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.
翻译:我们处理在同质半透明材料中模拟光散射并估计其散射参数的问题。 散射阶段功能是影响散射辐射分布的参数之一。 这是实践中最复杂和最具挑战性的参数, 通常使用经验阶段函数。 经验阶段函数( 如Henyey- Greenstein(HG) 阶段函数或经修改的函数) 通常呈现并限于特定范围的散射材料。 这一限制引起对目标材料一般未知的反向偏移问题的关注。 在这种情况下, 偏好采用更一般的阶段函数。 虽然在多面形中存在这种一般性的阶段函数, 其基础是Tultorre 聚光年/ cite{Fowler1983}, 与这一阶段函数反向转换并非直截的。 这是因为基础的多面级函数通常在某个特定范围的地方呈负值, 而一个阶段函数则无法。 这项研究提出了一个新的一般阶段功能, 避免这一问题, 并用这个阶段函数反向应用。 拟议的阶段函数是用一个积极的评估, 与模拟的模型和模拟模型进行了模拟, 模拟, 与模拟。