Package org.geotools.coverage.processing

Class OperationJAI

Object
AbstractOperation
Operation2D
OperationJAI
All Implemented Interfaces:
Serializable, Operation
Direct Known Subclasses:
AddConst, BandMerge, BaseMathOperationJAI, BaseScaleOperationJAI, BaseStatisticsOperationJAI, BilevelOperation, Convolve, DivideByConst, FilterOperation, MaxFilter, MedianFilter, MinFilter, Mosaic, MultiplyConst, Rescale, ShadedRelief, SubtractConst, SubtractFromConst, TransparencyFill
public class OperationJAI extends Operation2D
Wraps a JAI's OperationDescriptor for interoperability with Java Advanced Imaging. This class help to leverage the rich set of ImageN operators in an GeoAPI framework. OperationJAI inherits operation name and argument types from OperationDescriptor, except the source argument type (usually RenderedImage.class) which is set to GridCoverage2D.class. If there is only one source argument, it will be renamed "source" for better compliance with OpenGIS usage.

The entry point for applying an operation is the usual doOperation method. The default implementation forward the call to other methods for different bits of tasks, resulting in the following chain of calls:

doOperation:  the entry point.
resampleToCommonGeometry:  reprojects all sources to the same coordinate reference system.
deriveGridCoverage:  gets the destination properties.
deriveSampleDimension:  gets the destination sample dimensions.
deriveCategory:  gets the destination categories.
deriveRange:  gets the expected range of values.
deriveUnit:  gets the destination units.
createRenderedImage:  the actual call to ImageN.createNS.
Since:
2.2
Author:
Martin Desruisseaux (IRD), Simone Giannecchini
See Also:

  • Field Details

    • RENDERED_MODE

      protected static final String RENDERED_MODE
      The rendered mode for ImageN operation.
      See Also:

    • operation

      protected final OperationDescriptor operation
      The JAI's operation descriptor.

  • Constructor Details

    • OperationJAI

      public OperationJAI(String operation) throws OperationNotFoundException
      Constructs a grid coverage operation from a ImageN operation name. This convenience constructor fetch the OperationDescriptor from the specified operation name using the default JAI instance.
      Parameters:
      operation - ImageN operation name
      Throws:
      OperationNotFoundException - if no ImageN descriptor was found for the given name.

    • OperationJAI

      public OperationJAI(OperationDescriptor operation)
      Constructs a grid coverage operation backed by a ImageN operation. The operation descriptor must supports the "rendered" mode (which is the case for most ImageN operations).
      Parameters:
      operation - The ImageN operation descriptor.

    • OperationJAI

      public OperationJAI(String operationName, OperationDescriptor operation)
      Constructs a grid coverage operation backed by a ImageN operation. The operation descriptor must supports the "rendered" mode (which is the case for most ImageN operations).
      Parameters:
      operationName - ImageN operation name
      operation - The ImageN operation descriptor.

    • OperationJAI

      protected OperationJAI(OperationDescriptor operation, ParameterDescriptorGroup descriptor)
      Constructs a grid coverage operation backed by a ImageN operation. The operation descriptor must supports the "rendered" mode (which is the case for most ImageN operations).
      Parameters:
      operation - The ImageN operation descriptor.
      descriptor - The OGC parameters descriptor.

  • Method Details

    • getOperationDescriptor

      protected static OperationDescriptor getOperationDescriptor(String name) throws OperationNotFoundException
      Returns the operation descriptor for the specified ImageN operation name. This method uses the default JAI instance and looks for the "rendered" mode.
      Parameters:
      name - The operation name.
      Returns:
      The operation descriptor for the given name.
      Throws:
      OperationNotFoundException - if no ImageN descriptor was found for the given name.
      Since:
      2.4

    • prepareParameters

      protected ParameterBlockImageN prepareParameters(ParameterValueGroup parameters)
      Copies parameter values from the specified ParameterValueGroup to the ParameterBlockImageN, except the sources.

