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141.
Debevec, Paul; Tchou, Chris; Gardner, Andrew; Hawkins, Tim; Poullis, Charis; Stumpfel, Jessi; Jones, Andrew; Yun, Nathaniel; Einarsson, Per; Lundgren, Therese; Fajardo, Marcos; Martinez, Philippe
Estimating Surface Reflectance Properties of a Complex Scene under Captured Natural Illumination Technical Report
University of Southern California Institute for Creative Technologies no. ICT TR 06 2004, 2004.
@techreport{debevec_estimating_2004,
title = {Estimating Surface Reflectance Properties of a Complex Scene under Captured Natural Illumination},
author = {Paul Debevec and Chris Tchou and Andrew Gardner and Tim Hawkins and Charis Poullis and Jessi Stumpfel and Andrew Jones and Nathaniel Yun and Per Einarsson and Therese Lundgren and Marcos Fajardo and Philippe Martinez},
url = {http://ict.usc.edu/pubs/ICT-TR-06.2004.pdf},
year = {2004},
date = {2004-01-01},
number = {ICT TR 06 2004},
institution = {University of Southern California Institute for Creative Technologies},
abstract = {We present a process for estimating spatially-varying surface re- flectance of a complex scene observed under natural illumination conditions. The process uses a laser-scanned model of the scene's geometry, a set of digital images viewing the scene's surfaces under a variety of natural illumination conditions, and a set of correspond- ing measurements of the scene's incident illumination in each pho- tograph. The process then employs an iterative inverse global illu- mination technique to compute surface colors for the scene which, when rendered under the recorded illumination conditions, best re- produce the scene's appearance in the photographs. In our process we measure BRDFs of representative surfaces in the scene to better model the non-Lambertian surface reflectance. Our process uses a novel lighting measurement apparatus to record the full dynamic range of both sunlit and cloudy natural illumination conditions. We employ Monte-Carlo global illumination, multiresolution geome- try, and a texture atlas system to perform inverse global illumina- tion on the scene. The result is a lighting-independent model of the scene that can be re-illuminated under any form of lighting. We demonstrate the process on a real-world archaeological site, show- ing that the technique can produce novel illumination renderings consistent with real photographs as well as reflectance properties that are consistent with ground-truth reflectance measurements.},
keywords = {},
pubstate = {published},
tppubtype = {techreport}
}
We present a process for estimating spatially-varying surface re- flectance of a complex scene observed under natural illumination conditions. The process uses a laser-scanned model of the scene's geometry, a set of digital images viewing the scene's surfaces under a variety of natural illumination conditions, and a set of correspond- ing measurements of the scene's incident illumination in each pho- tograph. The process then employs an iterative inverse global illu- mination technique to compute surface colors for the scene which, when rendered under the recorded illumination conditions, best re- produce the scene's appearance in the photographs. In our process we measure BRDFs of representative surfaces in the scene to better model the non-Lambertian surface reflectance. Our process uses a novel lighting measurement apparatus to record the full dynamic range of both sunlit and cloudy natural illumination conditions. We employ Monte-Carlo global illumination, multiresolution geome- try, and a texture atlas system to perform inverse global illumina- tion on the scene. The result is a lighting-independent model of the scene that can be re-illuminated under any form of lighting. We demonstrate the process on a real-world archaeological site, show- ing that the technique can produce novel illumination renderings consistent with real photographs as well as reflectance properties that are consistent with ground-truth reflectance measurements.
142.
Debevec, Paul
Image-Based Techniques for Digitizing Environments and Artifacts Inproceedings
In: 4th International Conference on 3-D Digital Imaging and Modeling (3DIM), 2003.
