function decode_base64 (encStr) {
  
  	var base64s = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/';
    var bits, decOut = '', i = 0; 
    for(; i<encStr.length; i += 4){ 
      bits = 
       (base64s.indexOf(encStr.charAt(i))    & 0xff) <<18 | 
       (base64s.indexOf(encStr.charAt(i +1)) & 0xff) <<12 | 
       (base64s.indexOf(encStr.charAt(i +2)) & 0xff) << 6 | 
        base64s.indexOf(encStr.charAt(i +3)) & 0xff; 
      decOut += String.fromCharCode( 
       (bits & 0xff0000) >>16, (bits & 0xff00) >>8, bits & 0xff); 
      } 
			
      if(encStr.charCodeAt(i -2) == 61) 
        undecOut=decOut.substring(0, decOut.length -2); 
      else if(encStr.charCodeAt(i -1) == 61) 
        undecOut=decOut.substring(0, decOut.length -1); 
      else undecOut=decOut; 
  
  
    return unescape(undecOut);
	
}
		
  function encode_base64(decStr) {
	
    var base64s = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/';
    var bits;
    var dual;
    var i = 0;
    var encOut = '';
    while(decStr.length >= i + 3) {
    
    bits = (decStr.charCodeAt(i++) & 0xff) <<16 |
           (decStr.charCodeAt(i++) & 0xff) <<8  |
            decStr.charCodeAt(i++) & 0xff;
    encOut += base64s.charAt((bits & 0x00fc0000) >>18) +
              base64s.charAt((bits & 0x0003f000) >>12) +
              base64s.charAt((bits & 0x00000fc0) >> 6) +
              base64s.charAt((bits & 0x0000003f));
    }
    
    if(decStr.length -i > 0 && decStr.length -i < 3) {
    
    dual = Boolean(decStr.length -i -1);
    bits = ((decStr.charCodeAt(i++) & 0xff) <<16) |
           (dual ? (decStr.charCodeAt(i) & 0xff) <<8 : 0);
    encOut += base64s.charAt((bits & 0x00fc0000) >>18) +
              base64s.charAt((bits & 0x0003f000) >>12) +
              (dual ? base64s.charAt((bits & 0x00000fc0)             >>6) : '=') +
              '=';
    }
    
    return(encOut);
	
	}