public class LookupOp extends Object implements BufferedImageOp, RasterOp
For Rasters, the lookup operates on bands. The number of lookup arrays may be one, in which case the same array is applied to all bands, or it must equal the number of Source Raster bands.
For BufferedImages, the lookup operates on color and alpha components. The number of lookup arrays may be one, in which case the same array is applied to all color (but not alpha) components. Otherwise, the number of lookup arrays may equal the number of Source color components, in which case no lookup of the alpha component (if present) is performed. If neither of these cases apply, the number of lookup arrays must equal the number of Source color components plus alpha components, in which case lookup is performed for all color and alpha components. This allows non-uniform rescaling of multi-band BufferedImages.
BufferedImage sources with premultiplied alpha data are treated in the same manner as non-premultiplied images for purposes of the lookup. That is, the lookup is done per band on the raw data of the BufferedImage source without regard to whether the data is premultiplied. If a color conversion is required to the destination ColorModel, the premultiplied state of both source and destination will be taken into account for this step.
Images with an IndexColorModel cannot be used.
If a RenderingHints object is specified in the constructor, the color rendering hint and the dithering hint may be used when color conversion is required.
This class allows the Source to be the same as the Destination.
| Constructor and Description | 
|---|
| LookupOp(LookupTable lookup,
        RenderingHints hints)Constructs a  LookupOpobject given the lookup
 table and aRenderingHintsobject, which might
 benull. | 
| Modifier and Type | Method and Description | 
|---|---|
| BufferedImage | createCompatibleDestImage(BufferedImage src,
                         ColorModel destCM)Creates a zeroed destination image with the correct size and number of
 bands. | 
| WritableRaster | createCompatibleDestRaster(Raster src)Creates a zeroed-destination  Rasterwith the
 correct size and number of bands, given this source. | 
| BufferedImage | filter(BufferedImage src,
      BufferedImage dst)Performs a lookup operation on a  BufferedImage. | 
| WritableRaster | filter(Raster src,
      WritableRaster dst)Performs a lookup operation on a  Raster. | 
| Rectangle2D | getBounds2D(BufferedImage src)Returns the bounding box of the filtered destination image. | 
| Rectangle2D | getBounds2D(Raster src)Returns the bounding box of the filtered destination Raster. | 
| Point2D | getPoint2D(Point2D srcPt,
          Point2D dstPt)Returns the location of the destination point given a
 point in the source. | 
| RenderingHints | getRenderingHints()Returns the rendering hints for this op. | 
| LookupTable | getTable()Returns the  LookupTable. | 
public LookupOp(LookupTable lookup, RenderingHints hints)
LookupOp object given the lookup
 table and a RenderingHints object, which might
 be null.lookup - the specified LookupTablehints - the specified RenderingHints,
        or nullpublic final LookupTable getTable()
LookupTable.LookupTable of this
         LookupOp.public final BufferedImage filter(BufferedImage src, BufferedImage dst)
BufferedImage.
 If the color model in the source image is not the same as that
 in the destination image, the pixels will be converted
 in the destination.  If the destination image is null,
 a BufferedImage will be created with an appropriate
 ColorModel.  An IllegalArgumentException
 might be thrown if the number of arrays in the
 LookupTable does not meet the restrictions
 stated in the class comment above, or if the source image
 has an IndexColorModel.filter in interface BufferedImageOpsrc - the BufferedImage to be filtereddst - the BufferedImage in which to
            store the results of the filter operationBufferedImage.IllegalArgumentException - if the number of arrays in the
         LookupTable does not meet the restrictions
         described in the class comments, or if the source image
         has an IndexColorModel.public final WritableRaster filter(Raster src, WritableRaster dst)
Raster.
 If the destination Raster is null,
 a new Raster will be created.
 The IllegalArgumentException might be thrown
 if the source Raster and the destination
 Raster do not have the same
 number of bands or if the number of arrays in the
 LookupTable does not meet the
 restrictions stated in the class comment above.filter in interface RasterOpsrc - the source Raster to filterdst - the destination WritableRaster for the
            filtered srcWritableRaster.IllegalArgumentException - if the source and destinations
         rasters do not have the same number of bands, or the
         number of arrays in the LookupTable does
         not meet the restrictions described in the class comments.public final Rectangle2D getBounds2D(BufferedImage src)
getBounds2D in interface BufferedImageOpsrc - the BufferedImage to be filteredpublic final Rectangle2D getBounds2D(Raster src)
getBounds2D in interface RasterOpsrc - the Raster to be filteredRaster.public BufferedImage createCompatibleDestImage(BufferedImage src, ColorModel destCM)
null, an appropriate
 ColorModel will be used.createCompatibleDestImage in interface BufferedImageOpsrc - Source image for the filter operation.destCM - the destination's ColorModel, which
                  can be null.BufferedImage.public WritableRaster createCompatibleDestRaster(Raster src)
Raster with the
 correct size and number of bands, given this source.createCompatibleDestRaster in interface RasterOpsrc - the Raster to be transformedRaster.public final Point2D getPoint2D(Point2D srcPt, Point2D dstPt)
dstPt is not
 null, it will be used to hold the return value.
 Since this is not a geometric operation, the srcPt
 will equal the dstPt.getPoint2D in interface BufferedImageOpgetPoint2D in interface RasterOpsrcPt - a Point2D that represents a point
        in the source imagedstPt - a Point2Dthat represents the location
        in the destinationPoint2D in the destination that
         corresponds to the specified point in the source.public final RenderingHints getRenderingHints()
getRenderingHints in interface BufferedImageOpgetRenderingHints in interface RasterOpRenderingHints object associated
         with this op. Submit a bug or feature 
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