Module imagingbook.common

Package imagingbook.common.filter.examples

Class FilterProgressExample

java.lang.Object

imagingbook.common.filter.generic.GenericFilter

imagingbook.common.filter.generic.GenericFilterVector

imagingbook.common.filter.examples.FilterProgressExample

All Implemented Interfaces:

ProgressReporter

public class FilterProgressExample
extends GenericFilterVector

This class defines a custom filter implementing GenericFilterVector that reports its progress, which is queried by a ProgressMonitor in the main(String[]) method.

In this example the work required for processing each SINGLE pixel is assumed to be substantial and progress reporting thus goes all the way down to the single pixel level. Method GenericFilter.getProgress() in this case reports how much of the work for the current pixel is already completed. Note that this is for demonstration only and such fine granularity is usually not needed. Typically method GenericFilter.getProgress() needs not to be overridden or may be defined to return always 1.

The OVERALL filter progress (which depends on the image size and the number of required filter passes) is calculated automatically by the associated super classes.

See Also:

• ProgressMonitor
• ProgressMonitorExample
• ConsoleProgressMonitor

Constructor Summary

Constructors

Constructor	Description
FilterProgressExample()

Method Summary

Modifier and Type	Method	Description
protected float[]	doPixel(PixelPack source, int u, int v)	This method defines the steps to be performed for a single image pixel and must be implemented by any concrete sub-class.
protected void	initFilter(PixelPack source, PixelPack target)	This method is called once at the start of the filter execution.
protected void	initPass(PixelPack source, PixelPack target)	This method is called once at the start of each filter pass.
static void	main(String[] args)	Main method for demonstration only.
protected int	passesRequired()	Returns the necessary number of passes, which may change during execution of the filter.
protected double	reportProgress()	This method is called asynchonously and may be overridden by the terminal filter class if it does extensive work that should be monitored.

Methods inherited from class imagingbook.common.filter.generic.GenericFilterVector

reportProgress, runPass

Methods inherited from class imagingbook.common.filter.generic.GenericFilter

abort, applyTo, applyTo, applyTo, closeFilter, getDepth, getHeight, getPass, getProgress, getWidth

Methods inherited from class java.lang.Object

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

Constructor Details

FilterProgressExample

public FilterProgressExample()

Method Details

initFilter

protected void initFilter(PixelPack source,
 PixelPack target)

Description copied from class: GenericFilter

This method is called once at the start of the filter execution. It does nothing by default. Concrete filter classes should override this method, e.g., for setting up temporary data structures.

Overrides:

initFilter in class GenericFilter

Parameters:

source - the image source data

target - the image target data

initPass

protected void initPass(PixelPack source,
 PixelPack target)

Description copied from class: GenericFilter

This method is called once at the start of each filter pass. It does nothing by default. Concrete filter classes should override this method if needed.

Overrides:

initPass in class GenericFilter

Parameters:

source - the image source data

target - the image target data

passesRequired

protected int passesRequired()

Description copied from class: GenericFilter

Returns the necessary number of passes, which may change during execution of the filter. The value 1 is returned by default. Multi-pass filters must override this method. The filter terminates as soon as the requested number of passes is reached. This this method can be used to terminate filter execution once some desired state has been reached (e.g., convergence). See also GenericFilter.getPass().

Overrides:

passesRequired in class GenericFilter

Returns:

the required number of filter passes

doPixel

protected float[] doPixel(PixelPack source,
 int u,
 int v)

Description copied from class: GenericFilterVector

This method defines the steps to be performed for a single image pixel and must be implemented by any concrete sub-class. The source data are passed as a PixelPack container, which holds the pixel values of all image components. The method PixelPack.getPix(int, int) should be used to read individual pixel vectors. These data should not be modified but the (float[]) result of the single-pixel calculation must be returned. Implementations are free to return the same float-array at each invocation, i.e., there is no need to allocate a new array every time.

Specified by:

doPixel in class GenericFilterVector

Parameters:

source - the vector-valued image data

u - the current x-position

v - the current y-position

Returns:

the result of the filter calculation for this pixel

reportProgress

protected double reportProgress()

This method is called asynchonously and may be overridden by the terminal filter class if it does extensive work that should be monitored. In this case the method must return a value between 0 and 1, reflecting the degree of completion (only of the final class's subtask) at the time of invocation. Normally this is not necessary, since the intermediate classes return their own progress state (for the less granular tasks) anyways. The default implementations returns 0 (progress). See FilterProgressExample for an example.

Note: This method returns the filter's progress (degree of completion) for the current pixel (see doPixel(PixelPack, int, int)). Typically this fine granularity is not relevant and the method should either return 1 or not be overridden at all (removed).

Overrides:

reportProgress in class GenericFilter

Returns:

the degree of completion (0,...,1)

main

public static void main(String[] args)

Main method for demonstration only.

Parameters:

args - ignored