Code viewer for World: Character recognition neur...

// Cloned by Sumit Khopkar on 3 Dec 2021 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 


// --- 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:
const NOTRAIN = 60000;
const NOTEST  = 10000;



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

// no of nodes in network 
const noinput  = PIXELSSQUARED;
const nohidden = 64;
const nooutput = 3;

const learningrate = 0.1;   // default 0.1  
//CA686//
let do_training;
let nn_exists = false; //Variable to check if object of neural network exists

//Load the neural network object from the server if it exists
AB.queryDataExists ( function ( exists ) { 
    
    if(exists){
        do_training = false; //if neural network object retrieved then do not train
        AB.restoreData ( function ( nn ) { 
            nn_exists = true;
        } );
    }
    else{
        do_training = true; //if neural network object is not retrieved then train
    }
} );
//CA686//

// how many to train and test per timestep 
const TRAINPERSTEP = 10;
const TESTPERSTEP  = 1;

// multiply it by this to magnify for display 
const ZOOMFACTOR    = 70;                        
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 = 18;    // thickness of doodle lines 
const DOODLE_BLUR = 1;      // blur factor applied to doodles 

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;

// make run header bigger
AB.headerCSS ( { "max-height": "95vh" } );

//--- 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> Doodle </h1>" +
        " Draw your doodle in LHS. It can be either a cat, a rainbow, or a train. <button onclick='wipeDoodle();' class='normbutton' >Clear doodle</button> <br> ";
   AB.msg ( thehtml, 1 );
  
const greenspan = "<span style='font-weight:bold; font-size:x-large; color:darkgreen'> "  ;

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

//CA686//

//function to calculate sigmoid value
function sigmoid(x) {
  return 1 / (1 + Math.exp(-x));
}

//function to calculate tanh value
function dsigmoid(y) {
  // return sigmoid(x) * (1 - sigmoid(x));
  return y * (1 - y);
}

//Implemented softmax
function softmax(arr) {
  let sum = 0;
  let softmax_arr = [[0], [0], [0]];
  console.log("arr", arr);
  
  for(let i = 0; i < arr.length; i++){
    sum = sum + Math.exp(arr[i]);
  }
  
  for(let i = 0; i < arr.length; i++){
    softmax_arr[i][0] = Math.exp(arr[i]) / sum;
  }
  console.log("arr", arr);

  return softmax_arr;
}

//class Matrix contains methods to perform Matrix Operations
class Matrix {
  constructor(rows, cols) {
    this.rows = rows;
    this.cols = cols;
    this.data = [];

    for (let i = 0; i < this.rows; i++) {
      this.data[i] = [];
      for (let j = 0; j < this.cols; j++) {
        this.data[i][j] = 0;
      }
    }
  }

  static fromArray(arr) {
    let m = new Matrix(arr.length, 1);
    for (let i = 0; i < arr.length; i++) {
      m.data[i][0] = arr[i];
    }
    return m;
  }

  static subtract(a, b) {
    // Return a new Matrix a-b
    let result = new Matrix(a.rows, a.cols);
    for (let i = 0; i < result.rows; i++) {
      for (let j = 0; j < result.cols; j++) {
        result.data[i][j] = a.data[i][j] - b.data[i][j];
      }
    }
    return result;
  }

  //Implemented categorical cross-entropy
  //Failed due to infinity error
  static cross_entropy(target_out, model_out){
    let cross_ent_err = new Matrix(target_out.rows, target_out.cols);

    for(let i = 0; i < cross_ent_err.rows; i++){
      for (let j = 0; j < cross_ent_err.cols; j++){
        cross_ent_err.data[i][j] = cross_ent_err.data[i][j] + (target_out.data[i][j]*Math.log(model_out.data[i][j]));
      }
    }

    for(let i = 0; i < cross_ent_err.rows; i++){
      for (let j = 0; j < cross_ent_err.cols; j++){
        cross_ent_err.data[i][j] = -cross_ent_err.data[i][j];
      }
    }

    return cross_ent_err;
  }

  toArray() {
    let arr = [];
    for (let i = 0; i < this.rows; i++) {
      for (let j = 0; j < this.cols; j++) {
        arr.push(this.data[i][j]);
      }
    }
    return arr;
  }

  randomize() {
    for (let i = 0; i < this.rows; i++) {
      for (let j = 0; j < this.cols; j++) {
        this.data[i][j] = Math.random() * 2 - 1;
      }
    }
  }

  add(n) {
    if (n instanceof Matrix) {
      for (let i = 0; i < this.rows; i++) {
        for (let j = 0; j < this.cols; j++) {
          this.data[i][j] += n.data[i][j];
        }
      }
    } else {
      for (let i = 0; i < this.rows; i++) {
        for (let j = 0; j < this.cols; j++) {
          this.data[i][j] += n;
        }
      }
    }
  }

