001/**
002 *
003 * Copyright (c) 2014, the Railo Company Ltd. All rights reserved.
004 *
005 * This library is free software; you can redistribute it and/or
006 * modify it under the terms of the GNU Lesser General Public
007 * License as published by the Free Software Foundation; either 
008 * version 2.1 of the License, or (at your option) any later version.
009 * 
010 * This library is distributed in the hope that it will be useful,
011 * but WITHOUT ANY WARRANTY; without even the implied warranty of
012 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
013 * Lesser General Public License for more details.
014 * 
015 * You should have received a copy of the GNU Lesser General Public 
016 * License along with this library.  If not, see <http://www.gnu.org/licenses/>.
017 * 
018 **/
019/*
020*
021
022Licensed under the Apache License, Version 2.0 (the "License");
023you may not use this file except in compliance with the License.
024You may obtain a copy of the License at
025
026   http://www.apache.org/licenses/LICENSE-2.0
027
028Unless required by applicable law or agreed to in writing, software
029distributed under the License is distributed on an "AS IS" BASIS,
030WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
031See the License for the specific language governing permissions and
032limitations under the License.
033*/
034
035package lucee.runtime.img.filter;import java.awt.image.BufferedImage;
036
037import lucee.runtime.engine.ThreadLocalPageContext;
038import lucee.runtime.exp.FunctionException;
039import lucee.runtime.exp.PageException;
040import lucee.runtime.img.ImageUtil;
041import lucee.runtime.type.KeyImpl;
042import lucee.runtime.type.Struct;
043import lucee.runtime.type.util.CollectionUtil;
044
045
046
047/**
048 * A filter which converts an image to grayscale using the NTSC brightness calculation.
049 */
050public class GrayscaleFilter extends PointFilter  implements DynFiltering {
051
052        public GrayscaleFilter() {
053                canFilterIndexColorModel = true;
054        }
055
056        public int filterRGB(int x, int y, int rgb) {
057                int a = rgb & 0xff000000;
058                int r = (rgb >> 16) & 0xff;
059                int g = (rgb >> 8) & 0xff;
060                int b = rgb & 0xff;
061//              rgb = (r + g + b) / 3;  // simple average
062                rgb = (r * 77 + g * 151 + b * 28) >> 8;   // NTSC luma
063                return a | (rgb << 16) | (rgb << 8) | rgb;
064        }
065
066        public String toString() {
067                return "Colors/Grayscale";
068        }
069
070        public BufferedImage filter(BufferedImage src, Struct parameters) throws PageException {BufferedImage dst=ImageUtil.createBufferedImage(src);
071                Object o;
072                if((o=parameters.removeEL(KeyImpl.init("Dimensions")))!=null){
073                        int[] dim=ImageFilterUtil.toDimensions(o,"Dimensions");
074                        setDimensions(dim[0],dim[1]);
075                }
076
077                // check for arguments not supported
078                if(parameters.size()>0) {
079                        throw new FunctionException(ThreadLocalPageContext.get(), "ImageFilter", 3, "parameters", "the parameter"+(parameters.size()>1?"s":"")+" ["+CollectionUtil.getKeyList(parameters,", ")+"] "+(parameters.size()>1?"are":"is")+" not allowed, only the following parameters are supported [Dimensions]");
080                }
081
082                return filter(src, dst);
083        }
084}
085
086