GIS Lidar Work, Djurgården, Stockholm 2023-04-14
In this task, the aim was to gather lidar point cloud and urban building data, and along with topographic models and tools, calculate heights of objects/buildings, create and compare viewsheds from different locations in space, and create 3D-scenes of the analysed data.
Slope was tested on both DEM and DSM were DEM was chosen as the more fit alternative. Above is a slope analysis (30% transparency) made from the DSM in the trial phase.
Visualization of the point cloud data (left) and a 3D scene (right). The highest point was missing in the raw data and was added manually in the attribute table.
Final map made of a topography > slope analysis on DEM (30% transparency), with the viewshed analysis on top. Pink area equal visible area viewed from the highest point & turquoise area equal visible area from ground on the same location.
Primary Tools Used in the Work Process
• data & metadata collection (LM, geolex etc.)
• data conversion LAZ/LASD/raster/vector & float/integers etc
• mosaic
• slope
• geodesic viewsheds
• raster calculator & calculate building heights
• zonal statistics & spatial joins
• attribute table manual edit
• 3D scenes DEM/DSM, ground, slope, building extrusion, viewsheds
• symbology & design
• data conversion LAZ/LASD/raster/vector & float/integers etc
• mosaic
• slope
• geodesic viewsheds
• raster calculator & calculate building heights
• zonal statistics & spatial joins
• attribute table manual edit
• 3D scenes DEM/DSM, ground, slope, building extrusion, viewsheds
• symbology & design
The work presented as a poster.
Data Sources: Property Map & Laser Data 2019 © Lantmäteriet.