  static transpose(matrix) {
    let result = new Matrix(matrix.cols, matrix.rows);
    for (let i = 0; i < matrix.rows; i++) {
      for (let j = 0; j < matrix.cols; j++) {
        result.data[j][i] = matrix.data[i][j];
      }
    }
    return result;
  }

  static multiply(a, b) {
    // Matrix product
    if (a.cols !== b.rows) {
      console.log('Columns of A must match rows of B.')
      return undefined;
    }
    let result = new Matrix(a.rows, b.cols);
    for (let i = 0; i < result.rows; i++) {
      for (let j = 0; j < result.cols; j++) {
        // Dot product of values in col
        let sum = 0;
        for (let k = 0; k < a.cols; k++) {
          sum += a.data[i][k] * b.data[k][j];
        }
        result.data[i][j] = sum;
      }
    }
    return result;
  }

  multiply(n) {
    console.log("non-static multiply");
    if (n instanceof Matrix) {
      // hadamard product
      for (let i = 0; i < this.rows; i++) {
        for (let j = 0; j < this.cols; j++) {
          this.data[i][j] *= n.data[i][j];
        }
      }
    } else {
      // Scalar product
      for (let i = 0; i < this.rows; i++) {
        for (let j = 0; j < this.cols; j++) {
          this.data[i][j] *= n;
        }
      }
    }
  }

  map(func) {
    // Apply a function to every element of matrix
    for (let i = 0; i < this.rows; i++) {
      for (let j = 0; j < this.cols; j++) {
        let val = this.data[i][j];
        this.data[i][j] = func(val);
      }
    }
  }

  static map(matrix, func) {
    let result = new Matrix(matrix.rows, matrix.cols);
    // Apply a function to every element of matrix
    for (let i = 0; i < matrix.rows; i++) {
      for (let j = 0; j < matrix.cols; j++) {
        let val = matrix.data[i][j];
        result.data[i][j] = func(val);
      }
    }
    return result;
  }

  print() {
    console.table(this.data);
  }
}


if (typeof module !== 'undefined') {
  module.exports = Matrix;
}

class NeuralNetwork {
  //Added code for learning rate
  constructor(input_nodes, hidden_nodes, output_nodes, learning_rate) {
    console.log("Constructor");
    console.error("error");
    this.input_nodes = input_nodes;
    this.hidden_nodes = hidden_nodes;
    this.output_nodes = output_nodes;

    this.weights_ih = new Matrix(this.hidden_nodes, this.input_nodes);
    this.weights_ho = new Matrix(this.output_nodes, this.hidden_nodes);
    this.weights_ih.randomize();
    this.weights_ho.randomize();

    this.bias_h = new Matrix(this.hidden_nodes, 1);
    this.bias_o = new Matrix(this.output_nodes, 1);
    this.bias_h.randomize();
    this.bias_o.randomize();
    this.learning_rate = learning_rate; //Change to CodingTrain code 
  }

  feedforward(input_array) {

    // Generating the Hidden Outputs
    let inputs = Matrix.fromArray(input_array);
    let hidden = Matrix.multiply(this.weights_ih, inputs);
    hidden.add(this.bias_h);
    // activation function!
    hidden.map(sigmoid);

    // Generating the output's output!
    let output = Matrix.multiply(this.weights_ho, hidden);
    output.add(this.bias_o);
    output.map(sigmoid);

    // Sending back to the caller!
    return output.toArray();
  }

  train(input_array, target_array) {
    // Generating the Hidden Outputs
    let inputs = Matrix.fromArray(input_array);
    console.log("inputs", inputs);
    let hidden = Matrix.multiply(this.weights_ih, inputs);
    hidden.add(this.bias_h);
    // activation function!
    hidden.map(sigmoid);

    // Generating the output's output!
    console.log("this.weights_ho", this.weights_ho);
    let outputs = Matrix.multiply(this.weights_ho, hidden);
    outputs.add(this.bias_o);
    //CA686//
    //outputs.map(sigmoid);
    outputs.data = softmax(outputs.data); //The outputs now pass through softmax function instead of sigmoid function
    //CA686//
    console.log("outputs.data", outputs.data);

    // Convert array to matrix object
    let targets = Matrix.fromArray(target_array);

    // Calculate the error
    // ERROR = TARGETS - OUTPUTS
    //CA686//
    let output_errors = Matrix.subtract(targets, outputs);
    //let output_errors = Matrix.cross_entropy(targets, outputs); //Failed attempt to implement cross-entropy
    //CA686//
    console.log("output_errors", output_errors);
    console.log("outputs", outputs);
    // let gradient = outputs * (1 - outputs);
    // Calculate gradient
    let gradients = Matrix.map(outputs, dsigmoid);
    gradients.multiply(output_errors);
    console.log("gradients", gradients);
    gradients.multiply(this.learning_rate);


