Junction and Corner Detection Through the Extraction and Analysis of Line Segments

An algorithm is presented that analyzes the edge structure in images locally, using a geometric approach. A local edge structure that can be interpreted as a corner or a junction is assumed to be representable by a set of line segments. In a first step a segmentation of the local edge structure into line segments is evaluated. This leads to a graph model of the local edge structure, which can be analyzed further using a combinatorial method. The result is a classification as corner or junction together with the absolute orientation and internal structure, like the opening angle of a corner, or the angles between the legs of a junction. Results on synthetic and real data are given.