/**
 * 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
 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package org.openimaj.image.connectedcomponent.proc;

import org.openimaj.feature.DoubleFV;
import org.openimaj.feature.FeatureVectorProvider;
import org.openimaj.image.MBFImage;
import org.openimaj.image.pixel.ConnectedComponent;
import org.openimaj.image.pixel.statistics.BasicDescriptiveStatisticsModel;
import org.openimaj.image.processor.connectedcomponent.ConnectedComponentProcessor;
import org.openimaj.util.array.ArrayUtils;

/**
 * Descriptors based on the first-order statistics
 * of the colour of pixel values in an image.
 * 
 * @author Jonathon Hare (jsh2@ecs.soton.ac.uk)
 */
public class ColourDescriptor implements ConnectedComponentProcessor, FeatureVectorProvider<DoubleFV> {
        /**
         * The different types of statistic available. This provides
         * a convenient way of getting a single statistic, as the {@link ColourDescriptor}
         * computes them all.
         * 
         * @author Jonathon Hare (jsh2@ecs.soton.ac.uk)
         *
         */
        public enum ColourDescriptorType {
                /**
                 * The mean colour.
                 * 
                 * @author Jonathon Hare (jsh2@ecs.soton.ac.uk)
                 */
                MEAN {
                        @Override
                        public DoubleFV getFeatureVector(ColourDescriptor desc) {
                                return new DoubleFV(desc.colmodel.mean);
                        }
                },
                /**
                 * The modal colour.
                 * 
                 * @author Jonathon Hare (jsh2@ecs.soton.ac.uk)
                 */
                MODE {
                        @Override
                        public DoubleFV getFeatureVector(ColourDescriptor desc) {
                                return new DoubleFV(desc.colmodel.mode);
                        }
                },
                /**
                 * The median colour.
                 * 
                 * @author Jonathon Hare (jsh2@ecs.soton.ac.uk)
                 */
                MEDIAN {
                        @Override
                        public DoubleFV getFeatureVector(ColourDescriptor desc) {
                                return new DoubleFV(desc.colmodel.median);
                        }
                },
                /**
                 * The range of the colours in the image.
                 * 
                 * @author Jonathon Hare (jsh2@ecs.soton.ac.uk)
                 */
                RANGE {
                        @Override
                        public DoubleFV getFeatureVector(ColourDescriptor desc) {
                                return new DoubleFV(desc.colmodel.range);
                        }
                },
                /**
                 * The variance of the colours in the image.
                 * 
                 * @author Jonathon Hare (jsh2@ecs.soton.ac.uk)
                 */
                VARIANCE {
                        @Override
                        public DoubleFV getFeatureVector(ColourDescriptor desc) {
                                return new DoubleFV(desc.colmodel.variance);
                        }
                };
                
                /**
                 * Extract the feature for the given descriptor.
                 * @param desc the descriptor to extract from
                 * @return the extracted feature.
                 */
                public abstract DoubleFV getFeatureVector(ColourDescriptor desc); 
        }
        
        protected MBFImage image;
        protected BasicDescriptiveStatisticsModel colmodel = new BasicDescriptiveStatisticsModel(3);
        
        /**
         * Construct with no image. The image must be set with 
         * {@link #setImage(MBFImage)} before processing. 
         */
        public ColourDescriptor() {
        }
        
        /**
         * Construct with the given image.
         * @param image the image to extract pixels from.
         */
        public ColourDescriptor(MBFImage image) {
                this.image = image;
        }
        
        @Override
        public void process(ConnectedComponent cc) {
                colmodel.estimateModel(cc.extractPixels1d(image));
        }

        /**
         * @return the extracted feature (containing all statistics) from the last call to {@link #process(ConnectedComponent)}.
         */
        public double[] getFeatureVectorArray() {
                return ArrayUtils.concatenate(
                                colmodel.mean,
                                colmodel.median,
                                colmodel.mode,
                                colmodel.range,
                                colmodel.variance
                );
        }

        /**
         * Set the image to extract pixels from.
         * @param img the image.
         */
        public void setImage(MBFImage img) {
                image = img;
        }
        
        /**
         * @return the extracted colour model from the last call to {@link #process(ConnectedComponent)}
         */
        public BasicDescriptiveStatisticsModel getModel() {
                return colmodel;
        }
        
        @Override
        public DoubleFV getFeatureVector() {
                return new DoubleFV(getFeatureVectorArray());
        }
}