    // Calculate deltas
    let hidden_T = Matrix.transpose(hidden);
    let weight_ho_deltas = Matrix.multiply(gradients, hidden_T);

    // Adjust the weights by deltas
    this.weights_ho.add(weight_ho_deltas);
    // Adjust the bias by its deltas (which is just the gradients)
    this.bias_o.add(gradients);

    // Calculate the hidden layer errors
    let who_t = Matrix.transpose(this.weights_ho);
    let hidden_errors = Matrix.multiply(who_t, output_errors);

    // Calculate hidden gradient
    let hidden_gradient = Matrix.map(hidden, dsigmoid);
    hidden_gradient.multiply(hidden_errors);
    hidden_gradient.multiply(this.learning_rate);

    // Calcuate input->hidden deltas
    let inputs_T = Matrix.transpose(inputs);
    let weight_ih_deltas = Matrix.multiply(hidden_gradient, inputs_T);

    this.weights_ih.add(weight_ih_deltas);
    // Adjust the bias by its deltas (which is just the gradients)
    this.bias_h.add(hidden_gradient);
    // outputs.print();
    // targets.print();
    // error.print();
  }

  predict(input_array) {

    // Generating the Hidden Outputs
    console.log("input_array", input_array);
    let inputs = Matrix.fromArray(input_array);
    let hidden = Matrix.multiply(this.weights_ih, inputs);
    hidden.add(this.bias_h);
    // activation function!
    //hidden.map(this.activation_function.func);
    hidden.map(sigmoid);

    // Generating the output's output!
    let output = Matrix.multiply(this.weights_ho, hidden);
    output.add(this.bias_o);
    //output.map(this.activation_function.func);
    //CA686//
    //output.map(sigmoid);
    output.data = softmax(output.data); ////The outputs now pass through softmax function instead of sigmoid function
    //CA686//

    // Sending back to the caller!
    console.log("output", output);
    return output.toArray();
  }

}

const len = 784; //Total number of pixels
const totalData = 500; //Total images to be considered

//Assign integers for deciding the class of the objects
const CAT = 0;
const RAINBOW = 1;
const TRAIN = 2;

let catsData;
let trainsData;
let rainbowsData;

let cats = {};
let trains = {};
let rainbows = {};

var doodle_list = [];
var doodle_list_data = [];
var doodle_num_list = [];

var epochCounter = 0;

//failed to generalize
function preload() {
    catsData = loadBytes('uploads/sumitkhopkar25/cats1000.bin');
    trainsData = loadBytes('uploads/sumitkhopkar25/trains1000.bin');
    rainbowsData = loadBytes('uploads/sumitkhopkar25/rainbows1000.bin');
}

//CA686//

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();

//CA686//
console.log ("All JS loaded");
if(nn_exists == false){
    nn = new NeuralNetwork(  noinput, nohidden, nooutput, learningrate);
}

//nn.setLearningRate ( learningrate );
loadData();
console.log("cats.training", cats.training);
//CA686//
}



// load data set from local file (on this server)

function loadData()    
{
  //CA680//

  // Preparing the data

  doodle_list = [cats, rainbows, trains];
  doodle_list_data = [catsData, rainbowsData, trainsData];
  doodle_num_list = [CAT, RAINBOW, TRAIN];

  for(let j = 0; j < doodle_list.length; j++){
    console.log("j", j);
    doodle_list[j].training = [];
    doodle_list[j].testing = [];
    //Create training and testing data
    for (let i = 0; i < totalData; i++) {
      let offset = i * len; 
      let threshold = floor(0.8 * totalData);
      if (i < threshold) {
        doodle_list[j].training[i] = doodle_list_data[j].bytes.subarray(offset, offset + len);
        doodle_list[j].training[i].label = doodle_num_list[j];
      } else {
        doodle_list[j].testing[i - threshold] = doodle_list_data[j].bytes.subarray(offset, offset + len);
        doodle_list[j].testing[i - threshold].label = doodle_num_list[j];
      }
    }
  }

  console.log("cats.training", cats.training);
  
  AB.removeLoading();     // if no loading screen exists, this does nothing 
  //CA680//
}

//CA686//
function trainEpoch(training) {
  shuffle(training, true);

