org.opengis.coverage.processing
Interface GridCoverageProcessor

public interface GridCoverageProcessor

Provides operations for different ways of accessing the grid coverage values as well as image processing functionality. The list of available processing operations is implementation dependent. The interface has a discovery mechanism to determine the available processing operations. These processing operations will transform values within a single sample dimension, and leave the values in other sample dimensions unaffected. The modified sample dimension may also change its type (e.g. from UNSIGNED_4BITS to UNSIGNED_1BIT). The actual underlying grid data remains unchanged.

The interface has been designed to allow the adaptations to be done in a "pipe-lined" manner. The interface operates on GridCoverage to create new a GridCoverage. The interface does not need to make a copy of the source grid data. Instead, it can return a grid coverage object which applies the adaptations on the original grid coverage whenever a block of data is requested. In this way, a pipeline of several grid coverages can be constructed cheaply.

This interface can perform any of the following:

• Change the number of bands being accessed.
• Change the value sequencing in which the grid values are retrieved.
• Allow re-sampling of the grid coverage for a different geometry. Creating a new GridCoverage with different grid geometry allows for reprojecting the grid coverage to another projection and another georeferencing type, resampling to another cell resolution and subsetting the grid coverage.
• Modify the way the grid values are accessed (filtered, classified...).
• Change the interpolation method used when evaluating points which fall between grid cells.
• Filtering.
• Image enhancements.
• etc.

Version:

Grid Coverage specification 1.0

Author:

OpenGIS® consortium

UML identifier (abstract type): GP_GridCoverageProcessor

Method Summary

GridAnalysis	analyse(GridCoverage gridCoverage) Creates a GridAnalysis interface from a grid coverage.
GridCoverage	doOperation(String operationName, GeneralParameterValue[] parameters) Apply a process operation to a grid coverage.
String[]	getMetadataNames() Retrieve the list of metadata keywords for the interface.
String	getMetadataValue(String name) Retrieve the metadata value for a given metadata name.
int	getNumOperations() The number of operations supported by the GridCoverageProcessor.
Operation	getOperation(int index) Retrieve a grid processing operation information.

Method Detail

getMetadataNames

String[] getMetadataNames()

Retrieve the list of metadata keywords for the interface. An empty list will returned if no metadata is available.

Returns:

The list of metadata keywords for the interface.

UML identifier (mandatory attribute): metadataNames

getMetadataValue

String getMetadataValue(String name)
                        throws MetadataNameNotFoundException

Retrieve the metadata value for a given metadata name.

Parameters:

name - Metadata keyword for which to retrieve metadata.

Returns:

The metadata value for a given metadata name.

Throws:

MetadataNameNotFoundException - if there is no value for the specified metadata name.

UML identifier (operation): getMetadataValue

getNumOperations

int getNumOperations()

The number of operations supported by the GridCoverageProcessor.

Returns:

The number of operations supported by the GridCoverageProcessor.

UML identifier (mandatory attribute): numOperations

getOperation

Operation getOperation(int index)
                       throws IndexOutOfBoundsException

Retrieve a grid processing operation information. The operation information will contain the name of the operation as well as a list of its parameters.

Parameters:

index - Index for which to retrieve the operation information.

Returns:

A grid processing operation information.

Throws:

IndexOutOfBoundsException - if index is out of bounds.

UML identifier (operation): getOperation

analyse

GridAnalysis analyse(GridCoverage gridCoverage)

Creates a GridAnalysis interface from a grid coverage. This allows grid analysis functions to be performed on a grid coverage.

Parameters:

gridCoverage - Grid coverage on which the analysis will be performed.

Returns:

A new GridAnalysis interface.

UML identifier (operation): analyze

doOperation

GridCoverage doOperation(String operationName,
                         GeneralParameterValue[] parameters)
                         throws OperationNotFoundException,
                                ParameterNotFoundException,
                                InvalidParameterNameException,
                                InvalidParameterValueException

Apply a process operation to a grid coverage.

Parameters:

operationName - Name of the operation to be applied to the grid coverage.

parameters - List of name value pairs for the parameters required for the operation.

Returns:

The grid coverage which has been applied the process operation.

Throws:

OperationNotFoundException - if name is not a know operation.

ParameterNotFoundException - if a parameter was required for the operation but was not provided in the parameters list.

InvalidParameterNameException - if a parameter doesn't have a recognized name.

InvalidParameterValueException - if a parameter doesn't have a valid value.

UML identifier (operation): doOperation