根据浏览器信息
生成浏览器唯一识别码

转自： 点赞需求使用canvas fingerprinting（画布指纹追踪）的过程

function bin2hex(s) {
            var i, l, o = '', n;
            s += '';
            for (i = 0, l = s.length; i < l; i++) {
                n = s.charCodeAt(i).toString(16);
                o += n.length < 2 ? '0' + n : n;
            }
            return o;
        }

        function getUUID(domain) {
            var canvas = document.createElement('canvas');
            var ctx = canvas.getContext("2d");
            ctx.font = "24px Arial";
            ctx.fillText("Hello Panda", 22, 33);
            ctx.moveTo(0, 60);
            ctx.lineTo(100, 60);
            ctx.stroke();
            var b64 = canvas.toDataURL().replace("data:image/png;base64,","");
            var bin = atob(b64);
            var crc = bin2hex(bin.slice(-16, -12));
            return crc;
        }
        console.log(getUUID("chenxiaomo"));