Lazy Load Comparision (v2)

Revision 2 of this benchmark created on


Preparation HTML

<script src="//ajax.googleapis.com/ajax/libs/jquery/1/jquery.min.js"></script>
<div id="lazy_load">
  <img src="http://stage.bibliocms.com/wp-content/themes/bibliocommons/images/building.png" data-original="http://upload.wikimedia.org/wikipedia/en/thumb/4/4a/Image-Chagall_Fiddler.jpg/499px-Image-Chagall_Fiddler.jpg" />

  <img src="http://stage.bibliocms.com/wp-content/themes/bibliocommons/images/building.png" data-original="http://artmodel.files.wordpress.com/2009/05/chagall-promenade.jpeg" />


  <img src="http://stage.bibliocms.com/wp-content/themes/bibliocommons/images/building.png" data-original="http://upload.wikimedia.org/wikipedia/en/thumb/4/4a/Image-Chagall_Fiddler.jpg/499px-Image-Chagall_Fiddler.jpg" />


  <img src="http://stage.bibliocms.com/wp-content/themes/bibliocommons/images/building.png" data-original="http://3.bp.blogspot.com/_NT2qYHHyMZA/TP1KdiHGpbI/AAAAAAAAB5Q/ajZj6lHYtLI/s1600/chagall01a.jpg" />


  <img src="http://stage.bibliocms.com/wp-content/themes/bibliocommons/images/building.png" data-original="http://www.moma.org/collection_images/resized/186/w500h420/CRI_151186.jpg" />

</div>
<div id="unveil">

  <img src="http://stage.bibliocms.com/wp-content/themes/bibliocommons/images/building.png" data-original="http://upload.wikimedia.org/wikipedia/en/thumb/4/4a/Image-Chagall_Fiddler.jpg/499px-Image-Chagall_Fiddler.jpg" />

  <img src="http://stage.bibliocms.com/wp-content/themes/bibliocommons/images/building.png" data-original="http://artmodel.files.wordpress.com/2009/05/chagall-promenade.jpeg" />

  <img src="http://stage.bibliocms.com/wp-content/themes/bibliocommons/images/building.png" data-original="http://upload.wikimedia.org/wikipedia/en/thumb/4/4a/Image-Chagall_Fiddler.jpg/499px-Image-Chagall_Fiddler.jpg" />

  <img src="http://stage.bibliocms.com/wp-content/themes/bibliocommons/images/building.png" data-original="http://3.bp.blogspot.com/_NT2qYHHyMZA/TP1KdiHGpbI/AAAAAAAAB5Q/ajZj6lHYtLI/s1600/chagall01a.jpg" />

  <img src="http://stage.bibliocms.com/wp-content/themes/bibliocommons/images/building.png" data-original="http://www.moma.org/collection_images/resized/186/w500h420/CRI_151186.jpg" />
</div>

Setup

/*
     * Lazy Load - jQuery plugin for lazy loading images
     *
     * Copyright (c) 2007-2013 Mika Tuupola
     *
     * Licensed under the MIT license:
     *   http://www.opensource.org/licenses/mit-license.php
     *
     * Project home:
     *   http://www.appelsiini.net/projects/lazyload
     *
     * Version:  1.9.3
     *
     */
    
    (function($, window, document, undefined) {
      var $window = $(window);
    
      $.fn.lazyload = function(options) {
        var elements = this;
        var $container;
        var settings = {
          threshold       : 0,
          failure_limit   : 0,
          event           : "scroll",
          effect          : "show",
          container       : window,
          data_attribute  : "original",
          skip_invisible  : true,
          appear          : null,
          load            : null,
          placeholder     : "data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB/AAffA0nNPuCLAAAAAElFTkSuQmCC"
        };
    
        function update() {
          var counter = 0;
    
          elements.each(function() {
            var $this = $(this);
            if (settings.skip_invisible && !$this.is(":visible")) {
              return;
            }
            if ($.abovethetop(this, settings) ||
              $.leftofbegin(this, settings)) {
              /* Nothing. */
            } else if (!$.belowthefold(this, settings) &&
              !$.rightoffold(this, settings)) {
              $this.trigger("appear");
              /* if we found an image we'll load, reset the counter */
              counter = 0;
            } else {
              if (++counter > settings.failure_limit) {
                return false;
              }
            }
          });
    
        }
    
        if(options) {
          /* Maintain BC for a couple of versions. */
          if (undefined !== options.failurelimit) {
            options.failure_limit = options.failurelimit;
            delete options.failurelimit;
          }
          if (undefined !== options.effectspeed) {
            options.effect_speed = options.effectspeed;
            delete options.effectspeed;
          }
    
          $.extend(settings, options);
        }
    
        /* Cache container as jQuery as object. */
        $container = (settings.container === undefined ||
          settings.container === window) ? $window : $(settings.container);
    
        /* Fire one scroll event per scroll. Not one scroll event per image. */
        if (0 === settings.event.indexOf("scroll")) {
          $container.bind(settings.event, function() {
            return update();
          });
        }
    
        this.each(function() {
          var self = this;
          var $self = $(self);
    
          self.loaded = false;
    
