Code viewer for World: Character recognition neur...

// Cloned by Ger Gleeson on 8 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 


// --- 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 = 85;
const nooutput = 10;

const learningrate = 0.1;   // default 0.1  

// should we train every timestep or not 
let do_training = true;

// how many to train and test per timestep 
const TRAINPERSTEP = 30;
const TESTPERSTEP  = 5;

// 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 = 18;    // thickness of doodle lines 
const DOODLE_BLUR = 3;      // blur factor applied to doodles 


let mnist;      
// all data is loaded into this 
// mnist.train_images
// mnist.train_labels
// mnist.test_images
// mnist.test_labels


let nn;

let trainrun = 1;
let train_index = 0;

let testrun = 1;
let test_index = 0;
let total_tests = 0;
let total_correct = 0;

// 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;


// Matrix.randomize() is changed to point to this. Must be defined by user of Matrix. 

function randomWeight()
{
    return ( AB.randomFloatAtoB ( -0.5, 0.5 ) );
            // Coding Train default is -1 to 1
}    



// CSS trick 
// make run header bigger 
 $("#runheaderbox").css ( { "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> 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='do_training = false;' class='normbutton' >Stop training</button> <br> ";
  AB.msg ( thehtml, 3 );
     
  // 4 variable training data 
  
  // 5 Testing header
  thehtml = "<h3> Hidden tests </h3> " ;
  AB.msg ( thehtml, 5 );
           
  // 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: ---------------------------------------------------------




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 ( "/uploads/codingtrain/matrix.js", function()
 {
 //  $.getScript ( "/uploads/codingtrain/nn.js", function()
 //  {
        $.getScript ( "/uploads/codingtrain/mnist.js", function()
        {
            console.log ("All JS loaded");
            nn = new NeuralNetwork(  noinput, nohidden, nooutput );
            nn.setLearningRate ( learningrate );
            loadData();
        });
//   });
 });
}



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

function loadData()    
{
  loadMNIST ( function(data)    
  {
    mnist = data;
    console.log ("All data loaded into mnist object:")
    console.log(mnist);
    AB.removeLoading();     // if no loading screen exists, this does nothing 
  });
}

function rotateImage ( img )      // make a P5 image object from a raw data array   
{
    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;
}

function getImage ( img )      // make a P5 image object from a raw data array   
{
    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;
}


function getInputs ( img )      // convert img array into normalised input array 
{
    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 trainit (show)        // train the network with a single exemplar, from global var "train_index", show visual on or off 
{
  let img   = mnist.train_images[train_index];
  let label = mnist.train_labels[train_index];
  
  // optional - show visual of the image 
  if (show)                
  {
    var theimage = getImage ( img );    // get image from data array 
    image ( theimage,   0,                ZOOMPIXELS+50,    ZOOMPIXELS,     ZOOMPIXELS  );      // magnified 
    image ( theimage,   ZOOMPIXELS+50,    ZOOMPIXELS+50,    PIXELS,         PIXELS      );      // original
    
    //rotate image ??
  }

  // set up the inputs
  let inputs = getInputs ( img );       // get inputs from data array 

  // set up the outputs
  let targets = [0, 0, 0, 0, 0, 0, 0, 0, 0, 0];
  targets[label] = 1;       // change one output location to 1, the rest stay at 0 

  // console.log(train_index);
  // console.log(inputs);
  // console.log(targets);

  train_inputs = inputs;        // can inspect in console 
  let inputs_copy = []
  //console.log("Input = " + inputs);
  
  let num_loop =0;
 
  while(inputs[num_loop]===0){
      num_loop++
  }
  
   //console.log("num_loop " + num_loop);
   
   for(let i = 0; i < PIXELSSQUARED; i++){
       inputs_copy[i] = 0;
   }
   let y = 0;
   
   for(let i = num_loop; i<PIXELSSQUARED;i++){
       inputs_copy[y] = inputs[num_loop];
       y++;
   }

  
  
  //fill first 56 places with 0
//  let inputs_move_right = [];
//    for (let i = 0; i < 56 ; i++) {
//     inputs_move_right[i] = 0;
//    }
  
  //fill next 56-727 places with 0-672 places from input 
//  for (let j = 56; j < PIXELSSQUARED ; j++) 
 // {
   //  let i = 0;    
//     inputs_move_right[j] = inputs[i];
 //    i++;
//  }
  //fill last 56 places 672-727 with 0
 //   let inputs_move_left = [];
 //   for (let i = PIXELSSQUARED - 56; i < PIXELSSQUARED ; i++) {
 //    inputs_move_left[i] = 0;
 //   }
  
