001/**
002 * Copyright (c) 2011, The University of Southampton and the individual contributors.
003 * All rights reserved.
004 *
005 * Redistribution and use in source and binary forms, with or without modification,
006 * are permitted provided that the following conditions are met:
007 *
008 *   *  Redistributions of source code must retain the above copyright notice,
009 *      this list of conditions and the following disclaimer.
010 *
011 *   *  Redistributions in binary form must reproduce the above copyright notice,
012 *      this list of conditions and the following disclaimer in the documentation
013 *      and/or other materials provided with the distribution.
014 *
015 *   *  Neither the name of the University of Southampton nor the names of its
016 *      contributors may be used to endorse or promote products derived from this
017 *      software without specific prior written permission.
018 *
019 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
020 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
021 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
022 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
023 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
024 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
025 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
026 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
027 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
028 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
029 */
030package org.openimaj.image.pixel.statistics;
031
032import org.openimaj.image.FImage;
033import org.openimaj.image.MBFImage;
034import org.openimaj.math.statistics.distribution.MultidimensionalHistogram;
035
036
037/**
038 * An array of multidimensional histograms calculated from image pixels using a mask
039 * (assumes image is in 0-1 range)
040 * 
041 * @author Jonathon Hare
042 *
043 */
044public class MaskingBlockHistogramModel extends BlockHistogramModel {
045        private static final long serialVersionUID = 1L;
046        private FImage mask;
047        
048        /**
049         * Construct with the given parameters
050         * @param mask the mask image
051         * @param blocks_x the number of blocks in the x-direction
052         * @param blocks_y the number of blocks in the y-direction
053         * @param nbins the number of bins in each dimension for the histograms
054         */
055        public MaskingBlockHistogramModel(FImage mask, int blocks_x, int blocks_y, int... nbins) {
056                super(blocks_x, blocks_y, nbins);
057                
058                this.mask = mask;
059        }
060        
061        @Override
062        protected void accum(MBFImage im, int bx, int by) {
063                assert (im.numBands() == ndims);
064
065                MultidimensionalHistogram histogram = histograms[by][bx];
066                int height = im.getHeight();
067                int width = im.getWidth();
068                
069                int cols_per_block = width / blocks_x;          
070                int startx = bx*cols_per_block;
071                int stopx = (1+bx)*cols_per_block;
072
073                int rows_per_block = height / blocks_y;
074                int starty = by*rows_per_block;
075                int stopy = (1+by)*rows_per_block;
076                
077                if (stopx >= width) stopx = width;
078                if (stopy >= height) stopy = height;
079                
080                for (int y=starty; y<stopy; y++) {
081                        for (int x=startx; x<stopx; x++) {
082                                if (mask.pixels[y][x] != 1)
083                                        continue;
084                                
085                                int [] bins = new int[ndims];
086                                
087                                for (int i=0; i<ndims; i++) {
088                                        bins[i] = (int)(im.getBand(i).pixels[y][x] * (histogram.nbins[i]));
089                                        if (bins[i] >= histogram.nbins[i]) bins[i] = histogram.nbins[i] - 1;
090                                }
091                                
092                                int bin = 0;
093                                for (int i=0; i<ndims; i++) {
094                                        int f = 1;
095                                        for (int j=0; j<i; j++)
096                                                f *= histogram.nbins[j];
097                                        
098                                        bin += f * bins[i];
099                                }
100                                
101                                histogram.values[bin]++;
102                        }
103                }
104        }
105}