Base64 decoder with UTF-8 decode of encoded ascii - unBase64 Button function for http://www.whak.ca/packer/LZW(HAK).htm

base64-decoder-utf.js

function a2b(r) {
  function utf(r) {
    for (var t = "", e = 0, o = c1 = c2 = 0; e < r.length; ) o = r.charCodeAt(e), 128 > o ? (t += String.fromCharCode(o), 
    e++) :o > 191 && 224 > o ? (c2 = r.charCodeAt(e + 1), t += String.fromCharCode((31 & o) << 6 | 63 & c2), 
    e += 2) :(c2 = r.charCodeAt(e + 1), c3 = r.charCodeAt(e + 2), t += String.fromCharCode((15 & o) << 12 | (63 & c2) << 6 | 63 & c3), 
    e += 3);
    return t;
  }
  var t, X = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=", e, o, a, h, n = "", c = 0;
  for (r = r.replace(/[^A-Za-z0-9\+\/\=]/g, ""); c < r.length; ) t = X.indexOf(r.charAt(c++)), 
  e = X.indexOf(r.charAt(c++)), a = X.indexOf(r.charAt(c++)), h = X.indexOf(r.charAt(c++)), 
  t = t << 2 | e >> 4, e = (15 & e) << 4 | a >> 2, o = (3 & a) << 6 | h, n += String.fromCharCode(t), 
  64 != a && (n += String.fromCharCode(e)), 64 != h && (n += String.fromCharCode(o));
  return utf(n);
}