artesanias/node_modules/localforage/bower_components/modernizr/feature-detects/img-apng.js

// Animated PNG
// http://en.wikipedia.org/wiki/APNG
// By Addy Osmani
(function () {

    if (!Modernizr.canvas) return false;
    
    var image = new Image(),
        canvas = document.createElement('canvas'),
        ctx = canvas.getContext('2d');


    image.onload = function () {
        Modernizr.addTest('apng', function () {
            if (typeof canvas.getContext == 'undefined') {
                return false;
            } else {
                ctx.drawImage(image, 0, 0);
                return ctx.getImageData(0, 0, 1, 1).data[3] === 0;
            }
        });
    };

    image.src = "data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAACGFjVEwAAAABAAAAAcMq2TYAAAANSURBVAiZY2BgYPgPAAEEAQB9ssjfAAAAGmZjVEwAAAAAAAAAAQAAAAEAAAAAAAAAAAD6A+gBAbNU+2sAAAARZmRBVAAAAAEImWNgYGBgAAAABQAB6MzFdgAAAABJRU5ErkJggg==";

}());