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24
The Lumigraph
 In Proceedings of SIGGRAPH 96
, 1996
"... This paper discusses a new method for capturing the complete appearanceof both synthetic and real world objects and scenes, representing this information, and then using this representation to render images of the object from new camera positions. Unlike the shape capture process traditionally used ..."
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Cited by 998 (41 self)
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This paper discusses a new method for capturing the complete appearanceof both synthetic and real world objects and scenes, representing this information, and then using this representation to render images of the object from new camera positions. Unlike the shape capture process traditionally used in computer vision and the rendering process traditionally used in computer graphics, our approach does not rely on geometric representations. Instead we sample and reconstruct a 4D function, which we call a Lumigraph. The Lumigraph is a subset of the complete plenoptic function that describes the flow of light at all positions in all directions. With the Lumigraph, new images of the object can be generated very quickly, independent of the geometric or illumination complexity of the scene or object. The paper discusses a complete working system including the capture of samples, the construction of the Lumigraph, and the subsequent rendering of images from this new representation. 1
Radiance caching for efficient global illumination computation
 IEEE TVCG
, 2005
"... Abstract—In this paper, we present a ray tracingbased method for accelerated global illumination computation in scenes with lowfrequency glossy BRDFs. The method is based on sparse sampling, caching, and interpolating radiance on glossy surfaces. In particular, we extend the irradiance caching sch ..."
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Cited by 33 (8 self)
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Abstract—In this paper, we present a ray tracingbased method for accelerated global illumination computation in scenes with lowfrequency glossy BRDFs. The method is based on sparse sampling, caching, and interpolating radiance on glossy surfaces. In particular, we extend the irradiance caching scheme proposed by Ward et al. [1] to cache and interpolate directional incoming radiance instead of irradiance. The incoming radiance at a point is represented by a vector of coefficients with respect to a hemispherical or spherical basis. The surfaces suitable for interpolation are selected automatically according to the roughness of their BRDF. We also propose a novel method for computing translational radiance gradient at a point. Index Terms—Global illumination, ray tracing, hemispherical harmonics, spherical harmonics, directional distribution. 1
Radiance Caching for Efficient Global Illumination
 IEEE Transactions on Visualization and Computer Graphics
, 2005
"... In this paper we present a ray tracing based method for accelerated global illumination computation in scenes with lowfrequency glossy BRDFs. The method is based on sparse sampling, caching, and interpolating radiance on glossy surfaces. In particular we extend the irradiance caching scheme propose ..."
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Cited by 24 (2 self)
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In this paper we present a ray tracing based method for accelerated global illumination computation in scenes with lowfrequency glossy BRDFs. The method is based on sparse sampling, caching, and interpolating radiance on glossy surfaces. In particular we extend the irradiance caching scheme proposed by Ward et al. [1] to cache and interpolate directional incoming radiance instead of irradiance. The incoming radiance at a point is represented by a vector of coefficients with respect to a spherical or hemispherical basis. The surfaces suitable for interpolation are selected automatically according to the roughness of their BRDF. We also propose a novel method for computing translational radiance gradient at a point.
Interactive Rendering of Wavelet Projected Light Fields
, 1999
"... Light field techniques allow the rendering of objects in time complexity unrelated to their geometric complexity. The technique discretely samples the space of light rays exiting the boundary around an object and then reconstructs a requested view from these data. In order to generate high quality i ..."
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Cited by 21 (0 self)
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Light field techniques allow the rendering of objects in time complexity unrelated to their geometric complexity. The technique discretely samples the space of light rays exiting the boundary around an object and then reconstructs a requested view from these data. In order to generate high quality images a dense sampling of the space is required which leads to large data sets. These data sets exhibit a high degree of coherence and should be compressed in order to make their size manageable. We present
Canned Lightsources
 In Eurographics Rendering Workshop
, 1998
"... . Complex luminaries and lamp geometries can greatly increase the realism of synthetic images. Unfortunately, the correct rendering of illumination from complex lamps requires costly global illumination algorithms to simulate the indirect illumination reflected or refracted by parts of the lamp. ..."
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Cited by 21 (8 self)
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. Complex luminaries and lamp geometries can greatly increase the realism of synthetic images. Unfortunately, the correct rendering of illumination from complex lamps requires costly global illumination algorithms to simulate the indirect illumination reflected or refracted by parts of the lamp. Currently, this simulation has to be repeated for every scene in which a lamp is to be used, and even for multiple instances of a lamp within a single scene. In this paper, we separate the global illumination simulation of the interior lamp geometry from the actual scene rendering. The lightfield produced by a given lamp is computed using any of the known global illumination algorithms. Afterwards, a discretized version of this lightfield is stored away for later use as a lightsource. We describe how this data can be efficiently utilized to illuminate a given scene using a number of different rendering algorithms, such as raytracing and hardwarebased rendering. 1 Introduction C...
Composite lighting simulations with lighting networks
 IEEE Computer Graphics and Applications
, 1998
"... ..."
