Line detection in a figure (point cloud)

Hello, I have a figure (point cloud) as you can see in the picture.

Now I want to detect if there are two lines with an fix distance.

Can someone help me please how to do it?

Answer 1

[Image Analyst]

Looks like you might have to use RANSAC to find the lines. Once you've found a line, remove those points to find the next line(s).

http://en.wikipedia.org/wiki/RANSAC

[Dennis Sattelmaier]

Thank you for the fast answer. But how I have to write the code for RANSAC? There is no Matlab describtion for RANSAC.

[Image Analyst]

There are some in the File Exchange: http://www.mathworks.com/matlabcentral/fileexchange/?utf8=%E2%9C%93&term=ransac