Facial recognition and training with node js

gistfile1.js

// Starkflow comments + github project node js 
// + https://github.com/jrgcubano/face-detection-node-opencv
// + http://blog.stevenedouard.com/stroll-node-facial-recognition-3rd-party-apis

/*I believe that you're using the node-opencv library ? You will need some more steps. You have to train your opencv system which than allows you to use the method "predictSync" from FaceRecongizer().

The node-opencv library has a FaceRecognizer Object which you first initialize.

Initialize FaceRecognizer: var FaceRecognizer = new cv.FaceRecognizer();
You have to read all the images, create a specific array and train your FaceRecognizer with that. For my purpose, I'm saving each user in a DB and they get a unique ID which I'm using to create a specific subfolder and this is later used. Here is my code:
*/

const path = require("path");
const fs = require("fs");
const cv = require("opencv");

const FaceRecognizer = new cv.FaceRecognizer();

let cvImages = [];

var uploadDir = path.join(".", "/uploads");
fs.readdir(uploadDir, function(err, files) {
  if (err) throw new Error(err);
  if (files.length > 0) {
    //There are some user related image folders
    files.forEach(function(subfolder, index, array) {
      if (subfolder != ".DS_Store") {
        //Issue with Mac, test on Linux-VM
        //We are now iterating over each subfolder
        var subFolderDir = path.join(uploadDir, "/" + subfolder);
        var images = fs.readdirSync(subFolderDir);
        //console.log(images);
        images.forEach(function(image, index, array) {
          //Get Matrix Objekt for each image to train OpenCV
          if (image != ".DS_Store") {
            var imageDir = path.join(subFolderDir, "/" + image);
            cv.readImage(imageDir, function(err, im) {
              var channels = im.channels();
              if (channels >= 3) {
                var labelNumber = parseInt(subfolder); //Create labelnumber; Account-Id starts by 1, labels for openCV start with 0
                cvImages.push(new Array(labelNumber, im)); //Add image to Array
              }
            });
          }
        });
      }
    });
    if (cvImages.length > 3) {
      console.log("Training images (we have at least 3 images)", cvImages);
      FaceRecognizer.trainSync(cvImages);
    } else {
      console.log("Not enough images uploaded yet", cvImages);
    }
  } else {
    console.log("There are no images uploaded yet!");
  }
});

setTimeout(() => {
  cv.readImage("./test/ishii.jpg", function(err, im) {
    if (err) res.send(err);
    var whoisit = FaceRecognizer.predictSync(im);
    console.log("Identified image", whoisit);
  });
}, 1000);