Spectral Upsampling Coefficient Tables - Jakob and Hanika. (2019)

<strong>Source URL</strong>: https://rgl.epfl.ch/publications/Jakob2019Spectral<br> <strong>Source DOI</strong>: 10.1111/cgf.13626 <strong>Abstract</strong> We present a versatile technique to convert textures with tristimulus colors into the spectral domain, allowing such content to be used in modern rendering systems. Our method is based on the observation that suitable reflectance spectra can be represented using a low-dimensional parametric model that is intrinsically smooth and energy-conserving, which leads to significant simplifications compared to prior work. The resulting spectral textures are compact and efficient: storage requirements are identical to standard RGB textures, and as few as six floating point instructions are required to evaluate them at any wavelength. Our model is the first spectral upsampling method to achieve zero error on the full sRGB gamut. The technique also supports large-gamut color spaces, and can be vectorized effectively for use in rendering systems that handle many wavelengths at once.<strong>来源链接</strong>：https://rgl.epfl.ch/publications/Jakob2019Spectral<br> <strong>来源数字对象标识符（DOI）</strong>：10.1111/cgf.13626 <strong>摘要</strong>：本文提出一种通用技术，可将带有三刺激色彩（tristimulus colors）的纹理转换至光谱域，使此类内容可应用于现代渲染系统。本方法基于如下观测：合适的反射光谱可通过低维参数模型表示，该模型本质上具备平滑性与能量守恒特性，相较先前研究可大幅简化流程。生成的光谱纹理兼具紧凑性与高效性：其存储需求与标准RGB纹理完全一致，且仅需6条浮点指令即可在任意波长下完成纹理求值。本模型是首个在完整sRGB色域上实现零误差的光谱上采样方法。该技术同时支持大色域色彩空间，且可高效向量化，适用于可同时处理多波长的渲染系统。