Greg Welch

Publication List Details

Period

1995 - 2009

Number

75

Co-Authors

Abstract Achieving Color Uniformity Across Multi-Projector Displays (2009)

Aditi Majumder, Zhu He, Herman Towles, Greg Welch

Large area tiled displays are gaining popularity for use in collaborative immersive virtual environments and scientific visualization. While recent work has addressed the issues of geometric...

Emerging Display Technologies—New Systems and Applications From Images to Sensing, Interaction and Enhancement (2008)

Andreas Simon, Greg Welch, Mark Bolas

The recent flurry of display technology development has produced families of technologies that make fixed and projected pixels cheaper, faster, more flexible, and of higher quality. These advances...

Differential Camera Tracking through Linearizing the Local Appearance Manifold (2008)

Hua Yang, Marc Pollefeys, Greg Welch, Jan-michael Frahm, Adrian Ilie

The appearance of a scene is a function of the scene contents, the lighting, and the camera pose. A set of n-pixel images of a non-degenerate scene captured from different perspectives lie on a 6D...

Volume xx (200y), Number z, pp. 1–9 Abstract Real-Time Consensus-Based Scene Reconstruction using Commodity Graphics Hardware (2008)

Ruigang Yang, Greg Welch, Gary Bishop

We present a novel use of commodity graphics hardware that effectively combines a plane-sweeping algorithm with view synthesis for real-time, on-line 3D scene acquisition and view synthesis. Using...

Abstract The Office of the Future: A Unified Approach to Image-Based Modeling and Spatially Immersive Displays (2008)

Ramesh Raskar, Greg Welch, Matt Cutts, Adam Lake, Lev Stesin, Henry Fuchs

We introduce ideas, proposed technologies, and initial results for an office of the future that is based on a unified application of computer vision and computer graphics in a system that combines...

Differential Camera Tracking through Linearizing the Local Appearance Manifold (2008)

Hua Yang, Marc Pollefeys, Greg Welch, Jan-michael Frahm, Adrian Ilie

The appearance of a scene is a function of the scene contents, the lighting, and the camera pose. A set of n-pixel images of a non-degenerate scene captured from different perspectives lie on a 6D...

Improving, Expanding and Extending 3D Telepresence Abstract (2008)

Greg Welch, Henry Fuchs, Bruce Cairns, Ketan Mayer-patel, Diane H. Sonnenwald, Ruigang Yang, ...

For over a decade we have been pursuing a vision of threedimensional (3D) telepresence. Our primary driving problem is 3D medical consultation. Our basic goal is to enhance and expand medical...

Differential Camera Tracking through Linearizing the Local Appearance Manifold (2008)

Hua Yang, Marc Pollefeys, Greg Welch, Jan-michael Frahm, Adrian Ilie

The appearance of a scene is a function of the scene contents, the lighting, and the camera pose. A set of n-pixel images of a non-degenerate scene captured from different perspectives lie on a 6D...

Motion Tracking Survey Motion Tracking: No Silver Bullet, but a Respectable Arsenal (2008)

Greg Welch, Eric Foxlin

If you read the surveys of motion tracking systems, 1-5 one thing that will immediately strike you is the number of technologies and approaches—a bewildering array of systems operating on entirely...

Motion Tracking Survey Motion Tracking: No Silver Bullet, but a Respectable Arsenal (2008)

Greg Welch, Eric Foxlin

If you read the surveys of motion tracking systems, 1-5 one thing that will immediately strike you is the number of technologies and approaches—a bewildering array of systems operating on entirely...

Experimental Comparison of 2D and 3D Technology Mediated Paramedic-Physician Collaboration in Remote Emergency Medical Situations (2008)

Diane H. Sonnenwald, Hanna Maurin, Bruce Cairns, James E. Manning, Eugene B. Freid, Greg Welch, ...

We are investigating the potential of 3D telepresence technology to support collaboration among geographically separated medical personnel in trauma emergency care situations. 3D telepresence...

GPU-Based View Synthesis Using an Orbital Reconstruction Frustum (2008)

Greg Welch

Figure 1: Conceptual sketches of some threedimensional (3D) medical telepresence paradigms. Left: a portable multi-camera unit. Right: hospitalbased 3D viewing. (Sketches by Andrei State.) 1.

