https://sibylleomlin.com/wp-content/themes/solofolio/js/lazy-load.js?ver=7.0.73

1/*global jQuery */
2/*!
3* SoloFolio Lazy Load JS
4*
5* By Luis Almeida
6* https://github.com/luis-almeida/unveil
7*/
8;(function($) {
9
10  $.fn.unveil = function(threshold, callback) {
11
12    var $w = $(window),
13        th = threshold || 0,
14        retina = window.devicePixelRatio > 1,
15        attrib = retina? "data-src-retina" : "data-src",
16        images = this,
17        loaded;
18
19    this.one("unveil", function() {
20      var source = this.getAttribute(attrib);
21      source = source || this.getAttribute("data-src");
22      if (source) {
23        this.setAttribute("src", source);
24        if (typeof callback === "function") callback.call(this);
25      }
26    });
27
28    function unveil() {
29      var inview = images.filter(function() {
30        var $e = $(this);
31        if ($e.is(":hidden")) return;
32
33        var wt = $w.scrollTop(),
34            wb = wt + $w.height(),
35            et = $e.offset().top,
36            eb = et + $e.height();
37
38        return eb >= wt - th && et <= wb + th;
39      });
40
41      loaded = inview.trigger("unveil");
42      images = images.not(loaded);
43    }
44
45    $w.on("scroll.unveil resize.unveil lookup.unveil", unveil);
46
47    unveil();
48
49    return this;
50
51  };
52
53})(window.jQuery);