remoting/webapp/connection_stats.js

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 /**
   6  * @fileoverview
   7  * Module to support debug overlay window with connection stats.
   8  */
   9
  10 'use strict';
  11
  12 /** @suppress {duplicate} */
  13 var remoting = remoting || {};
  14
  15 /**
  16  * @constructor
  17  * @param {Element} statsElement The HTML div to which to update stats.
  18  */
  19 remoting.ConnectionStats = function(statsElement) {
  20   this.statsElement = statsElement;
  21 };
  22
  23 /**
  24  * Show or hide the connection stats div.
  25  */
  26 remoting.ConnectionStats.prototype.toggle = function() {
  27   this.statsElement.hidden = !this.statsElement.hidden;
  28 };
  29
  30 /**
  31  * Update the statistics panel.
  32  * @param {remoting.ClientSession.PerfStats} stats The connection statistics.
  33  */
  34 remoting.ConnectionStats.prototype.update = function(stats) {
  35   var units = '';
  36   var videoBandwidth = stats.videoBandwidth;
  37   if (videoBandwidth != undefined) {
  38     if (videoBandwidth < 1024) {
  39       units = 'Bps';
  40     } else if (videoBandwidth < 1048576) {
  41       units = 'KiBps';
  42       videoBandwidth = videoBandwidth / 1024;
  43     } else if (videoBandwidth < 1073741824) {
  44       units = 'MiBps';
  45       videoBandwidth = videoBandwidth / 1048576;
  46     } else {
  47       units = 'GiBps';
  48       videoBandwidth = videoBandwidth / 1073741824;
  49     }
  50   }
  51
  52   /**
  53    * @param {number} value
  54    * @param {string} units
  55    * @return {string} Formatted number.
  56    */
  57   function formatStatNumber(value, units) {
  58     if (value != undefined) {
  59       return value.toFixed(2) + ' ' + units;
  60     } else {
  61       return "n/a";
  62     }
  63   }
  64
  65   var statistics = document.getElementById('statistics');
  66   this.statsElement.innerText = (
  67       'Bandwidth: ' + formatStatNumber(videoBandwidth, units) +
  68       ', Frame Rate: ' + formatStatNumber(stats.videoFrameRate, 'fps') +
  69       ', Capture: ' + formatStatNumber(stats.captureLatency, 'ms') +
  70       ', Encode: ' + formatStatNumber(stats.encodeLatency, 'ms') +
  71       ', Decode: ' + formatStatNumber(stats.decodeLatency, 'ms') +
  72       ', Render: ' + formatStatNumber(stats.renderLatency, 'ms') +
  73       ', Latency: ' + formatStatNumber(stats.roundtripLatency, 'ms'));
  74 };
  75
  76 /**
  77  * Check for the debug toggle hot-key.
  78  *
  79  * @param {Event} event The keyboard event.
  80  * @return {void} Nothing.
  81  */
  82 remoting.ConnectionStats.onKeydown = function(event) {
  83   var element = /** @type {Element} */ (event.target);
  84   if (element.tagName == 'INPUT' || element.tagName == 'TEXTAREA') {
  85     return;
  86   }
  87   if (String.fromCharCode(event.which) == 'D') {
  88     remoting.stats.toggle();
  89   }
  90 };
  91
  92 /** @type {remoting.ConnectionStats} */
  93 remoting.stats = null;