          /* If no src attribute given use data:uri. */
          if ($self.attr("src") === undefined || $self.attr("src") === false) {
            if ($self.is("img")) {
              $self.attr("src", settings.placeholder);
            }
          }
    
          /* When appear is triggered load original image. */
          $self.one("appear", function() {
            if (!this.loaded) {
              if (settings.appear) {
                var elements_left = elements.length;
                settings.appear.call(self, elements_left, settings);
              }
              $("<img />")
                .bind("load", function() {
    
                  var original = $self.attr("data-" + settings.data_attribute);
                  $self.hide();
                  if ($self.is("img")) {
                    $self.attr("src", original);
                  } else {
                    $self.css("background-image", "url('" + original + "')");
                  }
                  $self[settings.effect](settings.effect_speed);
    
                  self.loaded = true;
    
                  /* Remove image from array so it is not looped next time. */
                  var temp = $.grep(elements, function(element) {
                    return !element.loaded;
                  });
                  elements = $(temp);
    
                  if (settings.load) {
                    var elements_left = elements.length;
                    settings.load.call(self, elements_left, settings);
                  }
                })
                .attr("src", $self.attr("data-" + settings.data_attribute));
            }
          });
    
          /* When wanted event is triggered load original image */
          /* by triggering appear.                              */
          if (0 !== settings.event.indexOf("scroll")) {
            $self.bind(settings.event, function() {
              if (!self.loaded) {
                $self.trigger("appear");
              }
            });
          }
        });
    
        /* Check if something appears when window is resized. */
        $window.bind("resize", function() {
          update();
        });
    
        /* With IOS5 force loading images when navigating with back button. */
        /* Non optimal workaround. */
        if ((/(?:iphone|ipod|ipad).*os 5/gi).test(navigator.appVersion)) {
          $window.bind("pageshow", function(event) {
            if (event.originalEvent && event.originalEvent.persisted) {
              elements.each(function() {
                $(this).trigger("appear");
              });
            }
          });
        }
    
        /* Force initial check if images should appear. */
        $(document).ready(function() {
          update();
        });
    
        return this;
      };
    
      /* Convenience methods in jQuery namespace.           */
      /* Use as  $.belowthefold(element, {threshold : 100, container : window}) */
    
      $.belowthefold = function(element, settings) {
        var fold;
    
        if (settings.container === undefined || settings.container === window) {
          fold = (window.innerHeight ? window.innerHeight : $window.height()) + $window.scrollTop();
        } else {
          fold = $(settings.container).offset().top + $(settings.container).height();
        }
    
        return fold <= $(element).offset().top - settings.threshold;
      };
    
      $.rightoffold = function(element, settings) {
        var fold;
    
        if (settings.container === undefined || settings.container === window) {
          fold = $window.width() + $window.scrollLeft();
        } else {
          fold = $(settings.container).offset().left + $(settings.container).width();
        }
    
        return fold <= $(element).offset().left - settings.threshold;
      };
    
      $.abovethetop = function(element, settings) {
        var fold;
    
        if (settings.container === undefined || settings.container === window) {
          fold = $window.scrollTop();
        } else {
          fold = $(settings.container).offset().top;
        }
    
        return fold >= $(element).offset().top + settings.threshold  + $(element).height();
      };
    
      $.leftofbegin = function(element, settings) {
        var fold;
    
        if (settings.container === undefined || settings.container === window) {
          fold = $window.scrollLeft();
        } else {
          fold = $(settings.container).offset().left;
        }
    
        return fold >= $(element).offset().left + settings.threshold + $(element).width();
      };
    
      $.inviewport = function(element, settings) {
        return !$.rightoffold(element, settings) && !$.leftofbegin(element, settings) &&
          !$.belowthefold(element, settings) && !$.abovethetop(element, settings);
      };
    
      /* Custom selectors for your convenience.   */
      /* Use as $("img:below-the-fold").something() or */
      /* $("img").filter(":below-the-fold").something() which is faster */
    
      $.extend($.expr[":"], {
        "below-the-fold" : function(a) { return $.belowthefold(a, {threshold : 0}); },
        "above-the-top"  : function(a) { return !$.belowthefold(a, {threshold : 0}); },
        "right-of-screen": function(a) { return $.rightoffold(a, {threshold : 0}); },
        "left-of-screen" : function(a) { return !$.rightoffold(a, {threshold : 0}); },
        "in-viewport"    : function(a) { return $.inviewport(a, {threshold : 0}); },
        /* Maintain BC for couple of versions. */
        "above-the-fold" : function(a) { return !$.belowthefold(a, {threshold : 0}); },
        "right-of-fold"  : function(a) { return $.rightoffold(a, {threshold : 0}); },
        "left-of-fold"   : function(a) { return !$.rightoffold(a, {threshold : 0}); }
      });
    
    })(jQuery, window, document);

Test runner

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Testing in
TestOps/sec
lazy load single
$('div#lazy_load img').lazyload();
 
ready
LazyLoad loop

$('div#lazy_load img').each(function() {
    var $self = $(this);
    $self.lazyload();
});
ready

Revisions

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