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Modern Geomatics Technologies and Applications
Figure 10. Sectioning of point clouds. (a) is a sample section
After dividing the point clouds data to equal and smaller sections, noisy points were eliminated. For eliminating noisy
points, 20 neighborhood points and a coefficient equal 1 were considered. Noisy data and denoised data are illustrated in Figure
11-a and Figure 11-b respectively.
(a) (b)
Figure 11. Noise removal of the point clouds with abnormal altitude. (a) A sample section which included noisy
points; (b) Removing the noisy points from selected section
In the ground removing filtering, cell size was considered regard to minimum size of building and 5 m threshold was
used. Figure 12-b illustrates the remaining points from a sample section after removing ground points and low-height objects.
(a) (b)
Figure 12. Ground removing step. (a) A sample of section; (b) Removing ground points
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