/**
 * 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.demos;

import java.io.File;
import java.io.IOException;
import java.util.List;

import org.openimaj.image.DisplayUtilities;
import org.openimaj.image.FImage;
import org.openimaj.image.ImageUtilities;
import org.openimaj.image.connectedcomponent.ConnectedComponentLabeler;
import org.openimaj.image.pixel.ConnectedComponent;
import org.openimaj.image.pixel.ConnectedComponent.ConnectMode;
import org.openimaj.image.processing.convolution.AverageBoxFilter;
import org.openimaj.image.processing.threshold.OtsuThreshold;
import org.openimaj.math.geometry.shape.Rectangle;

public class ImgDetector {

        public static void main(String[] args) throws IOException {
                final FImage img = ImageUtilities
                                .readF(new File(
                                                "/Users/jon/Library/Containers/com.apple.mail/Data/Library/Mail Downloads/BD5C21CA-CC93-4C38-A96D-A44E961C5544/in-2.jpg"));

                // blur the image, with more blur in the horizontal direction than
                // vertical
                final FImage i1 = img.process(new AverageBoxFilter(40, 10));

                // numerical issues from the way the box filter is implemented might
                // mean that there are values slightly bigger than 1, so clip the values
                // to a maximum of 1.
                i1.clip(0f, 1f);

                // threshold the image to make it purely black and white
                i1.processInplace(new OtsuThreshold());

                // invert the image before input to the ConnectedComponentLabeler
                i1.inverse();

                // Apply connected component labelling to find all the "blobs"
                final ConnectedComponentLabeler ccl = new ConnectedComponentLabeler(ConnectMode.CONNECT_8);
                final List<ConnectedComponent> ccs = ccl.findComponents(i1);

                // values for the computed bounds of the "graphic"
                int left = i1.width;
                int right = 0;
                int top = i1.height;
                int bottom = 0;

                // loop through the "blobs" and filter them
                for (final ConnectedComponent cc : ccs) {
                        final Rectangle bb = cc.calculateRegularBoundingBox();

                        // ignore components that are near the top edge
                        if (bb.y < 0.1 * i1.height)
                                continue;

                        // ignore components that are near the right edge
                        if (bb.x + bb.width > 0.9 * i1.width)
                                continue;

                        // filter the other components based on their width and the relative
                        // area of the blob to its bounding box (should be ~1 for a text
                        // block)
                        if (bb.width < 0.4 * i1.width || bb.calculateArea() / cc.calculateArea() > 2) {
                                if (bb.x < left)
                                        left = (int) bb.x;
                                if (bb.x + bb.width > right)
                                        right = (int) (bb.x + bb.width);
                                if (bb.y < top)
                                        top = (int) bb.y;
                                if (bb.y + bb.height > bottom)
                                        bottom = (int) (bb.y + bb.height);
                                i1.drawShape(bb, 0.5f);
                        }
                }

                // construct the final bounds rectangle (might want to extend/pad it)
                final Rectangle bounds = new Rectangle(left, top, right - left, bottom - top);
                DisplayUtilities.display(img.extractROI(bounds));
        }
}