In this study, we present the two dimensional object silhouette by a one dimensional descriptor, which,preserves the perceptual structure of its shape. The proposed descriptor is based on the moments of the angles between the bearings of a point on the boundary, in a set of neighborhood systems. At each point on the boundary, the angle between a pair of bearings is calculated to extract the topological information of the boundary in a given locality. The proposed method does not use any-heuristic rule or empirical threshold value in the shape representation. The similarity between the patterns is measured by elastic matching of the descriptors. The proposed shape descriptor is tested on dataset of MPEG 7 Core Experiments Shape-1. The experiments show better results than the previous studies reported in the literature.