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Published on: March 6, 2013
Multi-Cue-Based Circle Detection and Its Application to Robust Extrinsic Calibration of RGB-D Cameras
Young Chan Kwon1, Jae Won Jang2, Youngbae Hwang3
1Department of Electronics Engineering, Incheon National University, Incheon 22012, Korea. yckwon@inu.ac.kr.
This study introduces a novel multi-cue method for detecting spherical objects in RGB-D camera images. This approach enhances the extrinsic calibration of multiple, sparsely distributed RGB-D cameras, improving accuracy with robust cost functions.
Area of Science:
- Computer Vision
- Robotics
- 3D Sensing
Background:
- Multiple RGB-Depth (RGB-D) cameras are crucial for 3D modeling and human-computer interaction.
- Sparse camera distribution without shared features presents challenges for extrinsic calibration.
- Spherical objects are valuable for calibrating widely-separated cameras due to their visibility from multiple viewpoints.
Purpose of the Study:
- To develop a robust method for detecting circular regions in single color images, specifically for identifying spherical objects.
- To apply this detection method to the extrinsic calibration of multiple RGB-D cameras.
- To improve calibration accuracy and robustness, especially in the presence of outliers and challenging environmental conditions.
Main Methods:
- A multi-cue-based algorithm for detecting circular regions in color images.
- Utilizing detected circular regions (spherical objects) for extrinsic camera calibration.
- Implementing robust cost functions to mitigate errors from misdetected sphere centers.
Main Results:
- The proposed circle detection method accurately identifies spherical objects in cluttered backgrounds and varying illumination.
- The extrinsic calibration method using robust cost functions demonstrates superior performance compared to least-squares methods.
- Accurate calibration results are achieved even with outliers, indicating enhanced robustness.
Conclusions:
- The developed multi-cue circle detection is effective for identifying spherical objects in challenging conditions.
- The proposed robust cost function approach significantly improves the extrinsic calibration of multiple RGB-D cameras.
- This method offers a more accurate and reliable solution for calibrating distributed camera systems.
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