Displaying a Contour Plot of Image Data :: Analyzing and Enhancing Images (Image Processing Toolbox User's Guide)

Image Processing Toolbox User's Guide

Displaying a Contour Plot of Image Data

You can use the toolbox function imcontour to display a contour plot of the data in a grayscale image. A contour is a path in an image along which the image intensity values are equal to a constant. This function is similar to the contour function in MATLAB, but it automatically sets up the axes so their orientation and aspect ratio match the image.

This example displays a grayscale image of grains of rice and a contour plot of the image data:

Read a grayscale image and display it.

```
I = imread('rice.png');
imshow(I)
```

Display a contour plot of the grayscale image.

```
figure, imcontour(I,3)
```

You can use the clabel function to label the levels of the contours. See the description of clabel in the MATLAB Function Reference for details.

Getting the Intensity Profile of an Image Creating an Image Histogram