130082 20240122171020.0 doi 10.1145/3450627 sideral 127194 ART-2021-127194 eng Crespo, M. Primary-space Adaptive Control Variates Using Piecewise-polynomial Approximations 2021 We present an unbiased numerical integration algorithm that handles both low-frequency regions and high-frequency details of multidimensional integrals. It combines quadrature and Monte Carlo integration by using a quadrature-based approximation as a control variate of the signal. We adaptively build the control variate constructed as a piecewise polynomial, which can be analytically integrated, and accurately reconstructs the low-frequency regions of the integrand. We then recover the high-frequency details missed by the control variate by using Monte Carlo integration of the residual. Our work leverages importance sampling techniques by working in primary space, allowing the combination of multiple mappings; this enables multiple importance sampling in quadrature-based integration. Our algorithm is generic and can be applied to any complex multidimensional integral. We demonstrate its effectiveness with four applications with low dimensionality: transmittance estimation in heterogeneous participating media, low-order scattering in homogeneous media, direct illumination computation, and rendering of distribution effects. Finally, we show how our technique is extensible to integrands of higher dimensionality by computing the control variate on Monte Carlo estimates of the high-dimensional signal, and accounting for such additional dimensionality on the residual as well. In all cases, we show accurate results and faster convergence compared to previous approaches. Access copy available to the general public Unrestricted info:eu-repo/grantAgreement/EC/H2020/682080/EU/Intuitive editing of visual appearance from real-world datasets/CHAMELEON This project has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No H2020 682080-CHAMELEON info:eu-repo/grantAgreement/ES/MINECO/PID2019-105004GB-I00 info:eu-repo/grantAgreement/ES/MINECO/TIN2016-78753-P info:eu-repo/semantics/openAccess All rights reserved http://www.europeana.eu/rights/rr-f/ 7.403 2021 COMPUTER SCIENCE, SOFTWARE ENGINEERING 9 / 110 = 0.082 2021 Q1 T1 7.148 2021 Computer Graphics and Computer-Aided Design 2021 Q1 14.2 2021 info:eu-repo/semantics/article info:eu-repo/semantics/acceptedVersion Jarabo, A. Universidad de Zaragoza (orcid)0000-0001-9000-0466 Muñoz, A. Universidad de Zaragoza (orcid)0000-0002-8160-7159 5007 570 Universidad de Zaragoza Dpto. Informát.Ingenie.Sistms. Área Lenguajes y Sistemas Inf. 40, 3 (2021), 25 [15 pp] ACM trans. graph. ACM TRANSACTIONS ON GRAPHICS 0730-0301 7217379 http://zaguan.unizar.es/record/130082/files/texto_completo.pdf Postprint 1805125 http://zaguan.unizar.es/record/130082/files/texto_completo.jpg?subformat=icon icon Postprint oai:zaguan.unizar.es:130082 articulos driver 2024-01-22-15:26:25 ARTICLE