Class BandCombineOp

java.lang.Object
java.awt.image.BandCombineOp
All Implemented Interfaces:
RasterOp
public class BandCombineOp extends Object implements RasterOp
This class performs an arbitrary linear combination of the bands in a Raster, using a specified matrix.

The width of the matrix must be equal to the number of bands in the source Raster, optionally plus one. If there is one more column in the matrix than the number of bands, there is an implied 1 at the end of the vector of band samples representing a pixel. The height of the matrix must be equal to the number of bands in the destination.

For example, a 3-banded Raster might have the following transformation applied to each pixel in order to invert the second band of the Raster. 

  [ 1.0   0.0   0.0    0.0  ]     [ b1 ]
  [ 0.0  -1.0   0.0  255.0  ]  x  [ b2 ]
  [ 0.0   0.0   1.0    0.0  ]     [ b3 ]
                                  [ 1 ]

Note that the source and destination can be the same object.

  • Constructor Summary

    Constructors
    Constructor
    Description
    BandCombineOp(float[][] matrix, RenderingHints hints)
    Constructs a BandCombineOp with the specified matrix.

  • Method Summary

    Modifier and Type
    Method
    Description
    WritableRaster
    createCompatibleDestRaster(Raster src)
    Creates a zeroed destination Raster with the correct size and number of bands.
    WritableRaster
    filter(Raster src, WritableRaster dst)
    Transforms the Raster using the matrix specified in the constructor.
    final Rectangle2D
    getBounds2D(Raster src)
    Returns the bounding box of the transformed destination.
    final float[][]
    getMatrix()
    Returns a copy of the linear combination matrix.
    final Point2D
    getPoint2D(Point2D srcPt, Point2D dstPt)
    Returns the location of the corresponding destination point given a point in the source Raster.
    final RenderingHints
    getRenderingHints()
    Returns the rendering hints for this operation.

    Methods declared in class Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
    Modifier and Type
    Method
    Description
    protected Object
    clone()
    Answers a new instance of the same class as the receiver, whose slots have been filled in with the values in the slots of the receiver.
    boolean
    equals(Object o)
    Compares the argument to the receiver, and answers true if they represent the same object using a class specific comparison.
    protected void
    finalize()
    Deprecated, for removal: This API element is subject to removal in a future version.
    May cause performance issues, deadlocks and hangs.
    final Class<? extends Object>
    getClass()
    Answers the unique instance of java.lang.Class which represents the class of the receiver.
    int
    hashCode()
    Answers an integer hash code for the receiver.
    final void
    notify()
    Causes one thread which is waiting on the receiver to be made ready to run.
    final void
    notifyAll()
    Causes all threads which are waiting on the receiver to be made ready to run.
    String
    toString()
    Answers a string containing a concise, human-readable description of the receiver.
    final void
    wait()
    Causes the thread which sent this message to be made not ready to run pending some change in the receiver (as indicated by notify or notifyAll).
    final void
    wait(long time)
    Causes the thread which sent this message to be made not ready to run either pending some change in the receiver (as indicated by notify or notifyAll) or the expiration of the timeout.
    final void
    wait(long time, int frac)
    Causes the thread which sent this message to be made not ready to run either pending some change in the receiver (as indicated by notify or notifyAll) or the expiration of the timeout.

  • Constructor Details

    • BandCombineOp

      public BandCombineOp(float[][] matrix, RenderingHints hints)
      Constructs a BandCombineOp with the specified matrix. The width of the matrix must be equal to the number of bands in the source Raster, optionally plus one. If there is one more column in the matrix than the number of bands, there is an implied 1 at the end of the vector of band samples representing a pixel. The height of the matrix must be equal to the number of bands in the destination.

      The first subscript is the row index and the second is the column index. This operation uses none of the currently defined rendering hints; the RenderingHints argument can be null.

      Parameters:
      matrix - The matrix to use for the band combine operation.
      hints - The RenderingHints object for this operation. Not currently used so it can be null.

  • Method Details

    • getMatrix

      public final float[][] getMatrix()
      Returns a copy of the linear combination matrix.
      Returns:
      The matrix associated with this band combine operation.

    • filter

      public WritableRaster filter(Raster src, WritableRaster dst)
      Transforms the Raster using the matrix specified in the constructor. An IllegalArgumentException may be thrown if the number of bands in the source or destination is incompatible with the matrix. See the class comments for more details.

      If the destination is null, it will be created with a number of bands equalling the number of rows in the matrix. No exception is thrown if the operation causes a data overflow.

      Specified by:
      filter in interface RasterOp
      Parameters:
      src - The Raster to be filtered.
      dst - The Raster in which to store the results of the filter operation.
      Returns:
      The filtered Raster.
      Throws:
      IllegalArgumentException - If the number of bands in the source or destination is incompatible with the matrix.

    • getBounds2D

      public final Rectangle2D getBounds2D(Raster src)
      Returns the bounding box of the transformed destination. Since this is not a geometric operation, the bounding box is the same for the source and destination. An IllegalArgumentException may be thrown if the number of bands in the source is incompatible with the matrix. See the class comments for more details.
      Specified by:
      getBounds2D in interface RasterOp
      Parameters:
      src - The Raster to be filtered.
      Returns:
      The Rectangle2D representing the destination image's bounding box.
      Throws:
      IllegalArgumentException - If the number of bands in the source is incompatible with the matrix.

    • createCompatibleDestRaster

      public WritableRaster createCompatibleDestRaster(Raster src)
      Creates a zeroed destination Raster with the correct size and number of bands. An IllegalArgumentException may be thrown if the number of bands in the source is incompatible with the matrix. See the class comments for more details.
      Specified by:
      createCompatibleDestRaster in interface RasterOp
      Parameters:
      src - The Raster to be filtered.
      Returns:
      The zeroed destination Raster.

    • getPoint2D

      public final Point2D getPoint2D(Point2D srcPt, Point2D dstPt)
      Returns the location of the corresponding destination point given a point in the source Raster. If dstPt is specified, it is used to hold the return value. Since this is not a geometric operation, the point returned is the same as the specified srcPt.
      Specified by:
      getPoint2D in interface RasterOp
      Parameters:
      srcPt - The Point2D that represents the point in the source Raster
      dstPt - The Point2D in which to store the result.
      Returns:
      The Point2D in the destination image that corresponds to the specified point in the source image.

    • getRenderingHints

      public final RenderingHints getRenderingHints()
      Returns the rendering hints for this operation.
      Specified by:
      getRenderingHints in interface RasterOp
      Returns:
      The RenderingHints object associated with this operation. Returns null if no hints have been set.