Efficient and Accurate Spherical Kernel Integrals Using Isotropic Decomposition
Efficient and Accurate Spherical Kernel Integrals Using Isotropic Decomposition
复制标题
使用各向同性分解的高效、准确的球形核积分
DOI：
10.1145/2797136
复制
发表时间：
2015
期刊：
影响因子：
--
通讯作者：
D. Nowrouzezahrai
中科院分区：
文献类型：
--
作者：
C. Soler;Mahdi M. Bagher;D. Nowrouzezahrai
球面滤波是图像合成中许多问题的基础，例如计算表面上的反射光或像素上的抗混叠镜面反射。该操作是具有挑战性的，因为球形滤波器的轮廓（例如，前面提到的视图评估的BRDF或几何扭曲的像素覆盖区）通常在每个像素处表现出空间和旋转变化，从而排除了预先计算的解决方案。我们使用各向同性球形分解（ISD）加速复杂的球形滤波任务，将球形滤波器分解为简单的各向同性内核的线性组合。我们的一般ISD是灵活的各向同性内核的选择，我们展示了ISD在渲染中的几个问题上的实际实现：着色和预过滤与空间变化的BRDF，抗锯齿环境映射的镜面反射，和噪声反射数据的过滤。与以前的基空间渲染解决方案相比，我们的着色解决方案以交互速率生成地面实况质量的结果，避免了昂贵的重建和大的近似误差。
Spherical filtering is fundamental to many problems in image synthesis, such as computing the reflected light over a surface or anti-aliasing mirror reflections over a pixel. This operation is challenging since the profile of spherical filters (e.g., the view-evaluated BRDF or the geometry-warped pixel footprint, mentioned before) typically exhibits both spatial and rotational variation at each pixel, precluding precomputed solutions. We accelerate complex spherical filtering tasks using isotropic spherical decomposition (ISD), decomposing spherical filters into a linear combination of simpler isotropic kernels. Our general ISD is flexible to the choice of the isotropic kernels, and we demonstrate practical realizations of ISD on several problems in rendering: shading and prefiltering with spatially varying BRDFs, anti-aliasing-environment-mapped mirror reflections, and filtering of noisy reflectance data. Compared to previous basis-space rendering solutions, our shading solution generates ground-truth-quality results at interactive rates, avoiding costly reconstruction and large approximation errors.