var keyStr = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=";

   function encode64(input) {
				var output = "";
				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;
							}

							output = output + keyStr.charAt(enc1) + keyStr.charAt(enc2) +
										keyStr.charAt(enc3) + keyStr.charAt(enc4);
				} while (i < input.length);

				return output;
  }

  function decode64(input) {
   var output = "";
   var chr1, chr2, chr3;
   var enc1, enc2, enc3, enc4;
   var i = 0;

    input = input.replace(/[^A-Za-z0-9\+\/\=]/g, "");

				do {
							enc1 = keyStr.indexOf(input.charAt(i++));
							enc2 = keyStr.indexOf(input.charAt(i++));
							enc3 = keyStr.indexOf(input.charAt(i++));
							enc4 = keyStr.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);
							}
				} while (i < input.length);
				return output;
	  }