java.lang.Object
- gov.nih.mipav.model.algorithms.levelset.LsePdeFilter

Direct Known Subclasses:

LsePdeFilter2, LsePdeFilter3
```
public abstract class LsePdeFilter
extends java.lang.Object
```
The abstract base class for finite-difference-based solvers for partial differential equations. This system exists to support level-set evolution for image segmentation.

Version:

0.1 November 7, 2006

Author:

David Eberly

Field Summary

Fields
Modifier and Type	Field	Description
`protected int`	`m_eScaleType`	The type of image scaling used during filter construction.
`protected float`	`m_fBorderValue`	When set to Float.MAX_VALUE, Neumann conditions are in use (zero-valued derivatives on the image border).
`protected float`	`m_fMin`	The minimum image value.
`protected float`	`m_fOffset`	The offset used in scaling the image data.
`protected float`	`m_fScale`	The scale factor used in scaling the image data.
`protected float`	`m_fTimeStep`	The time step for the PDE solver.
`protected int`	`m_iQuantity`	The number of image elements.
`static int`	`NONE`	Scale type: no scaling.
`static int`	`PRESERVE_ZERO`	Scale type: max > -min: d' = d/max in [min/max,1] max < -min: d' = -d/min in [-1,-max/min]
`static int`	`SYMMETRIC`	Scale type: d' = -1 + 2*(d-min)/(max-min) in [-1,1]
`static int`	`UNIT`	Scale type: d' = (d-min)/(max-min) in [0,1]

Constructor Summary

Constructors
Modifier	Constructor	Description
`protected`	`LsePdeFilter(int iQuantity, float[] afData, float fBorderValue, int eScaleType)`	Creates a new PDE filter object.

Method Summary

All Methods Instance Methods Abstract Methods Concrete Methods
Modifier and Type	Method	Description
`float`	`getBorderValue()`	Get the image border value.
`int`	`getQuantity()`	Get the number of image elements.
`int`	`getScaleType()`	Get the type of image scaling.
`float`	`getTimeStep()`	Get the time step for the PDE solver.
`protected abstract void`	`onPostUpdate()`	An abstract function that allows derived classes to implement any desired behavior after the PDE solver applies its update function.
`protected abstract void`	`onPreUpdate()`	An abstract function that allows derived classes to implement any desired behavior before the PDE solver applies its update function.
`protected abstract void`	`onUpdate()`	An abstract function for the update function of the PDE solver.
`void`	`setTimeStep(float fTimeStep)`	Set the time step for the PDE solver.
`void`	`update()`	The entry point to updating the PDE solver.

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

- Field Detail
  - NONE
```
public static final int NONE
```
    Scale type: no scaling.
    
    See Also:
    
    Constant Field Values
  - UNIT
```
public static final int UNIT
```
    Scale type: d' = (d-min)/(max-min) in [0,1]
    
    See Also:
    
    Constant Field Values
  - SYMMETRIC
```
public static final int SYMMETRIC
```
    Scale type: d' = -1 + 2*(d-min)/(max-min) in [-1,1]
    
    See Also:
    
    Constant Field Values
  - PRESERVE_ZERO
```
public static final int PRESERVE_ZERO
```
    Scale type: max > -min: d' = d/max in [min/max,1] max < -min: d' = -d/min in [-1,-max/min]
    
    See Also:
    
    Constant Field Values
  - m_iQuantity
```
protected int m_iQuantity
```
    The number of image elements.
  - m_fBorderValue
```
protected float m_fBorderValue
```
    When set to Float.MAX_VALUE, Neumann conditions are in use (zero-valued derivatives on the image border). Dirichlet conditions are used, otherwise (image is constant on the border).
  - m_eScaleType
```
protected int m_eScaleType
```
    The type of image scaling used during filter construction.
  - m_fMin
```
protected float m_fMin
```
    The minimum image value.
  - m_fOffset
```
protected float m_fOffset
```
    The offset used in scaling the image data.
  - m_fScale
```
protected float m_fScale
```
    The scale factor used in scaling the image data.
  - m_fTimeStep
```
protected float m_fTimeStep
```
    The time step for the PDE solver. The stability of an algorithm depends on the magnitude of the time step but the magnitude itself depends on the algorithm.
- Constructor Detail
  - LsePdeFilter
```
protected LsePdeFilter(int iQuantity,
                       float[] afData,
                       float fBorderValue,
                       int eScaleType)
```
    Creates a new PDE filter object.
    
    Parameters:
    
    iQuantity - The number of image elements.
    
    afData - The image elements, stored in lexicographical order.
    
    fBorderValue - Specifies how to handle the image value. When set to Float.MAX_VALUE, Neumann conditions are in use, in which case zero-valued derivatives are assumed on the image border. Otherwise, Dirichlet conditions are used, in which case the image is assumed to be constant on the border with value specified by fBorderValue.
    
    eScaleType - The type of scaling to apply to the input image. The choices are NONE, UNIT, SYMMETRIC, or PRESERVE_ZERO.
- Method Detail
  - getQuantity
```
public final int getQuantity()
```
    Get the number of image elements.
    
    Returns:
    
    The number of image elements.
  - getBorderValue
```
public final float getBorderValue()
```
    Get the image border value.
    
    Returns:
    
    The image border value.
  - getScaleType
```
public final int getScaleType()
```
    Get the type of image scaling.
    
    Returns:
    
    The type of image scaling.
  - setTimeStep
```
public final void setTimeStep(float fTimeStep)
```
    Set the time step for the PDE solver.
    
    Parameters:
    
    fTimeStep - The time step for the PDE solver. It must be a positive number. Its maximum-allowed size depends on the specific algorithm.
  - getTimeStep
```
public final float getTimeStep()
```
    Get the time step for the PDE solver.
    
    Returns:
    
    The time step for the PDE solver.
  - update
```
public void update()
```
    The entry point to updating the PDE solver. This function calls OnPreUpdate, OnUpdate, and OnPostUpdate, in that order.
  - onPreUpdate
```
protected abstract void onPreUpdate()
```
    An abstract function that allows derived classes to implement any desired behavior before the PDE solver applies its update function. The derived classes for 2D and 3D implement this to recompute the boundary values when Neumann conditions are used. If derived classes built on top of the 2D or 3D classes implement this also, they must call the base-class OnPreUpdate first.
  - onUpdate
```
protected abstract void onUpdate()
```
    An abstract function for the update function of the PDE solver. The derived classes for 2D and 3D implement this to iterate over the image elements, updating an element only if it is not masked out.
  - onPostUpdate
```
protected abstract void onPostUpdate()
```
    An abstract function that allows derived classes to implement any desired behavior after the PDE solver applies its update function. The derived classes for 2D and 3D implement this to swap the buffers for the next pass. If derived classes built on top of the 2D or 3D classes implement this also, they must call the base-class OnPostUpdate last.

Class LsePdeFilter

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

NONE

UNIT

SYMMETRIC

PRESERVE_ZERO

m_iQuantity

m_fBorderValue

m_eScaleType

m_fMin

m_fOffset

m_fScale

m_fTimeStep

Constructor Detail

LsePdeFilter

Method Detail

getQuantity

getBorderValue

getScaleType

setTimeStep

getTimeStep

update

onPreUpdate

onUpdate

onPostUpdate