An approach to extract straight lines with subpixel accuracy

Abstract

This paper presents a novel approach to extract the straight line with subpixel accuracy in images. Firstly, we model the line profiles and analyze their behavior in linear scale-space. From this analysis, algorithms to extract line points with sub-pixel resolution are derived. After that, a modified progressive probabilistic Hough transform (PPHT) algorithm, which is capable of obtaining subpixel accuracy line position, is proposed to find straight line structures from the line points. Finally, the performance of the approach is demonstrated using synthetic and real images. The experimental results show that the approach is able to extract straight lines effectively and can achieve subpixel accuracy. © 2012 Springer-Verlag.