Hough Transform

A good description is on this page.

Wikipedia also has its own Hough Transform article.

Pros

• Able to detect dashed lines

Cons

• Can only detect straight lines, making it almost useless for curved lines - which will probably be common
  • Useless for detecting curved lines
• Designed to detect lines as opposed to detecting line segments
• Computationally expensive (when compared to simple filters)

Input

• A binary/grayscale image hilighting the line-pixels in the input image

Output

• A list of the positions/orientations of the lines detected in the input image

Pictures

Two solid straight lines

One solid curvy line

Two solid curvy lines

Two dashed curvy lines

No lines at all! Just some salt noise.

Yikes!

Double yikes! The robot would probably panic upon seeing this. :P