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Understanding the LiDAR Images.
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The making of the Samoa LiDAR Images:
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The LiDAR used on this web page was originally acquired during the Airborne Lidar Bathymetric Topographic Survey of Samoa 2015 [41Mb]. CSS acquire their copies of the classified LAS files from MNRE between February 2017 and June 2017. The process of rendering the LAS files into viewable LiDAR images started in February 2017 and was finally completed in December 2017.
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The basic steps used in converting the classified LAS files into viewable LiDAR images were:
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1.
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Acquire LiDAR LAS files (raw classified LiDAR point cloud data).
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2.
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Convert LAS into DEM (Digital Elevation Model) using QGIS with “LAStools:las2dem”.
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3.
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Render DEMs into Sky-view Factor geotifs (georeferenced pictures) with “Relief Visualization Toolbox”.
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4.
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Input TIFs (Tagged Image File Format pictures) into QGIS.
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What do the LiDAR images show us about Samoa?
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The Lidar data for Samoa that has been analyzed shows us that the islands of Samoa are literally covered with archaeological remains (features) from the coast to as far inland as can be seen where the deep forest canopy has been cleared (8 km. or more inland in some areas).
The features visible include platforms (for houses) [tulagafale], star mounds [fetu ma'a or tia se lupe], terraces [mafola], walls [pa ma’a], walled walkways [auala savali], elevated walkways [auala savali], large earth ovens (umu ele'ele or umu ti ), drainage channels [omo], large pits (lua'i masi), forts (olo), and just piles of stone [mauga ma’a].
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