Abstract
Spatiotemporal urban data analysis is one of the most relevant and challenging topics in the computer graphics and information visualization research areas. This master project introduces a novel solution, named Temporal Topology Density Map (TTDM), to represent 2D discrete spatial data with temporal variations into a 2D continuous spatial space constrained by a topology. Two algorithms are introduced in the conducted research. The first one integrates Image-Foresting Transform (IFT) into the computation of Topology Density Map (TDM), which leads to an efficient solution. The second one, in turn, combines topological density maps with Change Frequency Heatmap (CFH) to convey visual information on changes over time, which lead to a new visualization method. Two case studies related to the analysis of response time associated with emergency services and walkability changes over time for areas of interest demonstrate the effectiveness of the proposed approach in challenging scenarios. We could observe that the proposed solution provides an intuitive visualization for supporting the accurate analysis of spatiotemporal data changes over time using topology density maps.