Spectral Sensitivity Estimation with an Uncalibrated Diffraction Grating

TL;DR

This paper presents a practical calibration method for camera spectral sensitivity using an uncalibrated diffraction grating, eliminating the need for specialized filters or targets, and demonstrating superior accuracy in experiments.

Contribution

The proposed method estimates camera spectral sensitivity and diffraction parameters using only an uncalibrated diffraction grating, simplifying calibration procedures.

Findings

Outperforms traditional reference target-based calibration methods.

Works effectively on both synthetic and real-world data.

Provides a closed-form solution for calibration parameters.

Abstract

This paper introduces a practical and accurate calibration method for camera spectral sensitivity using a diffraction grating. Accurate calibration of camera spectral sensitivity is crucial for various computer vision tasks, including color correction, illumination estimation, and material analysis. Unlike existing approaches that require specialized narrow-band filters or reference targets with known spectral reflectances, our method only requires an uncalibrated diffraction grating sheet, readily available off-the-shelf. By capturing images of the direct illumination and its diffracted pattern through the grating sheet, our method estimates both the camera spectral sensitivity and the diffraction grating parameters in a closed-form manner. Experiments on synthetic and real-world data demonstrate that our method outperforms conventional reference target-based methods, underscoring its effectiveness and practicality.