title: Convert hex to ascii characters
body: <p>Is it possible to represent a sequence of hex characters (0-9A-F) with a sequence of 0-9a-zA-Z characters, so the the result sequence is smaller and can be decoded?</p>
  
  <p>For example:</p>
  
  <pre><code>$hex = '5d41402abc4b2a76b9719d911017c592';
  echo $string = encode($hex); // someASCIIletters123
  echo decode(string) == $hex; //true
  </code></pre>