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The piecewise smooth Mumford-Shah functional on an arbitrary graph
Leo Grady1, Christopher V Alvino
1Department of Imaging and Visualization, Siemens Corporate Research, Princeton, NJ 08540, USA.
Summary
This study reformulates the Mumford-Shah functional using graph-based combinatorial optimization. This novel approach yields faster, lower-energy image segmentation solutions compared to traditional gradient descent methods.
Area of Science:
- Computer Vision
- Image Analysis
- Computational Mathematics
Background:
- The Mumford-Shah functional is a cornerstone in image analysis for segmentation and filtering.
- Current optimization relies on active contours and gradient descent, prone to initialization issues and local minima.
Purpose of the Study:
- To reformulate the Mumford-Shah functional on arbitrary graphs.
- To apply combinatorial optimization techniques for improved efficiency and solution quality.
- To explore new applications beyond traditional image segmentation.
Main Methods:
- Reformulation of the Mumford-Shah functional on a graph structure.
- Application of combinatorial optimization algorithms.
- Comparison with gradient descent-based level set methods.
- Inclusion of regularization for image reconstruction outside boundaries.
Main Results:
- The graph formulation and combinatorial optimization achieve lower energy solutions.
- The new method significantly reduces computation time compared to gradient descent.
- Demonstrated effectiveness in new applications like point clustering and nonuniform image filtering.
Conclusions:
- Graph-based combinatorial optimization offers a superior alternative for Mumford-Shah functional minimization.
- This approach overcomes limitations of traditional gradient descent methods.
- The formulation enables broader applicability of the Mumford-Shah functional.
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