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.demos.sandbox.hand;
031
032import java.util.ArrayList;
033import java.util.List;
034
035import javax.swing.JFrame;
036
037import org.openimaj.image.DisplayUtilities;
038import org.openimaj.image.FImage;
039import org.openimaj.image.MBFImage;
040import org.openimaj.image.colour.RGBColour;
041import org.openimaj.image.connectedcomponent.ConnectedComponentLabeler;
042import org.openimaj.image.pixel.ConnectedComponent;
043import org.openimaj.image.pixel.ConnectedComponent.ConnectMode;
044import org.openimaj.image.processing.threshold.OtsuThreshold;
045import org.openimaj.math.geometry.point.Point2d;
046import org.openimaj.math.geometry.shape.Circle;
047import org.openimaj.math.geometry.shape.Polygon;
048import org.openimaj.math.geometry.shape.algorithm.ConvexityDefect;
049import org.openimaj.video.capture.VideoCapture;
050import org.openimaj.video.capture.VideoCaptureException;
051
052public class Fingers {
053        public static void main(String[] args) throws VideoCaptureException {
054                final VideoCapture vc = new VideoCapture(320, 240);
055
056                final JFrame frame = DisplayUtilities.displaySimple(vc.getNextFrame(), "capture");
057                final ConnectedComponentLabeler ccl = new ConnectedComponentLabeler(ConnectMode.CONNECT_4);
058
059                while (true) {
060                        final MBFImage cimg = vc.getNextFrame();
061                        final FImage gimg = cimg.flatten();
062                        gimg.processInplace(new OtsuThreshold());
063                        // gimg.threshold(0.4f);
064
065                        ccl.analyseImage(gimg);
066                        final ConnectedComponent hand = findBiggest(ccl.getComponents());
067
068                        cimg.drawPoints(hand, RGBColour.WHITE, 1);
069
070                        if (hand != null) {
071                                Polygon poly = hand.toPolygon();
072                                poly = poly.reduceVertices(3);
073
074                                final Polygon chull = poly.calculateConvexHull();
075
076                                final List<ConvexityDefect> defects = ConvexityDefect.findDefects(poly, chull);
077                                // for (final ConvexityDefect cd : defects) {
078                                // cimg.drawShapeFilled(cd.getTriangle(), RGBColour.MAGENTA);
079                                // }
080
081                                final List<Point2d> tips = findTips(defects);
082
083                                final Point2d centroid = poly.calculateCentroid();
084                                System.out.println(centroid);
085
086                                for (final Point2d pt : tips) {
087                                        cimg.drawLine(centroid, pt, RGBColour.RED);
088                                        cimg.drawShape(new Circle(pt, 5), RGBColour.CYAN);
089                                }
090
091                                cimg.drawPolygon(poly, 1, RGBColour.RED);
092                                cimg.drawPolygon(chull, 1, RGBColour.BLUE);
093                        }
094
095                        DisplayUtilities.display(cimg, frame);
096                }
097        }
098
099        private static final int MIN_FINGER_DEPTH = 20;
100        private static final int MAX_FINGER_ANGLE = 60; // degrees
101
102        private static List<Point2d> findTips(List<ConvexityDefect> defects) {
103                final ArrayList<Point2d> fingerTips = new ArrayList<Point2d>();
104
105                for (int i = 0; i < defects.size(); i++) {
106                        if (defects.get(i).depth < MIN_FINGER_DEPTH) // defect too shallow
107                                continue;
108
109                        // look at fold points on either side of a tip
110                        final int prevIdx = (i == 0) ? (defects.size() - 1) : (i - 1);
111                        final int nextIdx = (i == defects.size() - 1) ? 0 : (i + 1);
112
113                        final int angle = angleBetween(defects.get(i).start, defects.get(prevIdx).deepestPoint,
114                                        defects.get(nextIdx).deepestPoint);
115                        if (angle >= MAX_FINGER_ANGLE)
116                                continue; // angle between finger and folds too wide
117
118                        // this point is probably a fingertip, so add to list
119                        fingerTips.add(defects.get(i).start);
120                }
121
122                return fingerTips;
123        }
124
125        // calculate the angle between the tip and its neighboring folds
126        // (in integer degrees)
127        private static int angleBetween(Point2d tip, Point2d next, Point2d prev)
128        {
129                return Math.abs((int) Math.round(
130                                Math.toDegrees(
131                                                Math.atan2(next.getX() - tip.getX(), next.getY() - tip.getY()) -
132                                                                Math.atan2(prev.getX() - tip.getX(), prev.getY() - tip.getY()))));
133        }
134
135        static ConnectedComponent findBiggest(List<ConnectedComponent> components) {
136                ConnectedComponent biggest = null;
137                int size = 0;
138
139                for (final ConnectedComponent cc : components) {
140                        if (cc.pixels.size() > size) {
141                                size = cc.pixels.size();
142                                biggest = cc;
143                        }
144                }
145
146                return biggest;
147        }
148}