BRDF Measurement Modelling using Wavelets for Efficient Path Tracing
 Computer Graphics Forum
, 2003
"... Physically based rendering needs numerical models from real measurements, or analytical models from material definitions, of the Bidirectional Reflectance Distribution Function (BRDF). However, measured BRDF data sets are too large and provide no functionalities to be practically used in Monte Carlo ..."
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Cited by 9 (2 self)
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Physically based rendering needs numerical models from real measurements, or analytical models from material definitions, of the Bidirectional Reflectance Distribution Function (BRDF). However, measured BRDF data sets are too large and provide no functionalities to be practically used in Monte Carlo path tracing algorithms. In this paper, we present a waveletbased generic BRDF model suitable for both physical analysis and path tracing. The model is based on the separation of spectral and geometrical aspect of the BRDF and allows a compact and efficient representation of isotropic, anisotropic and/or spectral BRDFs. After a brief survey of BRDF and wavelet theory, we present our software architecture for generic wavelet transform and how to use it to model BRDFs. Then, modelling results are presented on real and virtual BRDF measurements. Finally, we show how to exploit the multiresolution property of the wavelet encoding to reduce the variance by importance sampling in a path tracing algorithm. ACM CSS: I.3.7 Computer Graphics—ThreeDimensional Graphics and Realism 1.
Filtered Local Shading in the Wavelet Domain
 Rendering Techniques ’97 (Proceedings of the Eighth Eurographics Workshop on Rendering
, 1997
"... : Many global illumination algorithms generate directionallyand positionallyvarying radiance data that then need to be somehow resampled and used for final shading. This operation should filter all light over the incident hemisphere through the BRDF to generate an accurate image. This can be done ..."
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Cited by 8 (3 self)
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: Many global illumination algorithms generate directionallyand positionallyvarying radiance data that then need to be somehow resampled and used for final shading. This operation should filter all light over the incident hemisphere through the BRDF to generate an accurate image. This can be done analytically for simple BRDFs, such as Lambertian or Phonglike BRDFs, but becomes more difficult in the presence of a general BRDF. This paper presents an efficient method to calculate the reflected light in a given direction, filtering over all incident light directions. The method exploits wavelet representations of incident light and of the BRDF to compute the total relfected light in a given direction. For efficiency the incident light is restricted to a Haar transformed representation, while the BRDF can be represented and compressed with any appropriate basis. The method can be used with any system that can generate projections of incident light fields onto Haar wavelet bases. 1 Intr...
Wavelet Radiative Transfer and Surface Interaction
, 2002
"... Recently, there has been considerable interest in the representation of radiance in terms of wavelet basis functions. We will present a coordinate system called Nusselt coordinates which, when combined with wavelets, considerably simplifies computation of radiative transport and surface interaction. ..."
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Cited by 4 (1 self)
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Recently, there has been considerable interest in the representation of radiance in terms of wavelet basis functions. We will present a coordinate system called Nusselt coordinates which, when combined with wavelets, considerably simplifies computation of radiative transport and surface interaction. It also provides straightforward computation of the physical quantities involved. We show how to construct a discrete representation of the radiative transport operator involving inner products of smoothing functions, discuss the possible numerical integration techniques, and present an application. We also show how surface interaction can be represented as a kind of matrix product of the wavelet projections of an incident radiance and a bidirectional reflectance distribution function (BRDF).
Wavelet Encoding of BRDFs for RealTime Rendering
 In Graphics Interface 07
, 2007
"... Figure 1: An illuminated fabric with an acquired anisotropic velvet (left), isotropic wood (middle) and shiny plastic (right) BRDF rendered at 40 FPS (512 × 512) using our wavelet encoding. The initial data sets containing 32 4 RGB samples (12MB) are compressed into 3D textures of 700KB. Our approac ..."
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Cited by 3 (0 self)
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Figure 1: An illuminated fabric with an acquired anisotropic velvet (left), isotropic wood (middle) and shiny plastic (right) BRDF rendered at 40 FPS (512 × 512) using our wavelet encoding. The initial data sets containing 32 4 RGB samples (12MB) are compressed into 3D textures of 700KB. Our approach can be combined with classical texture, environment and bump mapping in order to produce high quality local illumination. Acquired data often provides the best knowledge of a material’s bidirectional reflectance distribution function (BRDF). Its integration into most realtime rendering systems requires both data compression and the implementation of the decompression and filtering stages on contemporary graphics processing units (GPUs). This paper improves the quality of realtime perpixel lighting on GPUs using a wavelet decomposition of acquired BRDFs. Threedimensional texture mapping with indexing allows us to efficiently compress the BRDF data by exploiting much of the coherency between hemispherical data. We apply builtin hardware filtering and pixel shader flexibility to perform filtering in the full 4D BRDF domain. Antialiasing of specular highlights is performed via a progressive levelofdetail technique built upon the multiresolution of the wavelet encoding. This technique increases rendering performance on distant surfaces while maintaining accurate appearance of close ones. CR Categories: I.3.7 [Computer Graphics]: ThreeDimensional Graphics and Realism—Color, shading, shadowing, and texture