System to find edge correspondences in unstructured stereo images
Rachid Gherbi, Alexandre Parodi · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 1992
We present a new edge-based matching algorithm that can be applied for unstructured stereo images. We first review briefly a major recent development in establishing stereo correspondences and show that a great deal of research in stereo is needed in order to apply stereo techniques to solve more real-world problems. We then discuss why we use edges (without simplification and without linking) as primitives to be matched rather than other primitives (points, regions, ...) and what adequate edge detector should be used. We then argue that matching a whole parts of edges should be done rather than comparison of straight line segments. We then discuss the occlusion problem and some defects of the edge detector that possibly cut the edges to several pieces, and argue that partial matching of edges can be a solution to such problems. We then explain what best matching criteria are used, comprising both shape and gray level attributes. These criteria are chosen for their pertinence, representation and computation simplicity and for their similarity to those probably used in human vision system. Finally, complete quantitative experimental results are shown with various indoor and outdoor real world scenes.