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.servotrack; 031 032import java.util.List; 033 034import org.openimaj.image.FImage; 035import org.openimaj.image.MBFImage; 036import org.openimaj.image.colour.RGBColour; 037import org.openimaj.image.connectedcomponent.ConnectedComponentLabeler; 038import org.openimaj.image.pixel.ConnectedComponent; 039import org.openimaj.image.pixel.ConnectedComponent.ConnectMode; 040import org.openimaj.math.geometry.point.Point2d; 041import org.openimaj.math.geometry.point.Point2dImpl; 042import org.openimaj.video.VideoDisplay; 043import org.openimaj.video.VideoDisplayListener; 044import org.openimaj.video.capture.VideoCapture; 045 046public class FrameDiffTrack { 047 public static void main(String[] args) throws Exception { 048 final VideoCapture capture = new VideoCapture(640, 480, VideoCapture.getVideoDevices().get(0)); 049 final PTServoController servos = new PTServoController("/dev/tty.usbmodemfa131"); 050 final Point2d frameCentre = new Point2dImpl(capture.getWidth() / 2, capture.getHeight() / 2); 051 052 VideoDisplay.createVideoDisplay(capture).addVideoListener(new VideoDisplayListener<MBFImage>() { 053 FImage previousFrame = capture.getCurrentFrame().flatten(); 054 int inhibit = 0; 055 056 @Override 057 public void beforeUpdate(MBFImage frame) { 058 final FImage thisFrame = frame.flatten(); 059 final FImage delta = thisFrame.subtract(previousFrame).abs().threshold(0.3f); 060 061 final ConnectedComponentLabeler ccl = new ConnectedComponentLabeler(ConnectMode.CONNECT_8); 062 final List<ConnectedComponent> comps = ccl.findComponents(delta); 063 064 if (inhibit <= 0 && comps.size() > 0) { 065 ConnectedComponent big = comps.get(0); 066 067 for (int i = 1; i < comps.size(); i++) { 068 final ConnectedComponent cc = comps.get(i); 069 if (cc.calculateArea() > big.calculateArea()) 070 big = cc; 071 } 072 073 if (big.calculateArea() > 500) { 074 frame.drawShape(big.toPolygon(), RGBColour.RED); 075 076 final Point2d pt = big.calculateCentroidPixel(); 077 078 final Point2d deltap = pt.minus(frameCentre); 079 080 final double damp = 0.03; 081 082 if (deltap.getX() < 0) { 083 servos.changePanBy(-(int) (damp * deltap.getX())); 084 } else if (deltap.getX() > 0) { 085 servos.changePanBy(-(int) (damp * deltap.getX())); 086 } 087 088 if (deltap.getY() < 0) { 089 servos.changeTiltBy((int) (damp * deltap.getY())); 090 } else if (deltap.getY() > 0) { 091 servos.changeTiltBy((int) (damp * deltap.getY())); 092 } 093 094 inhibit = 10; 095 } 096 } 097 098 previousFrame = thisFrame; 099 inhibit--; 100 } 101 102 @Override 103 public void afterUpdate(VideoDisplay<MBFImage> display) { 104 // do nothing 105 } 106 }); 107 108 } 109}