Contour Line Generation from Lidar Point clouds

Tool Created with/for OpenTopography.org

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This tool allows environmental researchers, architects, urban planners, ecological planners, and many more of the users of OpenTopography.org to generate contour line shapefiles from Lidar point cloud data, as opposed to the traditional method of surveying. With the advancement and accessibility of Lidar data, this technological advance in contour line generation can now be completed on most areas within North America. 

This tool was created with and for OpenTopography.org, allowing users to download contour line shapefiles derived directly from the Lidar point cloud database. The python script uses the TIN interpolation algorithm to generate the DEM, preforms a Gaussian filter on the DEM, and finally outputs the contour lines using GDAL.

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DEM generation (TIN)
 
TIN (Triangulated Irregular Network) interpolation algorithm used to generate raster digital elevation models from point cloud dataset
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Gaussian Filter
 
Within the Gaussian smoothing module, sigma and radius controls the variation around the mean and the number of cells that are mathematically represented
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GDAL contour line generation
 
Line intervals are input by user, going as low as 0.1 meter
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The user interface give users additional options  regarding the Gaussian smoothing variables, as well as contour interval and file output type. This tool can be accessed at www.OpenTopography.org