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Charles R. Dyer's Home Page;Charles R. Dyer;Professor;Department of Computer Sciences;University of Wisconsin-Madison;1210 West Dayton Street;Madison,;Wisconsin;53706-1685 USA;E-mail: dyer@cs.wisc.edu;Telephone: (608) 262-1965;Fax: (608) 262-9777;Finger info;Ph.D., University of Maryland, 1979;(Curriculum Vitae);Areas of Interest:;Computer vision, three-dimensional shape representation,;appearance modeling, view synthesis, active vision, visualization;Group Leader, Wisconsin Computer Vision Group;Program Co-Chair, CVPR '96;Research Interests; View Synthesis;The goal of this work is to develop basic tools for controlling;in real-time, either autonomously or interactively, a virtual camera;of a real environment. The input is a set of images or video;streams, acquired from fixed or mobile cameras around a site,;and the output is a panoramic visualization of the scene in which;a virtual, user-controlled camera can be moved through the environment.;With this technology a user could interactively navigate through;a real environment, controlling a customized path of views of the;site that are not predetermined by the input images. The main research;question is how to adaptively combine a set of basis images to synthesize;new views of the scene without 3D models or 3D scene reconstruction;as an intermediate step. Recently we have developed an innovative;technique, which we call;view morphing,;that takes two basis;images and interpolates a continuous range of in-between images;corresponding to views on the linear path connecting the two camera centers.; Visual Exploration;Computer vision researchers have recently started to investigate how;to actively control the image acquisition process by controlling;camera parameters. We have been studying how to purposefully control the;position and orientation of a camera in order to dynamically adjust;viewpoint based on the appearance of a three-dimensional scene. The;use of real-time viewpoint-control behaviors is important for;solving tasks such as exploring an unknown object in order to find;specific surface markings, building a global model of an unknown;shape, or recognizing an object.;By coordinating simple observer behaviors that change the appearance;of surfaces in a well-defined way, we simplify the image computations;required, make precise the global progress of an algorithm, and;eliminate the need for accurate differential measurements of the;camera motion. We believe that this active approach of moving towards;viewpoints that are closely related to the geometry of the viewed;objects is a very important and general one. We have used this;approach to develop provably-correct algorithms for (1) moving to a;side view of a surface of revolution in order to recover its shape, and;(2) reconstructing the global surface of an unknown smooth,;arbitrarily-shaped object.; Visualization;In the area of visualization we have developed mapping techniques;capable of generating displays of all possible data objects defined in;a user's algorithm, without the need for user-defined, type-specific;graphics display procedures. This capability for displaying;arbitrary combinations of an algorithm's data objects in a common;frame of reference, coupled with interactive control of algorithm;execution, provides a powerful way to understand algorithm behavior,;especially interactive visual experiments with scientific data;analysis algorithms. We have implemented a system called VIS-AD for;experimenting with these techniques and have used it for visualizing;intermediate and final results of data analysis algorithms for;problems such as discriminating clouds in satellite images.;Recent Publications; S. M. Seitz and C. R. Dyer,; Cyclic motion analysis using the period trace,; in Motion-Based Recognition, M. Shah and; R. Jain, eds., Kluwer, Boston, to appear.; S. M. Seitz and C. R. Dyer,; View-invariant analysis of cyclic motion,; Int. J. Computer Vision, to appear.; S. M. Seitz and C. R. Dyer,;; View morphing,; Proc. SIGGRAPH 96, 1996, 21-30.; S. M. Seitz and C. R. Dyer,;; Toward image-based scene representation using view morphing,; Proc. 13th Int. Conf. Pattern Recognition, Vol. I, Track A:; Computer Vision, 1996, 84-89.; L. Yu and C. R. Dyer,;; Shape recovery from stationary surface contours by controlled observer motion, in; Advances in Image Understanding: A Festschrift for; Azriel Rosenfeld,; IEEE Computer Society Press, Los Alamitos, Ca., 1996, 177-193.; K. N. Kutulakos and C. R. Dyer,;; Global surface reconstruction by purposive control of observer motion,; Artificial Intelligence 78, No. 1-2, 1995, 147-177.; S. M. Seitz and C. R. Dyer,;; Complete scene reconstruction from four point correspondences,; Proc. 5th Int. Conf. Computer Vision, 1995, 330-337.; S. M. Seitz and C. R. Dyer,;; Physically-valid view synthesis by image interpolation,; Proc. Workshop on Representation of Visual Scenes,; 1995, 18-25.; K. N. Kutulakos and C. R. Dyer,;; Recovering shape by purposive viewpoint adjustment,; Int. J. Computer Vision 12, 1994, 113-136.; K. N. Kutulakos, W. B. Seales, and C. R. Dyer,;; Building global object models by purposive viewpoint control,; Proc. 2nd CAD-Based Vision Workshop,; 1994, 169-182.; K. N. Kutulakos, C. R. Dyer, and V. J. Lumelsky,;; Provable strategies for vision-guided exploration in three dimensions,; Proc. 1994 IEEE Int. Conf. Robotics and Automation,; 1994, 1365-1372.; K. N. Kutulakos and C. R. Dyer,;; Occluding contour detection using affine invariants and purposive; viewpoint control,; Proc. Computer Vision and Pattern Recognition Conf.,; 1994, 323-330.; S. M. Seitz and C. R. Dyer,;; Affine invariant detection of periodic motion,; Proc. Computer Vision and Pattern Recognition Conf.,; 1994, 970-975.; S. M. Seitz and C. R. Dyer,;; Detecting irregularities in cyclic motion,; Proc. Workshop on Motion of Non-Rigid and Articulated Objects,; 1994, 178-185.; W. L. Hibbard, B. E. Paul, A. L. Battaiola, D. A. Santek,; M-F. Voidrot-Martinez, and C. R. Dyer,;; Interactive visualization of earth and space science computations,; Computer 27, No. 7, July 1994, 65-72.; W. L. Hibbard, C. R. Dyer, and B. E. Paul,;; A lattice model for data display,; Proc. Visualization '94, 1994, 310-317.;Recent publications (including abstracts) by Wisconsin Computer Vision Group;Courses Taught; CS 540 - Introduction to Artificial Intelligence (Spring 1996, Fall 1996); CS 766 - Computer Vision (Fall 1995, Spring 1997);Current Ph.D. Students; Gareth Bestor; Brian Morgan; Steve Seitz; Liangyin Yu;Ph.D. Graduates;;Bill L. Hibbard, Ph.D. 1995;(whibbard@macc.wisc.edu);Visualizing Scientific Computations: A System based on;Lattice-Structured Data and Display Models;;Kiriakos N. Kutulakos, Ph.D. 1994;(kyros@cs.rochester.edu);Exploring Three-Dimensional Objects by Controlling the Point of;Observation;;Mark C. Allmen, Ph.D. 1991;(allmen@iutech.den.mmc.com);Image Sequence Description using Spatiotemporal Flow Curves:;Toward Motion-Based Recognition;;W. Brent Seales, Ph.D. 1991;(seales@dcs.uky.edu);Appearance Models of Three-Dimensional;Shape for Machine Vision and Graphics;;W. Harry Plantinga, Ph.D. 1988;(whp@wheaton.edu);The Asp: A Continuous, Viewer-Centered Object Representation;for Computer Vision;;Charles V. Stewart, Ph.D. 1988;(stewart@cs.rpi.edu);Connectionist Models of Stereo Vision;; Bradley P. Kjell, Ph.D. 1985;(kjell@ccsua.ctstateu.edu);Oriented Edge Separation Texture Measures;Links of Interest;My Bookmarks;