEnergyCDIB_Intensity

java.lang.Object

de.unihalle.informatik.MiToBo.segmentation.snakes.energies.MTBSnakeEnergyCDImageBased

de.unihalle.informatik.MiToBo.segmentation.snakes.energies.MTBSnakeEnergyCDIB_Intensity

All Implemented Interfaces:

MTBActiveContourEnergy, MTBActiveContourEnergyDerivable, MTBSnakeEnergyComputable, MTBSnakeEnergyDerivable

@ALDDerivedClass
 @ALDParametrizedClass
public class MTBSnakeEnergyCDIB_Intensity
extends MTBSnakeEnergyCDImageBased

External snake energy based on image intensities.

The energy for a snake C is defined as follows:

\begin{equation*} E(C) = \int_0^1 I(C(s)) ds \end{equation*}

Applying this energy a snake tends to move towards dark areas in an image, i.e. moves in the opposite direction of the local intensity gradient.

Note that this energy has only a small capture range of one or two pixels, thus, your initialization is required to be very accurate already.

Author:

Danny Misiak

Field Summary

Fields

Modifier and Type	Field and Description
private MTBImage	image The given input image to calculate the external energy from it.
private MTBImageDouble	imageNormalized Normalized version of input image used in calculations.

Fields inherited from class de.unihalle.informatik.MiToBo.segmentation.snakes.energies.MTBSnakeEnergyCDImageBased

height, normalizationFactor, normMode, scaleFactor, width

Fields inherited from interface de.unihalle.informatik.MiToBo.segmentation.snakes.energies.MTBSnakeEnergyDerivable

targetEnergyRange

Constructor Summary

Constructors

Constructor and Description
MTBSnakeEnergyCDIB_Intensity() Default constructor.
MTBSnakeEnergyCDIB_Intensity(MTBImage _image) Constructor to create a new SnakeExternalEnergyIntensity object.

Method Summary

Modifier and Type	Method and Description
Jama.Matrix	getDerivative_VectorPart(SnakeOptimizerSingleVarCalc opt) Returns the vector part of this energy for snake optimization.
double	getDerivativeX(double x, double y) Get x-derivative of external snake energy at given position using central differences.
double	getDerivativeY(double x, double y) Get y-derivative of external snake energy at given position using central differences.
double	getValue(double x, double y) Returns the value of the external energy at the given position.
boolean	initEnergy(SnakeOptimizerSingle o) Init routine which is called once before the energy is actually used.
void	normalizeEnergy() Normalize the external energy in a range [-1.0, 1.0].
String	toString() Get an identifier string for the energy object.

Methods inherited from class de.unihalle.informatik.MiToBo.segmentation.snakes.energies.MTBSnakeEnergyCDImageBased

calcEnergy, calcEnergy, getDerivative_MatrixPart, getDerivativeX_norm, getDerivativeY_norm, getScaleFactor, getValue_norm, requiresCounterClockwiseContourSorting, requiresOverlapMask, setScaleFactor, updateStatus

Methods inherited from class java.lang.Object

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

Field Detail

image

@ALDClassParameter(label="Input Image")
private MTBImage image

The given input image to calculate the external energy from it.

imageNormalized

private MTBImageDouble imageNormalized

Normalized version of input image used in calculations.

Constructor Detail

MTBSnakeEnergyCDIB_Intensity

public MTBSnakeEnergyCDIB_Intensity()

Default constructor.

MTBSnakeEnergyCDIB_Intensity

public MTBSnakeEnergyCDIB_Intensity(MTBImage _image)

Constructor to create a new SnakeExternalEnergyIntensity object.

Parameters:

_image - input image

Method Detail

initEnergy

public boolean initEnergy(SnakeOptimizerSingle o)

Description copied from interface: MTBSnakeEnergyDerivable

Init routine which is called once before the energy is actually used.

In this routine global parameter settings can be handled or other initialization stuff be done. The SnakeOptimizer will call this routine once before the actual use of the energy. If no stuff needs to be done in advance the routine should at least return true.

Specified by:

initEnergy in interface MTBSnakeEnergyComputable

Specified by:

initEnergy in interface MTBSnakeEnergyDerivable

Overrides:

initEnergy in class MTBSnakeEnergyCDImageBased

Parameters:

o - Calling snake optimizer.

Returns:

True if init was successful, otherwise false.

getValue

public double getValue(double x,
                       double y)

Returns the value of the external energy at the given position.

Specified by:

getValue in class MTBSnakeEnergyCDImageBased

Parameters:

x - x-coordinate of position

y - y-coordinate of position

Returns:

Absolute value of external energy.

getDerivative_VectorPart

public Jama.Matrix getDerivative_VectorPart(SnakeOptimizerSingleVarCalc opt)

Description copied from interface: MTBSnakeEnergyDerivable

Returns the vector part of this energy for snake optimization.

Specified by:

getDerivative_VectorPart in interface MTBSnakeEnergyDerivable

Overrides:

getDerivative_VectorPart in class MTBSnakeEnergyCDImageBased

Parameters:

opt - Calling snake optimizer.

Returns:

Optimization vector for this energy object.

getDerivativeX

public double getDerivativeX(double x,
                             double y)

Get x-derivative of external snake energy at given position using central differences.

Specified by:

getDerivativeX in class MTBSnakeEnergyCDImageBased

Parameters:

x - x-coordinate of pixel position

y - y-coordinate of pixel position

Returns:

x-derivative value at given position.

getDerivativeY

public double getDerivativeY(double x,
                             double y)

Get y-derivative of external snake energy at given position using central differences.

Specified by:

getDerivativeY in class MTBSnakeEnergyCDImageBased

Parameters:

x - x-coordinate of pixel position

y - y-coordinate of pixel position

Returns:

y-derivative value at given position.

normalizeEnergy

public void normalizeEnergy()

Normalize the external energy in a range [-1.0, 1.0].

Specified by:

normalizeEnergy in class MTBSnakeEnergyCDImageBased

toString

public String toString()

Description copied from interface: MTBSnakeEnergyDerivable

Get an identifier string for the energy object.

When meta parameters are saved to a file, configuration objects need to be converted to strings. Consequently, each snake energy should be associated with a unique and descriptive string for later reference.

Specified by:

toString in interface MTBSnakeEnergyComputable

Specified by:

toString in interface MTBSnakeEnergyDerivable

Overrides:

toString in class Object

Returns:

Identifier string.