Code viewer for World: MNIST character & doodle r...

// Cloned by Andrew Merrigan on 17 Dec 2019 from World "Character recognition neural network" by "Coding Train" project 
// Please leave this clone trail here.
 

// Port of Character recognition neural network from here:
// https://github.com/CodingTrain/Toy-Neural-Network-JS/tree/master/examples/mnist
// with many modifications 

// Name: Andrew Merrigan
// Student No: 19214610

// Based on:
// https://github.com/tensorflow/tfjs-vis/tree/master/tfjs-vis/demos/mnist
// https://storage.googleapis.com/tfjs-vis/mnist/dist/index.html
// https://www.tensorflow.org/js/guide

// --- defined by MNIST - do not change these ---------------------------------------
const PIXELS = 28;                       // images in data set are tiny 
const PIXELSSQUARED = PIXELS * PIXELS;

// number of training and test exemplars in the data set:Z

//--- can modify all these --------------------------------------------------

// no of nodes in network 

const LEARNING_RATE = 0.26;
const LEARNING_RATE_DECAY = 0.004;
const EPOCHS = 2;
const BATCH_SIZE = 300;

// Model constants
const CLASSES = 10;
const NUM_CLASSES = 10;


const TRAIN_DATA_SIZE = 60000;
const TEST_DATA_SIZE = 10000;

const IMAGE_SIZE = 28;

// should we train 
let stop_training = false;

// multiply it by this to magnify for display 
const ZOOMFACTOR = 7;
const ZOOMPIXELS = ZOOMFACTOR * PIXELS;

// 3 rows of
// large image + 50 gap + small image    
// 50 gap between rows 

const canvaswidth = (PIXELS + ZOOMPIXELS) + 50;
const canvasheight = (ZOOMPIXELS * 3) + 100;

const DOODLE_THICK = 25;    // thickness of doodle lines 
const DOODLE_BLUR = 8;      // blur factor applied to doodles 


// an object that provides functions to load batchs of data
let mnist;

let nn;

// images in LHS:
let doodle, demo;
let doodle_exists = false;
let demo_exists = false;

let mousedrag = false;      // are we in the middle of a mouse drag drawing?  


// save inputs to global var to inspect
// type these names in console 
var train_inputs, test_inputs, demo_inputs, doodle_inputs;

// CSS trick 
// make run header bigger 
$("#runheaderbox").css({ "max-height": "90vh", "max-width": "70vW" });

//--- start of AB.msgs structure: ---------------------------------------------------------
// We output a serious of AB.msgs to put data at various places in the run header 
var thehtml;

// 1 Doodle header 
thehtml = "<hr> <h1> 1. Doodle </h1> Top row: Doodle (left) and shrunk (right). <br> " +
  " Draw your doodle in top LHS. <button onclick='wipeDoodle();' class='normbutton' >Clear doodle</button> <br> ";
AB.msg(thehtml, 1);

// 2 Doodle variable data (guess)

// 3 Training header
thehtml = "<hr> <h1> 2. Training </h1> Middle row: Training image magnified (left) and original (right). <br>  " +
  " <button onclick='restartTraining();' class='normbutton' >Start training</button>  " +
  " <button onclick='stop_training = true;' class='normbutton' >Stop training</button> <br> " +
  " <button id='show-visor'  class='normbutton' >Show Metrics visor</button> <br> ";
AB.msg(thehtml, 3);

// 4 variable training data 
thehtml = "<div id='metrics'> </div>";
AB.msg(thehtml, 4);


// 6 variable testing data 

// 7 Demo header 
thehtml = "<hr> <h1> 3. Demo </h1> Bottom row: Test image magnified (left) and  original (right). <br>" +
  " The network is <i>not</i> trained on any of these images. <br> " +
  " <button onclick='makeDemo();' class='normbutton' >Demo test image</button> <br> ";
AB.msg(thehtml, 7);

// 8 Demo variable data (random demo ID)
// 9 Demo variable data (changing guess)

const greenspan = "<span style='font-weight:bold; font-size:x-large; color:darkgreen'> ";

//--- end of AB.msgs structure: ---------------------------------------------------------

let trainingPromise;

function setup() {
  createCanvas(canvaswidth, canvasheight);

  doodle = createGraphics(ZOOMPIXELS, ZOOMPIXELS);       // doodle on larger canvas 
  doodle.pixelDensity(1);

  // JS load other JS 
  // maybe have a loading screen while loading the JS and the data set 

  AB.loadingScreen();

