Module java.desktop
Package java.awt.image

Class 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.

    • Constructor Detail

      • 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 Detail

      • 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.