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A Closed-Form Solution to Single Scattering for General Phase Functions and Light Distributions

Vincent Pegoraro, Mathias Schott, Steven G. Parker
2010 Computer graphics forum (Print)  
As an alternative to traditional numerical estimation methods such as ray-marching and volume-slicing, a few analytical approaches to solving single scattering have been proposed but current techniques  ...  In this paper, we present the very first closed-form solution to the air-light integral in homogeneous media for general 1-D anisotropic phase functions and punctual light sources.  ...  Acknowledgements The authors wish to thank Thiago Ize and Abe Stephens for helpful discussions, Philipp Slusallek for allowing the ultimate stages of this work to be finalized after the first author joined  ... 
doi:10.1111/j.1467-8659.2010.01732.x fatcat:2dd5xxky45h6djmfjflevytyeq

An Analytical Solution to Single Scattering in Homogeneous Participating Media

Vincent Pegoraro, Steven G. Parker
2009 Computer graphics forum (Print)  
In this paper, we present a novel analytical approach to single scattering from isotropic point light sources in homogeneous media.  ...  We derive the first closed-form solution to the air-light integral in isotropic media and extend this formulation to anisotropic phase functions.  ...  Department of Energy through the Center for the Simulation of Accidental Fires and Explosions, under grant W-7405-ENG-48.  ... 
doi:10.1111/j.1467-8659.2009.01372.x fatcat:6tilrrafk5cqbnxhvxe5gzt344

Virtual ray lights for rendering scenes with participating media

Jan Novák, Derek Nowrouzezahrai, Carsten Dachsbacher, Wojciech Jarosz
2012 ACM Transactions on Graphics  
Abstract We present an efficient many-light algorithm for simulating indirect illumination in, and from, participating media.  ...  Our approach can compute the multiple scattering within the media in about a minute (middle-left), while in equal time, both the previous stateof-the-art approaches for general media (progressive photon  ...  We would like to thank Marios Papas, Ilya Baran, Steve Marschner, and Ladislav Kavan for feedback on an early draft of the paper; Benjamin Müller for initial investigations and experiments; and Krzysztof  ... 
doi:10.1145/2185520.2185556 fatcat:hm5hac6l5nazrh564ne7h2gqoq

Virtual ray lights for rendering scenes with participating media

Jan Novák, Derek Nowrouzezahrai, Carsten Dachsbacher, Wojciech Jarosz
2012 ACM Transactions on Graphics  
Abstract We present an efficient many-light algorithm for simulating indirect illumination in, and from, participating media.  ...  Our approach can compute the multiple scattering within the media in about a minute (middle-left), while in equal time, both the previous stateof-the-art approaches for general media (progressive photon  ...  We would like to thank Marios Papas, Ilya Baran, Steve Marschner, and Ladislav Kavan for feedback on an early draft of the paper; Benjamin Müller for initial investigations and experiments; and Krzysztof  ... 
doi:10.1145/2185520.2335411 fatcat:n7wtb3nhmrecnccraoywy7cduq

Simulation of multiple scattering in the systems with complicated phase function

E.V. Aksenova, D.I. Kokorin, V.P. Romanov
2015 Computer Physics Communications  
We consider simulation of multiple scattering of waves in isotropic and anisotropic media. The focus is on the construction of the phase function interpolation for the single scattering.  ...  For this system the grid corresponding to the adaptive partitioning is constructed and the transition to the diffusion regime for the photon distribution is presented.  ...  In turbid media, in many cases it is impossible to restrict ourselves to the single scattering of photons and it is necessary to take into account the multiple scattering.  ... 
doi:10.1016/j.cpc.2015.07.013 fatcat:rmzm3uxgv5g3vdg3kpmnl3svj4

Anisotropic reflectance from turbid media I Theory

Magnus Neuman, Per Edström
2010 Optical Society of America. Journal A: Optics, Image Science, and Vision  
This also means that a bulk scattering perfect diffusor does not exist. Angle-resolved models are thus crucial for a correct understanding of light scattering in turbid media.  ...  It is shown that the intensity of light reflected from plane-parallel turbid media is anisotropic in all situations encountered in practice.  ...  The upper bound of the error is 20-40% in a large area and increases asymptotically for thin media, while approaching zero only for thick highly scattering media (a).  ... 
doi:10.1364/josaa.27.001032 pmid:20448769 fatcat:qgsp4behm5ggzjhdjmpxvojgky

Crossed source–detector geometry for a novel spray diagnostic: Monte Carlo simulation and analytical results

Edouard Berrocal, Dmitry Y. Churmakov, Vadim P. Romanov, Mark C. Jermy, Igor V. Meglinski
2005 Applied Optics  
Monte Carlo calculations are then performed for typical parameters of sprays and aerosols with anisotropic (Mie) scattering in the intermediate single-to-multiple scattering regime.  ...  Sprays and other industrially relevant turbid media can be quantitatively characterized by light scattering.  ...  We are grateful to V. L. Kuzmin for valuable comments and discussions.  ... 
doi:10.1364/ao.44.002519 pmid:15881059 fatcat:mug5u4mgjvdd5pem4prghhez7a

Reflectance of Biological Turbid Tissues under Wide Area Illumination: Single Backward Scattering Approach

