org.jaitools.media.jai.regionalize
Class RegionalizeOpImage

java.lang.Object
  javax.media.jai.PlanarImage
      javax.media.jai.OpImage
          javax.media.jai.PointOpImage
              org.jaitools.media.jai.regionalize.RegionalizeOpImage

All Implemented Interfaces:

RenderedImage, javax.media.jai.ImageJAI, javax.media.jai.PropertyChangeEmitter, javax.media.jai.PropertySource, javax.media.jai.WritablePropertySource

public class RegionalizeOpImage
extends javax.media.jai.PointOpImage

An operator to identify regions of uniform value, within a user-specified tolerance, in the source image. Produces a destination image of these regions where pixel values are equal to region ID.

To avoid region numbering artefacts on image tile boundaries this operator imposes an order on tile computation (by column within row). If an arbitrary tile is requested by the caller, the operator first checks that all of the preceding tiles have been computed and cached, processing any that have not. The operator creates its own ExecutorService for sequential tile computations.

Each computed tile is cached using an instance of DiskMemTileCache. The caller can provide this to the operator via RenderingHints, or set it as the default TileCache using JAI.getDefaultInstance().setTileCache(). Otherwise the operator will create a DiskMemTileCache object for itself.

Since:

1.0

Version:

$Id: RegionalizeOpImage.java 1793 2011-06-23 03:45:24Z michael.bedward $

Author:

Michael Bedward

See Also:

RegionalizeDescriptor, RegionData

Field Summary

static int

NO_REGION Destination value indicating that a pixel does not belong to a region

Fields inherited from class javax.media.jai.OpImage

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

Fields inherited from class javax.media.jai.PlanarImage

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

Constructor Summary

RegionalizeOpImage(RenderedImage source, Map config, javax.media.jai.ImageLayout layout, int band, double tolerance, boolean diagonal)
Creates a new instance.

Method Summary

protected void	addTileToCache(int tileX, int tileY, Raster tile) This method is overridden to prevent it being used by clients.
Raster	computeTile(int tileX, int tileY)
Hashtable	getProperties() Gets the properties for this operator.
Object	getProperty(String name) Gets a property associated with this operator.
Class<?>	getPropertyClass(String name)
String[]	getPropertyNames()
Raster	getTile(int tileX, int tileY) Returns a tile of this image as a Raster.
protected Raster	getTileFromCache(int tileX, int tileY) This method is overridden to ensure that the cache is always addressed through the DiskMemImage being used by this operator, otherwise tile IDs calculated by the cache will vary with the perceived owner (the image or the operator) of the tile.
void	setTileCache(javax.media.jai.TileCache cache) Set the tile cache.

Methods inherited from class javax.media.jai.PointOpImage

dispose, isColormapOperation, mapDestRect, mapSourceRect, permitInPlaceOperation

Methods inherited from class javax.media.jai.OpImage

cancelTiles, computeRect, computeRect, computesUniqueTiles, createTile, getExpandedNumBands, getFormatTags, getOperationComputeType, getTileCache, getTileCacheMetric, getTileDependencies, getTileRecycler, getTiles, hasExtender, mapDestPoint, mapSourcePoint, prefetchTiles, queueTiles, recycleTile, vectorize, vectorize, vectorize

Methods inherited from class javax.media.jai.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, getPropertyNames, getSampleModel, getSinks, getSource, getSourceImage, getSourceObject, getSources, 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 java.lang.Object

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

Field Detail

NO_REGION

public static final int NO_REGION

Destination value indicating that a pixel does not belong to a region

See Also:

Constant Field Values

Constructor Detail

RegionalizeOpImage

public RegionalizeOpImage(RenderedImage source,
                          Map config,
                          javax.media.jai.ImageLayout layout,
                          int band,
                          double tolerance,
                          boolean diagonal)

Creates a new instance.

Parameters:

source - the source image

config - configurable attributes of the image (see AreaOpImage)

layout - an optional ImageLayout or null

band - the source image band to process

tolerance - the maximum absolute difference in value between the starting pixel for a region and other subsequent pixels added to it

diagonal - if true include sub-regions with only diagonal connectedness; if false require orthogonal connectedness

See Also:

RegionalizeDescriptor

Method Detail

getProperty

public Object getProperty(String name)

Gets a property associated with this operator. Use this to retrieve the RegionData object with the property name RegionalizeDescriptor.REGION_DATA_PROPERTY

Specified by:

getProperty in interface RenderedImage

Specified by:

getProperty in interface javax.media.jai.PropertySource

Overrides:

getProperty in class javax.media.jai.PlanarImage

Parameters:

name - property name

Returns:

the matching object or null if there was no match

getProperties

public Hashtable getProperties()

Gets the properties for this operator. These will include the RegionData object.

Overrides:

getProperties in class javax.media.jai.PlanarImage

Returns:

the properties

getPropertyClass

public Class<?> getPropertyClass(String name)

Specified by:

getPropertyClass in interface javax.media.jai.PropertySource

Overrides:

getPropertyClass in class javax.media.jai.PlanarImage

getPropertyNames

public String[] getPropertyNames()

Specified by:

getPropertyNames in interface RenderedImage

Specified by:

getPropertyNames in interface javax.media.jai.PropertySource

Overrides:

getPropertyNames in class javax.media.jai.PlanarImage

getTile

public Raster getTile(int tileX,
                      int tileY)

Returns a tile of this image as a Raster. If the requested tile is completely outside of this image's bounds, this method returns null.

The nature of the regionalizing algorithm means that to compute any tile other than the first (top left) we must compute all tiles to avoid region numbering artefacts across tile boundaries.

Specified by:

getTile in interface RenderedImage

Overrides:

getTile in class javax.media.jai.OpImage

Parameters:

tileX - The X index of the tile.

tileY - The Y index of the tile.

computeTile

public Raster computeTile(int tileX,
                          int tileY)

Overrides:

computeTile in class javax.media.jai.PointOpImage

addTileToCache

protected void addTileToCache(int tileX,
                              int tileY,
                              Raster tile)

This method is overridden to prevent it being used by clients.

Overrides:

addTileToCache in class javax.media.jai.OpImage

Parameters:

tileX - tile X ordinate

tileY - tile Y ordinate

tile - the tile

Throws:

UnsupportedOperationException - if called

getTileFromCache

protected Raster getTileFromCache(int tileX,
                                  int tileY)

This method is overridden to ensure that the cache is always addressed through the DiskMemImage being used by this operator, otherwise tile IDs calculated by the cache will vary with the perceived owner (the image or the operator) of the tile.

Overrides:

getTileFromCache in class javax.media.jai.OpImage

Parameters:

tileX - tile X coordinate

tileY - tile Y coordinate

Returns:

the requested tile

setTileCache

public void setTileCache(javax.media.jai.TileCache cache)

Set the tile cache. The supplied cache must be an instance of DiskMemTileCache.

Overrides:

setTileCache in class javax.media.jai.OpImage

Parameters:

cache - an instance of DiskMemTileCache

Throws:

IllegalArgumentException - if cache is null or not an instance of DiskMemTileCache