  
//  for (let j = 0; j < PIXELSSQUARED - 56 ; j++) 
 // {
 //    let i = 56;    
 //    inputs_move_left[j] = inputs[i];
 //    i++;
 // }
  
  nn.train ( inputs_copy, targets );
//  nn.train ( inputs_move_right, targets );
//  nn.train ( inputs_move_left, targets );
  

  thehtml = " trainrun: " + trainrun + "<br> no: " + train_index ;
  AB.msg ( thehtml, 4 );

  train_index++;
  if ( train_index == NOTRAIN ) 
  {
    train_index = 0;
    console.log( "finished trainrun: " + trainrun );
    trainrun++;
  }
}


function testit()    // test the network with a single exemplar, from global var "test_index"
{ 
  let img   = mnist.test_images[test_index];
  let label = mnist.test_labels[test_index];

  // set up the inputs
  let inputs = getInputs ( img ); 
  
  test_inputs = inputs;        // can inspect in console 
  
  let inputs_copy = [];
  //console.log("Input = " + inputs);
  
  let num_loop =0;
 
  while(inputs[num_loop]===0){
      num_loop++;
  }
  
   //console.log("num_loop " + num_loop);
   
   for(let i = 0; i < PIXELSSQUARED; i++){
       inputs_copy[i] = 0;
   }
   
   let y = 0;
   for(let i = num_loop; i<PIXELSSQUARED;i++){
       inputs_copy[y] = inputs[num_loop];
       y++;
   }  
  
  
  let prediction    = nn.predict(inputs_copy);       // array of outputs 
  let guess         = findMax(prediction);      // the top output 

  total_tests++;
  if (guess == label)  total_correct++;

  let percent = (total_correct / total_tests) * 100 ;
  
  thehtml =  " testrun: " + testrun + "<br> no: " + total_tests + " <br> " +
        " correct: " + total_correct + "<br>" +
        "  score: " + greenspan + percent.toFixed(2) + "</span>";
  AB.msg ( thehtml, 6 );

  test_index++;
  if ( test_index == NOTEST ) 
  {
    console.log( "finished testrun: " + testrun + " score: " + percent.toFixed(2) );
    testrun++;
    test_index = 0;
    total_tests = 0;
    total_correct = 0;
  }
}




//--- find no.1 (and maybe no.2) output nodes ---------------------------------------
// (restriction) assumes array values start at 0 (which is true for output nodes) 


function find12 (a)         // return array showing indexes of no.1 and no.2 values in array 
{
  let no1 = 0;
  let no2 = 0;
  let no1value = 0;     
  let no2value = 0;
  
  for (let i = 0; i < a.length; i++) 
  {
    if (a[i] > no1value) 
    {
      no1 = i;
      no1value = a[i];
    }
    else if (a[i] > no2value) 
    {
      no2 = i;
      no2value = a[i];
    }
  }
  
  var b = [ no1, no2 ];
  return b;
}


// just get the maximum - separate function for speed - done many times 
// find our guess - the max of the output nodes array

function findMax (a)        
{
  let no1 = 0;
  let no1value = 0;     
  
  for (let i = 0; i < a.length; i++) 
  {
    if (a[i] > no1value) 
    {
      no1 = i;
      no1value = a[i];
    }
  }
  
  return no1;
}

function findMaxandValue (a)        
{
  let no1 = 0;
  let no1value = 0;     
  
  for (let i = 0; i < a.length; i++) 
  {
    if (a[i] > no1value) 
    {
      no1 = i;
      no1value = a[i];
    }
  }
  
  var b = [ no1, no1value ];
  return b;  
}




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


// 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 some testing per step 
    for (let i = 0; i < TESTPERSTEP; i++) 
      testit();
}

  // 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();
  }


// 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.");
            doodle.filter (BLUR, DOODLE_BLUR);    // just blur once 
            //   console.log (doodle);
      }
  }
}




//--- 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, NOTEST - 1 );  
    
    demo        = mnist.test_images[i];     
    var label   = mnist.test_labels[i];
    
   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 );
     //  console.log (theimage);
     
    image ( theimage,   0,                canvasheight - ZOOMPIXELS,    ZOOMPIXELS,     ZOOMPIXELS  );      // magnified 
    image ( theimage,   ZOOMPIXELS+50,    canvasheight - ZOOMPIXELS,    PIXELS,         PIXELS      );      // original
}


function guessDemo()
{
   let inputs = getInputs ( demo ); 
   
  demo_inputs = inputs;  // can inspect in console 
  
  let prediction    = nn.predict(inputs);       // array of outputs 
  let guess         = findMax(prediction);      // the top output 

   thehtml =   " We classify it as: " + greenspan + guess + "</span>" ;
   AB.msg ( thehtml, 9 );
}




//--- 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.loadPixels();

  // set up inputs   
  let inputs = [];
  for (let i = 0; i < PIXELSSQUARED ; i++) 
  {
     inputs[i] = img.pixels[i * 4] / 255;
  }
 // console.log(inputs);
  
