title: how to convert two bytes into integer
body: <p>I'm trying to size of a BMP file in bytes, but i don't know how to read two (or n) bytes and convert it to int.
  For example: </p>
  
  <pre><code>13 0B 00 00 = 2835 
  46 04 00 00 = 1094
  B6 51 01 00 = 86454
  </code></pre>