  $.getScript("https://cdn.jsdelivr.net/npm/@tensorflow/tfjs-vis@1.0.2/dist/tfjs-vis.umd.min.js", () => {
    $.getScript("https://cdn.jsdelivr.net/npm/@tensorflow/tfjs@1.0.0/dist/tf.min.js", () => {
      $.getScript("/uploads/andrewmerrigan/tsModel.js", () => {
        $.getScript("/uploads/andrewmerrigan/mnist.js", () => {
          console.log("All JS loaded");
          nn = getModel();
          loadMNIST().then((data) => {
            mnist = data;
            console.log("All data loaded into mnist object:")
            console.log(mnist);
            AB.removeLoading();     // if no loading screen exists, this does nothing 
          }).then(() => {
            startTraining();
          });
        });
      });
    });
  });
}

function watchTraining() {
  document.querySelector('#show-visor').addEventListener('click', () => {
    const visorInstance = tfvis.visor();
    if (!visorInstance.isOpen()) {
      visorInstance.toggle();
    }
  });


  const metrics = ['acc', 'val_acc'];
  // const container = document.getElementById("metrics"); // puts the graph inline
  const container = {
    tab: 'Training',
    name: 'Training Metrics',
    styles: {
      height: '90vh'
    }
  };
  return tfvis.show.fitCallbacks(container, metrics, {
    height: 200
  });


}

// make a P5 image object from a raw data array   
function getImage(img) {
  let theimage = createImage(PIXELS, PIXELS);    // make blank image, then populate it 
  theimage.loadPixels();

  for (let i = 0; i < PIXELSSQUARED; i++) {
    let bright = img[i];
    let index = i * 4;
    theimage.pixels[index + 0] = bright;
    theimage.pixels[index + 1] = bright;
    theimage.pixels[index + 2] = bright;
    theimage.pixels[index + 3] = 255;
  }

  theimage.updatePixels();
  return theimage;
}

// convert img array into normalised input array 
function getInputs(img) {
  let inputs = [];
  for (let i = 0; i < PIXELSSQUARED; i++) {
    let bright = img[i];
    inputs[i] = bright / 255;       // normalise to 0 to 1
  }
  return (inputs);
}

function restartTraining() {
  if (!stop_training) {
    return;
  }
  stop_training = false;
  startTraining();
}

let trainImage;
// train the network with a single exemplar, from global var "train_index", show visual on or off 
function startTraining() {

  const [trainXs, trainYs] = mnist.getTrainTensor(TRAIN_DATA_SIZE);
  const [testXs, testYs] = mnist.getTestTensor(TEST_DATA_SIZE);
  // tf.enableDebugMode()
  fitCallbacks = watchTraining()

  // Override the callbacks provided by ts viz to allow training to be stopped and for images to cycle.
  let customCallbacks = {
    onEpochEnd: (epoch, logs) => {
      fitCallbacks.onEpochEnd(epoch, logs);
      status.value = `epoch ${epoch + 1}`;
      if (stop_training) {
        this.model.stopTraining = true;
      }
    },

    onBatchEnd: (batch, logs) => {
      fitCallbacks.onBatchEnd(batch, logs);
      if (batch % 8 == 0) {
        const trainImageTs = tf.slice(trainXs, batch * BATCH_SIZE + Math.floor(BATCH_SIZE / 2), 1).reshape([784]);
        trainImage = getImage(trainImageTs.arraySync());    // get image from data array 
        trainImageTs.dispose();
        AB.msg("<div>Accuracy: " + (Math.round(logs.acc * 100) / 100) + " </div>", 5);
      }
    }
  }

  return nn.fit(trainXs, trainYs, {
    batchSize: BATCH_SIZE,
    validationData: [testXs, testYs],
    epochs: EPOCHS,
    shuffle: true,
    callbacks: customCallbacks
  });
}


// --- the draw function -------------------------------------------------------------
// every step:
function draw() {
  // check if libraries and data loaded yet:
  if (typeof mnist == 'undefined') return;
  if (typeof nn == 'undefined') return;

  // how can we get white doodle on black background on yellow canvas?
  //        background('#ffffcc');    doodle.background('black');

  background('black');

  // keep drawing demo and doodle images 
  // and keep guessing - we will update our guess as time goes on 

  if (trainImage) {
    image(trainImage, 0, ZOOMPIXELS + 50, ZOOMPIXELS, ZOOMPIXELS);      // magnified 
    image(trainImage, ZOOMPIXELS + 50, ZOOMPIXELS + 50, PIXELS, PIXELS);
  }
  if (demo_exists) {
    drawDemo();
    guessDemo();
  }
  if (doodle_exists) {
    drawDoodle();
    guessDoodle();
  }

