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Image-driven Navigation of Analytical BRDF Models [article]

Addy Ngan, Frédo Durand, Wojciech Matusik
2006 Symposium on Rendering  
Next, we propose a user interface that allows for navigation in the remapped parameter space of a given BRDF model.  ...  Specifying parameters of analytic BRDF models is a difficult task as these parameters are often not intuitive for artists and their effect on appearance can be non-uniform.  ...  Next, we create an interface where the user navigates within a BRDF model with parameters remapped using our metric.  ... 
doi:10.2312/egwr/egsr06/399-407 fatcat:6jrfvcohv5cdjjjmwpvnhivbqu

Experimental validation of analytical BRDF models

Addy Ngan, Frédo Durand, Wojciech Matusik
2004 ACM SIGGRAPH 2004 Sketches on - SIGGRAPH '04  
A variety of analytical models have been proposed to represent BRDFs. However, validation of these models have been scarce due to the lack of high resolution measured data.  ...  The differences between the BRDF fits are also perceptually significant in rendered images.  ... 
doi:10.1145/1186223.1186336 dblp:conf/siggraph/NganDM04 fatcat:4o4h4hate5hqnogq3pcwqa46im

A Composite BRDF Model for Hazy Gloss

P. Barla, R. Pacanowski, P. Vangorp
2018 Computer graphics forum (Print)  
Our main contribution then consists in a mapping from perceptual to physical parameters that ensures the resulting composite BRDF is valid in terms of reciprocity, positivity and energy conservation.  ...  We propose relying on a composite material based on a pair of arbitrary BRDF models; however, instead of controlling their physical parameters, we expose perceptual parameters inspired by visual experiments  ...  ., Ashikhmin-Shirley [AS00]), their parameter should be remapped to α.  ... 
doi:10.1111/cgf.13475 fatcat:i6me76iae5ce7ie72rqh5zcuk4

Attribute-preserving gamut mapping of measured BRDFs

Tiancheng Sun, Ana Serrano, Diego Gutierrez, Belen Masia
2017 Computer graphics forum (Print)  
From such intermediate representation, we then perform an image-based optimization including color information, to bring the BRDF into gamut.  ...  We present a novel two-step gamut mapping algorithm that allows users to specify which perceptual attribute of the original material they want to preserve (such as brightness, or roughness).  ...  [VLD07, FDA03] , but directly changing the parameters of analytical models usually results in unintuitive and perceptually non-uniform changes as well.  ... 
doi:10.1111/cgf.13223 fatcat:5lt72jqmurfdnamcejwrvzemmm

Experimental Analysis of BRDF Models [article]

Addy Ngan, Frédo Durand, Wojciech Matusik
2005 Symposium on Rendering  
In this work we evaluate several well-known analytical models in terms of their ability to fit measured BRDFs.  ...  A variety of analytical models have been proposed to represent BRDFs. However, analysis of these models has been scarce due to the lack of high-resolution measured data.  ...  number of parameters for the specular lobe: M = (dr, dg, d b )di f f use+(sr, sg, s b )specular(p 0 , p 1 , ..., pn) Fitting BRDFs A core part of our analysis is to fit measured BRDFs to analytical  ... 
doi:10.2312/egwr/egsr05/117-126 fatcat:mj6h5rcurnah7jnqe5vebfzchm

On cross-validation and resampling of BRDF data measurements

Vlastimil Havran, Attila Neumann, Georg Zotti, Werner Purgathofer, Hans-Peter Seidel
2005 Proceedings of the 21st spring conference on Computer graphics - SCCG '05  
Further, we show how the perceptually uniform color space CIE 1976 L * a * b * is used for crosscomparison of BRDF data measurements, which were not calibrated.  ...  Abstract We discuss the validation of BTF data measurements by means used for BRDF measurements. First, we show how to apply the Helmholtz reciprocity and isotropy for a single data set.  ...  The proposed method can also be used to validate analytical BRDF models against measured BRDF data.  ... 
doi:10.1145/1090122.1090149 dblp:conf/sccg/HavranNZPS05 fatcat:pai6qeh5nnfwhgnbdopds2voca

Three Perceptual Dimensions for Specular and Diffuse Reflection

Matteo Toscani, Dar'ya Guarnera, Giuseppe Claudio Guarnera, Jon Yngve Hardeberg, Karl R. Gegenfurtner
2020 ACM Transactions on Applied Perception  
Previous research investigated the perceptual dimensionality of achromatic reflection of opaque surfaces, by using either simple analytic models of reflection, or measured reflection properties of a limited  ...  Alternative approaches use measured BRDF data, for instance from existing datasets such as MERL [64] , UTIA [27] and RGL [23], to convert BRDFs into products of compact non-parametric lower-dimensional  ...  In order to place our stimuli in the BRDF space in which contrast gloss and DOI gloss are defined, we used a BRDF parameter remapping technique [38, 39] to determine the optimal set of Ward-model's parameters  ... 
doi:10.1145/3380741 fatcat:oh34xpn2frc4bgcy2cjs5ippbe

