Spectral sensitivity functions derived from brightness matching: implication of intensity invariance for color-vision...

Area of Science:

• Visual perception
• Photometry
• Color science

Background:

• Brightness sensitivity functions are crucial for understanding visual perception.
• Existing models often struggle to account for both superadditivity and subadditivity in brightness perception.
• Self-similarity in brightness perception has been hypothesized but not fully explored.

Purpose of the Study:

• To demonstrate the self-similarity of brightness sensitivity functions.
• To derive a structural restriction for sensitivity models based on this invariance.
• To validate a new brightness sensitivity model using this restriction.

Main Methods:

• Mathematical analysis of brightness sensitivity functions to establish self-similarity.
• Formulation of a new sensitivity model incorporating superadditivity and subadditivity.
• Simulations using direct brightness matching and magnitude estimation data.

Main Results:

• Brightness sensitivity functions were confirmed to be self-similar, unique up to a constant multiplier.
• A structural restriction for sensitivity models was derived from this invariance property.
• The new model demonstrated heuristic value in simulations across diverse datasets.

Conclusions:

• The self-similarity of brightness sensitivity functions offers a fundamental constraint for model development.
• The proposed model effectively accounts for both superadditivity and subadditivity.
• This invariance principle enhances the predictive power of brightness sensitivity models.