Model-Based 3D Object Tracking Using an Extended-Extended Kalman Filter and Graphics Rendered Measurements (2008)

Hua Yang, Greg Welch

This paper presents a model-based 3D object tracking system that uses an improved Extended Kalman filter (EKF) with graphics rendering as the measurement function. During tracking, features are...

ABSTRACT Measurement Sample Time Optimization for Human Motion Tracking/Capture Systems (2008)

Greg Welch, Adrian Ilie

Many human motion tracking systems average, integrate, or correlate device samples over some non-zero period of time in order to produce a single system-level measurement. This is done to reduce the...

Immersive Electronic Books for Teaching Surgical Procedures (2008)

Andries Van Dam, Greg Welch

This paper reports on early progress with the use of immersive virtual reality technology for trauma surgery training. We discuss our technical goals and the application area, and then describe our...

A Stochastic Quality Metric for Optimal Control of Active Camera Network Configurations for 3D Computer Vision Tasks (2008)

Ilie, Adrian, Welch, Greg, Macenko, Marc

We present a stochastic state-space quality metric for use in controlling active camera networks aimed at 3D vision tasks such as surveillance, motion tracking, and 3D shape/appearance...

A Stochastic Quality Metric for Optimal Control of Active Camera Network Configurations for 3D Computer Vision Tasks (2008)

Ilie, Adrian, Welch, Greg, Macenko, Marc

We present a stochastic state-space quality metric for use in controlling active camera networks aimed at 3D vision tasks such as surveillance, motion tracking, and 3D shape/appearance...

08231 Abstracts Collection -- Virtual Realities (2008)

Brunnett, Guido, Coquillart, Sabine, Welch, Greg

From 1st to 6th June 2008, the Dagstuhl Seminar 08231 ``Virtual Realities'' was held in the International Conference and Research Center (IBFI), Schloss Dagstuhl. Virtual Reality (VR) is a...

One-Step-at-a-Time Tracking (2007)

Greg Welch, Gary Bishop

We introduce a new mathematical method for tracking position and orientation. The method, which is applicable to a wide variety of virtual-environment tracking systems, offers several advantages: (1)...

Immersive Electronic Books for Teaching Surgical Procedures (2007)

Andries Van Dam, Greg Welch

This paper reports on early progress with the use of immersive virtual reality technology for trauma surgery training. We discuss our technical goals and the application area, and then describe our...

Optical Tracking (2007)

Greg Welch, Gary Bishop, Leandra Vicci, Stephen Brumback, Kurtis Keller

Since the early 1980s, the Tracker Project at the University of North Carolina at Chapel Hill has been working on wide-area head tracking for virtual and augmented environments. Our long-term goal...

Large Displays Projected Imagery in Your “Office of (2007)

The Future, Andrei State, Greg Welch, Henry Fuchs, Ramesh Raskar, Herman Towles, ...

In July 1998 we presented a long-term vision for a project we call the “Office of the Future ” at ACM Siggraph 98. 1 Our dream, depicted in Figure 1, is that some day your office will have...

Eurographics Workshop on Rendering Efficient Image Generation for Multiprojector and Multisurface Displays 1 Efficient Image Generation for (2007)

Multisurface Displays, Ramesh Raskar, Matt Cutts, Greg Welch, Wolfgang Strzlinger

Abstract. We describe an efficient approach to rendering a perspectively correct image on a potentially irregular display surface that may be illuminated with one or more distinct devices. The first...

Large Displays Working in the Office of “Real Soon Now” The “Office of Real Soon Now ” is an ongoing (2007)

Gary Bishop, Greg Welch

experiment to see what it’s like to use large-screen projection as our only computer display. We say “real soon now ” to contrast our experiment with the “Office of the Future, ” a...

Abstract The Office of the Future: A Unified Approach to Image-Based Modeling and Spatially Immersive Displays (2007)

Ramesh Raskar, Greg Welch, Matt Cutts, Adam Lake, Lev Stesin, Henry Fuchs

We introduce ideas, proposed technologies, and initial results for an office of the future that is based on a unified application of computer vision and computer graphics in a system that combines...

IS (2007)

Ramesh Raskar, Kok-lim Low, Greg Welch

UNC is an Equal Opportunity/Affirmative Action Institution. We describe a new paradigm for three-dimensional computer graphics, using projectors to graphically animate physical objects in the real...

Complementary tracking and two-handed interaction for remote 3d medical consultation with a pda (2007)

Greg Welch

We report here on applying a complementary tracking and twohanded interaction paradigm to remote medical consultation using a mobile hand-held device. The basic idea is to track the relative pose...

