Accurate range data acquisition in the light striping ranging system needs correct peak position of the laser striped image in subpixel level. In this thesis, a graylevel thinning algorithm in the laser ranging system which is used to extract peak pixels composed by eight neighborhood is proposed and the position of peak line (thinned image) is compensated in subpixel level by locally straight line (LSL) which is an approximation of ideal line. In graylevel thinning, local projection is used to find the local slope of peak line. When saturation occurred the correct peak pixel is determined by local profiling of the perpendicular direction of local slope. Each line segment is labeled to proper types of LSL by neighborhood line segment. The subpixel position is compensated by the LSL of 18 types. Acquired range data are transformed to range images for flexible usage.