BxDF material acquisition, representation, and rendering for VR and design

Giuseppe Claudio Guarnera, Dar'ya Guarnera, Gregory J. Ward, Mashhuda Glencross, Ian Hall
2019 SIGGRAPH Asia 2019 Courses on - SA '19  
(c) Example of BRDF parameter remapping [Guarnera et al. 2019] : source models (on the left), remapped appearance (at the center), error map (on the right).  ...  Their pipeline, aimed at providing a perceptually accurate remapping also for anisotropic BRDFs and SVBRDFs, relies on a metric in image space which exploits features to which the human visual system is  ...  BRDF PARAMETER REMAPPING TECHNIQUES The need to manually match the appearance of a material in two or more diferent rendering tools is common in digital 3D product design, due to the wide range of tools  ... 
doi:10.1145/3355047.3362092 dblp:conf/siggrapha/GuarneraGWGH19 fatcat:svhceicugfaevjb27duxfiai4i

Displacement interpolation using Lagrangian mass transport

Nicolas Bonneel, Michiel van de Panne, Sylvain Paris, Wolfgang Heidrich
2011 Proceedings of the 2011 SIGGRAPH Asia Conference on - SA '11  
Since we used a parametric BRDF model, we can compute the ground-truth in-between BRDF by interpolating the parameters (e).  ...  Working with a flattened BRDF representation in a Euclidean space produces large conspicuous errors (d).  ...  Validation and Experiments We test our method with a parametric BRDF model so that we can render reference images by interpolating the model parameters.  ... 
doi:10.1145/2024156.2024192 fatcat:vucyhbadmrelfduzzbpqfp4qla

Displacement interpolation using Lagrangian mass transport

Nicolas Bonneel, Michiel van de Panne, Sylvain Paris, Wolfgang Heidrich
2011 ACM Transactions on Graphics  
Since we used a parametric BRDF model, we can compute the ground-truth in-between BRDF by interpolating the parameters (e).  ...  Working with a flattened BRDF representation in a Euclidean space produces large conspicuous errors (d).  ...  Validation and Experiments We test our method with a parametric BRDF model so that we can render reference images by interpolating the model parameters.  ... 
doi:10.1145/2070781.2024192 fatcat:uzfdqizwlbfqvlrobmhe24wnmm

Displacement interpolation using Lagrangian mass transport

Nicolas Bonneel, Michiel van de Panne, Sylvain Paris, Wolfgang Heidrich
2011 Proceedings of the 2011 SIGGRAPH Asia Conference on - SA '11  
Since we used a parametric BRDF model, we can compute the ground-truth in-between BRDF by interpolating the parameters (e).  ...  Working with a flattened BRDF representation in a Euclidean space produces large conspicuous errors (d).  ...  Validation and Experiments We test our method with a parametric BRDF model so that we can render reference images by interpolating the model parameters.  ... 
doi:10.1145/2070752.2024192 fatcat:xv7avoqf5jehrnd46ghhdgvway

Painterly depiction of material properties

Mitchell J. P. van Zuijlen, Sylvia C. Pont, Maarten W. A. Wijntjes
2020 Journal of Vision  
Participants made perceptual judgments about 30 unique segments of these materials for 10 material attributes, such as glossiness, roughness, hardness, etc.  ...  The probe can be parameterized by an analytical physical model (e.g., Ward), weight parameters of data-driven Bidirectional Reflectance Distribution Functions (BRDFs) (Matusik, Pfister, Brand, & McMillan  ...  They mapped these perceptual attributes to an underlying principal component analysis (PCA)-based representation of BRDFs (i.e., physical parameters) and showed that their functionals were good predictors  ... 
doi:10.1167/jov.20.7.7 pmid:32634227 pmcid:PMC7426625 fatcat:jmornjo3kbdi7cla4pyypi473q

Reciprocal shading for mixed reality

Martin Knecht, Christoph Traxler, Oliver Mattausch, Michael Wimmer
2012 Computers & graphics  
Therefore, in most computer graphics applications analytical models [105, 14, 102] are used instead of measured BRDFs to these days.  ...  In its most simple form the BRDF takes an incoming (ω i ) and outgoing (ω o ) light direction as parameters.  ... 
doi:10.1016/j.cag.2012.04.013 fatcat:z5owq3q6xnhxbjrr7tzrpn6t7u

Augmenting physical avatars using projector-based illumination

Amit Bermano, Philipp Brüschweiler, Anselm Grundhöfer, Daisuke Iwai, Bernd Bickel, Markus Gross
2013 ACM Transactions on Graphics  
Based on this data, the actuation parameters of the head are remapped to match the dynamics of the target performance.  ...  Applying the proposed approach reduces the artifacts below a perceptual level (c).  ... 
doi:10.1145/2508363.2508416 fatcat:grj6yuft5rdxhbuwwcmsfm2r4q

Scattering-aware texture reproduction for 3D printing

Oskar Elek, Denis Sumin, Ran Zhang, Tim Weyrich, Karol Myszkowski, Bernd Bickel, Alexander Wilkie, Jaroslav Křivánek
2017 ACM Transactions on Graphics  
Our method employs an e cient numerical optimizer on top of a general Monte-Carlo simulation of heterogeneous scattering, supported by a practical calibration procedure to obtain scattering parameters  ...  Validation of our optimization.  ...  Perceptual Considerations.  ... 
doi:10.1145/3130800.3130890 fatcat:m5o53pr2sbebhea6fvsxaedjbm
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