Algorithm 2 RoadWidth_Determination() algorithm.

Require Segmented image, existing road centre-line

Ensure Width of the road corresponding to the extracted segment

1:

Find the common region between the road centre-line and segmented region

2:

Perform the thinning process in extracted segment to find end points

3:

if Segment contains only two end points then

4:

 Find the angle between the two end points of the extracted segment with reference to X-axis

5:

else if Segment contains more than two end points then

6:

 Find the median angle between all the possible combination of the end points

7:

 Find the average angle between the median angle of the current segment and angle of previously traversed segment

8:

Grow the obtained common region in the direction of the angle detected until the area of the region is equal to the area of the extracted segment, and provided it meets the width ratio

9:

Grown region provides the road-width for the corresponding segment