This is a short paper which shows how the Lambertian case results can be applied to new methods of rendering diffuse objects with environment maps. The view and lighting above were not used at all in recovery, showing that the recovered BRDF under unknown illumination accurately predicts appearance for new views and lighting. Schematic of Reflection Figure 3. The frequency-space convolution formula Figure 4. Successive approximations to clamped cosine by adding more spherical harmonics.
Odd terms vanish, and even terms decay rapidly.
An illustration of our hybrid angular and frequency-space algorithm for estimating the lighting. The problem reduces to a simple 9x9 linear system. There is no explicit regularization and very high angular resolutions can be obtained. Also look at figure 1. Recovery of textured BRDFs under complex lighting.