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Interactive Density Maps for Moving Objects
January/February 2012 (vol. 32 no. 1)
pp. 56-66
R. Scheepens, Eindhoven Univ. of Technol., Eindhoven, Netherlands
N. Willems, Eindhoven Univ. of Technol., Eindhoven, Netherlands
H. van de Wetering, Eindhoven Univ. of Technol., Eindhoven, Netherlands
J. van Wijk, Eindhoven Univ. of Technol., Eindhoven, Netherlands
Trajectories capture the movements of objects with multiple attributes. A visualization method called density maps shows trends in these trajectories. Density map creation involves aggregating smoothed trajectories in a density field and then visualizing the field. Users can explore attributes along trajectories by calculating a density field for multiple data subsets. The method then either combines these density fields into a new density field or visualizes them and then combines them. Using an interactive distribution map, users can define subsets and, supported by graphics hardware, get fast feedback for these computationally expensive density field calculations. Given the generic method and the lack of domain-specific assumptions, this method might also be applicable for trajectories in other domains.

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2. N. Willems, H. van de Wetering, and J. J. van Wijk, "Visualization of Vessel Movements," Computer Graphics Forum, vol. 28, no. 3, 2009, pp. 959–966.

Index Terms:
Trajectory,Image color analysis,Density measurement,Data visualization,Rendering (computer graphics),Smoothing methods,Object recognition,computer graphics,trajectories,multivariate data,smoothing,kernel density estimation
Citation:
R. Scheepens, N. Willems, H. van de Wetering, J. van Wijk, "Interactive Density Maps for Moving Objects," IEEE Computer Graphics and Applications, vol. 32, no. 1, pp. 56-66, Jan.-Feb. 2012, doi:10.1109/MCG.2011.88
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