Experimental comparison of 2D and 3D technology mediated paramedic-physician collaboration in remote emergency medical situations (2006)

Sonnenwald, Diane H., Maurin, Hanna, Cairns, Bruce, Manning, James E., Freid, Eugene B., Welch, Greg, ...

We are investigating the potential of 3D telepresence technology to support collaboration among geographically separated medical personnel in trauma emergency care situations. 3D telepresence...

Experimental Comparison of 2D and 3D Technology Mediated Paramedic-Physician Collaboration in Remote Emergency Medical Situations (2006)

Sonnenwald, Diane H., Maurin, Hanna, Cairns, Bruce, Manning, James E., Freid, Eugene B., Welch, Greg, ...

We are investigating the potential of 3D telepresence technology to support collaboration among geographically separated medical personnel in trauma emergency care situations. 3D telepresence...

Experimental Comparison of 2D and 3D Technology Mediated Paramedic-Physician Collaboration in Remote Emergency Medical Situations (2006)

Sonnenwald, Diane H., Maurin, Hanna, Cairns, Bruce, Manning, James E., Freid, Eugene B., Welch, Greg, ...

We are investigating the potential of 3D telepresence technology to support collaboration among geographically separated medical personnel in trauma emergency care situations. 3D telepresence...

An interactive camera placement and visibility simulator for image-based vr applications (2006)

Andrei State, Greg Welch, Adrian Ilie

We describe an interactive software simulator that assists with the design of multi-camera setups for applications such as image-based virtual reality, three-dimensional reconstruction from still or...

A general method for comparing the expected performance of tracking and motion capture systems (2005)

B. Danette Allen, Greg Welch

We introduce a general method for evaluating and comparing the expected performance of sensing systems for interactive computer graphics. Example applications include head tracking systems for...

A general method for comparing the expected performance of tracking and motion capture systems (2005)

B. Danette Allen, Greg Welch

We introduce a general method for evaluating and comparing the expected performance of sensing systems for interactive computer graphics. Example applications include head tracking systems for...

Ensuring Color Consistency across Multiple Cameras (2005)

Adrian Ilie, Greg Welch

Most multi-camera vision applications assume a single common color response for all cameras. However different cameras—even of the same type—can exhibit radically different color responses, and...

Remote 3D medical consultation (2005)

Greg Welch, Diane H. Sonnenwald, Ketan Mayer-patel, Ruigang Yang, Andrei State, Herman Towles, ...

Abstract — Two-dimensional (2D) video-based telemedical consultation has been explored widely in the past 15– 20 years. Two issues that seem to arise in most relevant case studies are the...

A unified approach to real-time, multi-resolution, multi-baseline 2d view synthesis and 3d depth estimation using commodity graphics hardware (2004)

Ruigang Yang, Marc Pollefeys, Hua Yang, Greg Welch

We present a new method for using commodity graphics hardware to achieve real-time, on-line, 2D view synthesis or 3D depth estimation from two or more calibrated cameras. Our method combines a 3D...

A Unified Approach to Real-Time, (2004)

Ruigang Yang, Marc Pollefeys, Hua Yang, Greg Welch

We present a new method for using commodity graphics hardware to achieve real-time, on-line, 2D view synthesis or 3D depth estimation from two or more calibrated cameras. Our method combines a 3D...

3d telepresence for off-line surgical training and on-line remote consultation (2004)

Greg Welch, Ruigang Yang, Bruce Cairns, Herman Towles, Dan Russo, ...

We present an overview of multi-year efforts aimed at developing technology to support natural telepresence over time for off-line surgical training, and over space for on-line or “live ” remote...

Combining head-mounted and projector-based displays for surgical training (2003)

Kok-lim Low, Adrian Ilie, Greg Welch, Anselmo Lastra

We introduce and present preliminary results for a hybrid display system combining head-mounted and projector-based displays. Our work is motivated by a surgical training application, where it is...

Combining head-mounted and projector-based displays for surgical training (2003)

Kok-lim Low, Adrian Ilie, Greg Welch, Anselmo Lastra

We introduce and present preliminary results for a hybrid display system combining head-mounted and projector-based displays. Our work is motivated by a surgical training application, where it is...

Dealing with textureless regions and specular highlights: A progressive space carving scheme using a novel photo-consistency measure (2003)

Ruigang Yang, Marc Pollefeys, Greg Welch

We present two extensions to the Space Carving framework. The first is a progressive scheme to better reconstruct surfaces lacking sufficient textures. The second is a novel photo-consistency measure...