  // Train for one epoch
  for (let i = 0; i < training.length; i++) {
    let data = training[i];
    let inputs = Array.from(data).map(x => x / 255);
    let label = training[i].label;
    let targets = [0, 0, 0];
    targets[label] = 1;
    console.log("inputs", inputs);
    console.log("targets", targets);
    console.log("nn.weights_ih", nn.weights_ih); 
    nn.train(inputs, targets);
  }
}

function testAll(testing) {

  let correct = 0;
  // Test for one epoch
  for (let i = 0; i < testing.length; i++) {
    // for (let i = 0; i < 1; i++) {
    let data = testing[i];
    let inputs = Array.from(data).map(x => x / 255);
    let label = testing[i].label;
    let guess = nn.predict(inputs);

    let m = max(guess);
    let classification = guess.indexOf(m);

    if (classification === label) {
      correct++;
    }
  }
  let percent = 100 * correct / testing.length;
  return percent;

}
//CA686//
 

function trainit (show)        // train the network with a single exemplar, from global var "train_index", show visual on or off 
{
  //CA686//
  
  // Randomizing the data
  let training = [];
  console.log("cats in training", cats);
  //Prepare entire training dataset
  training = training.concat(cats.training);
  training = training.concat(rainbows.training);
  training = training.concat(trains.training);
  console.log("training", training);
  trainEpoch(training);
  epochCounter++;
  console.log("Epoch: " + epochCounter);
}


function testit()    // test the network with a single exemplar, from global var "test_index"
{ 
  //CA686//
  let testing = [];
  //Prepare testing data
  testing = testing.concat(cats.testing);
  testing = testing.concat(rainbows.testing);
  testing = testing.concat(trains.testing);

  let percent = testAll(testing);
  console.log("Percent: " + nf(percent, 2, 2) + "%");

  let inputs = [];
  let img = get();
  img.resize(28, 28);
  img.loadPixels();
  for (let i = 0; i < len; i++) {
    let bright = img.pixels[i * 4];
    inputs[i] = (255 - bright) / 255.0;
  }

  let guess = nn.predict(inputs);

  //Classify as per the highest probability from the probability distribution
  let m = max(guess);
  let classification = guess.indexOf(m);

  if (classification === CAT) {
    console.log("cat");
  } else if (classification === RAINBOW) {
    console.log("rainbow");
  } else if (classification === TRAIN) {
    console.log("train");
  }

  //CA686//

}

// --- the draw function -------------------------------------------------------------
// every step:
 
function draw() 
{
  // check if libraries and data loaded yet:
  //CA686//
  if ( typeof doodle_list == 'undefined' || doodle_list.length == 0 ) return; //Doodle list is defined after loadData and draw is called at every step
  //CA686//

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

background ('black');

if ( do_training )    
{
  // do some training per step 
    for (let i = 0; i < TRAINPERSTEP; i++) 
    {
      if (i == 0)    trainit(true);    // show only one per step - still flashes by  
      else           trainit(false);
    }

    do_training = false;
    AB.saveData ( nn ); //Save the model onto the server
    
  // do some testing per step 
    for (let i = 0; i < TESTPERSTEP; i++) 
      testit();
}
//throw new Error("Something went badly wrong!");
// keep drawing demo and doodle images 
// and keep guessing - we will update our guess as time goes on 

/*if ( demo_exists )
{
  drawDemo();
  guessDemo();
}*/
if ( doodle_exists ) 
{
  drawDoodle();
  guessDoodle(); //Guess the doodle tgat is draw on the screen
}


// detect doodle drawing 
// (restriction) the following assumes doodle starts at 0,0 

  if ( mouseIsPressed )         // gets called when we click buttons, as well as if in doodle corner  
  {
     // 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('white');
        doodle.strokeWeight( DOODLE_THICK );
        doodle.line(mouseX, mouseY, pmouseX, pmouseY);      
     }
  }
  else 
  {
      // are we exiting a drawing
      if ( mousedrag )
      {
            mousedrag = false;
            // console.log ("Exiting draw. Now blurring.");
            //Removed because it was slowing the prediction
            //doodle.filter (BLUR, DOODLE_BLUR);    // just blur once 
            //   console.log (doodle);
      }
  }
}

//--- doodle -------------------------------------------------------------

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

  // set up inputs   
  let inputs = [];
  for (let i = 0; i < PIXELSSQUARED ; i++) 
  {
     inputs[i] = img.pixels[i * 4] / 255;
  }
  
  doodle_inputs = inputs;     // can inspect in console 
  // feed forward to make prediction 
  let prediction    = nn.predict(inputs);       // array of outputs 
  //CA686//
  console.log("prediction", prediction);
  let m = max(prediction);
  let classification = prediction.indexOf(m);

  if (classification === CAT) {
    classification = "cat";
  } else if (classification === RAINBOW) {
    classification = "rainbow";
  } else if (classification === TRAIN) {
    classification = "train";
  }

  thehtml =   " We classify it as: " + greenspan + classification + "</span> <br>" +
  //CA686//
  
  AB.msg ( thehtml, 2 );
}

function wipeDoodle()    
{
    doodle_exists = false;
    doodle.background('black');
}