Low-level Grouping of Straight Line Segments

In this paper we present a formalism for the formation of self consistent, hierarchical, "Low-Level" groupings of pairs of straight line segments from which all higher level groupings may be derived. Additionally, each low-level grouping is associated with a "Quality" factor, based on evidential reasoning, which reflects how much the groupings differ from mathematically perfect ones. This formalism has been incorporated into algorithms within the "LPEG" software package produced at the University of Surrey. LPEG was developed as part of the Vision As Process [Crowley et al., 1989] project. We present results of the application of these algorithms to sets of line segments extracted from a test image.