Dealing with textureless regions and specular highlights: A progressive space carving scheme using a novel photo-consistency measure (2003)

Ruigang Yang, Marc Pollefeys, Greg Welch

We present two extensions to the Space Carving framework. The first is a progressive scheme to better reconstruct surfaces lacking sufficient textures. The second is a novel photo-consistency measure...

Fast image segmentation and smoothing using commodity graphics hardware (2002)

Ruigang Yang, Greg Welch

Abstract. We present a novel use of commodity graphics hardware to perform real-time image segmentation and image morphology operations. Our preliminary results show a performance increase of over 30...

Life-Sized Projector-Based Dioramas (2001)

Kok-lim Low, Greg Welch, Anselmo Lastra, Henry Fuchs

We introduce an idea and some preliminary results for a new projector-based approach to re-creating real and imagined sites. Our goal is to achieve re-creations that are both visually and spatially...

Computer graphics optique: Optical superposition of projected computer graphics (2001)

Aditi Majumder, Greg Welch

Abstract. We present some ideas and demonstrations for a hybrid projectorbased rendering and display technique we call Computer Graphics Optique. Instead of partially overlapping projected images to...

Automatic and Continuous Projector Display Surface Calibration Using Every-Day Imagery (2001)

Ruigang Yang, Greg Welch

Projector-based display systems have been used in computer graphics for about as long as the field has existed. While projector-based systems have many advantages, a significant disadvantage is the...

Life-Sized Projector-Based Dioramas (2001)

Kok-lim Low, Greg Welch, Anselmo Lastra, Henry Fuchs

We introduce an idea and some preliminary results for a new projector-based approach to re-creating real and imagined sites. Our goal is to achieve re-creations that are both visually and spatially...

Automatic Projector Display Surface Estimation Using Every-Day Imagery (2001)

Ruigang Yang, Greg Welch

Projector-based display systems have been used in computer graphics for about as long as the field has existed. While projector-based systems have many advantages, a significant disadvantage is the...

Highperformance wide-area optical tracking: The HiBall tracking system. Teleoperators and Virtual Environments (2001)

Greg Welch, Gary Bishop, Ra Vicci, Stephen Brumback, Kurtis Keller, Maple Place

Since the early 1980’s the Tracker Project at the University of North Carolina at Chapel Hill has been working on wide-area head tracking for Virtual and Augmented Environments. Our longterm goal...

Mitsubishi Electric Research Laboratories (2001)

Http Www Merl, Ramesh Raskar, Greg Welch, Kok-lim Low, Deepak Bandyopadhyay

this paper, we have mainly focussed on the visualization aspect, but a more detailed study of human interaction and issues is necessary

SIGGRAPH 2001 Course 11 (2001)

Tracking Beyond Minutes, B. Danette Allen, Greg Welch

This report and other useful material can be found at the authors' Kalman filter web site, http://www.cs.unc.edu/~welch/kalman/

Computer graphics optique: Optical superposition of projected computer graphics (2001)

Aditi Majumder, Greg Welch

Abstract. We present some ideas and demonstrations for a hybrid projectorbased rendering and display technique we call Computer Graphics Optique. Instead of partially overlapping projected images to...

Toward a Compelling Sensation of Telepresence: Demonstrating a portal to a distant (static) office (2000)

Wei-chao Chen, Herman Towles, Lars Nyland, Greg Welch, Henry Fuchs

In 1998 we introduced the idea for a project we call the Office of the Future. Our long-term vision is to provide a better every-day working environment, with high-fidelity scene reconstruction for...

Achieving Color Uniformity Across Multi-Projector Displays (2000)

Aditi Majumder, Zhu He, Herman Towles, Greg Welch

Large area tiled displays are gaining popularity for use in collaborative immersive virtual environments and scientific visualization. While recent work has addressed the issues of geometric...

Table-Top Spatially-Augmented Reality: Bringing Physical Models to Life with Projected Imagery (1999)

Ramesh Raskar, Greg Welch, Wei-chao Chen

Despite the availability of high-quality graphics systems, architects and designers still build scaled physical models of buildings and products. These physical models have many advantages, however...

Multi-Projector Displays Using Camera-Based Registration (1999)

Ramesh Raskar, Michael Brown, Ruigang Yang, Wei-chao Chen, Greg Welch, Herman Towles, ...

