论文标题
逆渲染的一般散射相函数
A General Scattering Phase Function for Inverse Rendering
论文作者
论文摘要
我们解决了在均质半透明材料中建模光散射并估算其散射参数的问题。散射相函数是影响散射辐射分布的这样的参数之一。它是在实践中建模的最复杂，最具挑战性的参数，通常使用经验相位函数。经验相功能（例如Henyey-Greenstein（HG）相位功能）通常会呈现，并限于特定的散射材料。这种限制引起了人们对目标材料通常未知的反向渲染问题的关注。在这种情况下，首选更通用的相位函数。尽管使用诸如Legendre多项式\ cite {Fowler1983}之类的基础中存在这种通用相位函数，但此相函数的逆渲染并不直接。这是因为基本多项式在某个地方可能是负的，而相位函数则不能。这项研究提出了一种新型的通用相位功能，可以避免此问题以及使用此阶段功能的逆渲染应用。用以MIE散射理论建模的广泛的材料对所提出的相函数进行了积极评估。通过模拟和现实世界实验评估了带有建议的相函数的散射参数估计。
We tackle the problem of modeling light scattering in homogeneous translucent material and estimating its scattering parameters. A scattering phase function is one of such parameters which affects the distribution of scattered radiation. It is the most complex and challenging parameter to be modeled in practice, and empirical phase functions are usually used. Empirical phase functions (such as Henyey-Greenstein (HG) phase function or its modified ones) are usually presented and limited to a specific range of scattering materials. This limitation raises concern for an inverse rendering problem where the target material is generally unknown. In such a situation, a more general phase function is preferred. Although there exists such a general phase function in the polynomial form using a basis such as Legendre polynomials \cite{Fowler1983}, inverse rendering with this phase function is not straightforward. This is because the base polynomials may be negative somewhere, while a phase function cannot. This research presents a novel general phase function that can avoid this issue and an inverse rendering application using this phase function. The proposed phase function was positively evaluated with a wide range of materials modeled with Mie scattering theory. The scattering parameters estimation with the proposed phase function was evaluated with simulation and real-world experiments.
