Edge Detection

Edges are very important to any vision system (biological or machine).

• They are fairly cheap to compute
  
• They do provide strong visual clues that can help the recognition process.
  
• Edges are affected by noise present in an image though.

An edge may be regarded as a boundary between two dissimilar regions in an image.

These may be different surfaces of the object, or perhaps a boundary between light and shadow falling on a single surface.

In principle an edge is easy to find since differences in pixel values between regions are relatively easy to calculate by considering gradients.

 

• Representing Lines
  
• Extracting Edges from Images
  
• Detecting Edge Points
  
  
  • Gradient based methods
    
  • Second Order Methods