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A simple layered RGB BRDF model

Xavier Granier, Wolfgang Heidrich
2003 Graphical Models  
In this article, we introduce and experiment with a general approach to create similar and convincing effects, with a simple RGB BRDF model.  ...  We present a model for both specular and a diffuse reflection.  ...  He provides a lot of remarks and comments during the development of this model.  ... 
doi:10.1016/s1524-0703(03)00042-0 fatcat:l4uwj6zi6bg5hgol4jkmzrveeu

A simple layered RGB BRDF model

X. Granier, W. Heidrich
10th Pacific Conference on Computer Graphics and Applications, 2002. Proceedings.  
In this article, we introduce and experiment with a general approach to create similar and convincing effects, with a simple RGB BRDF model.  ...  We present a model for both specular and a diffuse reflection.  ...  He provides a lot of remarks and comments during the development of this model.  ... 
doi:10.1109/pccga.2002.1167836 dblp:conf/pg/GranierH02 fatcat:5zngx2dwv5emvi2qh3n6wyt6zu

BRDF Estimation of Complex Materials with Nested Learning [article]

Raquel Vidaurre, Dan Casas, Elena Garces, Jorge Lopez-Moreno
2018 arXiv   pre-print
We propose a novel method that predicts the model parameters of an artist-friendly, physically-based BRDF, from only two low-resolution shots of the material.  ...  The estimation of the optical properties of a material from RGB-images is an important but extremely ill-posed problem in Computer Graphics.  ...  Please note that the operations with RGB 0 , RGB 90 are not representing a simple multiplication of RGB channels, as the luminance is controlled by the Fresnel component.  ... 
arXiv:1811.09131v1 fatcat:4eiobhkydndrtnku5r7bzmc7ai

Generating Materials for Augmented Reality Applications using Natural Language

Sebastian Buntin
2016 Proceedings of the 7th Augmented Human International Conference 2016 on - AH '16  
In this paper, we present a novel method in parametrizing the BRDF (and other BxDF) as well as the texture map of a material by using natural language.  ...  The visual properties of a material can be described by the user using rather complex phrases in real time. These phrases then will be parsed and mapped to BRDF and texture parameters.  ...  material with a BRDF model (in their case [5] ).  ... 
doi:10.1145/2875194.2875195 dblp:conf/aughuman/Buntin16 fatcat:5i7hd6e2ibdi5d43o5be4xktde

A Lightweight Approach for On-the-Fly Reflectance Estimation [article]

Kihwan Kim, Jinwei Gu, Stephen Tyree, Pavlo Molchanov, Matthias Nießner, Jan Kautz
2018 arXiv   pre-print
Our method is learning-based, with an inference time of less than 90ms per scene and a model size of less than 340K bytes.  ...  In this paper, we propose a lightweight approach for surface reflectance estimation directly from 8-bit RGB images in real-time, which can be easily plugged into any 3D scanning-and-fusion system with  ...  Ward BRDF model [32] -due to two reasons: (1) the Ward BRDF model has a simple form but is representative for a wide variety of real-world materials [23] , and (2) prior studies [28, 34] on BRDF  ... 
arXiv:1705.07162v2 fatcat:qabf4f6pt5afniuluaklcpirwa

Material Modeling with Physical Constraints [article]

A. Weidlich, J. Meseth
2013 Eurographics Workshop on Material Appearance Modeling  
BRDFs.  ...  However, for predictive rendering other approaches are needed; for example, the usual approach to describe a material or a colour is to use RGB values for diffuse and specular.  ...  . • Layering Since only a limited number of materials can be described with a fix compound BRDF, we introduced a layer-based material model in our new rendering environment.  ... 
doi:10.2312/mam.mam2013.011-012 fatcat:fxut4ulrsvcipd36s3fjeyx24a

Towards Geometry Guided Neural Relighting with Flash Photography [article]

Di Qiu, Jin Zeng, Zhanghan Ke, Wenxiu Sun, Chengxi Yang
2020 arXiv   pre-print
We therefore propose a framework for image relighting from a single flash photograph with its corresponding depth map using deep learning.  ...  DecomposeNet: 3 copies of albedo, normal and roughness decoders DecomposeNet: albedo, normal and roughness estimation layers DecomposeNet: RGB encoder Layer K S Channels I O Input Channels rgb  ...  This BRDF model is controlled by a parameter called roughness, which is the subject of our prediction.  ... 
arXiv:2008.05157v1 fatcat:ds5egvgiirejvjz35wws3bxaa4

Reverse engineering approach to appearance-based design of metallic and pearlescent paints

Sergey Ershov, Roman Ďurikovič, Konstantin Kolchin, Karol Myszkowski
2004 The Visual Computer  
This approach includes solving the inverse problem, that is, finding pigment composition of a paint from its bidirectional reflectance distribution function (BRDF) based on a simple paint model.  ...  Such reverse engineering can serve as a starting point for subsequent design of new paints in terms of appearance attributes that are directly connected to the physical parameters of our model.  ...  We thank Alexander Letunov of the Keldysh Institute of Applied Mathematics (Moscow) for measuring the BRDF of paint samples.  ... 
doi:10.1007/s00371-004-0248-0 fatcat:hjzlqsa7s5ho7g77nkzxlmiaxi

