Computer Vision Demonstration Website

Electronics and Computer Science
University of Southampton

Hough Transform

The Hough Transform is a method for finding shapes in an image. The Line Hough has been implemented here, which is used to find lines within an image. The Hough Transform can also be used to find circles, or even generalised to find any shapes. The applet below allows the number of output lines to be selected. The "Acc" option shows the output of the accumulator (polar space output image).

How it works

The line Hough Transform generates a curve in polar space for each edge point in Cartesian space. This polar HT accumulator array contains votes for each parameter pair. The peaks in this image are then inverse transformed to give a set of lines that represent these edges.

Code

Image processing classes:

• lineHough.java
• sobel.java
• hystThresh.java

Demo framework:

• houghDemo.java

The pages were designed and developed for educational purposes only, to demonstrate how computer vision techniques work. They are designed for no other purpose and neither the authors nor their institutions accept any liability concerning use of these pages.

Links

Mark Nixon & Alberto Aguado, 2002, Feature Extraction & Image Processing, Newnes

ECS | Feature Extraction & Image Processing | © 2005 University of Southampton