This Article 
 Bibliographic References 
 Add to: 
Projector Placement Planning for High Quality Visualizations on Real-World Colored Objects
November/December 2010 (vol. 16 no. 6)
pp. 1633-1641
Many visualization applications benefit from displaying content on real-world objects rather than on a traditional display (e.g., a monitor). This type of visualization display is achieved by projecting precisely controlled illumination from multiple projectors onto the real-world colored objects. For such a task, the placement of the projectors is critical in assuring that the desired visualization is possible. Using ad hoc projector placement may cause some appearances to suffer from color shifting due to insufficient projector light radiance being exposed onto the physical surface. This leads to an incorrect appearance and ultimately to a false and potentially misleading visualization. In this paper, we present a framework to discover the optimal position and orientation of the projectors for such projection-based visualization displays. An optimal projector placement should be able to achieve the desired visualization with minimal projector light radiance. When determining optimal projector placement, object visibility, surface reflectance properties, and projector-surface distance and orientation need to be considered. We first formalize a theory for appearance editing image formation and construct a constrained linear system of equations that express when a desired novel appearance or visualization is possible given a geometric and surface reflectance model of the physical surface. Then, we show how to apply this constrained system in an adaptive search to efficiently discover the optimal projector placement which achieves the desired appearance. Constraints can be imposed on the maximum radiance allowed by the projectors and the projectors' placement to support specific goals of various visualization applications. We perform several real-world and simulated appearance edits and visualizations to demonstrate the improvement obtained by our discovered projector placement over ad hoc projector placement.

[1] R. Azuma, Y. Baillot, R. Behringer, S. Feiner, S. Juliers, and B. MacIn- tyre, "Recent Advances in Augmented Reality", IEEE Computer Graphics and Applications, 21: 6, 34–47, 2001.
[2] D. Aliaga, A. Law, and Y. Yeung, "A Virtual Restoration Stage for Real-World Objects", ACM Trans. on Graphics, 27: 5, 2008.
[3] D. Bandyopadhyay, R. Raskar, and H. Fuchs, "Dynamic Shader Lamps: Painting on Movable Objects", Proc. of IEEE/ACM Intl. Symposium on Augmented Reality, 207–216, 2001.
[4] E. Bhasker, R. Juang, and A. Majumder, "Registration Techniques for Using Imperfect and Partially Calibrated Devices in Planar Multi-Projector Displays", IEEE Trans. On Visualization and Computer Graphics, 2007.
[5] E. Bhasker, P. Sinha, and A. Majumder, "Asynchronous Distributed Calibration for Scalable Reconfigurable Multi-Projector Displays", IEEE Trans. On Visualization and Computer Graphics, 2006.
[6] O. Bimber, B. Fröhlich, D. Schmalstieg, and L.M. Encarnação, "The Virtual Showcase", IEEE Computer Graphics & Applications, 21: 6, pp. 48–55, 2001.
[7] O. Bimber and D. Iwai, "Superimposing Dynamic Range", ACM Trans, on Graphics, 27: 5, 2008.
[8] H. Chen, R. Sukthankar, G. Wallace, and K. Li, "Scalable Alignment of Large-Format Multi-Projector Displays Using Camera Homography Trees", Proc. of IEEE Visualization, 2002.
[9] T.F. Coleman and Y. Li, "A Reflective Newton Method for Minimizing a Quadratic Function Subject to Bounds on Some of the Variables", SIAM Journal on Optimization, 6 (4), 1040–1058, 1996.
[10] Y. Chuang, D. Zongker, J. Hindorff, B. Curless, D. Salesin, and R. Szeliski, "Environment Matting Extensions: Towards Higher Accuracy and Real-Time Capture", Proc. of ACM SIGGRAPH, 121–130, 2000.
[11] N. Damera-Venkata and N. Chang, "Display Supersampling", ACM Trans. on Graphics, 28: 1, 2009.
[12] P. Debevec, Y. Yu, and G. Borshukov, "Efficient View-Dependent Image-Based Rendering with Projective Texture-Mapping", Eurographics Rendering Workshop, 105–116, 1998.
[13] R. Furukawa and H. Kawasaki, "Uncalibrated Multiple Image Stereo System with Arbitrarily Movable Camera and Projector for Wide Range Scanning", Proc. of 3DIM, 302–309, 2005.
[14] A. Grundhöfer and O. Bimber, "Real-time Adaptive Radiometric Compensation", IEEE Trans. on Visualization and Computer Graphics, 14: 1, 97–108, 2008.
[15] Z. Gigus and J. Malik, "Computing the aspect graph for line drawings of polyhedral objects", IEEE Trans. on Pattern Analysis and Machine Intelligence, 12: 2, 113–122, 1990.