Photo-realistic Rendering of Metallic Car Paint from Image-Based Measurements

Martin Rump, Gero Müller, Ralf Sarlette, Dirk Koch, Reinhard Klein
2008 Computer graphics forum (Print)  
Especially in sunlight these variations remain visible even for distances up to a few meters and give the coating a strong impression of depth which cannot be reproduced by a single BRDF model and the  ...  We use classical BRDF models like Cook-Torrance to represent the reflection behavior of the base paint and the highly specular finish and demonstrate how the parameters of these models can be derived from  ...  The directions ω i , ωo are calculated for every pixel x from the calibration data and the model is evaluated for that directions. Then a simple subtraction in RGB space is done.  ... 
doi:10.1111/j.1467-8659.2008.01150.x fatcat:jw5xqd3lvzcvlb5lifhw7zwf7a

Deep Photometric Stereo Networks for Determining Surface Normal and Reflectances

Hiroaki Santo, Masaki Samejima, Yusuke Sugano, Boxin Shi, Yasuyuki Matsushita
2020 IEEE Transactions on Pattern Analysis and Machine Intelligence  
To make the DPSN applicable to real-world scenes, a dataset of measured BRDFs (MERL BRDF dataset) has been used for training the network.  ...  Unlike previous photometric stereo methods that rely on a simplified parametric image formation model, such as the Lambert's model, the proposed method aims at establishing a flexible mapping between complex  ...  This work is licensed under a Creative Commons Attribution 4.0 License. For more information, see https://creativecommons.org/licenses/by/4.0/.  ... 
doi:10.1109/tpami.2020.3005219 pmid:32750795 fatcat:7wn7ttwmyfdafnuav3x4pdg73y

Metappearance: Meta-Learning for Visual Appearance Reproduction [article]

Michael Fischer, Tobias Ritschel
2022 arXiv   pre-print
We demonstrate this concept to be versatile and efficient, applying it to RGB textures, Bi-directional Reflectance Distribution Functions (BRDFs), or Spatially-varying BRDFs (svBRDFs).  ...  The second approach does not train a model that generalizes across the data, but overfits to a single instance of a problem, e.g., a flash image of a material.  ...  Finally, Sztrajman et al. [2021] show that a simple two-layer MLP can learn the mapping between angular measurements and RGB reflectance and is able to faithfully reproduce BRDFs. Architecture.  ... 
arXiv:2204.08993v1 fatcat:smqkgpmtpfcwzmodzbrlx3tz6u

Neural BRDFs: Representation and Operations [article]

Jiahui Fan and Beibei Wang and Miloš Hašan and Jian Yang and Ling-Qi Yan
2021 arXiv   pre-print
We propose a representation neural network to compress BRDFs into latent vectors, which is able to represent BRDFs accurately.  ...  Furthermore, our representation can be efficiently evaluated and sampled, providing a competitive solution to more expensive Monte Carlo layering approaches.  ...  Our sampling network is a simple four-layer MLP (with 128, 512, 128 and 32 hidden units individually).  ... 
arXiv:2111.03797v2 fatcat:umrb455fsneprig5ws2jpzj7jq

Neural apparent BRDF fields for multiview photometric stereo [article]

Meghna Asthana, William A. P. Smith, Patrik Huber
2022 arXiv   pre-print
on light source direction) allowing us to model the apparent BRDF.  ...  The appearance part of our neural representation is decomposed into a neural bidirectional reflectance function (BRDF), learnt as part of the fitting process, and a shadow prediction network (conditioned  ...  For the variant with fixed (Lambertian) BRDF, we replace the BRDF network with a single linear layer to map z to 3 values and use sigmoid activation to compute RGB diffuse albedo.  ... 
arXiv:2207.06793v1 fatcat:63be62lpo5gvlkqrw53tm5saym

Measurement and rendering of complex non-diffuse and goniochromatic packaging materials

Aditya Sole, Giuseppe Claudio Guarnera, Ivar Farup, Peter Nussbaum
2020 The Visual Computer  
models, to use for rendering.  ...  We demonstrate that in-plane retro-reflective measurements from a single input photograph, along with genetic algorithm-based BRDF fitting, allow to estimate an optimal set of parameters for reflectance  ...  (11) to estimate the sample BRDF. f r RGB (l, v) = k d RGB π + S RGB √ 1 − (n · h) F (θ h ) G (n · l, n · v) (n · l) (n · v) . (11) S RGB is the modified ABC distribution with parameter A (in S RGB  ... 
doi:10.1007/s00371-020-01980-9 fatcat:thqhangk6jclxcqaljdhcnza74

Reconstruction of Volumetric Surface Textures for Real-Time Rendering [article]

Sebastian Magda, David Kriegman
2006 Symposium on Rendering  
layers each representing a slice through the texture's volume.  ...  In this paper we propose a technique for generating a volumetric representation of a complex 3-D texture with unknown reflectance and structure.  ...  For a particular BRDF model with f parameters, we have to solve for n · u · v · ( f + 4) unknowns. For the trichromatic RGB model, the number of unknows is even greater.  ... 
doi:10.2312/egwr/egsr06/019-029 fatcat:moavcxjvyzapblmsky65j24xli
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