title: Inverse of rgb2ycbcr() in Octave? (No ycbcr2rgb)
body: <p>How do I convert the output of <code>rgb2ycbcr</code> back to RGB in Octave?<br>
  I can't find a <code>ycbcr2rgb</code> function in the <code>image</code> package.</p>