title: Saving RGB matrix as text
body: <p>I tried to save an RGB matrix in text format but without success. The resolution of the image is 640 x 480. I'm looking for matrix with 640 columns and 480 rows and for every element the corresponding RGB value. For example:</p>
  
  <pre><code>(230, 200, 20) (130, 11, 13) ... # and the others 658 columns
  (200, 230, 20) (11, 130, 13) ... 
  ... # and the others 478 rows
  </code></pre>