Simple object tracker

objecttracker.js

 function huntForPets(monitoredItem, detectionArray, target) {
   // naughtyAnimals is an array that keeps track of each animal are in frame
   var naughtyAnimals = [];
   
   // Loop through all of the objects recognized by the API
   for (let i = 0; i < detectionArray.length; i++) {
     // If we found one of the objects we were looking for...
     if (detectionArray[i].class === target && detectionArray[i].score > MIN_DETECTION_CONFIDENCE) {
       // Draw a bounding box on screen
       renderFoundObject(detectionArray[i]);
       
       // Check if there's an intersection between the object of interest (i.e. dog) and the intersection object (i.e. couch)
       if (checkIfNear(monitoredItem, detectionArray[i])) {
         // If so, add it to the naughtyAnimals array!
         naughtyAnimals.push(detectionArray[i]);
       }
     }
   }
   
   // If there are more animals in frame this time than there were last time, send an alert
   if (naughtyAnimals.length > lastNaughtyAnimalCount) {
     lastNaughtyAnimalCount = naughtyAnimals.length;
 
     if (sendAlerts) {
       sendAlerts = false;
       sendAlert(naughtyAnimals);
       // Cool down to avoid too many notifications too fast in any scenario
       setTimeout(cooldown, MIN_ALERT_COOLDOWN_TIME * 1000);
     }
   } else if (naughtyAnimals.length === 0) {
     // If all animals left, reset animal counter so we start triggering events 
     // again when one comes back in frame.
     lastNaughtyAnimalCount = 0;
   }
 }