      Note: it would be possible to use ImagingParameters.parameters directly in some occasions. However, we perform an unconditional copy instead because some operations may change the values.

      Parameters:
      parameters - The ParameterValueGroup to be copied.
      Returns:
      A copy of the provided ParameterValueGroup as a ImageN block.
      Since:
      2.4

    • doOperation

      public Coverage doOperation(ParameterValueGroup parameters, Hints hints) throws CoverageProcessingException
      Applies a process operation to a grid coverage. The default implementation performs the following steps:
      1. Ensures that every sources GridCoverage2Ds use the same coordinate reference system (at least for the two-dimensional part) with the same gridToCRS relationship.
      2. Invokes deriveGridCoverage(org.geotools.coverage.grid.GridCoverage2D[], org.geotools.coverage.processing.OperationJAI.Parameters). The sources in the ParameterBlock are RenderedImage objects obtained from GridCoverage2D.getRenderedImage().
      3. If a changes from non-geophysics to geophysics view were performed at step 1, converts the result back to the original view using GridCoverage2D.geophysics(false).
      Specified by:
      doOperation in class AbstractOperation
      Parameters:
      parameters - List of name value pairs for the parameters required for the operation.
      hints - A set of rendering hints, or null if none.
      Returns:
      The result as a grid coverage.
      Throws:
      CoverageProcessingException - if the operation can't be applied.
      See Also:

    • resampleToCommonGeometry

      protected void resampleToCommonGeometry(GridCoverage2D[] sources, CoordinateReferenceSystem crs2D, MathTransform2D gridToCrs2D, Hints hints) throws InvalidGridGeometryException, CannotReprojectException
      Resamples all sources grid coverages to the same two-dimensional geometry before to apply the operation. This method is invoked automatically by the doOperation method. Only the two-dimensional part is reprojected (usually the spatial component of a CRS). Extra dimension (if any) are left unchanged. Extra dimensions are typically time axis or depth. Note that extra dimensions are not forced to a common geometry; only the two dimensions that apply to a PlanarImage are. This is because the extra dimensions don't need to be compatible for all operations. For example if a source image is a slice in a time series, a second source image could be a slice in the frequency representation of this time series.

      Subclasses should override this method if they want to specify target grid geometry and coordinate reference system different than the default ones. For example if a subclass wants to force all images to be referenced in a WGS 84 CRS, then it may overrides this method as below: 

       protected void resampleToCommonGeometry(...) {
    crs2D = DefaultGeographicCRS.WGS84;
    super.resampleToCommonGeometry(sources, crs2D, gridToCrs2D, hints);
 }
      Parameters:
      sources - The source grid coverages to resample. This array is updated in-place as needed (for example if a grid coverage is replaced by a projected one).
      crs2D - The target coordinate reference system to use, or null for a default one.
      gridToCrs2D - The target "grid to coordinate reference system" transform, or null for a default one.
      hints - The rendering hints, or null if none.
      Throws:
      InvalidGridGeometryException - if a source coverage has an unsupported grid geometry.
      CannotReprojectException - if a grid coverage can't be resampled for some other reason.

    • deriveGridCoverage

      protected GridCoverage2D deriveGridCoverage(GridCoverage2D[] sources, OperationJAI.Parameters parameters)
      Applies a ImageN operation to a grid coverage. This method is invoked automatically by doOperation(org.geotools.api.parameter.ParameterValueGroup, org.geotools.util.factory.Hints). The default implementation performs the following steps:
      Parameters:
      sources - The source coverages.
      parameters - Parameters, rendering hints and coordinate reference system to use.
      Returns:
      The result as a grid coverage.
      See Also:

    • getProperties

      protected Map<String,?> getProperties(RenderedImage data, CoordinateReferenceSystem crs, InternationalString name, MathTransform gridToCRS, GridCoverage2D[] sources, OperationJAI.Parameters parameters)
      Prepares the properties to be given to the coverage created by the deriveGridCoverage method. The default implementation returns null.
      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.
      gridToCRS - 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.
      Since:
      2.4

