Overestimation and underestimation biases in photon mapping with non-constant kernels
dc.contributor.author
dc.date.accessioned
2015-12-04T09:30:23Z
dc.date.available
2015-12-04T09:30:23Z
dc.date.issued
2014-10-01
dc.identifier.issn
1077-2626
dc.identifier.uri
dc.description.abstract
This paper presents an analysis of the overestimation bias in common used filtering kernels in the context of photon mapping density estimation. We use the joint distribution of order statistics to calculate the expected value of the estimators of irradiance, and show that the estimator provided by the cone filter is not consistent unless the slope is one (yielding the triangular kernel), and that the Epanechnikov and Silverman kernels are consistent. The Gaussian filter has two different estimation biases: the original normalization constant α underestimates radiance by 46.9 percent, and the use of the th nearest photon reduces this underestimation slightly. We also show that a new normalization constant for the Gaussian filter together with discarding the contribution of the th nearest photon in the Gaussian and cone filter estimators produces new, consistent estimators. The specialized differential filter also benefits from the new estimate
dc.description.sponsorship
This work has been supported by the research projects coded TIN2010-21089-C03-01 and IPT-2011-0885-430000 (Spanish Commission for Science and Technology), by Grant 2009SGR643 (Catalan Government), and by FEDER funding from the European Union
dc.format.mimetype
application/pdf
dc.language.iso
eng
dc.publisher
Institute of Electrical and Electronics Engineers (IEEE)
dc.relation
info:eu-repo/grantAgreement/MICINN//TIN2010-21089-C03-01/ES/CONTENIDO DIGITAL PARA JUEGOS SERIOS: CREACION, GESTION, RENDERIZADO E INTERACCION/
AGAUR/2009-2014/2009 SGR-643
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Reproducció digital del document publicat a: http://dx.doi.org/10.1109/TVCG.2014.2314665
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© IEEE Transactions on Visualization and Computer Graphics, 2014, vol. 20, núm. 10, p. 1441-1450
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Articles publicats (D-IMA)
dc.rights
Tots els drets reservats
dc.subject
dc.title
Overestimation and underestimation biases in photon mapping with non-constant kernels
dc.type
info:eu-repo/semantics/article
dc.rights.accessRights
info:eu-repo/semantics/embargoedAccess
dc.embargo.terms
Cap
dc.date.embargoEndDate
info:eu-repo/date/embargoEnd/2026-01-01
dc.type.version
info:eu-repo/semantics/publishedVersion
dc.identifier.doi
dc.identifier.idgrec
022801
dc.contributor.funder
dc.relation.ProjectAcronym
dc.identifier.eissn
1941-0506