Patent ID: 8897547
Filing Date: 2014-11-25
Classification: G01C,G06T

Abstract:
1. A three-dimensional topographical data precision improving device removing noise that occurs in water regions of three-dimensional topographical data as a result of stereo matching errors upon three-dimensional information calculation in three-dimensional topographical data established from stereoscopic photographs, comprising: a memory device configured to store data and program code; a processor configured to access the memory and cause control of: a determination unit determining whether there are any water regions in the input three-dimensional topographical data; a water region specifying unit specifying the range of any one water region; a feature extraction unit extracting feature values on each point in the three-dimensional topographical data based on altitude distribution pattern in the local region of the each point, and extracting feature values within the specified one water region; a segmentation unit segmenting the points in the three-dimensional topographical data into candidate water regions and non-water regions by using the extracted feature values within the specified water region as a water region determination reference value, comparing the feature values of each point in the three-dimensional topographical data with the water region determination reference value, and determining that the point belongs to the candidate water region if the difference is equal to or smaller than a given threshold, and otherwise determining that the point belongs to the non-water region; a water region extraction unit extracting a connected component having the same or wider area than a given threshold among the candidate water regions as a water region based on the results of the segmentation unit; and a plane creation unit creating a corrected plane joined to the boundary of each water region extracted by the water region extraction unit using the altitudes of the surrounding non-water regions adjoining to the water region extracted by the water region extraction unit, and replacing the water region extracted by the water region extraction unit with the corrected plane.