    • getQuantitative

      protected static int getQuantitative(Category[] categories)
      Returns the index of the quantitative category, providing that there is one and only one quantitative category. If categories contains 0, 2 or more quantitative category, then this method returns -1.
      Parameters:
      categories - The categories to test.
      Returns:
      The index of the quantitative category, or -1 if none can be choosen.
      Since:
      2.4

    • deriveSampleDimension

      protected GridSampleDimension[] deriveSampleDimension(GridSampleDimension[][] bandLists, OperationJAI.Parameters parameters)
      Returns the sample dimensions for the target grid coverage. This method is invoked automatically by deriveGridCoverage with a bandLists argument initialized as below:

      • The bandLists array length is equals to the number of source coverages.
      • The bandLists[i] array length is equals to the number of sample dimensions in the source coverage i.
      • The sample dimension for a band at index band in the source at index source is bandLists[source][band].

      This method shall returns an array with a length equals to the number of bands in the target image. If the sample dimensions can't be determined, then this method is allowed to returns null.

      The default implementation iterates among all bands and invokes the deriveCategory and deriveUnit methods for each of them. Subclasses should override this method if they know a more accurate algorithm for determining sample dimensions.

      Parameters:
      bandLists - The set of sample dimensions for each source GridCoverage2Ds.
      parameters - Parameters, rendering hints and coordinate reference system to use.
      Returns:
      The sample dimensions for each band in the destination image, or null if unknown.
      See Also:

    • deriveCategory

      protected Category deriveCategory(Category[] categories, OperationJAI.Parameters parameters)
      Returns the quantitative category for a single sample dimension in the target grid coverage. This method is invoked automatically by the deriveSampleDimension method for each band in the target image. The default implementation creates a default category from the target range of values returned by deriveRange.
      Parameters:
      categories - The quantitative categories from every sources. For unary operations like, this array has a length of 1. For binary operations like "add" and "multiply", this array has a length of 2.
      parameters - Parameters, rendering hints and coordinate reference system to use.
      Returns:
      The quantitative category to use in the destination image, or null if unknown.

    • deriveRange

      protected NumberRange<? extends Number> deriveRange(NumberRange<? extends Number>[] ranges, OperationJAI.Parameters parameters)
      Returns the range of value for a single sample dimension in the target grid coverage. This method is invoked automatically by the deriveCategory method for each band in the target image. Subclasses should override this method in order to compute the target range of values. For example, the "add" operation may implements this method as below: 
       double min = ranges[0].getMinimum() + ranges[1].getMinimum();
 double max = ranges[0}.getMaximum() + ranges[1}.getMaximum();
 return new NumberRange(min, max);
      Parameters:
      ranges - The range of values from every sources. For unary operations this array has a length of 1. For binary operations like "add" and "multiply", this array has a length of 2.
      parameters - Parameters, rendering hints and coordinate reference system to use.
      Returns:
      The range of values to use in the destination image, or null if unknow.

    • deriveUnit

      protected Unit<?> deriveUnit(Unit<?>[] units, OperationJAI.Parameters parameters)
      Returns the unit of data for a single sample dimension in the target grid coverage. This method is invoked automatically by the deriveSampleDimension method for each band in the target image. Subclasses should override this method in order to compute the target units from the source units. For example a "multiply" operation may implement this method as below: 
       if (units[0]!=null && units[1]!=null) {
     return units[0].multiply(units[1]);
 } else {
     return super.deriveUnit(units, cs, parameters);
 }
      Parameters:
      units - The units from every sources. For unary operations this array has a length of 1. For binary operations like "add" and "multiply", this array has a length of 2.
      parameters - Parameters, rendering hints and coordinate reference system to use.
      Returns:
      The unit of data in the destination image, or null if unknow.

