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Edgel Class Reference
[Edge Detection]

#include <vigra/edgedetection.hxx>

List of all members.

Public Attributes

float orientation
float strength
float x
float y

Detailed Description

Helper class that stores edgel attributes.


Member Data Documentation

float x

The edgel's sub-pixel x coordinate.

float y

The edgel's sub-pixel y coordinate.

float strength

The edgel's strength (magnitude of the gradient vector).

float orientation

The edgel's orientation. This is the angle between the x-axis and the edge, so that the bright side of the edge is on the right. The angle is measured counter-clockwise in radians like this:

  edgel axis
      \  (bright side)
 (dark \
 side)  \ /__
         \\  \ orientation angle
          \  |
           +------------> x-axis
           |
           |
           |
           |
    y-axis V

So, for example a vertical edge with its dark side on the left has orientation PI/2, and a horizontal edge with dark side on top has orientation 0. Obviously, the edge's orientation changes by PI if the contrast is reversed.


The documentation for this class was generated from the following file:

© Ullrich Köthe (ullrich.koethe@iwr.uni-heidelberg.de)
Heidelberg Collaboratory for Image Processing, University of Heidelberg, Germany

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VIGRA 1.6.0 (5 Nov 2009)