/**
 * 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.processing.face.detection;

import java.io.DataInput;
import java.io.DataOutput;
import java.io.IOException;

import org.openimaj.image.FImage;
import org.openimaj.image.ImageUtilities;
import org.openimaj.io.ReadWriteableBinary;
import org.openimaj.math.geometry.shape.Rectangle;
import org.openimaj.math.geometry.shape.Shape;

/**
 * A DetectedFace models a face detected by a face detector, together with the
 * locations of certain facial features localised on the face.
 *
 * @author Jonathon Hare
 *
 */
public class DetectedFace implements ReadWriteableBinary {
        /**
         * The upright bounds of the face in the image in which it was detected
         */
        protected Rectangle bounds;

        /**
         * The extracted sub-image representing the face. This is normally extracted
         * directly from the bounds rectangle in the original image, but in some
         * cases might be extracted from a sub-region of the bounds rectangle.
         */
        protected FImage facePatch;

        /**
         * The confidence of the detection; higher numbers mean higher confidence.
         */
        protected float confidence = 1;

        /**
         * Default constructor with an empty rectangle as bounds
         */
        public DetectedFace() {
                this.bounds = new Rectangle();
        }

        /**
         * Construct with a bounds rectangle (the bounding box of the face in the
         * detection image) and an image patch that describes the contents of the
         * bounds rectangle from the original image.
         *
         * @param bounds
         *            The bounding box of the face in the detection image.
         * @param patch
         *            The subimage describing the contents of the bounding box.
         * @param confidence
         *            The confidence of the detection.
         */
        public DetectedFace(final Rectangle bounds, final FImage patch, final float confidence) {
                this.bounds = bounds;
                this.facePatch = patch;
                this.confidence = confidence;
        }

        /**
         *      Returns the sub-image representing the face.
         *      @return Get the sub-image representing the detected face
         */
        public FImage getFacePatch() {
                return this.facePatch;
        }

        /**
         *      Reset the face patch image
         *      @param img The image
         */
        public void setFacePatch( final FImage img )
        {
                this.facePatch = img;
        }

        /**
         * Get the bounding box of the face in the detection image. This might be
         * the same as the shape returned by {@link #getShape()}, or it might
         * encompass that shape.
         *
         * @return The bounding box of the face in the detection image
         */
        public Rectangle getBounds() {
                return this.bounds;
        }

        /**
         *      Set the bounds of this face. This is so that detected face objects
         *      can be updated if the bounds were inaccurate, or tracking is taking
         *      place on the object.
         *      @param rect The new bounds
         */
        public void setBounds( final Rectangle rect )
        {
                this.bounds = rect;
        }

        @Override
        public void writeBinary(final DataOutput out) throws IOException {
                this.bounds.writeBinary(out);
                ImageUtilities.write(this.facePatch, "png", out);
        }

        @Override
        public byte[] binaryHeader() {
                return "DF".getBytes();
        }

        @Override
        public void readBinary(final DataInput in) throws IOException {
                this.bounds.readBinary(in);
                this.facePatch = ImageUtilities.readF(in);
        }

        /**
         * Get the confidence of the detection. Higher numbers mean higher
         * confidence.
         *
         * @return the confidence.
         */
        public float getConfidence() {
                return this.confidence;
        }

        /**
         * Get the shape of the detection. In most cases, this will just return the
         * bounds rectangle, however, subclasses can override to return a better
         * geometric description of the detection area.
         *
         * @return the shape describing the detection in the original image.
         */
        public Shape getShape() {
                return this.bounds;
        }

        /**
         * Set the confidence of the detection. Higher numbers mean higher
         * confidence.
         *
         * @param confidence
         *            the confidence.
         */
        public void setConfidence(final int confidence) {
                this.confidence = confidence;
        }
}