    • deriveName

      protected InternationalString deriveName(GridCoverage2D[] sources, int primarySourceIndex, OperationJAI.Parameters parameters)
      Returns a name for the target grid coverage based on the given sources. This method is invoked once by the deriveGridCoverage method. The default implementation returns the operation name followed by the source name between parenthesis, for example "Add(Sea Surface Temperature)".
      Parameters:
      sources - The sources grid coverage.
      primarySourceIndex - The index of what seems to be the primary source, or -1 if none of unknown.
      parameters - Parameters, rendering hints and coordinate reference system to use.
      Returns:
      A name for the target grid coverage.

    • createRenderedImage

      protected RenderedImage createRenderedImage(ParameterBlockImageN parameters, RenderingHints hints)
      Applies the ImageN operation. The operation name can be fetch from operation. The ImageN instance to use can be fetch from getJAI(java.awt.RenderingHints). The default implementation returns the following: 
       getJAI(hints).createNS(operation.getName(), parameters, hints)
      Subclasses may override this method in order to invokes a different ImageN operation according the parameters.
      Parameters:
      parameters - The parameters to be given to ImageN.
      hints - The rendering hints to be given to ImageN.
      Returns:
      The result of ImageN operation using the given parameters and hints.

    • getJAI

      public static final ImageN getJAI(RenderingHints hints)
      Returns the JAI instance to use for operations on RenderedImage. If no ImageN instance is defined for the Hints.JAI_INSTANCE key, then the default instance is returned.
      Parameters:
      hints - The rendering hints, or null if none.
      Returns:
      The ImageN instance to use (never null).

    • equals

      public boolean equals(Object object)
      Compares the specified object with this operation for equality.
      Overrides:
      equals in class AbstractOperation
      Parameters:
      object - The object to compare with this operation.
      Returns:
      true if the given object is equals to this operation.

    • hashCode

      public int hashCode()
      Description copied from class: AbstractOperation
      Returns a hash value for this operation. This value need not remain consistent between different implementations of the same class.
      Overrides:
      hashCode in class AbstractOperation

    • handleJAIEXTParams

      protected void handleJAIEXTParams(ParameterBlockImageN parameters, ParameterValueGroup parameters2)
      Extension point for adding to the ImageN ParameterBlockImageN object the parameters defined in the ParameterValueGroup, which can be read by the JAI-EXT operations.

      Notice that if you are using JAI, the new parameters will not be accepted by the ParameterBlockImageN instance.

      Parameters:
      parameters - ParameterBlockImageN instance used by the current JAI-EXT/JAI operation
      parameters2 - ParameterValueGroup instance containing input operation parameters

    • handleROINoDataProperties

      protected static Map<String,Object> handleROINoDataProperties(Map<String,Object> properties, ParameterBlockImageN parameters, GridCoverage2D sourceCoverage, String operationName, int roiIndex, int noDataIndex, int backgroundIndex)
      This method can be used for creating a property Map to set to the new coverage generated by the current operation. Internally the method will search for ROI and NoData parameters set for the operation and will report them as coverage properties
      Returns:
      A Map containing all the coverage properties and also ROI and NoData if present

    • handleROINoDataInternal

      protected static void handleROINoDataInternal(ParameterBlockImageN parameters, GridCoverage2D sourceCoverage, String operationName, int roiIndex, int noDataIndex)
      This method can be used for merging input coverage properties (ROI and NoData) with the ones provided as input in the ParameterBlock instance. If a ROI instance is already present as a coverage property, it will be intersected with an eventual ROI object defined as a parameter inside the ParameterBlock. If no NoData Range is defined in the parameters but is defined as coverage property, it will be set in the input ParameterBlock

    • extractSources

      protected void extractSources(ParameterValueGroup parameters, Collection<GridCoverage2D> sources, String[] sourceNames) throws ParameterNotFoundException, InvalidParameterValueException
      Extraction of the sources from the parameter called SOURCES. The sources are stored inside a List.
      Throws:
      ParameterNotFoundException
      InvalidParameterValueException