Annotating 3D Content in Interactive, Virtual Worlds Christine - PowerPoint PPT Presentation

Annotating 3D Content in Interactive, Virtual Worlds Christine LEHMANN Jürgen DÖLLNER

Agenda 2 1. Motivation 2. Image-based Labeing of 3D Content 3. Enhanced Visibility Analysis 4. Smooth Transitions 5. Conclusions Annotating 3D Content in Interactive, Virtual Worlds | Web3D 2013 | Christine LEHMANN

Foundations: What is Labeling? Labeling algorithms are faced with a number of fundamental challenges including: 3 □ Find non-conflicting positions close to labeled objects in the view plane (label embedding) □ Guarantee non-ambiguous assignments □ Ensure readability of labels Example: Boundary Labeling (external) [Bekos et al.: „ Boundary Labeling with Octilinear Different Approaches for labeling Leaders “, 2008] with different advantages : □ Internal labels provide fast assocating to labeled objects □ External labels can be applied to very small objects (small visible amount) Example: Street Labeling (internal) Annotating 3D Content in Interactive, Virtual Worlds | Web3D 2013 | Christine LEHMANN

Example: Google Maps 4 Annotating 3D Content in Interactive, Virtual Worlds | Web3D 2013 | Christine LEHMANN

Example: Google Earth (1/3) 5 Annotating 3D Content in Interactive, Virtual Worlds | Web3D 2013 | Christine LEHMANN

Example: Google Earth (2/3) 6 ? Annotating 3D Content in Interactive, Virtual Worlds | Web3D 2013 | Christine LEHMANN

Example: Google Earth (3/3) 7 ? Annotating 3D Content in Interactive, Virtual Worlds | Web3D 2013 | Christine LEHMANN

Contribution ■ Our method enables attaching labels to 8 salient points and lines for internal label placement ■ It uses visibility analysis to overcome general labeling obstacles, most important unambiguous label assignment Use both internal and external labeling: ■ Apply internal and external labels depending on visibility analysis ■ Enable transitions between external and internal label placement Annotating 3D Content in Interactive, Virtual Worlds | Web3D 2013 | Christine LEHMANN

Example: Internal and External labels combined 9 Annotating 3D Content in Interactive, Virtual Worlds | Web3D 2013 | Christine LEHMANN

Image-based Labling of 3D Content ■ Labels are placed exclusively on 10 visible areas of labeled objects ■ Visible pixels of 3D objects are collected from the identity-map (id-map) Example: Internal Label Placement and External Label Placement with according id-maps. Annotating 3D Content in Interactive, Virtual Worlds | Web3D 2013 | Christine LEHMANN

Enhanced Visibility Analysis for Labeling ■ From visible pixels, compute the distance transform and the normal field 11 Annotating 3D Content in Interactive, Virtual Worlds | Web3D 2013 | Christine LEHMANN

Enhanced Visibility Analysis for Labeling 12 Annotating 3D Content in Interactive, Virtual Worlds | Web3D 2013 | Christine LEHMANN

Enhanced Visibility Analysis for Labeling 13 Annotating 3D Content in Interactive, Virtual Worlds | Web3D 2013 | Christine LEHMANN

Enhanced Visibility Analysis for Labeling 14 Annotating 3D Content in Interactive, Virtual Worlds | Web3D 2013 | Christine LEHMANN

Enhanced Visibility Analysis for Labeling 15 Annotating 3D Content in Interactive, Virtual Worlds | Web3D 2013 | Christine LEHMANN

Smooth Transitions Labels switch from internal (with horizontal orientation) to external by 16 ”walking” along the arrows (normal field) . Annotating 3D Content in Interactive, Virtual Worlds | Web3D 2013 | Christine LEHMANN

Conclusions 17 Image-based label placement: ■ Suitable for responsive systems and interactive 2D/2.5D/3D systems ■ Easy integration into service-based systems Enhanced Visibility-driven label placement: ■ Unambiguous label assignments ■ No time-consuming 3D geometry analysis of labeled objects ■ Dynamic switching between internal and external labeling ■ Simultaneous usage of external and internal labeling based on visibility analysis Annotating 3D Content in Interactive, Virtual Worlds | Web3D 2013 | Christine LEHMANN

Conclusions Contact: 18 www.4dndvis.de  Christine Lehmann christine.lehmann@hpi.uni-potsdam.de  Jürgen Döllner juergen.doellner@hpi.uni-potsdam.de Publications: http://www.hpi.uni-potsdam.de/doellner/4dndvis/publikationen.html This work was funded by the Federal Ministry of Education and Research (BMBF), Germany within the InnoProfile Transfer research group "4DnD-Vis". Annotating 3D Content in Interactive, Virtual Worlds | Web3D 2013 | Christine LEHMANN