instagram_preview.js

function ig_media_preview(base64data) {
	var jpegtpl = "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",
		t = atob(base64data),
		p = t.slice(3).split(""),
		o = t.substring(0, 3).split("").map(function(e) {
			return e.charCodeAt(0)
		}),
		c = atob(jpegtpl).split("");
	c[162] = String.fromCharCode(o[1]);
	c[160] = String.fromCharCode(o[2]);
	return base64data ? "data:image/jpeg;base64," + btoa(c.concat(p).join("")) : null
};
      
var data = "ACoqxAKmSPeeenWmZAq41uRgEjBAPPTPP+NQ2XFXZMkK44A/KmG3BDFAMqM1EI3XIQjn72OR+HvipoIWXcUIB2kcc7gf8/h1qPmaPbYpplutWfKNNiYDsTV4TDH3f1/+tW9jnIFtYx1Yn/gNas8SeUHXtgH249O1WbgxKp37QAvGcetYd3fITti6HG4+oHT8uv6VkzREDHn0+hxVgO0aHoC/yj+ZP+fWqhds9Mj1q5HPGzqkqgrjGeeDn2PT196S31Lk9NAt4smtQWw9KkSKNOgxnpwf61a3KO9dF+xztHCSzvKdzksfeos0lJWZRcglz8p69qmdhuA9Ov8AhWevWpVqbal30sdDHfsqcnPoD6f56VW+2A85b9KoKetNqrkn/9k=";
var uri = ig_media_preview(data);
document.body.insertAdjacentHTML('beforeend', '<img src="' + uri + '">');