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Discretization of parametrizable signal manifolds.
1Signal Processing Laboratory, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland. elif.vural@epfl.ch
This study introduces a new method for signal classification by approximating distances to transformation manifolds. Optimized manifold sampling improves classification accuracy, especially with asymmetric sample distribution.
Area of Science:
- Signal Processing
- Machine Learning
- Computer Vision
Background:
- Transformation-invariant analysis is crucial for signal classification.
- Estimating distances to transformation manifolds is computationally expensive.
- Approximating manifold distances using grids is a practical solution.
Purpose of the Study:
- Develop an efficient algorithm for selecting samples from transformation manifolds.
- Propose a method for joint discretization of multiple manifolds for improved classification.
- Optimize transformation-invariant classification accuracy.
Main Methods:
- Algorithm for selecting manifold samples to minimize distance estimation error.
- Joint optimization of multiple manifold discretizations.
- Asymmetric distribution of samples based on geometric structures.
Main Results:
- Individual manifold sampling minimizes distance estimation error, outperforming baselines in registration and classification.
- Joint optimization of samples further enhances classification performance.
- Asymmetric sample distribution can increase classification accuracy compared to equal distribution.
Conclusions:
- Optimized manifold sampling strategies significantly improve transformation-invariant signal classification.
- Joint optimization and asymmetric sample distribution are effective techniques for enhancing classification accuracy.
- The proposed methods offer a practical and efficient approach to manifold distance approximation for classification tasks.
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