“…(1) Each surface point emits light rays ρ in each channel as a Gaussian over (r, g, b) with mean (µ r , µ g , µ b ) and variance (σ 2 r , σ 2 g , σ 2 b ) which means ρ = N (λ; µ c , σ 2 c ), c ∈ {r, g, b}, as similarly assumed by Oberlin and Tellex [21]. Under constant lighting condition we assume every point in the scene shares the same variance for the same color channel which means σ c = σ c , c ∈ {r, g, b} for all points in the scene.…”