var Base64 = {  
	// private property  
	_keyStr : "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=",  
	// public method for encoding  
	encode : function (input) {  
		var output = "";  
		var chr1, chr2, chr3, enc1, enc2, enc3, enc4;  
		var i = 0;  
		input = Base64._utf8_encode(input);  
		while (i < input.length) {  
			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 +  
			this._keyStr.charAt(enc1) + this._keyStr.charAt(enc2) +  
			this._keyStr.charAt(enc3) + this._keyStr.charAt(enc4);  
   
		}
   
		return output;  
	},  
   
	 // public method for decoding  
	decode : function (input) {  
		var output = "";  
		var chr1, chr2, chr3;  
		var enc1, enc2, enc3, enc4;  
		var i = 0;  
   
		input = input.replace(/[^A-Za-z0-9\+\/\=]/g, "");  
   
		while (i < input.length) {  
   
			enc1 = this._keyStr.indexOf(input.charAt(i++));  
			enc2 = this._keyStr.indexOf(input.charAt(i++));  
			enc3 = this._keyStr.indexOf(input.charAt(i++));  
			enc4 = this._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);  
			}
   
		}
   
		output = Base64._utf8_decode(output);  
   
		return output;  
   
	},
	// private method for UTF-8 encoding  
	 _utf8_encode : function (string) {  
		string = string.replace(/\r\n/g,"\n");  
		var utftext = "";  
   
		for (var n = 0; n < string.length; n++) {  
   
			var c = string.charCodeAt(n);  
   
			if (c < 128) {  
				utftext += String.fromCharCode(c);  
			}  
			else if((c > 127) && (c < 2048)) {  
				utftext += String.fromCharCode((c >> 6) | 192);  
				utftext += String.fromCharCode((c & 63) | 128);  
			}  
			else {  
				utftext += String.fromCharCode((c >> 12) | 224);  
				utftext += String.fromCharCode(((c >> 6) & 63) | 128);  
				utftext += String.fromCharCode((c & 63) | 128);  
			}  
   
		}  
   
		return utftext;  
	},  
   
	 // private method for UTF-8 decoding  
	_utf8_decode : function (utftext) {  
		var string = "";  
		var i = 0;  
		var c = c1 = c2 = 0;
		
		while ( i < utftext.length ) {  
			
			c = utftext.charCodeAt(i);
			
			if (c < 128) {  
				string += String.fromCharCode(c);  
				i++;  
			}  
			else if((c > 191) && (c < 224)) {  
				c2 = utftext.charCodeAt(i+1);  
				string += String.fromCharCode(((c & 31) << 6) | (c2 & 63));  
				i += 2;  
			}  
			else {  
				c2 = utftext.charCodeAt(i+1);  
				c3 = utftext.charCodeAt(i+2);  
				string += String.fromCharCode(((c & 15) << 12) | ((c2 & 63) << 6) | (c3 & 63));
				i += 3;  
			}
			
		}
		return string;  
	}
}