## 32 Image Processing

Since an image basically is a matrix Octave is a very powerful environment for processing and analysing 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.

         I = loadimage ("default.img");
         S = conv2 (I, ones (5, 5) / 25, "same");
         [Dx, Dy] = gradient (S);

In this example `S` contains the smoothed image, and `Dx` and `Dy` contains the partial spatial derivatives of the image.