ofxCv example - contours follower

ofApp.cpp

#include "ofApp.h"

using namespace ofxCv;
using namespace cv;

void Glow::setup(const cv::Rect& track) {
    color.setHsb(ofRandom(0, 255), 255, 255);
    cur = toOf(track).getCenter();
    smooth = cur;
}

void Glow::update(const cv::Rect& track) {
    cout << "update: " << dyingTime << endl;
    cur = toOf(track).getCenter();
    smooth.interpolate(cur, .5);
    all.addVertex(smooth);
}

void Glow::kill() {
    cout << "kill: " << dyingTime << endl;
    float curTime = ofGetElapsedTimef();
    if(startedDying == 0) {
        startedDying = curTime;
    } else if(curTime - startedDying > dyingTime) {
        dead = true;
    }
}

void Glow::draw() {
    cout << "draw: " << dyingTime << endl;
    ofPushStyle();
    float size = 16;
    ofSetColor(255);
    if(startedDying) {
        ofSetColor(ofColor::red);
        size = ofMap(ofGetElapsedTimef() - startedDying, 0, dyingTime, size, 0, true);
    }
    ofNoFill();
    ofDrawCircle(cur, size);
    ofSetColor(color);
    all.draw();
    ofSetColor(255);
    ofDrawBitmapString(ofToString(label), cur);
    ofPopStyle();
}

void ofApp::setup() {
    ofSetVerticalSync(true);
    ofBackground(0);
    
    movie.load("test.mov");
    movie.play();
    
    contourFinder.setMinAreaRadius(1);
    contourFinder.setMaxAreaRadius(100);
    contourFinder.setThreshold(80);
    
    tracker.setPersistence(15);
    tracker.setMaximumDistance(50);
    
}

void ofApp::update() {
    movie.update();
    if(movie.isFrameNew()) {
        blur(movie, 10);
        contourFinder.findContours(movie);
        tracker.track(contourFinder.getBoundingRects());
    }
    vector<Glow> & followers = tracker.getFollowers();
    for(int i = 0; i < followers.size(); i++) {
        followers[i].dyingTime = 10;
    }
}

void ofApp::draw() {
    ofSetColor(255);
    movie.draw(0, 0);
    contourFinder.draw();
    vector<Glow> & followers = tracker.getFollowers();
    for(int i = 0; i < followers.size(); i++) {
        followers[i].draw();
        int temp_label = followers[i].getLabel();
    }
}

ofApp.h

#pragma once

#include "ofMain.h"
#include "ofxCv.h"

class Glow : public ofxCv::RectFollower {
protected:
    ofColor color;
    ofVec2f cur, smooth;
    float startedDying;
    ofPolyline all;
public:
    float dyingTime;
    
    Glow()
    :startedDying(0) {
        dyingTime = 0.5;
    }
    void setup(const cv::Rect& track);
    void update(const cv::Rect& track);
    void kill();
    void draw();
};

class ofApp : public ofBaseApp {
public:
    void setup();
    void update();
    void draw();
    
    ofVideoPlayer movie;
    ofxCv::ContourFinder contourFinder;
    ofxCv::RectTrackerFollower<Glow> tracker;
};