[16] M.D. Grossberg, H. Peri, S.K. Nayar, and P.N. Belhumeur, "Making One Object Look Like Another: Controlling Appearance using a Projector-Camera System", IEEE Conf. on Computer Vision and Pattern Recognition, 1: 452–459, 2004.
[17] M. Gross, S. Würmlin, M. Naef, E. Lamboray, C. Spagno, A. Kunz, E. Koller-Meier, T. Svoboda, L. Van Gool, S. Lang, K. Strehlke, A. Vande Moere, and O. Staadt, "blue-c: A Spatially Immersive Display and 3D Video Portal for Telepresence", Proc. of ACM SIGGRAPH, 819–827, 2003.
[18] T. Johnson and H. Fuchs, "A Unified Multi-Surface, Multi-Resolution Workspace with Camera-Based Scanning and Projector-Based Illumina tion", Eurographics Symp. on Virtual Environments-Immersive Projection Technology Workshop, 2007.
[19] A. Majumder, Z. He, H. Towles, and G. Welch, "Achieving Color Uniformity Across Multi-Projector Displays", 0Proc. Of IEEE Visualization, 2000.
[20] A. Majumder and R. Stevens, "Perceptual Photometric Seamlessness in Tiled Projection-Based Displays", ACM Trans. on Graphics, 2005.
[21] S.K. Nayar, H. Peri, M.D. Grossberg, and P.N. Belhumeur, "A Projection System with Radiometric Compensation for Screen Imperfections", Proc. of ICCV Workshop on Projector-Camera Systems, 2003.
[22] T. Okazaki, T. Okatani, and K. Deguchi, "Shape Reconstruction by Combination of Structured-Light Projection and Photometric Stereo Using a Projector-Camera System", Pacific Rim Symp. on Advances in Image and Video Technology, 410–422, 2009.
[23] J. O'Rourke, "Art Gallery Theorems and Algorithms", Oxford University Press, 1987.
[24] G. Pingali, C. Pinhanez, A. Levas, R. Kjeldsen, M. Podlaseck, H. Chen, and N. Sukaviriya, "Steerable Interfaces for Pervasive Computing Spaces", IEEE International Conf. on Pervasive Computing and Communications, 2003.
[25] R. Raskar, G. Welch, K.L. Low, and D. Bandyopadhyay, "Shader Lamps: Animating Real Objects With Image-Based Illumination", Proc. of Eurographics Workshop on Rendering Techniques, 89–102, 2001.
[26] B. Sajadi, M. Lazarov, A. Majumder, and M. Gopi, "Color Seamless-ness in Multi-Projector Displays Using Constrained Gamut Morphing", IEEE Trans. On Visualization and Computer Graphics, 2009.
[27] B. Sajadi and A. Majumder, "Auto-Calibration of Cylindrical Multi-Projector Systems", IEEE Virtual Reality, 2010.
[28] B. Sajadi and A. Majumder, "Markerless View-Independent Registration of Multiple Distorted Projectors on Vertically Extruded Surface Using a Single Uncalibrated Camera", IEEE Trans. on Visualization and Computer Graphics, 2009.
[29] W. Stuerzlinger, "Imaging all Visible Surfaces", Proc. of Graphics Interface, 115–122, 1999.
[30] W. Scott, G. Roth, and J.F. Rivest, "View planning for automated three-dimensional object reconstruction and inspection", ACM Computing Surveys, 35: 1, 64–96, 2003.
[31] D. Scharstein and R. Szeliski, "High-Accuracy Stereo Depth Maps Using Structured Light", IEEE Conf. on Computer Vision and Pattern Recognition, 195–202, 2003.
[32] G. Wetzstein and O. Bimber, "Radiometric Compensation Through Inverse Light Transport", Proc. of Pacific Graphics, 391–399, 2007.
[33] P. Wonka, M. Wimmer, K. Zhou, S. Maierhofer, G. Hesina, and A. Reshetov, "Guided Visibility Sampling", ACM Trans. on Graphics (SIGGRAPH), 25: 3, 494–502, 2006.
[34] M. Zwicker and J. Van Baar, "EWA Splatting", IEEE Trans. on Visualization and Computer Graphics, 8: 3, 223–238, 2002.

Index Terms:
large and High-resolution Displays, Interaction Design, Mobile and Ubiquitous Visualization
Alvin J. Law, Daniel G. Aliaga, Aditi Majumder, "Projector Placement Planning for High Quality Visualizations on Real-World Colored Objects," IEEE Transactions on Visualization and Computer Graphics, vol. 16, no. 6, pp. 1633-1641, Nov.-Dec. 2010, doi:10.1109/TVCG.2010.189
Usage of this product signifies your acceptance of the Terms of Use.