org.geotoolkit.image.jai
Class Hysteresis

Object
  PlanarImage
      OpImage
          UntiledOpImage
              Hysteresis

All Implemented Interfaces:

RenderedImage, ImageJAI, PropertyChangeEmitter, PropertySource, WritablePropertySource

public class Hysteresis
extends UntiledOpImage

Applies a hysteresis threshold on an image. This operation is defined by an upper threshold, high, and a lower threshold, low. If a pixel value is equals or higher than high, it is keep unchanged. If a pixel value is lower than low, it is replaced by the pad value. If a pixel value is between low and high, then this pixel is called "indeterminate". Its value is keep unchanged only if this pixel is either a neighbor of a pixel having a value equals or higher than high, or a neighbor of an other indeterminate pixel which has been determined close to a pixel having a value equals or higher than high in a previous iteration. This search is performed in an iterative manner until there is no more indeterminate pixels having satisfying neighbor.

Since:

2.1

Version:

3.00

Author:

Lionel Flahaut (IRD), Martin Desruisseaux (IRD)

Module:

coverage/geotk-coverage (download)

View source code for this class

Field Summary

protected double	high The upper threshold value, inclusive.
protected double	low The lower threshold value, inclusive.
static String	OPERATION_NAME The name of this operation in the JAI registry.
protected double	padValue The value to give to filtered pixel.

Fields inherited from class OpImage

cache, cobbleSources, OP_COMPUTE_BOUND, OP_IO_BOUND, OP_NETWORK_BOUND, tileCacheMetric, tileRecycler

Fields inherited from class PlanarImage

colorModel, eventManager, height, minX, minY, properties, sampleModel, tileFactory, tileGridXOffset, tileGridYOffset, tileHeight, tileWidth, width

Constructor Summary

Hysteresis(RenderedImage source, ImageLayout layout, Map<?,?> configuration, double low, double high, double padValue)
Constructs a new Hysterisis filter for the given image.

Method Summary

protected void	computeImage(Raster[] sources, WritableRaster dest, Rectangle destRect) Computes a rectangle of outputs.
Vector<RenderedImage>	getSources() Returns the source images.

Methods inherited from class UntiledOpImage

computeTile, getTileDependencies, mapDestRect, mapSourceRect

Methods inherited from class OpImage

addTileToCache, cancelTiles, computeRect, computeRect, computesUniqueTiles, createTile, dispose, getExpandedNumBands, getFormatTags, getOperationComputeType, getTile, getTileCache, getTileCacheMetric, getTileFromCache, getTileRecycler, getTiles, hasExtender, mapDestPoint, mapSourcePoint, prefetchTiles, queueTiles, recycleTile, setTileCache, vectorize, vectorize, vectorize

Methods inherited from class PlanarImage

addPropertyChangeListener, addPropertyChangeListener, addSink, addSink, addSource, addTileComputationListener, copyData, copyData, copyExtendedData, createColorModel, createSnapshot, createWritableRaster, finalize, getAsBufferedImage, getAsBufferedImage, getBounds, getColorModel, getData, getData, getDefaultColorModel, getExtendedData, getGraphics, getHeight, getImageID, getMaxTileX, getMaxTileY, getMaxX, getMaxY, getMinTileX, getMinTileY, getMinX, getMinY, getNumBands, getNumSources, getNumXTiles, getNumYTiles, getProperties, getProperty, getPropertyClass, getPropertyNames, getPropertyNames, getSampleModel, getSinks, getSource, getSourceImage, getSourceObject, getSplits, getTileComputationListeners, getTileFactory, getTileGridXOffset, getTileGridYOffset, getTileHeight, getTileIndices, getTileRect, getTiles, getTileWidth, getWidth, overlapsMultipleTiles, removeProperty, removePropertyChangeListener, removePropertyChangeListener, removeSink, removeSink, removeSinks, removeSource, removeSources, removeTileComputationListener, setImageLayout, setProperties, setProperty, setSource, setSources, tileXToX, tileXToX, tileYToY, tileYToY, toString, wrapRenderedImage, XToTileX, XToTileX, YToTileY, YToTileY

Methods inherited from class Object

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

Field Detail

OPERATION_NAME

public static final String OPERATION_NAME

The name of this operation in the JAI registry. This is "org.geotoolkit.Hysteresis".

See Also:

Constant Field Values

low

protected final double low

The lower threshold value, inclusive. Pixels having a value lower than this value will be set to the padValue.

high

protected final double high

The upper threshold value, inclusive. Pixels having a value equals or higher than this value will be keep unchanged.

padValue

protected final double padValue

The value to give to filtered pixel.

Constructor Detail

Hysteresis

public Hysteresis(RenderedImage source,
                  ImageLayout layout,
                  Map<?,?> configuration,
                  double low,
                  double high,
                  double padValue)

Constructs a new Hysterisis filter for the given image. While this constructor is public, it should usually not be invoked directly. You should use JAI factory methods instead.

Parameters:

source - The source image.

layout - The image layout.

configuration - The image properties and rendering hints.

low - The lower threshold value, inclusive.

high - The upper threshold value, inclusive.

padValue - The value to give to filtered pixel.

Method Detail

getSources

public Vector<RenderedImage> getSources()

Returns the source images.

Specified by:

getSources in interface RenderedImage

Overrides:

getSources in class PlanarImage

computeImage

protected void computeImage(Raster[] sources,
                            WritableRaster dest,
                            Rectangle destRect)

Computes a rectangle of outputs.

Specified by:

computeImage in class UntiledOpImage

Parameters:

sources - The source images. Should be an array of length 1.

dest - The raster to be filled in.

destRect - The region within the raster to be filled.