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<h2 class="chapter" id="Image-Processing-1"><span>32 Image Processing<a class="copiable-link" href="#Image-Processing-1"> ¶</a></span></h2>
<p>Since an image is basically 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.
</p>
<div class="example">
<div class="group"><pre class="example-preformatted">I = imread ("myimage.jpg");
S = conv2 (I, ones (5, 5) / 25, "same");
[Dx, Dy] = gradient (S);
</pre></div></div>
<p>In this example <code class="code">S</code> contains the smoothed image, and <code class="code">Dx</code>
and <code class="code">Dy</code> contains the partial spatial derivatives of the image.
</p>
<ul class="mini-toc">
<li><a href="Loading-and-Saving-Images.html" accesskey="1">Loading and Saving Images</a></li>
<li><a href="Displaying-Images.html" accesskey="2">Displaying Images</a></li>
<li><a href="Representing-Images.html" accesskey="3">Representing Images</a></li>
<li><a href="Plotting-on-top-of-Images.html" accesskey="4">Plotting on top of Images</a></li>
<li><a href="Color-Conversion.html" accesskey="5">Color Conversion</a></li>
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