javax.media.jai.operator
Class DivideByConstDescriptor

java.lang.Object
  javax.media.jai.OperationDescriptorImpl
      javax.media.jai.operator.DivideByConstDescriptor

All Implemented Interfaces:

OperationDescriptor, RegistryElementDescriptor, Serializable

public class DivideByConstDescriptor

extends OperationDescriptorImpl

An OperationDescriptor describing the "DivideByConst" operation.

The DivideByConst operation takes one rendered or renderable source image and an array of double constants, and divides every pixel of the same band of the source by the constant from the corresponding array entry. If the number of constants supplied is less than the number of bands of the destination, then the constant from entry 0 is applied to all the bands. Otherwise, a constant from a different entry is applied to each band.

In case of division by 0, if the numerator is 0, then the result is set to 0; otherwise, the result is set to the maximum value supported by the destination data type.

By default, the destination image bound, data type, and number of bands are the same as the source image. If the result of the operation underflows/overflows the minimum/maximum value supported by the destination data type, then it will be clamped to the minimum/maximum value respectively.

The destination pixel values are defined by the pseudocode:

 if (constants.length < dstNumBands) {
     dst[x][y][b] = srcs[x][y][b]/constants[0];
 } else {
     dst[x][y][b] = srcs[x][y][b]/constants[b];
 }
 

Resource List

Name	Value
GlobalName	DivideByConst
LocalName	DivideByConst
Vendor	com.sun.media.jai
Description	Divides an image by constants.
DocURL	http://java.sun.com/products/java-media/jai/forDevelopers/jai-apidocs/javax/media/jai/operator/DivideByConstDescriptor.html
Version	1.0
arg0Desc	The constants to be divided by.

Parameter List

Name	Class Type	Default Value
constants	double[]	{1.0}

See Also:

OperationDescriptor, Serialized Form

Field Summary

Fields inherited from class javax.media.jai.OperationDescriptorImpl

sourceNames, supportedModes

Fields inherited from interface javax.media.jai.OperationDescriptor

NO_PARAMETER_DEFAULT

Constructor Summary

DivideByConstDescriptor()
Constructor.

Method Summary

static RenderedOp	create(RenderedImage source0, double[] constants, RenderingHints hints) Divides an image by constants.
static RenderableOp	createRenderable(RenderableImage source0, double[] constants, RenderingHints hints) Divides an image by constants.
boolean	isRenderableSupported() Returns true since renderable operation is supported.
protected boolean	validateParameters(ParameterBlock args, StringBuffer message) Validates the input parameters.

Methods inherited from class javax.media.jai.OperationDescriptorImpl

arePropertiesSupported, getDefaultSourceClass, getDestClass, getDestClass, getInvalidRegion, getName, getNumParameters, getNumSources, getParamClasses, getParamDefaults, getParamDefaultValue, getParameterListDescriptor, getParamMaxValue, getParamMinValue, getParamNames, getPropertyGenerators, getPropertyGenerators, getRenderableDestClass, getRenderableSourceClasses, getResourceBundle, getResources, getSourceClasses, getSourceClasses, getSourceNames, getSupportedModes, isImmediate, isModeSupported, isRenderedSupported, makeDefaultSourceClassList, validateArguments, validateArguments, validateParameters, validateRenderableArguments, validateRenderableSources, validateSources, validateSources

Methods inherited from class java.lang.Object

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

Constructor Detail

DivideByConstDescriptor

public DivideByConstDescriptor()

Constructor.

Method Detail

isRenderableSupported

public boolean isRenderableSupported()

Returns true since renderable operation is supported.

Specified by:

isRenderableSupported in interface OperationDescriptor

Overrides:

isRenderableSupported in class OperationDescriptorImpl

See Also:

OperationDescriptorImpl.isModeSupported(java.lang.String)

validateParameters

protected boolean validateParameters(ParameterBlock args,
                                     StringBuffer message)

Validates the input parameters.

In addition to the standard checks performed by the superclass method, this method checks that the length of the "constants" array is at least 1.

Overrides:

validateParameters in class OperationDescriptorImpl

See Also:

OperationDescriptorImpl.validateParameters(java.lang.String, java.awt.image.renderable.ParameterBlock, java.lang.StringBuffer)

create

public static RenderedOp create(RenderedImage source0,
                                double[] constants,
                                RenderingHints hints)

Divides an image by constants.

Creates a ParameterBlockJAI from all supplied arguments except hints and invokes JAI.create(String,ParameterBlock,RenderingHints).

Parameters:

source0 - RenderedImage source 0.

constants - The constants to be divided by. May be null.

hints - The RenderingHints to use. May be null.

Returns:

The RenderedOp destination.

Throws:

IllegalArgumentException - if source0 is null.

See Also:

JAI, ParameterBlockJAI, RenderedOp

createRenderable

public static RenderableOp createRenderable(RenderableImage source0,
                                            double[] constants,
                                            RenderingHints hints)

Divides an image by constants.

Creates a ParameterBlockJAI from all supplied arguments except hints and invokes JAI.createRenderable(String,ParameterBlock,RenderingHints).

Parameters:

source0 - RenderableImage source 0.

constants - The constants to be divided by. May be null.

hints - The RenderingHints to use. May be null.

Returns:

The RenderableOp destination.

Throws:

IllegalArgumentException - if source0 is null.

See Also:

JAI, ParameterBlockJAI, RenderableOp