@inproceedings{debevec_image-based_2003,
title = {Image-Based Techniques for Digitizing Environments and Artifacts},
author = {Paul Debevec},
url = {http://ict.usc.edu/pubs/Image-Based%20Techniques%20for%20Digitizing%20Environments%20and%20Artifacts.pdf},
year = {2003},
date = {2003-10-01},
booktitle = {4th International Conference on 3-D Digital Imaging and Modeling (3DIM)},
abstract = {This paper presents an overview of techniques for generating photoreal computer graphics models of real-world places and objects. Our group's early efforts in modeling scenes involved the development of Facade, an interactive photogrammetric modeling system that uses geometric primitives to model the scene, and projective texture mapping to produce the scene appearance properties. Subsequent work has produced techniques to model the incident illumination within scenes, which we have shown to be useful for realistically adding computer-generated objects to image-based models. More recently, our work has focussed on recovering lighting-independent models of scenes and objects, capturing how each point on an object reflects light. Our latest work combines three-dimensional range scans, digital photographs, and incident illumination measurements to produce lighting-independent models of complex objects and environments.},
keywords = {},
pubstate = {published},
tppubtype = {inproceedings}
}
This paper presents an overview of techniques for generating photoreal computer graphics models of real-world places and objects. Our group's early efforts in modeling scenes involved the development of Facade, an interactive photogrammetric modeling system that uses geometric primitives to model the scene, and projective texture mapping to produce the scene appearance properties. Subsequent work has produced techniques to model the incident illumination within scenes, which we have shown to be useful for realistically adding computer-generated objects to image-based models. More recently, our work has focussed on recovering lighting-independent models of scenes and objects, capturing how each point on an object reflects light. Our latest work combines three-dimensional range scans, digital photographs, and incident illumination measurements to produce lighting-independent models of complex objects and environments.
143.
Gardner, Andrew; Tchou, Chris; Hawkins, Tim; Debevec, Paul
Linear Light Source Reflectometry Inproceedings
In: ACM Transactions on Graphics, 2003.
@inproceedings{gardner_linear_2003,
title = {Linear Light Source Reflectometry},
author = {Andrew Gardner and Chris Tchou and Tim Hawkins and Paul Debevec},
url = {http://ict.usc.edu/pubs/Linear%20Light%20Source%20Reflectometry.pdf},
year = {2003},
date = {2003-01-01},
booktitle = {ACM Transactions on Graphics},
abstract = {This paper presents a technique for estimating the spatially-varying reflectance properties of a surface based on its appearance during a single pass of a linear light source. By using a linear light rather than a point light source as the illuminant, we are able to reliably observe and estimate the diffuse color, specular color, and specular roughness of each point of the surface. The reflectometry apparatus we use is simple and inexpensive to build, requiring a single direction of motion for the light source and a fixed camera viewpoint. Our model fitting technique first renders a reflectance table of how diffuse and specular reflectance lobes would appear under moving linear light source illumination. Then, for each pixel we compare its series of intensity values to the tabulated reflectance lobes to determine which reflectance model parameters most closely produce the observed reflectance values. Using two passes of the linear light source at different angles, we can also estimate per-pixel surface normals as well as the reflectance parameters. Additionally our system records a per-pixel height map for the object and estimates its per-pixel translucency. We produce real-time renderings of the captured objects using a custom hardware shading algorithm. We apply the technique to a test object exhibiting a variety of materials as well as to an illuminated manuscript with gold lettering. To demonstrate the technique's accuracy, we compare renderings of the captured models to real photographs of the original objects.},
keywords = {},
pubstate = {published},
tppubtype = {inproceedings}
}
This paper presents a technique for estimating the spatially-varying reflectance properties of a surface based on its appearance during a single pass of a linear light source. By using a linear light rather than a point light source as the illuminant, we are able to reliably observe and estimate the diffuse color, specular color, and specular roughness of each point of the surface. The reflectometry apparatus we use is simple and inexpensive to build, requiring a single direction of motion for the light source and a fixed camera viewpoint. Our model fitting technique first renders a reflectance table of how diffuse and specular reflectance lobes would appear under moving linear light source illumination. Then, for each pixel we compare its series of intensity values to the tabulated reflectance lobes to determine which reflectance model parameters most closely produce the observed reflectance values. Using two passes of the linear light source at different angles, we can also estimate per-pixel surface normals as well as the reflectance parameters. Additionally our system records a per-pixel height map for the object and estimates its per-pixel translucency. We produce real-time renderings of the captured objects using a custom hardware shading algorithm. We apply the technique to a test object exhibiting a variety of materials as well as to an illuminated manuscript with gold lettering. To demonstrate the technique's accuracy, we compare renderings of the captured models to real photographs of the original objects.
144.
Unger, J.; Wenger, Andreas; Hawkins, Tim; Gardner, Andrew; Debevec, Paul
Capturing and Rendering With Incident Light Fields Inproceedings
In: Proceedings of the 14th Eurographics workshop on Rendering, 2003.
