1B50 – Cognitive Vision
Daniel J Hulme
Outline
• Cognitive Vision– Why do we want Computers to See?– Why can’t Computers See?– Introducing Percepts and Concepts
• Visual System– The Eye and Brain– Early Visual Processes– Edge Detection
• Percepts and Concepts– Late Visual Processes– Concepts
What is Cognitive Science?
• Cognitive science is usually defined as the scientific study either of mind or of intelligence
• Intelligence is the mental capacity to reason, plan, solve problems, think abstractly, comprehend ideas and language, and learn
Brains
• Early creatures had very simple wiring
• Then came more complicated wiring
cnidariansBraitenberg's Vehicles
Cambrian ExplosionFemale Copilia
Compound-eye Trilobite
So what?
• Why do we want computers that can see?
• It seems that the evolution of the eye was a catalyst for the rapid development of the brain.
• Practical applications
• Philosophical implications
Why can’t computers see?
• The humble Bumblebee• 850,000 vs 100 billion neurons • 3D navigation, colour vision,
memory, communication, learning capacity, etc
• The brain of a bumblebee is a massively parallel processor with computation and storage capacities far superior to the most powerful supercomputer ever designed
Bumblebee
Why can’t computers see? (2)
• Ambiguity: perceiving one form from a potentially infinite amount of possible forms
• “We shall discuss violence on TV.”VP
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Gestalt
Semantics of Perception
• We don’t actually see what is ‘out there’!
• Distal – the 3D thing ‘out there’
• Proximal – 2D pattern of stimulus on retina
Semantics of Perception (2)
• We are bombarded by stimulus
• Passive and selective filtering
• Create a ‘useful’ perception– Early visual processes to extract features– Use experience to construct the scene
• Ontogenetic and Phylogenetic
– Use concepts to rationalise and decision make
Dimples
Maths
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Questions