org.geotoolkit.coverage.processing
Class IndexColorOperation

Object
  AbstractOperation
      Operation2D
          IndexColorOperation

All Implemented Interfaces:

Serializable, Operation

Direct Known Subclasses:

Recolor

@Immutable
public abstract class IndexColorOperation
extends Operation2D

Operation applied on the IndexColorModel of the image backing the source grid coverage. The doOperation method extracts the color map of the source coverage as an array of ARGB values, passes that array to transformColormap and creates a new grid coverage using the new colors.

Since:

1.2

Version:

3.14

Author:

Martin Desruisseaux (IRD)

See Also:

Serialized Form

Module:

coverage/geotk-coverage (download)

View source code for this class

Field Summary

Fields inherited from class Operation2D

PRIMARY_SOURCE_INDEX, SOURCE_0, SOURCE_1, SOURCE_2

Fields inherited from class AbstractOperation

descriptor

Constructor Summary

protected

IndexColorOperation(DefaultParameterDescriptorGroup descriptor) Constructs an operation.

Method Summary

protected Coverage	doOperation(ParameterValueGroup parameters, Hints hints) Performs the color transformation.
protected ViewType	getComputationView(ParameterValueGroup parameters) Returns ViewType.RENDERED as the preferred view for computation purpose.
protected abstract GridSampleDimension	transformColormap(int[] ARGB, int band, GridSampleDimension sampleDimension, ParameterValueGroup parameters) Transforms the supplied RGB colors.

Methods inherited from class Operation2D

extractSources, extractSources

Methods inherited from class AbstractOperation

equals, getDescription, getDocURL, getName, getNumSources, getParameters, getVendor, getVersion, hashCode, toString

Methods inherited from class Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

IndexColorOperation

protected IndexColorOperation(DefaultParameterDescriptorGroup descriptor)

Constructs an operation. The operation name will be the same than the parameter descriptor name.

Parameters:

descriptor - The parameters descriptor.

Method Detail

getComputationView

protected ViewType getComputationView(ParameterValueGroup parameters)

Returns ViewType.RENDERED as the preferred view for computation purpose.

Overrides:

getComputationView in class Operation2D

Parameters:

parameters - The parameters supplied by the user to the doOperation method.

Returns:

The view on which computation should be performed.

See Also:

GridCoverage2D.view(ViewType)

doOperation

protected Coverage doOperation(ParameterValueGroup parameters,
                               Hints hints)
                        throws IllegalArgumentException

Performs the color transformation. This method invokes the transformColormap(...) method with the ARGB colors found in the source image, its GridSampleDimension and the parameters supplied to this method. The new colors returned by transformColormap are used for creating a grid coverage backed by and image using a new IndexColorModel.

Specified by:

doOperation in class AbstractOperation

Parameters:

parameters - The parameters.

hints - Rendering hints (ignored in this implementation).

Returns:

The result as a coverage.

Throws:

IllegalArgumentException - if the image do not use an IndexColorModel.

transformColormap

protected abstract GridSampleDimension transformColormap(int[] ARGB,
                                                         int band,
                                                         GridSampleDimension sampleDimension,
                                                         ParameterValueGroup parameters)

Transforms the supplied RGB colors. This method is automatically invoked by doOperation(...) for each band in the source GridCoverage2D. The ARGB array contains the ARGB values from the current source and should be overridden with new ARGB values for the destination image.

This method is usually invoked only once, since images backed by IndexColorModel normally have only one band. However it may happen that an image contains additional "invisible" bands, in which case this method will be invoked for those bands as well.

Parameters:

ARGB - Alpha, Red, Green and Blue components to transform.

band - The band number, from 0 to the number of bands in the image -1.

sampleDimension - The sample dimension of band band.

parameters - The user-supplied parameters.

Returns:

A sample dimension identical to sampleDimension except for the colors. Subclasses may conservatively returns sampleDimension.