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<h2 class="chapter">31 Image Processing</h2>
<p>Since an image basically is a matrix Octave is a very powerful
environment for processing and analyzing images. To illustrate
how easy it is to do image processing in Octave, the following
example will load an image, smooth it by a 5-by-5 averaging filter,
and compute the gradient of the smoothed image.
<pre class="example"> I = imread ("myimage.jpg");
S = conv2 (I, ones (5, 5) / 25, "same");
[Dx, Dy] = gradient (S);
</pre>
<p class="noindent">In this example <code>S</code> contains the smoothed image, and <code>Dx</code>
and <code>Dy</code> contains the partial spatial derivatives of the image.
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