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arXiv · 2508.00330

Spectral Sensitivity Estimation with an Uncalibrated Diffraction Grating

Lilika Makabe·Hiroaki Santo·Fumio Okura·Michael S. Brown·Yasuyuki Matsushita
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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.

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Lilika Makabe, Hiroaki Santo, Fumio Okura, Michael S. Brown, Yasuyuki Matsushita. 2025-08-01. Spectral Sensitivity Estimation with an Uncalibrated Diffraction Grating. https://arxiv.org/abs/2508.00330

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