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Published on: August 30, 2012
Detecting motion through dynamic refraction
Marina Alterman1, Yoav Y Schechner, Pietro Perona
1Department of Electrical Engineering, Technion-Israel Institute of Technology, Haif a32000, Israel. amarina@tx.technion.ac.il
IEEE Transactions on Pattern Analysis and Machine Intelligence
|November 17, 2012
Summary
This study presents a simple method to detect moving objects through strong, random distortions caused by atmospheric turbulence or water surfaces. The technique effectively identifies object motion without needing to fully recover the distorted scene.
Area of Science:
- Optics and Photonics
- Computer Vision
- Robotics
Background:
- Refraction creates dynamic distortions in atmospheric and underwater viewing conditions.
- Submerged animals and humans (e.g., divers, submarines) face challenges detecting objects through these distortions.
- Complete scene recovery from dynamic refractions is computationally difficult.
Purpose of the Study:
- To develop a method for detecting moving objects despite strong, random refractive distortions.
- To avoid the complex task of full scene recovery when only object motion is of interest.
- To enable detection of moving objects even with zero mean motion.
Main Methods:
- Utilizing a simple motion feature to discriminate moving object points from background.
- Leveraging the mutual independence between object motion and distortion.
- Focusing on detecting motion rather than inverting distortions.
Main Results:
- Moving objects can be detected with high accuracy and low false-positive rates.
- The method is effective even when distortions are severe and dominate object motion.
- Detection is successful even for objects with zero mean motion.
Conclusions:
- A straightforward motion-based feature allows for robust detection of moving objects through refractive distortions.
- This approach simplifies the problem by focusing solely on motion detection, bypassing full scene restoration.
- The findings have implications for underwater surveillance, robotics, and augmented reality systems.
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