Guennadi Saiko, Alexandre Douplik
2014 International Journal of Photoenergy  
Various scenarios of light propagation paths in turbid media (single backward scattering, multiple backward scattering, banana shape) are discussed and their contributions to reflectance spectra are estimated  ...  Such a single backward scattering (SBS) approximation allows developing of an analytical approach which can take into account refractive index mismatched boundary conditions and multilayer geometry and  ...  Conclusions and Future Work Single backward scattering approximation allows developing an analytical approach which can take into account mismatched boundary conditions and multilayer geometry and can  ... 
doi:10.1155/2014/241364 fatcat:upe2gwh5zvd4vn2fhabjgduum4

Joint importance sampling of low-order volumetric scattering

Iliyan Georgiev, Jaroslav Křivánek, Toshiya Hachisuka, Derek Nowrouzezahrai, Wojciech Jarosz
2013 ACM Transactions on Graphics  
Isotropic Medium Anisotropic Medium (g = 0.9) 0-connection (Traditional PT) 3-connection (Ours) 0-connection (Traditional PT) 3-connection (Ours)  ...  We thank the anonymous reviewers for their suggestions on improving the paper, Jan Novák for pointing us to the related work in neutron transport, and Marios Papas and Tomáš Davidovič for running the heterogeneous  ...  This leads to a number of practical importance sampling routines to explicitly construct single-and double-scattering subpaths in anisotropically-scattering media.  ... 
doi:10.1145/2508363.2508411 fatcat:rcpso56ar5ettokm3dwptwjfzq

Exact solution of the characteristic equation for transfer in the anisotropically scattering and absorbing medium

Vladimir I. Haltrin
1988 Applied Optics  
A special form of anisotropic scattering phase function is shown to provide an exact solution of the characteristic equation for radiation transfer at depth within a scattering and absorbing medium.  ...  Exact solutions of the transfer equation play an important role in the study of the special features of light scattering in turbid media.  ...  in a scattering and absorbing medium easy to derive an expression for the second item in Eq. (14) by integrating the expansion of the generating function the azimuth mean phase function (14).  ... 
doi:10.1364/ao.27.000599 pmid:20523646 fatcat:bpkmxxk32rh53myutxcgzvwt44

Lateral light scattering in fibrous media

Tomas Linder, Torbjörn Löfqvist, Ludovic G. Coppel, Magnus Neuman, Per Edström
2013 Optics Express  
The inverse frequency at half maximum of the MTF is compared to both measurements and previous simulations with isotropic and strongly forward single scattering phase functions.  ...  It is found that the conical scattering by cylinders enhances the lateral scattering and therefore predicts a larger extent of lateral light scattering than models using rotationally invariant single scattering  ...  Anisotropic directional dependent scattering can for example be modelled by using phase functions derived from an analytical solution of electromagnetic scattering by an infinite cylinder [7] .  ... 
doi:10.1364/oe.21.007835 pmid:23546165 fatcat:q24oa6gp35gblkzg4qldzxopve

A survey on rendering homogeneous participating media

Wenshi Wu, Beibei Wang, Ling-Qi Yan
2021 Computational Visual Media  
Incoming light interacts with these participating media in complex ways: refraction at boundaries and scattering and absorption inside volumes.  ...  , accurate single scattering methods, neural network based methods, and spatially-correlated participating media related methods.  ...  [63] proposed an analytical solution for single scattering by participating media without boundaries under a point light, which can achieve a real-time frame rate.  ... 
doi:10.1007/s41095-021-0249-1 fatcat:vuvlmd5m7bg47gcpwmxq67nnlu

Role of Anisotropy and Refractive Index in Scattering and Whiteness Optimization

Gianni Jacucci, Jacopo Bertolotti, Silvia Vignolini
2019 Advanced Optical Materials  
In fact, despite the well-known analytical solution for the single scattering, [4, 22] the response of an ensemble of randomly arranged anisotropic particles has not been theoretically investigated.  ...  Light transport and scattering in a granular disordered medium are dictated by the spatial distribution (structure factor) and the scattering properties (form factor and refractive index) of its building  ...  An anisotropic S(q) translates into an anisotropic average distance between the scattering elements.  ... 
doi:10.1002/adom.201900980 fatcat:qokrrphdtzaavfita3lqofstsa

Real-Time Image-Based Volume Lighting [article]

Cyril Delalandre, Pascal Gautron, Jean-Eudes Marvie
2013 Eurographics State of the Art Reports  
The interaction of translucent objects with light creates complex effects such as scattering, absorption and volumetric shadows.  ...  While most accurate rendering approaches resort to heavy computations, recent needs in interactive applications have led to new types of algorithms, trading quality or genericity for speed.  ...  Figure 1 : 1 Figure 1: Our solution computes single scattering due to distant lighting using an optimized spherical harmonics projection of the scattered radiance.  ... 
doi:10.2312/conf/eg2013/short/057-060 fatcat:myep3jxjurfkzp4ovcctgn4r3m

Photon diffusion near the point-of-entry in anisotropically scattering turbid media

Edward Vitkin, Vladimir Turzhitsky, Le Qiu, Lianyu Guo, Irving Itzkan, Eugene B. Hanlon, Lev T. Perelman
2011 Nature Communications  
From astronomy to cell biology, the manner in which light propagates in turbid media has been of central importance for many decades.  ...  Our theory properly treats anisotropic photon scattering events and takes the specifi c form of the phase function into account.  ...  R33 RR017361 and in part by the Department of Veterans Aff airs, Offi ce of Research and Development.  ... 
doi:10.1038/ncomms1599 pmid:22158442 pmcid:PMC3370954 fatcat:hy5wrsfryzhe3h3hasgdwmgwem
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