python.workflows.qltAccuracyRegion Namespace Reference

Performs an absolute accuracy check for entire flight blocks w.r.t. to reference regions (on the ground). More...

Classes
class	qltAccuracyRegion

Variables
	script

Detailed Description

Performs an absolute accuracy check for entire flight blocks w.r.t. to reference regions (on the ground).

This script is intended to check the absolute accuracy of (laser scanning) point clouds (PCs). For this purpose the absolute accuracy is reported as 3D shifts between the laser points (check PC) and given reference data (reference PC). Since there are no corresponding points between both PCs, these accuracy measures can only be derived for larger groups of points – termed regions. For each region a transformation of the check PC towards the reference PC is computed using opalsICP. The effect of this transformation on the center of gravity of the check PC within each region is then reported as absolute accuracy measure. This is a 3D displacement vector for each region. For this ICP based approach it is required that within each region at least three smooth tilted surfaces (e.g. roofs) with different expositions are present. The resulting accuracy information is stored in a shape file and a text file. The input file for the reference PC defines the boundary of the individual polygons of each region. Before ICP is computed, these polygons from the reference PC are densified with 3D points (using opalsRasterize) where the density is derived from the check PC.

See also

Script documentation