/**
 * Copyright (c) 2011, The University of Southampton and the individual contributors.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without modification,
 * are permitted provided that the following conditions are met:
 *
 *   *  Redistributions of source code must retain the above copyright notice,
 *      this list of conditions and the following disclaimer.
 *
 *   *  Redistributions in binary form must reproduce the above copyright notice,
 *      this list of conditions and the following disclaimer in the documentation
 *      and/or other materials provided with the distribution.
 *
 *   *  Neither the name of the University of Southampton nor the names of its
 *      contributors may be used to endorse or promote products derived from this
 *      software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
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 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package org.openimaj.image.feature.global;

import gnu.trove.map.hash.TObjectFloatHashMap;
import gnu.trove.procedure.TObjectFloatProcedure;

import org.openimaj.citation.annotation.Reference;
import org.openimaj.citation.annotation.ReferenceType;
import org.openimaj.feature.DoubleFV;
import org.openimaj.feature.FeatureVectorProvider;
import org.openimaj.image.FImage;
import org.openimaj.image.MBFImage;
import org.openimaj.image.analyser.ImageAnalyser;
import org.openimaj.image.pixel.ConnectedComponent;
import org.openimaj.image.processor.connectedcomponent.render.BoundingBoxRenderer;
import org.openimaj.image.saliency.AchantaSaliency;
import org.openimaj.image.saliency.YehSaliency;
import org.openimaj.image.segmentation.FelzenszwalbHuttenlocherSegmenter;
import org.openimaj.util.array.ArrayUtils;

/**
 * Implementation of the region of interest based image simplicity measure
 * described by Yeh et al.
 * <p>
 * Basically returns the proportion of the image that can be considered
 * interesting.
 *
 * @author Jonathon Hare (jsh2@ecs.soton.ac.uk)
 */
@Reference(
                type = ReferenceType.Inproceedings,
                author = { "Che-Hua Yeh", "Yuan-Chen Ho", "Brian A. Barsky", "Ming Ouhyoung" },
                title = "Personalized Photograph Ranking and Selection System",
                year = "2010",
                booktitle = "Proceedings of ACM Multimedia",
                pages = { "211", "220" },
                month = "October",
                customData = { "location", "Florence, Italy" })
public class ROIProportion implements ImageAnalyser<MBFImage>, FeatureVectorProvider<DoubleFV> {
        protected YehSaliency saliencyGenerator;
        protected float alpha = 0.67f;

        protected double roiProportion;

        /**
         * Construct with the default values
         */
        public ROIProportion() {
                saliencyGenerator = new YehSaliency();
        }

        /**
         * Construct with the given alpha value, but use the defaults for the
         * {@link YehSaliency} estimator.
         *
         * @param alpha
         *            the alpha value for determining the threshold
         */
        public ROIProportion(float alpha) {
                this();
                this.alpha = alpha;
        }

        /**
         * Construct with the given parameters.
         *
         * @param saliencySigma
         *            smoothing for the {@link AchantaSaliency} class
         * @param segmenterSigma
         *            smoothing for {@link FelzenszwalbHuttenlocherSegmenter}.
         * @param k
         *            k value for {@link FelzenszwalbHuttenlocherSegmenter}.
         * @param minSize
         *            minimum region size for
         *            {@link FelzenszwalbHuttenlocherSegmenter}.
         * @param alpha
         *            the alpha value for determining the threshold
         */
        public ROIProportion(float saliencySigma, float segmenterSigma, float k, int minSize, float alpha) {
                saliencyGenerator = new YehSaliency(saliencySigma, segmenterSigma, k, minSize);
                this.alpha = alpha;
        }

        @Override
        public DoubleFV getFeatureVector() {
                return new DoubleFV(new double[] { roiProportion });
        }

        /*
         * (non-Javadoc)
         *
         * @see
         * org.openimaj.image.analyser.ImageAnalyser#analyseImage(org.openimaj.image
         * .Image)
         */
        @Override
        public void analyseImage(MBFImage image) {
                image.analyseWith(saliencyGenerator);
                final TObjectFloatHashMap<ConnectedComponent> componentMap = saliencyGenerator.getSaliencyComponents();

                final float max = ArrayUtils.maxValue(componentMap.values());

                final FImage map = new FImage(image.getWidth(), image.getHeight());
                final float thresh = max * alpha;
                final BoundingBoxRenderer<Float> renderer = new BoundingBoxRenderer<Float>(map, 1F, true);

                componentMap.forEachEntry(new TObjectFloatProcedure<ConnectedComponent>() {
                        @Override
                        public boolean execute(ConnectedComponent cc, float sal) {
                                if (sal >= thresh) { // note that this is reversed from the
                                        // paper, which doesn't seem to make
                                        // sense.
                                        renderer.process(cc);
                                }

                                return true;
                        }
                });

                roiProportion = 0;
                for (int y = 0; y < map.height; y++)
                        for (int x = 0; x < map.width; x++)
                                roiProportion += map.pixels[y][x];

                roiProportion /= (map.width * map.height); // smaller simplicity means
                // smaller ROI
        }
}