2025Cum LaudeThesis

Advances in the Use of Fiducial Markers for Positioning Tasks with Cameras

Ph.D. Thesis · University of Córdoba

Computer VisionCum Laude

A page from the Large-Scale Indoor Camera Positioning chapter showing figures of the adjacent-rooms and corridor datasets

A dissertation page with body text and a results table

Appendix A: Glossary and Abbreviations, from the dissertation

Hand-sketched figure from the dissertation outlining the sparse camera setup, large-scale camera setup, fiducial object, and camera pose

Cover page of the dissertation, Advances in the Use of Fiducial Markers for Positioning Tasks with Cameras

Abstract

Camera pose estimation (determining a camera's spatial position and orientation with respect to a reference coordinate system) is fundamental to robotics, augmented reality, 3D reconstruction, and autonomous navigation. This dissertation advances the field through three key contributions, each tackling a different limitation of existing fiducial-marker-based methods.

It introduces fiducial objects (3D structures built from multiple markers) to improve accuracy and robustness in close-range, overlapping-view scenarios; a methodology for large-scale indoor camera positioning using reusable markers and graph-based optimization; and a novel approach for sparse camera configurations with non-overlapping fields of view, combining iterative marker placement with a mobile camera.

Together, these contributions offer scalable, versatile, and reliable solutions for camera pose estimation across a wide range of practical applications.

Contributions

Fiducial Objects3D structures composed of multiple custom-shaped markers, improving pose-estimation accuracy and robustness in close-range, overlapping-view scenarios.2× the pose-estimation precision of standard square markers, with up to 100% detection retained under heavy blur where standard markers drop to 73%.Large-Scale Indoor Camera PositioningA methodology for positioning large arrays of fixed indoor cameras using reusable fiducial markers and graph-based optimization.Sub-centimeter accuracy (0.46–0.63 cm) in synthetic tests, ≈15 cm across a real 214 m², 51-camera floor, reusing only 9 markers for the whole network.Sparse Camera PositioningAn approach for camera networks with non-overlapping fields of view, combining iterative marker placement with a mobile camera.Positioned 42 cameras with no shared views across a full two-story building at ≈42 cm accuracy, a scenario prior methods couldn't solve at all.

Directors

Rafael Muñoz-SalinasPh.D. · Thesis Director · University of Córdoba

Manuel J. Marín-JiménezPh.D. · Thesis Co-Director · University of Córdoba

Committee

Cristina Rubio Escudero (President)
Carlos García Martínez (Secretary)
Manuel Pegalajar Cuéllar (Vocal)

Citing

If you use this work in your research, please cite:

@phdthesis{garciaruiz2025fiducial,
  author  = {Garc\'{\i}a-Ruiz, Pablo},
  title   = {Advances in the Use of Fiducial Markers for Positioning Tasks with Cameras},
  school  = {Universidad de C\'{o}rdoba},
  year    = {2025},
  address = {C\'{o}rdoba, Spain},
  type    = {Doctoral dissertation},
  note    = {Advisors: Rafael Mu\~{n}oz-Salinas and Manuel J. Mar\'{\i}n-Jim\'{e}nez. Cum Laude},
  url     = {http://hdl.handle.net/10396/32915}
}

Dissertation

The full dissertation is openly available in the University of Córdoba's institutional repository.

View on Helvia (UCO Repository)

License

This dissertation is published Open Access under a CC BY-NC-ND 4.0 license.