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Estimation of shape of binary polygonal object from scattered field
1Department of Electrical and Computer Engineering, Indian Institute of Science, Bangalore 560012, India.
Summary
We developed a new method to determine the shape of weakly scattering binary objects using backscattered fields. This technique models scattered fields and uses illumination angles to accurately identify object corners and resolve ambiguities for multiple objects.
Area of Science:
- Optics and Photonics
- Computational Imaging
- Inverse Problems
Background:
- Estimating object shape from scattered fields is crucial in various scientific and engineering disciplines.
- Weakly scattering objects present challenges due to low signal-to-noise ratios.
- Previous methods often struggle with ambiguity, especially for complex or multiple objects.
Purpose of the Study:
- To present a novel method for estimating the shape of weakly scattering binary convex polygonal objects.
- To utilize the concept of scattering centers for accurate shape reconstruction.
- To resolve ambiguities in corner identification for single and multiple objects.
Main Methods:
- Modeling the backscattered field as a sum of complex sinusoids based on scattering centers.
- Employing three or more illumination directions, with at least two orthogonal.
- Analyzing the amplitude of the sinusoids to disambiguate corner joining.
Main Results:
- Successfully estimated the shape of weakly scattering binary convex polygonal objects.
- Identified all corners of an object using the proposed illumination strategy.
- Resolved ambiguity in joining corners for scenarios involving more than one object.
Conclusions:
- The presented method provides an effective approach for shape estimation of weakly scattering objects.
- The scattering center model and specific illumination strategy enable accurate corner detection.
- This technique offers a robust solution for disambiguating object configurations in complex scattering scenarios.
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