Hough Transformation in Slope-Intercept Form


This applet demonstrates the Hough transformation for lines. It detects lines in the image space by finding clusters in the Hough space.

Theoretical background

How to use the applet

Below you can see two images, the first image on the left side is the input image in which the lines will be searched. The second image shows the Hough space.When you move the mouse pointer over the input image a cyan colored line appears on the Hough image. It represents the transformation line of the active mouse position, which will be added into the Hough space if you draw a dot by pressing the left mouse button. You can also drag the mouse button to transform multiple points. While moving the mouse over the Hough space a red line appears on the input image, which correspond to the back transformation of the Hough point. There are two possible operators to work with. The first one is the simple point tool for drawing points and a line operator to draw line. Both tools can be chosen by pressing the   -button. If you want to find automatically some maxima/cluster in the Hough space, just press the -button. After that you have to choose the number of clusters which should be found. Afterwards the clusters are visualized as yellow lines in the image space and the positions of the maxima are marked by green rectangles in Hough space. In this way you can realize how the Hough transformation works. For a better illustration of the point coordinates, you can activate coordinate systems in both images by pressing the -button. The last feature is the -button which resets both images.





Authors: René Iser, Behrang Karimibabak and Simon Winkelbach

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