Semantic segmentation of the AHN dataset with the Random Forest Classifier

Three-dimensional (3D) city models are of great significance and are high in demand. They can be used for various useful applications such as urban planning, visibility analysis and estimating the solar irradiation and energy demand of buildings throughout the day. Nowadays, Light Detection And Ranging (LiDAR) sensors are one of the most...

Simplification of Massive TINs with the Streaming Geometries Paradigm

The volume and density of geospatial data is constantly increasing as newer acquisition techniques are developed to create higher-resolution datasets and more countries are creating country-wide datasets such as point clouds. However, methods to deal with this increase in the amount of data are lagging behind and the developments in computer...

Constructing a digital 3D road network for The Netherlands

This research concerned the design and implementation of a system to perform the 3D conversion of a national road network using airborne Lidar data and land-based road elevation measurements, preserving its topology and quantifying output elevation accuracy. While the system was designed with generality in mind, specific Dutch open data datasets...

Automatic detection of waterbeds in shallow muddy water bodies in the Netherlands using green LiDAR

Bathymetric Airborne LiDAR technology is used to map the depth of water bodies. It uses a green light sensor which is able to penetrate the water surface and reach the bottom part of the interesting water areas. However, water conditions affect the capability of the green laser penetration. Factors such as the water clarity, the water turbidity ...

Semantic segmentation of point clouds with the 3D medial axis transform

A point cloud is a representation of shapes, organized in a 3D irregular structure. Point clouds are increasingly used in different applications, ranging from architectural preservation to computer vision. The 3D medial axis transform is a topology preserving, skeleton representation of shapes. It can be used to decompose an object in meaningful...

Improved AHN3 Gridded DTM/DSM

The outcome of the project has been successful from the interpolation perspective, where the final results have shown major improvements over the original rasters, and a multitude of possible other interpolation methods have shown potential. In the end, the algorithm used to create the gridded DTM was<br/>based on Startin’s Laplace interpolation...

Visibility Analysis in a Point Cloud based on the Medial Axis Transform

This thesis proposes a novel medial axis transform (MAT) based method to achieve visibility analysis in a point cloud. There are several advantages of this MAT based method. This method avoids surface reconstruction from a point cloud. It also works for the situation when there is surface missing in the input point cloud. For different point...

3D breakline extraction from point clouds with the Medial Axis Transform

This project develop a new method to generate breakline from the point cloud directly with the MAT. The breakline is a structured line of the object surface which has high curvature. Meanwhile, the reciprocal of the medial edge ball's radius can represent the point with high curvature, which is the fundamental idea of this project. The key parts...

Digitizing Real-World Scenes from Images

3D computer models are starting to play a more and more important role in our society. Realworldsituations are often too complex to explain in a 2D map and also the interest in virtualreality, serious gaming and other technologies that can be based on 3D computer models, isgrowing.

Automatic identification of water courses from AHN3 in flat and engineered landscapes

The Netherlands is characterised by mostly low lying, flat, and engineered agricultural lands, which are sensitive to flooding. To protect against floods, a correct network characterisation is of the utmost importance. A Dutch water resources management company, the HDSR, wishes to have a highly automated method to characterise the water course...

Creating the medial axis transform for billions of lidar points using a memory efficient method

Using Light Detection And Radar (LiDAR) large parts of the earth's geography can be captured an represented as a 3D pointcloud. The whole elevation dataset of the Netherlands (AHN2) is currently available and captured using this technique, it contains around 640 billion points. These massive dataset in its current form is well suited for...