@inproceedings{unger_capturing_2003,
title = {Capturing and Rendering With Incident Light Fields},
author = {J. Unger and Andreas Wenger and Tim Hawkins and Andrew Gardner and Paul Debevec},
url = {http://ict.usc.edu/pubs/Capturing%20and%20Rendering%20With%20Incident%20Light%20Fields.pdf},
year = {2003},
date = {2003-01-01},
booktitle = {Proceedings of the 14th Eurographics workshop on Rendering},
abstract = {This paper presents a process for capturing spatially and directionally varying illumination from a real-world scene and using this lighting to illuminate computer-generated objects. We use two devices for capturing such illumination. In the first we photograph an array of mirrored spheres in high dynamic range to capture the spatially varying illumination. In the second, we obtain higher resolution data by capturing images with an high dynamic range omnidirectional camera as it traverses across a plane. For both methods we apply the light field technique to extrapolate the incident illumination to a volume. We render computer-generated objects as illuminated by this captured illumination using a custom shader within an existing global illumination rendering system. To demonstrate our technique we capture several spatially-varying lighting environments with spotlights, shadows, and dappled lighting and use them to illuminate synthetic scenes. We also show comparisons to real objects under the same illumination.},
keywords = {},
pubstate = {published},
tppubtype = {inproceedings}
}
This paper presents a process for capturing spatially and directionally varying illumination from a real-world scene and using this lighting to illuminate computer-generated objects. We use two devices for capturing such illumination. In the first we photograph an array of mirrored spheres in high dynamic range to capture the spatially varying illumination. In the second, we obtain higher resolution data by capturing images with an high dynamic range omnidirectional camera as it traverses across a plane. For both methods we apply the light field technique to extrapolate the incident illumination to a volume. We render computer-generated objects as illuminated by this captured illumination using a custom shader within an existing global illumination rendering system. To demonstrate our technique we capture several spatially-varying lighting environments with spotlights, shadows, and dappled lighting and use them to illuminate synthetic scenes. We also show comparisons to real objects under the same illumination.
145.
Debevec, Paul; Wenger, Andreas; Tchou, Chris; Gardner, Andrew; Waese, Jamie; Hawkins, Tim
A Lighting Reproduction Approach to Live-Action Compositing Inproceedings
In: SIGGRAPH 2002, pp. 547–556, San Antonio, TX, 2002.
@inproceedings{debevec_lighting_2002,
title = {A Lighting Reproduction Approach to Live-Action Compositing},
author = {Paul Debevec and Andreas Wenger and Chris Tchou and Andrew Gardner and Jamie Waese and Tim Hawkins},
url = {http://ict.usc.edu/pubs/A%20Lighting%20Reproduction%20Approach%20to%20Live-Action%20Compositing.pdf},
year = {2002},
date = {2002-07-01},
booktitle = {SIGGRAPH 2002},
pages = {547--556},
address = {San Antonio, TX},
abstract = {We describe a process for compositing a live performance of an actor into a virtual set wherein the actor is consistently illuminated by the virtual environment. The Light Stage used in this work is a two-meter sphere of inward-pointing RGB light emitting diodes focused on the actor, where each light can be set to an arbitrary color and intensity to replicate a real-world or virtual lighting environment. We implement a digital two-camera infrared matting system to composite the actor into the background plate of the environment without affecting the visible-spectrum illumination on the actor. The color reponse of the system is calibrated to produce correct color renditions of the actor as illuminated by the environment. We demonstrate moving-camera composites of actors into real-world environments and virtual sets such that the actor is properly illuminated by the environment into which they are composited.},
keywords = {},
pubstate = {published},
tppubtype = {inproceedings}
}
We describe a process for compositing a live performance of an actor into a virtual set wherein the actor is consistently illuminated by the virtual environment. The Light Stage used in this work is a two-meter sphere of inward-pointing RGB light emitting diodes focused on the actor, where each light can be set to an arbitrary color and intensity to replicate a real-world or virtual lighting environment. We implement a digital two-camera infrared matting system to composite the actor into the background plate of the environment without affecting the visible-spectrum illumination on the actor. The color reponse of the system is calibrated to produce correct color renditions of the actor as illuminated by the environment. We demonstrate moving-camera composites of actors into real-world environments and virtual sets such that the actor is properly illuminated by the environment into which they are composited.
146.
Debevec, Paul
A Tutorial on Image-Based Lighting Journal Article
In: IEEE Computer Graphics and Applications, 2002.
@article{debevec_tutorial_2002,
title = {A Tutorial on Image-Based Lighting},
author = {Paul Debevec},
url = {http://ict.usc.edu/pubs/Image-Based%20Lighting.pdf},
year = {2002},
date = {2002-01-01},
journal = {IEEE Computer Graphics and Applications},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
147.
