ofxcv multiple contour finders

main.cpp

#include "ofApp.h"

int main() {
	ofSetupOpenGL(640, 480, OF_WINDOW);
	ofRunApp(new ofApp());
}

ofApp.cpp

#include "ofApp.h"

using namespace ofxCv;
using namespace cv;

void ofApp::setup() {
	cam.setup(320, 240);
   
    for(int i=0; i<MAX_CAMS;i++){
        imitate(img[i], cam);
        contourFinder[i].setMinAreaRadius(10);
        contourFinder[i].setMaxAreaRadius(200);
    }
}

void ofApp::update() {
	cam.update();
    if(cam.isFrameNew()) {
        for(int i=0; i<MAX_CAMS;i++){
//            copy(img[i],cam);
            copy(cam,img[i]);
            img[i].update();
            contourFinder[i].setThreshold(ofMap(mouseX, 0, ofGetWidth(), 0, 255));
            contourFinder[i].findContours(img[i]);
        }
    }
}

void ofApp::draw() {
	ofSetColor(255);
    for(int i=0; i<MAX_CAMS;i++){
        int rows = i % 3;
        int cols = i / 3;
        ofPushMatrix();
        ofTranslate(cols*cam.getWidth(), rows*cam.getHeight());
        img[i].draw(0, 0);
        contourFinder[i].draw();
        ofPopMatrix();
    }
}

ofApp.h

#pragma once

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

#define MAX_CAMS 6
class ofApp : public ofBaseApp {
public:
	void setup();
	void update();
	void draw();
	
	ofVideoGrabber cam;
    ofImage img[MAX_CAMS];
	ofxCv::ContourFinder contourFinder[MAX_CAMS];
};