This paper presents a very efficient method for vectorizing and labeling very large raster hypsographic map images. By extending the contour tree (Freeman and Morse, 1967) to a contour graph, open contour lines and carrying contour lines can be handled. The ambiguities of the topological relationships among contour lines are resolved using map structure information, i.e., elevation tags and ind...

This paper addresses the problem of contour line extraction from scanned topographic maps in poor condition. A novel method is developed, using knowledge of cartography and graphics to extract contours by removing other layers which overlay the contours, and reconstructing the contour lines. The contributions of this paper are the supplementation of the use of knowledge discovery for extraction...

Numerical comparison of crystallographic contour maps is used extensively in structure solution and model refinement, analysis and validation. However, traditional metrics such as the map correlation coefficient (map CC, real-space CC or RSCC) sometimes contradict the results of visual assessment of the corresponding maps. This article explains such apparent contradictions and suggests new metr...

in this paper, we used a shape matching algorithm to recognize farsi digits. for each sampled point on the contour of a shape, we obtain a descriptor showing the distribution of the other points of the contour, with respect to this point. based on these descriptors, we find the corresponding points of the two contours and take the sum of their distances as a dissimilarity measure between two sh...

We propose a biologically motivated computational step, called non-classical receptive field (non-CRF) inhibition, to improve contour detection in images of natural scenes. We augment a Gabor energy operator with non-CRF inhibition. The resulting contour operator responds strongly to isolated lines, edges, and contours but exhibits a weaker or no response to edges that make part of texture. As ...

Evaluating the power densities emitted by GSM1800 and GSM900 BTS antennas isconducted via two methods. Measurements are carried out in half a square meter grids around twoantennas. CST Microwave STUDIO software is employed to estimate the power densities in order fordetailed antenna and tower modeling and simulation of power density. Finally, measurements obtainedfrom computational and experime...

Topographic maps represent the delineation of features of interest in a terrain by means of contour lines. There are several benefits of maintaining topographic maps in sensor networks they can be used for resolving spatial queries, visualizing available resources in the network, and understanding spatio-temporal characteristics about the events being monitored. In this paper, we consider the p...

Map digitization is still an ongoing research in development of GIS, photogrammetry, remote sensing, military, urban planning and etc. Majority of recent approach, either associates with human interaction or semi-automated process are insufficient in various aspects. There are usually time-consuming, inefficient, and shown inaccuracies in digitized data. This research is intended to develop an ...

The spatial relationships of contours play important roles in many areas such as extracting topographic features from contour maps, automatically identifying elevations of scanned contours, et al.. In those areas, one key issue is making computers identify the relationships of contours. The spatial relationships of contours are usually represented by contour tree. Contour tree is essentially a ...