Creating and playing multiple ofSoundPlayers when detecting a circle

Hello!

I am using HoughCircles to detect circles from the video camera, and I want to play back a sound each time a circle is detected. With this code, a new player is created each time a circle is detected. I would create the beforehand in setup, but since I have no idea how many circles I will detect, I have to make them on the fly. The end goal is to have the app load and play a different sound depending on where the circle is detected on the screen. For now I am using the same sound.

I feel like though that I need to delete each player once its done, because the app stops playing sounds after awhile (it looks like it creates up to ~250 players, then no more sound).

Code is here: https://github.com/jdiedrick/circlesounds

And below:

.h

#pragma once

#include "ofxiOS.h"
#include "ofxCv.h"
#include "ofxGui.h"

class ofApp : public ofxiOSApp {

public:
    void setup();
    void update();
    void draw();
    void exit();

    void touchDown(ofTouchEventArgs & touch);
    void touchMoved(ofTouchEventArgs & touch);
    void touchUp(ofTouchEventArgs & touch);
    void touchDoubleTap(ofTouchEventArgs & touch);
    void touchCancelled(ofTouchEventArgs & touch);

    void lostFocus();
    void gotFocus();
    void gotMemoryWarning();
    void deviceOrientationChanged(int newOrientation);

ofImage img;

//for video grabber
ofVideoGrabber grabber;
ofImage gray;

cv::Mat cvMat;

vector<cv::Vec3f> circles;

ofxPanel gui;

ofxIntSlider dp_param;
ofxIntSlider mindist_param;
ofxIntSlider param1_param;
ofxIntSlider param2_param;
ofxIntSlider minradius_param;
ofxIntSlider maxradius_param;
ofxLabel numCircles;


//sound
ofSoundPlayer  vocals;
vector<ofSoundPlayer> players;

int numPlayers;
};

.mm

#include "ofApp.h"

//--------------------------------------------------------------
void ofApp::setup(){

//work with video grabber
grabber.initGrabber(ofGetWidth(), ofGetHeight());
gray.allocate(ofGetWidth(), ofGetHeight(), OF_IMAGE_GRAYSCALE);
ofxCv::allocate(cvMat, ofGetWidth(), ofGetHeight(), OF_IMAGE_GRAYSCALE);

//setup gui
gui.setup(); // most of the time you don't need a name
gui.add(dp_param.setup("dp param", 1, 0, 10));
gui.add(mindist_param.setup("min dist param", 200, 1, 1000));
gui.add(param1_param.setup("param1 param", 130, 0, 500));
gui.add(param2_param.setup("param2 param", 30, 0, 100));
gui.add(minradius_param.setup("min. radius param", 0, 0, 500));
gui.add(maxradius_param.setup("max. radius param", 400, 0, 500));
gui.add(numCircles.setup("# of circles size", ofToString((int)circles.size())));

numPlayers = 0; // keep track of how many players we're making

}

void ofApp::update(){

//ofSoundUpdate();


for (int i=0; i<players.size(); i++){
    cout << "playing player #: " << i << endl;
    players[i]->play();
}

players.clear();

grabber.update();
if (grabber.isFrameNew()){

    circles.clear();

    ofxCv::convertColor(grabber, gray, CV_RGB2GRAY);
    gray.update();
    
    cvMat = ofxCv::toCv(gray);
    cv::GaussianBlur( cvMat, cvMat, cv::Size(9, 9), 2, 2 );
    
    cv::HoughCircles( cvMat,
                     circles,
                     CV_HOUGH_GRADIENT,
                     dp_param,
                     mindist_param,
                     param1_param,
                     param2_param,
                     minradius_param,
                     maxradius_param );

    std::cout << "num circles " << circles.size() << endl;

    for (int i=0; i<circles.size(); i++){
        
        numPlayers++; // count number of players we're making
        cout << "num players: " << numPlayers << endl;
        
        ofSoundPlayer * player = new ofSoundPlayer();
        player->load("synth.mp3");
        //player->setVolume(ofMap(circles[i][2], 0, 100, 0.1, 1.0));
        //player->setSpeed( 0.1f + ((float)(ofGetHeight() - circles[i][1]) / (float)ofGetHeight()));
        players.push_back(player);
        
        /*
        if(player->isLoaded()){
            player->play();
        }
        */
        //players.clear();
        /*
        if(!player->isPlaying()){
            delete player;
        }
         */
    }
}

}

 //--------------------------------------------------------------
void ofApp::draw(){
gray.draw(0, 0);

ofPushStyle();
ofSetColor(255, 0, 0);
ofNoFill();
for (int i=0; i<circles.size(); i++) {
    ofDrawCircle(circles[i][0], circles[i][1], circles[i][2]);
}
ofPopStyle();

gui.draw();
}

I feel like the way to do this would actually just be to use multiplay (I've been working off of the ofSoundPlayer example), but that isn't supported on iOS...

I tried two methods as you can see in my code: deleting the pointer with the delete keyword after playing, or adding all the players to a vector clearing the vector after playing. Unfortunately I think I'm missing a bit of C++ essentials, but I feel like I'm almost there! Any help and strategies are much appreciated.