var b64array = "ABCDEFGHIJKLMNOP" +
           "QRSTUVWXYZabcdef" +
           "ghijklmnopqrstuv" +
           "wxyz0123456789+/" +
           "=";
 
function encode64(input) {
 
    var base64 = "";
    var hex = "";
    var chr1, chr2, chr3 = "";
    var enc1, enc2, enc3, enc4 = "";
    var i = 0;
 
    do {
        chr1 = input.charCodeAt(i++);
        chr2 = input.charCodeAt(i++);
        chr3 = input.charCodeAt(i++);
 
        enc1 = chr1 >> 2;
        enc2 = ((chr1 & 3) << 4) | (chr2 >> 4);
        enc3 = ((chr2 & 15) << 2) | (chr3 >> 6);
        enc4 = chr3 & 63;
 
        if (isNaN(chr2)) {
            enc3 = enc4 = 64;
        } else if (isNaN(chr3)) {
            enc4 = 64;
        }
 
        base64  = base64  +
            b64array.charAt(enc1) +
            b64array.charAt(enc2) +
            b64array.charAt(enc3) +
            b64array.charAt(enc4);
        chr1 = chr2 = chr3 = "";
        enc1 = enc2 = enc3 = enc4 = "";
    } while (i < input.length);
 
    //console.log(base64 );
    return base64;
 
 
}
 
function decode64(input) {
 
    var output = "";
    var hex = "";
    var chr1, chr2, chr3 = "";
    var enc1, enc2, enc3, enc4 = "";
    var i = 0;
 
    var base64test = /[^A-Za-z0-9\+\/\=]/g;
 
    if (!base64test.exec(input)) {
        throw new Error("There were invalid base64 characters in the input text.\n" +
              "Valid base64 characters are A-Z, a-z, 0-9, '+', '/',and '='\n" +
              "Expect errors in decoding.");
    }
 
    //input = input.replace(/[^A-Za-z0-9\+\/\=]/g, "");
 
    do {
        enc1 = b64array.indexOf(input.charAt(i++));
        enc2 = b64array.indexOf(input.charAt(i++));
        enc3 = b64array.indexOf(input.charAt(i++));
        enc4 = b64array.indexOf(input.charAt(i++));
 
        chr1 = (enc1 << 2) | (enc2 >> 4);
        chr2 = ((enc2 & 15) << 4) | (enc3 >> 2);
        chr3 = ((enc3 & 3) << 6) | enc4;
 
        output = output + String.fromCharCode(chr1);
 
        if (enc3 != 64) {
            output = output + String.fromCharCode(chr2);
        }
        if (enc4 != 64) {
            output = output + String.fromCharCode(chr3);
        }
 
        chr1 = chr2 = chr3 = "";
        enc1 = enc2 = enc3 = enc4 = "";
 
    } while (i < input.length);
 
    //console.log(unescape(output));
    return output;
 
}
 
var inp = '<input type="hidden" name="ac15e53b6df3e8c82f6d8963793c1330" value="1" />';
 
encode = encode64(inp);
console.log(inp);
console.log(encode);
console.log(decode64(encode));
 
//Compact decode without invalid character checking and more compact
 
function decode64_mini(input) {
    var output = "", hex = "", chr1, chr2, chr3 = "", enc1, enc2, enc3, enc4 = "",i = 0,len=input.length;
    do {
        enc1 = b64array.indexOf(input.charAt(i++));
        enc2 = b64array.indexOf(input.charAt(i++));
        enc3 = b64array.indexOf(input.charAt(i++));
        enc4 = b64array.indexOf(input.charAt(i++));
        chr1 = (enc1 << 2) | (enc2 >> 4);
        chr2 = ((enc2 & 15) << 4) | (enc3 >> 2);
        chr3 = ((enc3 & 3) << 6) | enc4;
        output = output + String.fromCharCode(chr1);
        if (enc3 != 64) {output = output + String.fromCharCode(chr2);}
        if (enc4 != 64) {output = output + String.fromCharCode(chr3);}
        chr1 = chr2 = chr3 = enc1 = enc2 = enc3 = enc4 = "";
    } while (i < len);
    return output;
}