Cohen, Jonathan; Tchou, Chris; Hawkins, Tim; Debevec, Paul
Real-Time High-Dynamic Range Texture Mapping Inproceedings
In: Eurographics Rendering Workshop, 2001.
@inproceedings{cohen_real-time_2001,
title = {Real-Time High-Dynamic Range Texture Mapping},
author = {Jonathan Cohen and Chris Tchou and Tim Hawkins and Paul Debevec},
url = {http://ict.usc.edu/pubs/Real-Time%20High-Dynamic%20Range%20Texture%20Mapping.pdf},
year = {2001},
date = {2001-06-01},
booktitle = {Eurographics Rendering Workshop},
abstract = {This paper presents a technique for representing and displaying high dynamic-range texture maps (HDRTMs) using current graphics hardware. Dynamic range in real-world environments often far exceeds the range representable in 8-bit per-channel texture maps. The increased realism afforded by a high-dynamic range representation provides improved fidelity and expressiveness for interactive visualization of image-based models. Our technique allows for real-time rendering of scenes with arbitrary dynamic range, limited only by available texture memory. In our technique, high-dynamic range textures are decomposed into sets of 8- bit textures. These 8-bit textures are dynamically reassembled by the graphics hardware's programmable multitexturing system or using multipass techniques and framebuffer image processing. These operations allow the exposure level of the texture to be adjusted continuously and arbitrarily at the time of rendering, correctly accounting for the gamma curve and dynamic range restrictions of the display device. Further, for any given exposure only two 8-bit textures must be resident in texture memory simultaneously. We present implementation details of this technique on various 3D graphics hardware architectures. We demonstrate several applications, including high-dynamic range panoramic viewing with simulated auto-exposure, real-time radiance environment mapping, and simulated Fresnel reflection.},
keywords = {},
pubstate = {published},
tppubtype = {inproceedings}
}
This paper presents a technique for representing and displaying high dynamic-range texture maps (HDRTMs) using current graphics hardware. Dynamic range in real-world environments often far exceeds the range representable in 8-bit per-channel texture maps. The increased realism afforded by a high-dynamic range representation provides improved fidelity and expressiveness for interactive visualization of image-based models. Our technique allows for real-time rendering of scenes with arbitrary dynamic range, limited only by available texture memory. In our technique, high-dynamic range textures are decomposed into sets of 8- bit textures. These 8-bit textures are dynamically reassembled by the graphics hardware's programmable multitexturing system or using multipass techniques and framebuffer image processing. These operations allow the exposure level of the texture to be adjusted continuously and arbitrarily at the time of rendering, correctly accounting for the gamma curve and dynamic range restrictions of the display device. Further, for any given exposure only two 8-bit textures must be resident in texture memory simultaneously. We present implementation details of this technique on various 3D graphics hardware architectures. We demonstrate several applications, including high-dynamic range panoramic viewing with simulated auto-exposure, real-time radiance environment mapping, and simulated Fresnel reflection.
148.
Waese, Jamie; Debevec, Paul
A Real Time High Dynamic Range Light Probe Inproceedings
In: SIGGRAPH Technical Sketches, 2001.
@inproceedings{waese_real_2001,
title = {A Real Time High Dynamic Range Light Probe},
author = {Jamie Waese and Paul Debevec},
url = {http://ict.usc.edu/pubs/A%20Real%20Time%20High%20Dynamic%20Range%20Light%20Probe.pdf},
year = {2001},
date = {2001-01-01},
booktitle = {SIGGRAPH Technical Sketches},
keywords = {},
pubstate = {published},
tppubtype = {inproceedings}
}
149.
Hawkins, Tim; Cohen, Jonathan; Tchou, Chris; Debevec, Paul
Light Stage 2.0 Inproceedings
In: SIGGRAPH Technical Sketches, pp. 217, 2001.
@inproceedings{hawkins_light_2001,
title = {Light Stage 2.0},
author = {Tim Hawkins and Jonathan Cohen and Chris Tchou and Paul Debevec},
url = {http://ict.usc.edu/pubs/Light%20Stage%202.pdf},
year = {2001},
date = {2001-01-01},
booktitle = {SIGGRAPH Technical Sketches},
pages = {217},
keywords = {},
pubstate = {published},
tppubtype = {inproceedings}
}
150.
Hawkins, Tim; Cohen, Jonathan; Debevec, Paul
A Photometric Approach to Digitizing Cultural Artifacts Inproceedings
In: Proceedings of 2nd International Symposium on Virtual Reality, Archaeology and Cultural Heritage, Glyfada, Greece, 2001.
