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Updated: Jul 7, 2026
07:56
A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
An optimal polygonal boundary encoding scheme in the rate distortion sense
G M Schuster1, A K Katsaggelos
1Adv. Technol. Res. Center, 3COM, Mount Prospect, IL 60056-2293, USA. gschuste@usr.com
Summary
This study introduces efficient lossy encoding methods for object boundaries using polygon approximation. It optimizes polygons for minimal distortion at a set bit rate or minimal bit rate for a set distortion.
Area of Science:
- Computer Vision
- Image Processing
- Data Compression
Background:
- Object boundary encoding is crucial for image and video compression.
- Existing methods for lossy boundary encoding can be computationally intensive or suboptimal.
Purpose of the Study:
- To develop fast and efficient methods for lossy encoding of object boundaries represented by chain codes.
- To address both minimizing distortion for a given bit rate and minimizing bit rate for a given distortion.
Main Methods:
- Boundary approximation using polygons.
- Development of a shortest path algorithm for distortion measures based on the maximum operator.
- Application of the Lagrange multiplier method combined with the shortest path algorithm for summation-based distortion measures.
- A tree-pruning algorithm to find all optimal solutions for the operational rate-distortion function.
Main Results:
- A fast and optimal scheme for the maximum operator distortion class.
- An effective approach for the summation operator distortion class using Lagrange multipliers and shortest path algorithms.
- Demonstration of the proposed methods on objects from the Miss America sequence.
Conclusions:
- The proposed methods provide efficient and effective solutions for lossy object boundary encoding.
- The algorithms offer flexibility in optimizing for distortion or bit rate.
- The techniques are validated with practical examples from video sequences.
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