A Comparative Study of Curvature-Based and Differential Versions of Dotter Raster-stereography Techniques

Abstract

Conventional Line-based Raster-stereography has been a popular technique for 3-D surface topography. However, in its application for human face screening, the problem of line breaking was observed. In order to resolve this problem, there came up a new technique called dotted raster-stereography. The previously reported version of dotted raster-stereography extracted the curvature features of human face. This paper presents a modified version, viz. differential dotted raster-stereography in which instead of curvature, differences in straight line distances between adjacent points are calculated. A comparative picture of the two versions of dotted raster-stereography techniques is presented. Results suggest that this new differential version of dotted raster-stereography algorithm is faster in execution due to its simpler implementation in software, though lower in accuracy, as compared with the previously reported curvature-based version of dotted raster stereography.