Direct-to-indirect transfer for cinematic relighting

Hašan, Miloš; Pellacini, Fabio; Bala, Kavita

doi:10.1145/1141911.1141998

Cited by 73 publications

(85 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…First, many fast techniques for acquiring the light transport of real scenes have been proposed in recent literature [Debevec et al 2000;Masselus et al 2003;Peers et al 2006]. Precomputed light transport is popular even for synthetic rendering [Sloan et al 2002;Ng et al 2003;Hasan et al 2006]. In essence, these methods directly measure the effects of interreflections under various lighting conditions.…”

Section: Motivationmentioning

confidence: 99%

See 1 more Smart Citation

A Dual Theory of Inverse and Forward Light Transport

Bai

Chandraker

et al. 2010

Lecture Notes in Computer Science

View full text Add to dashboard Cite

A cornerstone of computer graphics is the solution of the rendering equation for interreflections, which allows the simulation of global illumination, given direct lighting or corresponding light source emissions. This paper lays the foundations for the inverse problem, whereby a dual theoretical framework is presented for inverting the rendering equation to undo interreflections in a real scene, thereby obtaining the direct lighting. Inverse light transport is of growing importance, enabling a variety of new applications like separation of individual bounces of the light transport, and projector radiometric compensation to display images free of global illumination artifacts in real-world environments that exhibit complex geometric and reflectance properties. However, solving the inverse problem involves the inversion of a large light transport matrix (acquired by measurement on real scenes). While straightforward matrix inversion is intractable for most realistic resolutions, there is scant prior work on either theoretical foundations or fast computational algorithms to meet the objectives of inverse light transport.In this paper, we develop a mathematical theory that exposes the duality of forward and inverse light transport. Forward rendering also formally involves a matrix or operator inversion, which is conceptually equivalent to a multi-bounce Neumann series expansion. We show the existence of an analogous series for the inverse problem. However, the convergence is oscillatory in the inverse case, with more interesting conditions on material reflectance. Importantly, we give physical meaning to this duality, by showing that each term of our inverse series cancels an interreflection bounce, just as the forward series adds them.In algorithmic terms, we develop the analog of iterative finite element methods like forward radiosity to efficiently solve light transport inversion. Our iterative inverse light transport algorithm is very fast, requiring only matrix-vector multiplications, and follows directly from the dual theoretical formulation. We also explore the connections to forward rendering in terms of Monte Carlo and wavelet-based techniques. As an initial practical application, we first acquire the light transport of a real static scene, and then demonstrate iterative inversion for radiometric compensation on high-resolution datasets, as well as rapid separation of the bounces of global illumination. *

show abstract

Section: Motivationmentioning

confidence: 99%

“…However, in our case, we do not see the light source or projector directly, but rather its effect on the scene or direct lighting (or equivalently "induced emission" l d ). Equation 1 is also the same formulation used in recent direct-to-indirect transfer methods for relighting of synthetic scenes [Hasan et al 2006]. …”

Section: Preliminariesmentioning

confidence: 99%

A Dual Theory of Inverse and Forward Light Transport

Bai

Chandraker

et al. 2010

Lecture Notes in Computer Science

View full text Add to dashboard Cite

show abstract

“…重光照技术一般有两种思路:把可选择的光照投影到基上以加速绘制,比如Dorsey [12,13] 和Dobashi [14] ;用图像的像素存储几何信息,比如Saito [15] 的几何帧缓存,之后几何帧缓存被扩展为深度帧缓存 [16,17] ,而Hasan [10] 将这类重光照的方法提高到实时的绘制速度.…”

Section: 离线的全局光照明算法有许多种:比如辐射度算法unclassified

Interactive Global Illumination Rendering with Spatial-Variant Dynamic Materials

Sun¹

2008

Journal of Software

View full text Add to dashboard Cite

This paper proposes a method of interactive global illumination rendering with spatial-variant dynamic materials under complex illumination. With the spatial-variant dynamic materials, the materials of the scene can be changed while rendering, and the changes to different parts of an object can be different. The non-linear relationship between materials and out-going radiance prevents users from changing the materials with most of existing interactive global illumination rendering algorithms. If different parts of an object are covered with different materials, the materials take much more complex effects on the out-going radiance. So there is still not an interactive global illumination rendering algorithm allow users to make different changes to different parts of an object. This paper approximates a region with spatial-variant dynamic materials by dividing it into numbers of sub-regions, the material in each sub-region is uniform and consistent. The radiance transferred in the scene may be reflected by different sub-regions successively, and the paper divides the out-going radiance according to different sequences of the reflection sub-regions. This paper also represents all materials with a linear basis, and applied the basis to all sub-regions to get all different distributions of the material basis. This paper precomputes all parts of radiance of all material basis distributions. In rendering process, it uses the materials' coefficients of basis to combine corresponding precomputed data to achieve the global illumination effects with interactive performance.

show abstract

“…In contrast, low-rank matrix approximations assume that high frequency projector lights are seldom present in the camera responses and acquire dense light transports from 3D target by using a system with custom optical apparatus [19]- [21]. For relighting with excellent presence that replicates real environments, we need to consider not only direct reflection light but also the global reflection light radiated from the entire environment because it yields key visual effects in real world scenes [8], [22], [23]. The former is caused by direct illumination from a point source, and the latter is caused by indirect illumination due to other points in a scene, e.g.…”

Section: Introductionmentioning

confidence: 99%

Dense Light Transport for Relighting Computation Using Orthogonal Illumination Based on Walsh-Hadamard Matrix

Miyagawa

Taniguchi

2016

IEICE Trans. Inf. & Syst.

View full text Add to dashboard Cite

SUMMARYWe propose a practical method that acquires dense light transports from unknown 3D objects by employing orthogonal illumination based on a Walsh-Hadamard matrix for relighting computation. We assume the presence of color crosstalk, which represents color mixing between projector pixels and camera pixels, and then describe the light transport matrix by using sets of the orthogonal illumination and the corresponding camera response. Our method handles not only direct reflection light but also global light radiated from the entire environment. Tests of the proposed method using real images show that orthogonal illumination is an effective way of acquiring accurate light transports from various 3D objects. We demonstrate a relighting test based on acquired light transports and confirm that our method outputs excellent relighting images that compare favorably with the actual images observed by the system.

show abstract

Direct-to-indirect transfer for cinematic relighting

Cited by 73 publications

References 38 publications

A Dual Theory of Inverse and Forward Light Transport

A Dual Theory of Inverse and Forward Light Transport

Interactive Global Illumination Rendering with Spatial-Variant Dynamic Materials

Dense Light Transport for Relighting Computation Using Orthogonal Illumination Based on Walsh-Hadamard Matrix

Contact Info

Product

Resources

About