Human Perception 9: Color.

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Presentation transcript:

Human Perception 9: Color

Color Appearance and Context

Color Matching and Context

Color Signaling Pathway

Surface Reflectance Functions

Illumination Effect on Absorptions

Why are Linear Models Useful? Compact representation of the data Work smoothly with conventional linear matrix computations Help understand practical matters like the number of sensors needed to measure a set of signals

Example Daylights

Daylight Basis Functions (CIE)

Macbeth Chart: Reflectance

Macbeth Chart Basis Functions

Macbeth Approximations: Functions

Macbeth Approximations: Appearance

Illumination(3) and Reflectance(3) Yellow illuminant Blue illuminant Black surface Not used in the paper, but a good introductory point for talks. White surface

Surface & Illuminant Estimation Gray world assumption Average of all the surfaces in the image is gray Uniform perfect reflector The brightest surface in the image Specularities Glossy surface reflects the illumination directly

Color Signaling Pathway

Example Daylights

Macbeth Chart Basis Functions

The Photoreceptor Types Cone wavelength absorptions