1. A Unified Multi-Surface, Multi- Resolution Workspace with Camera-Based Scanning and Projector- Based Illumination Tyler Johnson and Henry Fuchs University of North Carolina – Chapel Hill IPT/EGVE July 18, 2007 - Weimar, Germany

2. 2 T. Johnson, H. Fuchs, “ A Unified Multi-Surface, Multi-Resolution Workspace” Multi-Projector Display

3. 3 T. Johnson, H. Fuchs, “ A Unified Multi-Surface, Multi-Resolution Workspace” Previous Work Projected desktop Interaction with virtual documents Camera-based scanning Digital Desk [Wellner ’93] Multi-resolution workspacesFocus Plus Context Displays [Baudisch ’01], Escritoire [Ashdown ’03] Multi-surface projected workspace[Ashdown ’04]

4. 4 T. Johnson, H. Fuchs, “ A Unified Multi-Surface, Multi-Resolution Workspace” Workspace Configuration

5. 5 T. Johnson, H. Fuchs, “ A Unified Multi-Surface, Multi-Resolution Workspace” Calibration Cameras pre-calibrated Project structured light to determine Projector calibration Workspace geometry RANSAC-based plane-fitting. [Quirk EDT ’06] Also, display structure light with LCD Calibrate as a projector Workspace Walls LCD Panel Encoded Structured Light

6. 6 T. Johnson, H. Fuchs, “ A Unified Multi-Surface, Multi-Resolution Workspace” Two-Pass Rendering Display Surface Projector Viewer Determine image warping to remove distortion caused by surface geometry

7. 7 T. Johnson, H. Fuchs, “ A Unified Multi-Surface, Multi-Resolution Workspace” Single vs Multi-Surface Content Two methods of display Single vs. multi-surface

8. 8 T. Johnson, H. Fuchs, “ A Unified Multi-Surface, Multi-Resolution Workspace” Single Surface Content User selects region where the window should appear Compute P-Matrix from 3D->2D corner correspondences Choose arbitrary COP Two-pass rendering determines what to project

9. 9 T. Johnson, H. Fuchs, “ A Unified Multi-Surface, Multi-Resolution Workspace” Multi-Surface Content Same as for single surface, except that COP is user viewpoint Viewpoint can be obtained from separate tracking system

10. 10 T. Johnson, H. Fuchs, “ A Unified Multi-Surface, Multi-Resolution Workspace” Projector-Based Illumination Projection of imagery onto certain objects is often undesirable Simple interface allows imagery to be replaced with illumination

11. 11 T. Johnson, H. Fuchs, “ A Unified Multi-Surface, Multi-Resolution Workspace” Camera-Based Scanning User selects copy area with selection window Selection window rendered as a single-surface window

12. 12 T. Johnson, H. Fuchs, “ A Unified Multi-Surface, Multi-Resolution Workspace” Camera-Based Scanning Remove perspective distortion using two-pass rendering Selection window P-matrix Camera Selection window

13. 13 T. Johnson, H. Fuchs, “ A Unified Multi-Surface, Multi-Resolution Workspace” Video

14. 14 T. Johnson, H. Fuchs, “ A Unified Multi-Surface, Multi-Resolution Workspace” Contributions Two-pass rendering as a unifying framework for digital workspaces Image generation Rectified single surface imagery Perspectively correct multi-surface imagery Camera-based scanning Removal of perspective distortion LCD panel as a projector Simplifies calibration/rendering

15. 15 T. Johnson, H. Fuchs, “ A Unified Multi-Surface, Multi-Resolution Workspace” Future Work Automatic object illumination Camera-based detection of objects occluding projection Improved scanning resolution Trigger optical zoom, multi-camera super- resolution etc. Continuous calibration Online calibration monitoring and refinement

16. 16 T. Johnson, H. Fuchs, “ A Unified Multi-Surface, Multi-Resolution Workspace” Thank You Funding support: ONR N00014-03-1-0589 DARWARS Training Superiority program VIRTE – Virtual Technologies and Environments program