Estimation of enclosure index in urban areas using airborne LiDAR

Abstract

This paper proposes a methodology to estimate an “enclosure index” in urban areas using airborne LiDAR. The index is defined as a ratio of occluded area to whole of area in azimuth angle-elevation angle space. The index can be applied to assess local landscape, and it is expected to estimate it in a wide area at low cost. The author examined the methodology to estimate it using airborne LiDAR data measured in last-pulse mode. The estimated index map was validated with the ground truth data, and the error was acceptable, approximately 3%. Even though the last-pulse mode data may underestimate actual digital surface model (DSM), it was found that the proposed methodology is effective to estimate the index in a wide area at low cost.