<html lang="en"> <head> <title>Image Processing - GNU Octave</title> <meta http-equiv="Content-Type" content="text/html"> <meta name="description" content="GNU Octave"> <meta name="generator" content="makeinfo 4.13"> <link title="Top" rel="start" href="index.html#Top"> <link rel="prev" href="Signal-Processing.html#Signal-Processing" title="Signal Processing"> <link rel="next" href="Audio-Processing.html#Audio-Processing" title="Audio Processing"> <link href="http://www.gnu.org/software/texinfo/" rel="generator-home" title="Texinfo Homepage"> <meta http-equiv="Content-Style-Type" content="text/css"> <style type="text/css"><!-- pre.display { font-family:inherit } pre.format { font-family:inherit } pre.smalldisplay { font-family:inherit; font-size:smaller } pre.smallformat { font-family:inherit; font-size:smaller } pre.smallexample { font-size:smaller } pre.smalllisp { font-size:smaller } span.sc { font-variant:small-caps } span.roman { font-family:serif; font-weight:normal; } span.sansserif { font-family:sans-serif; font-weight:normal; } --></style> </head> <body> <div class="node"> <a name="Image-Processing"></a> <p> Next: <a rel="next" accesskey="n" href="Audio-Processing.html#Audio-Processing">Audio Processing</a>, Previous: <a rel="previous" accesskey="p" href="Signal-Processing.html#Signal-Processing">Signal Processing</a>, Up: <a rel="up" accesskey="u" href="index.html#Top">Top</a> <hr> </div> <h2 class="chapter">32 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. <ul class="menu"> <li><a accesskey="1" href="Loading-and-Saving-Images.html#Loading-and-Saving-Images">Loading and Saving Images</a> <li><a accesskey="2" href="Displaying-Images.html#Displaying-Images">Displaying Images</a> <li><a accesskey="3" href="Representing-Images.html#Representing-Images">Representing Images</a> <li><a accesskey="4" href="Plotting-on-top-of-Images.html#Plotting-on-top-of-Images">Plotting on top of Images</a> <li><a accesskey="5" href="Color-Conversion.html#Color-Conversion">Color Conversion</a> </ul> </body></html>