org.geotools.coverage.processing.operation
Class Extrema

Object
  AbstractOperation
      Operation2D
          OperationJAI
              BaseStatisticsOperationJAI
                  Extrema

All Implemented Interfaces:

Serializable, Operation

public class Extrema
extends BaseStatisticsOperationJAI

This operation simply wraps JAI Extrema operations described by ExtremaDescriptor inside a GeoTools operation in order to make it spatial-aware.

For the moment this is a very simple wrap. Plans on the 2.4 and successive versions of this operation are to add the ability to use spatial ROIs and to specific Spatial subsampling. As of now, ROI has to be a Java2D Shape subclass and the parameters to control x and y subsamplings got to be Integer, which means pixel-aware.

For more information on how the underlying JAI operators works you can have a look here: ExtremaDescriptor

How to use this operation Here is a very simple example on how to use this operation in order to the minimum and maximum of the source coverage. final OperationJAI op=new OperationJAI("Extrema"); ParameterValueGroup params = op.getParameters(); params.parameter("Source").setValue(coverage); coverage=(GridCoverage2D) op.doOperation(params,null); System.out.println(((double[])coverage.getProperty("minimum"))[0]); System.out.println(((double[])coverage.getProperty("minimum"))[1]); System.out.println(((double[])coverage.getProperty("minimum"))[2]); System.out.println(((double[])coverage.getProperty("maximum"))[0]); System.out.println(((double[])coverage.getProperty("maximum"))[1]); System.out.println(((double[])coverage.getProperty("maximum"))[2]);

Since:

2.4

Author:

Simone Giannecchini

See Also:

Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from class OperationJAI

OperationJAI.Parameters

Field Summary

static String	GT_SYNTHETIC_PROPERTY_MAX_LOCATIONS Locations of max values.
static String	GT_SYNTHETIC_PROPERTY_MAXIMUM String key for getting the maximum vector.
static String	GT_SYNTHETIC_PROPERTY_MIN_LOCATIONS Locations of min values.
static String	GT_SYNTHETIC_PROPERTY_MINIMUM String key for getting the minimum vector.
static Logger	LOGGER Logger for this class.

Fields inherited from class BaseStatisticsOperationJAI

ROI, SPATIAL_SUBSAMPLING_X, SPATIAL_SUBSAMPLING_Y

Fields inherited from class OperationJAI

operation, RENDERED_MODE

Fields inherited from class Operation2D

PRIMARY_SOURCE_INDEX, SOURCE_0

Fields inherited from class AbstractOperation

descriptor

Constructor Summary

Extrema()
Constructs a default "Extrema" operation.

Method Summary

protected boolean	computeOnGeophysicsValues(ParameterValueGroup parameters) This operation MUST be performed on the geophysics data for this GridCoverage2D.
protected Map<String,?>	getProperties(RenderedImage data, CoordinateReferenceSystem crs, InternationalString name, MathTransform toCRS, GridCoverage2D[] sources, OperationJAI.Parameters parameters) Prepare the minimum and maximum properties for this extream operation.

Methods inherited from class BaseStatisticsOperationJAI

prepareParameters

Methods inherited from class OperationJAI

createRenderedImage, deriveCategory, deriveGridCoverage, deriveName, deriveRange, deriveSampleDimension, deriveUnit, doOperation, equals, getJAI, getOperationDescriptor, getQuantitative, resampleToCommonGeometry

Methods inherited from class Operation2D

extractSources, getFactory

Methods inherited from class AbstractOperation

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

Methods inherited from class Object

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

Field Detail

LOGGER

public static final Logger LOGGER

Logger for this class.

GT_SYNTHETIC_PROPERTY_MINIMUM

public static final String GT_SYNTHETIC_PROPERTY_MINIMUM

String key for getting the minimum vector.

See Also:

Constant Field Values

GT_SYNTHETIC_PROPERTY_MAXIMUM

public static final String GT_SYNTHETIC_PROPERTY_MAXIMUM

String key for getting the maximum vector.

See Also:

Constant Field Values

GT_SYNTHETIC_PROPERTY_MIN_LOCATIONS

public static final String GT_SYNTHETIC_PROPERTY_MIN_LOCATIONS

Locations of min values.

See Also:

Constant Field Values

GT_SYNTHETIC_PROPERTY_MAX_LOCATIONS

public static final String GT_SYNTHETIC_PROPERTY_MAX_LOCATIONS

Locations of max values.

See Also:

Constant Field Values

Constructor Detail

Extrema

public Extrema()
        throws OperationNotFoundException

Constructs a default "Extrema" operation.

Throws:

OperationNotFoundException

Method Detail

computeOnGeophysicsValues

protected boolean computeOnGeophysicsValues(ParameterValueGroup parameters)

This operation MUST be performed on the geophysics data for this GridCoverage2D.

Overrides:

computeOnGeophysicsValues in class Operation2D

Parameters:

parameters - ParameterValueGroup that describes this operation

Returns:

always true.

See Also:

GridCoverage2D.geophysics(boolean)

getProperties

protected Map<String,?> getProperties(RenderedImage data,
                                      CoordinateReferenceSystem crs,
                                      InternationalString name,
                                      MathTransform toCRS,
                                      GridCoverage2D[] sources,
                                      OperationJAI.Parameters parameters)

Prepare the minimum and maximum properties for this extream operation.

See ExtremaDescriptor for more info.

Overrides:

getProperties in class OperationJAI

Parameters:

data - The RenderedImage created by this operation.

crs - The coordinate reference system assigned to the coverage this OperationJAI will produce.

name - The name assigned to the coverage this OperationJAI will produce.

toCRS - The transform from grid to crs to be assigned to the coverage this OperationJAI will produce.

sources - The sources to be assigned to the coverage this OperationJAI will produce.

parameters - The parameters that were used by this OperationJAI.

Returns:

a Map with the properties generated by this OperationJAI or null if we haven't any.

See Also:

OperationJAI#getProperties(RenderedImage, CoordinateReferenceSystem, InternationalString, MathTransform, GridCoverage2D[], org.geotools.coverage.processing.OperationJAI.Parameters),