001    /*
002    *
003    
004    Licensed under the Apache License, Version 2.0 (the "License");
005    you may not use this file except in compliance with the License.
006    You may obtain a copy of the License at
007    
008       http://www.apache.org/licenses/LICENSE-2.0
009    
010    Unless required by applicable law or agreed to in writing, software
011    distributed under the License is distributed on an "AS IS" BASIS,
012    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013    See the License for the specific language governing permissions and
014    limitations under the License.
015    */
016    
017    package railo.runtime.img.filter;import java.awt.Rectangle;
018    import java.awt.image.BufferedImage;
019    
020    import railo.runtime.engine.ThreadLocalPageContext;
021    import railo.runtime.exp.FunctionException;
022    import railo.runtime.exp.PageException;
023    import railo.runtime.img.ImageUtil;
024    import railo.runtime.type.KeyImpl;
025    import railo.runtime.type.Struct;
026    import railo.runtime.type.util.CollectionUtil;
027    
028    /**
029     * Given a binary image, this filter performs binary erosion, setting all removed pixels to the given 'new' color.
030     */
031    public class ErodeFilter extends BinaryFilter  implements DynFiltering {
032    
033            private int threshold = 2;
034    
035            public ErodeFilter() {
036                    newColor = 0xffffffff;
037            }
038    
039            /**
040             * Set the threshold - the number of neighbouring pixels for dilation to occur.
041             * @param threshold the new threshold
042         * @see #getThreshold
043             */
044            public void setThreshold(int threshold) {
045                    this.threshold = threshold;
046            }
047            
048            /**
049             * Return the threshold - the number of neighbouring pixels for dilation to occur.
050             * @return the current threshold
051         * @see #setThreshold
052             */
053            public int getThreshold() {
054                    return threshold;
055            }
056            
057            protected int[] filterPixels( int width, int height, int[] inPixels, Rectangle transformedSpace ) {
058                    int[] outPixels = new int[width * height];
059    
060                    for (int i = 0; i < iterations; i++) {
061                            int index = 0;
062    
063                            if (i > 0) {
064                                    int[] t = inPixels;
065                                    inPixels = outPixels;
066                                    outPixels = t;
067                            }
068                            for (int y = 0; y < height; y++) {
069                                    for (int x = 0; x < width; x++) {
070                                            int pixel = inPixels[y*width+x];
071                                            if (blackFunction.isBlack(pixel)) {
072                                                    int neighbours = 0;
073    
074                                                    for (int dy = -1; dy <= 1; dy++) {
075                                                            int iy = y+dy;
076                                                            int ioffset;
077                                                            if (0 <= iy && iy < height) {
078                                                                    ioffset = iy*width;
079                                                                    for (int dx = -1; dx <= 1; dx++) {
080                                                                            int ix = x+dx;
081                                                                            if (!(dy == 0 && dx == 0) && 0 <= ix && ix < width) {
082                                                                                    int rgb = inPixels[ioffset+ix];
083                                                                                    if (!blackFunction.isBlack(rgb))
084                                                                                            neighbours++;
085                                                                            }
086                                                                    }
087                                                            }
088                                                    }
089                                                    
090                                                    if (neighbours >= threshold) {
091                                                            if (colormap != null)
092                                                                    pixel = colormap.getColor((float)i/iterations);
093                                                            else
094                                                                    pixel = newColor;
095                                                    }
096                                            }
097                                            outPixels[index++] = pixel;
098                                    }
099                            }
100                    }
101    
102                    return outPixels;
103            }
104    
105            public String toString() {
106                    return "Binary/Erode...";
107            }
108    
109            public BufferedImage filter(BufferedImage src, Struct parameters) throws PageException {BufferedImage dst=ImageUtil.createBufferedImage(src);
110                    Object o;
111                    if((o=parameters.removeEL(KeyImpl.init("Threshold")))!=null)setThreshold(ImageFilterUtil.toIntValue(o,"Threshold"));
112                    if((o=parameters.removeEL(KeyImpl.init("Iterations")))!=null)setIterations(ImageFilterUtil.toIntValue(o,"Iterations"));
113                    if((o=parameters.removeEL(KeyImpl.init("Colormap")))!=null)setColormap(ImageFilterUtil.toColormap(o,"Colormap"));
114                    if((o=parameters.removeEL(KeyImpl.init("NewColor")))!=null)setNewColor(ImageFilterUtil.toColorRGB(o,"NewColor"));
115                    
116                    // check for arguments not supported
117                    if(parameters.size()>0) {
118                            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 [Threshold, Iterations, Colormap, NewColor, BlackFunction]");
119                    }
120    
121                    return filter(src, dst);
122            }
123    }
124