초   록

 This paper presents a safe path estimation method for visual-impaired people in an outdoor sidewalk
environment. Unlike many existing methods that rely on stereo-vision, the proposed method aims to detect generic
obstacles in a cluttered road environment by using just single camera mounted at user’s belly. One of the main difficulties of using single camera in outdoor navigation task is the discrimination of obstacles with cluttered background. To solve this problem, this paper makes use of the inhomogeneous re-sampling property of top-view transform. By mapping the original image to a top-view virtual plane using top-view transform, background edges in the near-field are sub-sampled while obstacle edges in the far-field are oversampled. Morphology filters with connected component analysis are used to enhance obstacle edges as edge-blobs with larger size, whereas sparse edges from background are filtered out. Based  on the identified obstacles, safe path is estimated by tracking a
polar edge-blob histogram on the top-view domain. The algorithm is tested in different sidewalk scenes with complex pavements, and its efficiency has been confirmed.