Login | Register

Physics-based Learning of Photometric Invariance

Title:

Physics-based Learning of Photometric Invariance

Gevers, Maxime Lucienne (2025) Physics-based Learning of Photometric Invariance. Masters thesis, Concordia University.

[thumbnail of Gevers_MCompSc_F2025.pdf]
Text (application/pdf)
Gevers_MCompSc_F2025.pdf - Accepted Version
Restricted to Repository staff only until 1 March 2027.
Available under License Spectrum Terms of Access.
24MB

Abstract

Photometric invariance is vital in many computer vision tasks. Achieving robustness to photometric variations in imaging conditions requires the collection of accurate and sufficient ground-truth data for training. However, this task proves to be challenging, and as a result the reliance on synthetic data compromises the capacity of the model to adapt and generalize well to real-world situations. To address this issue, we move beyond purely data-driven paradigms by introducing physics priors as photometric invariants applicable across diverse models, datasets, and vision tasks. Specifically, we extend beyond task-specific physics priors and present a novel framework that systematically analyzes their effectiveness, thereby enabling a rigorous assessment of photometric-invariant physics priors across various vision tasks, such as semantic segmentation, intrinsic image decomposition (IID), color constancy, and image classification. We propose a physics-based self-supervised learning framework that extracts photometric-invariant features from unlabeled real-world images. Our approach integrates multiple physics priors and uncertainty modeling into a U-Net architecture, enabling robust, model-agnostic, and task-agnostic feature representations while facilitating efficient transfer learning under limited data regimes. Furthermore, we introduce IDTransformer, a transformer-based model incorporating photometric-invariant attention. In contrast to prior methods relying on hand-crafted priors or purely data-driven learning, IDTransformer captures reflectance transitions and clusters similar reflectance regions independently of spatial arrangement. By leveraging illumination- and geometry-invariant attention for reflectance mapping and geometry-variant attention for shading estimation, it achieves competitive performance with minimal training data.

Divisions:Concordia University > Gina Cody School of Engineering and Computer Science > Computer Science and Software Engineering
Item Type:Thesis (Masters)
Authors:Gevers, Maxime Lucienne
Institution:Concordia University
Degree Name:M. Sc.
Program:Computer Science
Date:12 September 2025
Thesis Supervisor(s):Poullis, Charalambos
ID Code:996401
Deposited By: Maxime Lucienne Gevers
Deposited On:04 Nov 2025 15:36
Last Modified:04 Nov 2025 15:36
All items in Spectrum are protected by copyright, with all rights reserved. The use of items is governed by Spectrum's terms of access.

Repository Staff Only: item control page

Downloads per month over past year

Research related to the current document (at the CORE website)
- Research related to the current document (at the CORE website)
Back to top Back to top