[Colloquium Cognitive Systems] Visual Perception of Materials and their Properties

Universität Ulm

Visual Perception of Materials and their Properties,

Prof. Dr. Roland Fleming (Uni Giessen),

19.07.2018 5:00 PM, Ulm University, 47.0.501

Abstract: Under typical viewing conditions, human observers effortlessly recognize materials and infer their physical, functional and multisensory properties at a glance. Without touching materials, we can usually tell what they would feel like, and we enjoy vivid visual intuitions about how they are likely to respond to external forces, allowing us to predict their behaviour as we interact with them. These achievements are impressive because the retinal image of a material results from extremely complex physical processes (e.g. sub-surface light transport; visco-elastic fluid flow). Due to their extreme diversity, mutability and complexity, materials represent a particularly challenging class of visual stimuli, so understanding how we recognize materials, estimate their properties, predict their behaviour, and interact with them could give us more general insights into visual processing and internal models of the physical world. What is ‘material appearance’, and how do we measure it and model it? How are material properties estimated and represented? Discussing these questions causes us to scrutinize the basic assumptions of ‘mid-level vision’ that prevail in theories of human vision, and gives hints at how to build a machine vision system that could learn materials from passive and active observations.