Cara mempercepat loading foto atau gambar di blog

Credit img: freepik.com

Mempunyai banyak tampilan gambar atau foto di template blog sangatlah mempengaruhi kecepatan loading blog , baik untuk SEO maupun kenyamanan pembaca blog. Hal ini bisa diatasi dengan memasang kode script di bawah ini untuk mempercepat loading gambar blog itu:

<script type='text/javascript'>
//<![CDATA[
/*
* Lazy Load - jQuery plugin for lazy loading images
* Copyright (c) 2007-2012 Mika Tuupola
* Project home: http://www.appelsiini.net/projects/lazyload Version:  1.8.3
* Republished by Lukman Solichin www.lukman-s.blogspot.com
*/
(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
        };
        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(event) {
                return update();
            });
        }
        this.each(function() {
            var self = this;
            var $self = $(self);
            self.loaded = false;
            /* 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() {
                            $self
                                .hide()
                                .attr("src", $self.data(settings.data_attribute))
                                [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.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(event) {
                    if (!self.loaded) {
                        $self.trigger("appear");
                    }
                });
            }
        });
        /* Check if something appears when window is resized. */
        $window.bind("resize", function(event) {
            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.persisted) {
                    elements.each(function() {
                        $(this).trigger("appear");
                    });
                }
            });
        }
        /* Force initial check if images should appear. */
        $(window).load(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.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}); }
    });
//]]>
</script>
<script charset='utf-8' type='text/javascript'>
$(function() {
   $(&quot;img&quot;).lazyload({placeholder : &quot;https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhRgz7RZK0ivLNwP1bE35YpcK1n8FR5i2eG1fa-T49puhyphenhyphenj5V88m8OwRgNJiMZ_s8Q4oamJMZUfxeDerjNn2P3HJRCVyq0ZTKKCZErnyHVAQKXp5coyliUOuGvacL4a4LVq3_k75RQrwdE/s1600/grey.gif&quot;,threshold : 200});
});
</script>

 
Kemudian taruh kode script di atas kode </head> dan simpan.

Kode ini mendukung banyak browser, seperti firefox, chrome,dsb. Script Lazy Load Image ini dapat meningkatkan kinerja gambar postingan blog, thumbnail ataupun konten iframe. Jadi alangkah baiknya jika blog anda mempunyai banyak gambar ataupun foto, pasang juga kode script ini template blog anda juga agar pengunjung bisa lebih nyaman dengan kecepatan blog anda. 

Sekian dulu postingan yang berjudul Cara mempercepat loading foto atau gambar di blog ini, Semoga bisa bermanfaat.