Type of Publication

Journal Articles

Date:

7 /

2007

Status

Published

DOI:

10.1117/1.2752493

Low-Cost Method for the Estimation of the Shape of Quadric Mirrors and Calibration of Catadioptric Cameras.

Featured in:

Journal of Optical Engineering, Society of Photo-Optical Instrumentation Engineers

Authors:

Nuno Goncalves and Helder Araújo

Abstract

This paper tackles the problem of quadric mirror estimation for omnidirectional imaging systems, as well as the poses of the camera relative to the mirror and to the world reference system. These estimates are obtained for quadric-shaped mirrors (including elliptic, parabolic, hyperbolic, and spherical mirrors) where the positions of the camera and mirror are unconstrained (fully noncentral configurations). The apparent contour of the mirror can be used to reduce the uncertainty in the estimation. Although it can enhance both the accuracy of the estimation (allowing the method to converge from farther initial configurations) and also its performance, its use is not strictly required. The intrinsic parameters of the camera model (pinhole or orthographic) are assumed to be known, as well as the structure of a calibration object in local coordinates. The method is nonlinear, and we use a genetic algorithm in conjunction with the Nelder-Mead simplex algorithm to minimize the objective function. Experimental results using real data are presented, demonstrating the accuracy of this calibration method, comparing its accuracy with and without the apparent contour, and computing its reprojection error. Because the mirror quadric is estimated, this method can also be used to identify and classify the mirror.

Citation
Nuno Goncalves and Helder Araújo. (2007). Low-cost method for the estimation of the shape of quadric mirrors and calibration of catadioptric cameras. Optical Engineering, 46(7), 073001-073001. DOI: 10.1117/1.2752493

Related Content

Researcher Coordinator, VIS TEAM Leader
No tagged content to show
No tagged content to show
No tagged content to show

RECENT PUBLICATIONS

VOIDFace: Towards an Effective Face Training Data Storage and Protection with Right to be Forgotten Property

Authors: Ajnas Muhammed; Iurii Medvedev; Nuno Gonçalves
Featured in: IEEE International Joint Conference on Biometrics (IJCB 2025)

Análise de marcadores biométricos e sinais vitais através de visão artificial: Ritmo Cardíaco

Authors: Rodrigo Rosado Gonçalves
Featured in: Bsc Thesis

How to Evaluate a Biometric Facial Image

Authors: Diana Gonçalves D’Amil
Featured in: Bsc Thesis

suggested news

Paper accepted to IJCB 2025
Prof. Nuno and VIS Team successfully organizes IbPRIA...
Four papers presented @ IbPRIA 2025

RECENT PROJECTS

FACING2 – Face Image Understanding
VISUAL-ID – Unique Visual Identities in Graphics, Images and Faces
UniqueMark

Institute of Systems and Robotics Department of Electrical and Computers Engineering University of Coimbra