RANSAC Lines

To solve last week's problem of fitting partial lines, Serge suggested RANSAC. I implemented RANSAC for line fitting and the results are good as expected. RANSAC basically takes n random points, creates a model based on these points, calculate the error for all the data points from this model and add to a list of possible models if within a threshold count.More details can be found at wikipedia

Here is a line fitting to the motorcycle frame from last week:


This is one from a car in the background:


As seen in the first image, we now have a more robust model for detecting motion towards a traffic stop.