upload progress and speed

upload_progress.js

      var loadedFromTotal = event.loaded / event.total;
      var percent = 100.0 * loadedFromTotal;
      var chunk = (loadedFromTotal) * event.total;
      var speed = ((chunk / 1024 / 1024) / time).toFixed(2);
      var secs_left = parseInt((100 / percent) * time) - time;
      var seconds_left = isFinite(secs_left) ? secs_left : 60*60*100;

/////////////////////////////////////////////////////////////////////////////
//  time
////////////////////////////////////////////////////////////////////////////
file.started = Date.now();

_e_.add({
    name: fileKey,
    file: file,
    xAmzHeadersAtInitiate: {
        'x-amz-acl': 'public-read'
    },
    complete: function() {
        file.completed = true;
    },
    progress: function(progress) {

        // returns percent / 100 with 2 decimal places I.E (10.00)
        file.progress = (Math.round((progress * 100) * 100) / 100);

        var currentTime            = Date.now();
        var progressRemaining      = (100 - file.progress);
        var progressionRate        = (progressRemaining / file.progress);
        var timeToCurrentPosition  = (currentTime - file.started);

        // return seconds left during download
        file.timeLeft = Math.round((progressionRate * timeToCurrentPosition) / 1000);

    }
});


/////////////////////////////////////////////////////////////////////////////////////////
// speed
////////////////////////////////////

progress *= 100;
progress = progress.toFixed(2);

var delta = (new Date() - fileStartTime) / 1000;

var loaded = (progress * fileSize) / 100;

var totalSentBySecond = loaded / delta;          

var speed = readableFileSize(totalSentBySecond) + '/s';

function readableFileSize(size) 
  {
      var units = ['B', 'KB', 'MB', 'GB', 'TB', 'PB', 'EB', 'ZB', 'YB'];
      var i = 0;

      while(size >= 1024) 
      {
          size /= 1024;
          ++i;
      }

      return size.toFixed(2).replace('.00', '') + ' ' + units[i];
  }