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Next: <a href="Audio-Processing.html#Audio-Processing" accesskey="n" rel="next">Audio Processing</a>, Previous: <a href="Signal-Processing.html#Signal-Processing" accesskey="p" rel="prev">Signal Processing</a>, Up: <a href="index.html#Top" accesskey="u" rel="up">Top</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Concept-Index.html#Concept-Index" title="Index" rel="index">Index</a>]</p>
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<a name="Image-Processing-1"></a>
<h2 class="chapter">32 Image Processing</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">
<pre class="example">I = imread ("myimage.jpg");
S = conv2 (I, ones (5, 5) / 25, "same");
[Dx, Dy] = gradient (S);
</pre></div>
<p>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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