Conventional projector-based display systems are typically designed around precise and regular configurations of projectors and display surfaces. While this results in rendering simplicity and speed,...

Table-Top Spatially-Augmented Reality: Bringing Physical Models to Life with Projected Imagery (1999)

Ramesh Raskar, Greg Welch, Wei-Chao Chen

Despite the availability of high-quality graphics systems, architects and designers still build scaled physical models of buildings and products. These physical models have many advantages, however...

The HiBall Tracker: High-Performance Wide-Area Tracking for Virtual and Augmented Environments (1999)

Greg Welch, Gary Bishop, Ra Vicci, Stephen Brumback, Kurtis Keller

Our HiBall Tracking System generates over 2000 head-pose estimates per second with less than one millisecond of latency, and less than 0.5 millimeters and 0.02 degrees of position and orientation...

Multi-Projector Displays Using Camera-Based Registration (1999)

Ramesh Raskar, Michael Brown, Ruigang Yang, Wei-chao Chen, Greg Welch, Herman Towles, ...

Conventional projector-based display systems are typically designed around precise and regular configurations of projectors and display surfaces. While this results in rendering simplicity and speed,...

Efficient Image Generation for Multiprojector and Multisurface Displays (1998)

Ramesh Raskar, Matt Cutts, Greg Welch, Wolfgang Stüerzlinger

Abstract. We describe an efficient approach to rendering a perspectively correct image for a single eye point, on a potentially irregular display surface that is illuminated with one or more distinct...

Seamless Projection Overlaps Using Image Warping and Intensity Blending (1998)

Ramesh Raskar, Greg Welch, Henry Fuchs

Abstract. High-resolution Spatially Immersive Displays (SID) generally involve wide field of view (WFOV) image generation using multiple projectors. This paper describes a robust calibration and...

Spatially Augmented Reality (1998)

Ramesh Raskar, Greg Welch, Henry Fuchs

To create an effective illusion of virtual objects coexisting with the real world, see-through HMD-based Augmented Reality techniques supplement the user's view with images of virtual objects....

Making augmented reality work outdoors requires hybrid tracking (1998)

Ronald T. Azuma, Bruce R. Hoff, Ronald Sarfaty, Michael J. Daily, Gary Bishop, ...

Developing Augmented Reality systems that work outdoors, rather than indoors in constrained environments, will open new application areas and motivate the construction of new, more general tracking...

Efficient Image Generation for Multiprojector and Multisurface Displays (1998)

Ramesh Raskar, Matt Cutts, Greg Welch, Wolfgang Stÿrzlinger

Abstract. We describe an efficient approach to rendering a perspectively correct image on a potentially irregular display surface that may be illuminated with one or more distinct devices. The first...

Efficient Image Generation for Multiprojector and Multisurface Displays (1998)

Ramesh Raskar, Matt Cutts, Greg Welch, Wolfgang Stürzlinger

We describe an efficient approach to rendering a perspectively correct image on a potentially irregular display surface that may be illuminated with one or more distinct devices. The first pass of...

Making Augmented Reality Work Outdoors Requires Hybrid Tracking (1998)

Ronald T. Azuma, Bruce R. Hoff, Ronald Sarfaty, Michael J. Daily, Gary Bishop, ...

Developing Augmented Reality systems that work outdoors, rather than indoors in constrained environments, will open new application areas and motivate the construction of new, more general tracking...

Spatially Augmented Reality (1998)

Ramesh Raskar, Greg Welch, Henry Fuchs

To create an effective illusion of virtual objects coexisting with the real world, see-through HMD-based Augmented Reality techniques supplement the user's view with images of virtual objects....

SCAAT: Incremental Tracking with Incomplete Information (1997)

Greg Welch, Gary Bishop

We present a promising new mathematical method for tracking a user's pose (position and orientation) for interactive computer graphics. The method, which is applicable to a wide variety of both...

SCAAT: Incremental Tracking with Incomplete Information (1997)

Greg Welch, Gary Bishop

We present a promising new mathematical method for tracking a user's pose (position and orientation) for interactive computer graphics. The method, which is applicable to a wide variety of both...

SCAAT: Incremental Tracking with Incomplete Information (1997)

Greg Welch, Gary Bishop

We present a promising new mathematical method for tracking a user's pose (position and orientation) for interactive computer graphics. The method, which is applicable to a wide variety of both...