Segmentation and Perceptual Grouping in Computer Vision
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Explore the concepts of segmentation, perceptual organization, and Gestalt principles in computer vision, including techniques like smooth completion, Hough transform, saliency networks, tensor voting, and stochastic completion fields.
Segmentation and Perceptual Grouping in Computer Vision
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Segmentation and Perceptual Grouping (Introduction to Computer Vision, 11.1.04) Kaniza
Perceptual Organization • Atomism, reductionism: • Perception is a process of decomposing an image into its parts. • The whole is equal to the sum of its parts. • Gestalt (Wertheimer, Köhler, Koffka 1912) • The whole is larger than the sum of its parts.
Proximity Gestalt Principles
Proximity Gestalt Principles • Proximity • Similarity
Proximity Similarity Gestalt Principles • Proximity • Similarity • Continuity
Closure Proximity Similarity Continuity Gestalt Principles
Proximity Similarity Continuity Closure Gestalt Principles • Closure • Common Fate
Proximity Similarity Continuity Gestalt Principles • Closure • Common Fate • Simplicity • Closure • Common Fate
Smooth Completion • Isotropic • Smoothness • Minimal curvature • Extensibility Elastica:
Elastica • Scale invariant (Weiss, Bruckstein & Netravali) • Approximation (Sharon, Brandt & Basri)
Saliency Network (Shashua & Ullman) Encourage • Length • Low curvature • Closure
Saliency Network (Shashua & Ullman)
Tensor Voting (Guy & Medioni) • Every edge element votes to all its circular edge completions • Vote attenuates with distance: e-αd • Vote attenuates with curvature: e-βk • Determine salience at every point using principal moments
Tensor Voting (Guy & Medioni)
Stochastic Completion Field (Mumford; Williams & Jacobs) • Random walk: • In addition, a particle may die with probability:
Stochastic Completion Fields (Mumford; Williams & Jacobs) • Most probable path: with
Stochastic Completion Fields (Mumford; Williams & Jacobs)
Stochastic Completion Fields (Mumford; Williams & Jacobs)
Stochastic Completion Fields (Mumford; Williams & Jacobs)
Shortest Path (Hu, Sakoda & Pavlidis)
Snakes (Kass, Witkin & Terzopolous) • Given a curve Г(s)=(x(s),y(s)), define:
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