  // detect doodle drawing 
  // (restriction) the following assumes doodle starts at 0,0 
  // gets called when we click buttons, as well as if in doodle corner 
  if (mouseIsPressed) {
    // console.log ( mouseX + " " + mouseY + " " + pmouseX + " " + pmouseY );
    var MAX = ZOOMPIXELS + 20;     // can draw up to this pixels in corner 
    if ((mouseX < MAX) && (mouseY < MAX) && (pmouseX < MAX) && (pmouseY < MAX)) {
      mousedrag = true;       // start a mouse drag 
      doodle_exists = true;
      doodle.stroke('#FDFDFD');
      doodle.strokeWeight(DOODLE_THICK);
      doodle.line(mouseX, mouseY, pmouseX, pmouseY);
    }
  } else {
    // are we exiting a drawing
    if (mousedrag) {
      mousedrag = false;
    }
  }
}


//--- demo -------------------------------------------------------------
// demo some test image and predict it
// get it from test set so have not used it in training
function makeDemo() {
  demo_exists = true;
  var i = AB.randomIntAtoB(0, TEST_DATA_SIZE - 1);
  const [testXs, testYs] = mnist.getTestTensor(TEST_DATA_SIZE);
  demo = tf.slice(testXs, i, 1).reshape([784]).arraySync();
  var label = tf.slice(testYs, i, 1).argMax(-1).dataSync();

  thehtml = "Test image no: " + i + "<br>" +
    "Classification: " + label + "<br>";
  AB.msg(thehtml, 8);

  // type "demo" in console to see raw data 
}

function drawDemo() {
  var theimage = getImage(demo);
  image(theimage, 0, canvasheight - ZOOMPIXELS, ZOOMPIXELS, ZOOMPIXELS);      // magnified 
  image(theimage, ZOOMPIXELS + 50, canvasheight - ZOOMPIXELS, PIXELS, PIXELS);      // original
}

function guessDemo() {
  let inputs = getInputs(demo);

  let demo_inputs = tf.tensor2d(inputs, [1, PIXELSSQUARED]).reshape([1, 28, 28, 1]);
  let prediction = nn.predict(demo_inputs);  // array of outputs 
  predicted_values = prediction.dataSync()
  var values = predicted_values.slice();
  predicted_values.sort(function (a, b) { return b - a });

  thehtml = " We classify it as: " + greenspan + values.indexOf(predicted_values[0]) + "</span>" + " my second guess is: " + values.indexOf(predicted_values[1]);

  AB.msg(thehtml, 9);
  demo_inputs.dispose();
  prediction.dispose();
}

//--- doodle -------------------------------------------------------------
function drawDoodle() {
  // doodle is createGraphics not createImage
  let theimage = doodle.get();
  // console.log (theimage);

  image(theimage, 0, 0, ZOOMPIXELS, ZOOMPIXELS);      // original 
  image(theimage, ZOOMPIXELS + 50, 0, PIXELS, PIXELS);      // shrunk
}


function guessDoodle() {

  // doodle is createGraphics not createImage
  let img = doodle.get();

  img.resize(PIXELS, PIXELS);
  img.filter(BLUR, DOODLE_BLUR);
  img.loadPixels();

  // set up inputs   
  let inputs = [];
  for (let i = 0; i < PIXELSSQUARED; i++) {
    inputs[i] = img.pixels[i * 4] / 255;
  }

  doodle_inputs = tf.tensor2d(inputs, [1, PIXELSSQUARED]).reshape([1, 28, 28, 1]);

  // feed forward to make prediction 

  let prediction = nn.predict(doodle_inputs);
  predicted_values = prediction.dataSync()

  thehtml = " We classify it as: <br/>"
  var values = predicted_values.slice();
  predicted_values.sort(function (a, b) { return b - a });

  thehtml = thehtml + "Guess one:" + greenspan + values.indexOf(predicted_values[0]) + "</span><br/>"
    + "Guess two:" + values.indexOf(predicted_values[1]) + "<br/>"
    + "Guess three:" + values.indexOf(predicted_values[2]);


  AB.msg(thehtml, 2);
  prediction.dispose();
  doodle_inputs.dispose();
}

function wipeDoodle() {
  doodle_exists = false;
  doodle.background('black');
  thehtml = " We classify it as: <br/>Guess one: -</span><br/>"
    + "Guess two: - <br/>"
    + "Guess three: -";
  AB.msg(thehtml, 2);
}

// display inputs row by row, corresponding to square of pixels 
function showInputs(inputs) {
  var str = "";
  for (let i = 0; i < inputs.length; i++) {
    if (i % PIXELS == 0) str = str + "\n";                                   // new line for each row of pixels 
    var value = inputs[i];
    str = str + " " + value.toFixed(2);
  }
  console.log(str);
}