001/*
002Copyright 2006 Jerry Huxtable
003
004Licensed under the Apache License, Version 2.0 (the "License");
005you may not use this file except in compliance with the License.
006You may obtain a copy of the License at
007
008   http://www.apache.org/licenses/LICENSE-2.0
009
010Unless required by applicable law or agreed to in writing, software
011distributed under the License is distributed on an "AS IS" BASIS,
012WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013See the License for the specific language governing permissions and
014limitations under the License.
015*/
016
017package com.jhlabs.image;
018
019import java.awt.*;
020import java.awt.image.*;
021
022/**
023 * A filter which uses the brightness of each pixel to lookup a color from a colormap. 
024 */
025public class LookupFilter extends PointFilter {
026        
027        private Colormap colormap = new Gradient();
028        
029        /**
030     * Construct a LookupFilter.
031     */
032    public LookupFilter() {
033                canFilterIndexColorModel = true;
034        }
035
036        /**
037     * Construct a LookupFilter.
038     * @param colormap the color map
039     */
040        public LookupFilter(Colormap colormap) {
041                canFilterIndexColorModel = true;
042                this.colormap = colormap;
043        }
044
045    /**
046     * Set the colormap to be used for the filter.
047     * @param colormap the colormap
048     * @see #getColormap
049     */
050        public void setColormap(Colormap colormap) {
051                this.colormap = colormap;
052        }
053
054    /**
055     * Get the colormap to be used for the filter.
056     * @return the colormap
057     * @see #setColormap
058     */
059        public Colormap getColormap() {
060                return colormap;
061        }
062
063        public int filterRGB(int x, int y, int rgb) {
064//              int a = rgb & 0xff000000;
065                int r = (rgb >> 16) & 0xff;
066                int g = (rgb >> 8) & 0xff;
067                int b = rgb & 0xff;
068                rgb = (r + g + b) / 3;
069                return colormap.getColor(rgb/255.0f);
070        }
071
072        public String toString() {
073                return "Colors/Lookup...";
074        }
075
076}
077
078