Base64 hybrid method (v7)

Revision 7 of this benchmark created by Xotic750 on March 15, 2013

Preparation HTML

<script src="//utility-js.googlecode.com/files/utility3.js"></script>

Setup

var txt = "You might assume from this that I couldn't give a rat's ass about these miserably inept crapmobile makers down the road in Detroit city. But I do care. I care about the millions whose lives and livelihoods depend on these car companies. I care about the security and defense of this country because the world is running out of oil -- and when it runs out, the calamity and collapse that will take place will make the current recession/depression look like a Tommy Tune musical.";
    
    function hybrid_encode(txt) {
      if (typeof(btoa) === 'function') {
        return btoa(txt);
      } else {
        return Base64.encode(txt);
      }
    }
    
    function hybrid_encode_prop(txt) {
      if ('btoa' in window) {
        return btoa(txt);
      } else {
        return Base64.encode(txt);
      }
    }
    if (window.btoa) {
      hybrid_encode_less_ifs = btoa;
    } else {
      hybrid_encode_less_ifs = function(txt) {
        return Base64.encode(txt);
      };
    }
    
    
    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;
      }
    
    }

Test runner

var out = Base64.encode(txt);

var out = btoa(txt);

var out = hybrid_encode(txt);

var out = hybrid_encode_prop(txt);

var out = hybrid_encode_less_ifs(txt);

var out = $u.btoa(txt);

Revisions

You can edit these tests or add more tests to this page by appending /edit to the URL.

• Revision 1: published by Scott Baker on June 21, 2011
• Revision 2: published on October 23, 2012
• Revision 3: published by Joel Hillacre on January 14, 2013
• Revision 4: published by Xotic750 on March 11, 2013
• Revision 5: published by Xotic750 on March 12, 2013
• Revision 6: published by Xotic750 on March 12, 2013
• Revision 7: published by Xotic750 on March 15, 2013