@inproceedings{hawkins_photometric_2001,
title = {A Photometric Approach to Digitizing Cultural Artifacts},
author = {Tim Hawkins and Jonathan Cohen and Paul Debevec},
url = {http://ict.usc.edu/pubs/A%20Photometric%20Approach%20to%20Digitizing%20Cultural%20Artifacts.pdf},
year = {2001},
date = {2001-01-01},
booktitle = {Proceedings of 2nd International Symposium on Virtual Reality, Archaeology and Cultural Heritage},
address = {Glyfada, Greece},
abstract = {In this paper we present a photometry-based approach to the digital documentation of cultural artifacts. Rather than representing an artifact as a geometric model with spatially varying reflectance properties, we instead propose directly representing the artifact in terms of its reflectance field - the manner in which it transforms light into images. The principal device employed in our technique is a computer-controlled lighting apparatus which quickly illuminates an artifact from an exhaustive set of incident illumination directions and a set of digital video cameras which record the artifact's appearance under these forms of illumination. From this database of recorded images, we compute linear combinations of the captured images to synthetically illuminate the object under arbitrary forms of complex incident illumination, correctly capturing the effects of specular reflection, subsurface scattering, self-shadowing, mutual illumination, and complex BRDF's often present in cultural artifacts. We also describe a computer application that allows users to realistically and interactively relight digitized artifacts.},
keywords = {},
pubstate = {published},
tppubtype = {inproceedings}
}
In this paper we present a photometry-based approach to the digital documentation of cultural artifacts. Rather than representing an artifact as a geometric model with spatially varying reflectance properties, we instead propose directly representing the artifact in terms of its reflectance field - the manner in which it transforms light into images. The principal device employed in our technique is a computer-controlled lighting apparatus which quickly illuminates an artifact from an exhaustive set of incident illumination directions and a set of digital video cameras which record the artifact's appearance under these forms of illumination. From this database of recorded images, we compute linear combinations of the captured images to synthetically illuminate the object under arbitrary forms of complex incident illumination, correctly capturing the effects of specular reflection, subsurface scattering, self-shadowing, mutual illumination, and complex BRDF's often present in cultural artifacts. We also describe a computer application that allows users to realistically and interactively relight digitized artifacts.
151.
Debevec, Paul; Hawkins, Tim; Tchou, Chris; Duiker, Haarm-Pieter; Sarokin, Westley
Acquiring the Reflectance Field of a Human Face Inproceedings
In: SIGGRAPH, New Orleans, LA, 2000.
@inproceedings{debevec_acquiring_2000,
title = {Acquiring the Reflectance Field of a Human Face},
author = {Paul Debevec and Tim Hawkins and Chris Tchou and Haarm-Pieter Duiker and Westley Sarokin},
url = {http://ict.usc.edu/pubs/Acquiring%20the%20Re%EF%AC%82ectance%20Field%20of%20a%20Human%20Face.pdf},
year = {2000},
date = {2000-07-01},
booktitle = {SIGGRAPH},
address = {New Orleans, LA},
abstract = {We present a method to acquire the reflectance field of a human face and use these measurements to render the face under arbitrary changes in lighting and viewpoint. We first acquire images of the face from a small set of viewpoints under a dense sampling of incident illumination directions using a light stage. We then construct a reflectance function image for each observed image pixel from its values over the space of illumination directions. From the reflectance functions, we can directly generate images of the face from the original viewpoints in any form of sampled or computed illumination. To change the viewpoint, we use a model of skin reflectance to estimate the appearance of the reflectance functions for novel viewpoints. We demonstrate the technique with synthetic renderings of a person's face under novel illumination and viewpoints.},
keywords = {},
pubstate = {published},
tppubtype = {inproceedings}
}
We present a method to acquire the reflectance field of a human face and use these measurements to render the face under arbitrary changes in lighting and viewpoint. We first acquire images of the face from a small set of viewpoints under a dense sampling of incident illumination directions using a light stage. We then construct a reflectance function image for each observed image pixel from its values over the space of illumination directions. From the reflectance functions, we can directly generate images of the face from the original viewpoints in any form of sampled or computed illumination. To change the viewpoint, we use a model of skin reflectance to estimate the appearance of the reflectance functions for novel viewpoints. We demonstrate the technique with synthetic renderings of a person's face under novel illumination and viewpoints.
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