 // let inputs_move_right = [];
 //   for (let i = 0; i < 56 ; i++) {
//     inputs_move_right[i] = 0;
  //  }
 // 
  //for (let j = 56; j < PIXELSSQUARED ; j++) 
  //{
  //   let i = 0;    
 //    inputs_move_right[j] = img.pixels[i * 4] / 255;
//     i++;
  //}
  
  doodle_inputs = inputs;     // can inspect in console 

  // feed forward to make prediction 
  let prediction    = nn.predict(inputs);       // array of outputs 
  let b             = find12(prediction);       // get no.1 and no.2 guesses  
  
  //let c = findMaxandValue(prediction);
  //console.log("Prediction " + c[0] + " " + c[1]);
  
  //let prediction_right = nn.predict(inputs_move_right);
  //let b_right = find12(prediction_right);
 // 
  //let d = findMaxandValue(prediction_right);
  //console.log("Right Prediction " + d[0] + " " + d[1]);
  
 // if(c[1]>d[1]){
   //   b[0] = c[0];
 // }else{
//      b[0] = d[0];
  //}
  
  //console.log("Right Prediction " + prediction_right);

  thehtml =   " We classify it as: " + greenspan + b[0] + "</span> <br>" +
            " No.2 guess is: " + greenspan + b[1] + "</span>";
//  thehtml_right =   " Right " + greenspan + b_right[0] + "</span> <br>" +
//            " No.2 Right: " + greenspan + b_right[1] + "</span>";            
  AB.msg ( thehtml, 2 );
 // AB.msg ( thehtml_right, 3 );
}


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




// --- debugging --------------------------------------------------
// in console
// showInputs(demo_inputs);
// showInputs(doodle_inputs);


function showInputs ( inputs )
// display inputs row by row, corresponding to square of pixels 
{
    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);
}

class ActivationFunction {
  constructor(func, dfunc) {
    this.func = func;
    this.dfunc = dfunc;
  }
}


let sigmoid = new ActivationFunction(
  x => 1 / (1 + Math.exp(-x)),
  y => y * (1 - y)
);

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

let tanh = new ActivationFunction(
  x => Math.tanh(x),
  y => 1 - (y * y)
);

let relu =  new ActivationFunction(
  x => Math.max(0,x),
  y => 1 - (y * y)
);

//let dsigmoid = new ActivationFunction(
//  x => sigmoid(x) * (1 - sigmoid(x)),
//  y => y * (1 - y)
//);

class NeuralNetwork {
  /*
  * if first argument is a NeuralNetwork the constructor clones it
  * USAGE: cloned_nn = new NeuralNetwork(to_clone_nn);
  */
  constructor(in_nodes, hid_nodes, out_nodes) {
    if (in_nodes instanceof NeuralNetwork) {
      let a = in_nodes;
      this.input_nodes = a.input_nodes;
      this.hidden_nodes = a.hidden_nodes;
      this.output_nodes = a.output_nodes;

      this.weights_ih = a.weights_ih.copy();
      this.weights_ho = a.weights_ho.copy();

      this.bias_h = a.bias_h.copy();
      this.bias_o = a.bias_o.copy();
    } else {
      this.input_nodes = in_nodes;
      this.hidden_nodes = hid_nodes;
      this.output_nodes = out_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();
    }

    // TODO: copy these as well
    this.setLearningRate();
    this.setActivationFunction();


  }

  predict(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(this.activation_function.func);

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

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

  setLearningRate(learning_rate = 0.1) {
    this.learning_rate = learning_rate;
  }

  setActivationFunction(func = sigmoid) {
    this.activation_function = func;
  }

  train(input_array, target_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(this.activation_function.func);

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

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

    // Calculate the error
    // ERROR = TARGETS - OUTPUTS
    let output_errors = Matrix.subtract(targets, outputs);

    // let gradient = outputs * (1 - outputs);
    // Calculate gradient
    let gradients = Matrix.map(outputs, this.activation_function.dfunc);
    gradients.multiply(output_errors);
    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, this.activation_function.dfunc);
    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();
  }

  serialize() {
    return JSON.stringify(this);
  }

  static deserialize(data) {
    if (typeof data == 'string') {
      data = JSON.parse(data);
    }
    let nn = new NeuralNetwork(data.input_nodes, data.hidden_nodes, data.output_nodes);
    nn.weights_ih = Matrix.deserialize(data.weights_ih);
    nn.weights_ho = Matrix.deserialize(data.weights_ho);
    nn.bias_h = Matrix.deserialize(data.bias_h);
    nn.bias_o = Matrix.deserialize(data.bias_o);
    nn.learning_rate = data.learning_rate;
    return nn;
  }


  // Adding function for neuro-evolution
  copy() {
    return new NeuralNetwork(this);
  }

  // Accept an arbitrary function for mutation
  mutate(func) {
    this.weights_ih.map(func);
    this.weights_ho.map(func);
    this.bias_h.map(func);
    this.bias_o.map(func);
  }



}