GEOMETRIC CORRECTION OF TOPOGRAPHIC MAPS SCANNED BY AN IMAGE SCANNER

Contour Line Recognition From Scanned Topographic Maps

Automatic Contour Labeling for Scanned Topographic Maps

In many mapping organizations, existing topographic paper maps comprise the most complete source of elevation. data; the objective of this research is to capture the elevation data (which is in contour form) in a GIS. The topographic relief plate which shows no height information can be scanned into a GIS. The remaining task is then to label these isolines. This paper discusses a methodology fo...

Vectorization of Linear Features in Scanned Topographic Maps Using Adaptive Image Segmentation and Sequential Line Tracking

Vectorization of cartographic features is a difficult task in geographic information acquisition from topographic maps. This paper presents a semi-automatic approach to linear feature vectorization directly in original scanned colour topographic maps without layer separation. In the approach, a sliding window is added on a user-given linear feature, and the current line in the window is segment...

An Implementation of Automatic Contour Line Extraction from Scanned Digital Topographic Maps

This paper proposes a method of implementation of automatic contour line extraction from scanned digital topographic maps. First, color image segmentation is executed to recognize the features on digital topographic maps, second, morphological and filtering operations are presented to eliminate all unwanted information from digital topographic map except from contour lines. Then, resolving the ...

Topographic and Distance Effects in Laser Scanner Intensity Correction

The effect of incidence angle on the intensity of laser backscatter has been studied in photonics and optics, but the applications of these results to remote sensing of natural land targets are limited, as well as the availability of experimental validation data for airborne and terrestrial laser scanning, where the incidence angle correction using the Lambertian scattering law is common. We ha...