Module java.desktop
Package java.awt.image

Class LookupTable

java.lang.Object
java.awt.image.LookupTable
Direct Known Subclasses:
ByteLookupTable, ShortLookupTable
public abstract class LookupTable
extends Object
This abstract class defines a lookup table object. ByteLookupTable and ShortLookupTable are subclasses, which contain byte and short data, respectively. A lookup table contains data arrays for one or more bands (or components) of an image (for example, separate arrays for R, G, and B), and it contains an offset which will be subtracted from the input values before indexing into the arrays. This allows an array smaller than the native data size to be provided for a constrained input. If there is only one array in the lookup table, it will be applied to all bands. All arrays must be the same size.
See Also:
ByteLookupTable, ShortLookupTable, LookupOp

  • Constructor Summary

    Constructors 
    Modifier Constructor Description
    protected LookupTable​(int offset, int numComponents)
    Constructs a new LookupTable from the number of components and an offset into the lookup table.

  • Method Summary

    Modifier and Type Method Description
    int getNumComponents()
    Returns the number of components in the lookup table.
    int getOffset()
    Returns the offset.
    abstract int[] lookupPixel​(int[] src, int[] dest)
    Returns an int array of components for one pixel.

    Methods declared in class java.lang.Object

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

  • Constructor Details

    • LookupTable

      protected LookupTable​(int offset, int numComponents)
      Constructs a new LookupTable from the number of components and an offset into the lookup table.
      Parameters:
      offset - the offset to subtract from input values before indexing into the data arrays for this LookupTable
      numComponents - the number of data arrays in this LookupTable
      Throws:
      IllegalArgumentException - if offset is less than 0 or if numComponents is less than 1

  • Method Details

    • getNumComponents

      public int getNumComponents()
      Returns the number of components in the lookup table.
      Returns:
      the number of components in this LookupTable.

    • getOffset

      public int getOffset()
      Returns the offset.
      Returns:
      the offset of this LookupTable.

    • lookupPixel

      public abstract int[] lookupPixel​(int[] src, int[] dest)
      Returns an int array of components for one pixel. The dest array contains the result of the lookup and is returned. If dest is null, a new array is allocated. The source and destination can be equal.
      Parameters:
      src - the source array of components of one pixel
      dest - the destination array of components for one pixel, translated with this LookupTable
      Returns:
      an int array of components for one pixel.