CSNR and JMIM based spectral band selection for reducing metamerism in urban driving

Li, J., Shah, I. A., Geever, D., Collins, F., Ward, E., Glavin, M., et al. (2026). CSNR and JMIM Based Spectral Band Selection for Reducing Metamerism in Urban Driving. IEEE Open Journal of Intelligent Transportation Systems, 7, 1021-1033. https://doi.org/10.1109/OJITS.2026.3680774

Abstract

Protecting Vulnerable Road Users (VRU) remains a key challenge in automotive perception, particularly when RGB imagery exhibits metameric ambiguity under challenging illumination. Hyperspectral Imaging (HSI) can provide material-dependent cues beyond RGB, including in the Near-Infrared (NIR), but its high dimensionality limits deployment in automotive systems. This paper proposes a compact band-selection pipeline that combines joint mutual information maximization with a patch-based contrast signal-to-noise ratio criterion to select a practical 3-band HSI subset for VRU perception. On the Hyperspectral City V2 dataset, the proposed pipeline selects a VIS-NIR triplet at 521 nm, 753 nm, and 903 nm. We evaluate VRU-Road separability under higher-illumination scenes and an objectively defined low-illumination subset using per-scene distributions, and bootstrap confidence intervals. Results are reported in both a metric-ready representation (for direct comparison with co-registered RGB) and a sensor-native representation. Downstream utility is further evaluated by semantic segmentation using U-Net, DeepLabV3+, and PSPNet over three random seeds. The selected triplet improves VRU-Road separability on key criteria, remains robust under low illumination, and yields competitive downstream performance among the evaluated HSI-derived inputs. Overall, the proposed approach reduces spectral dimensionality from 128 bands to 3 (97.7% reduction) and supports compact multispectral sensing as a practical complement to RGB for robust VRU perception.

Funder

Taighde Éireann–Research Ireland
European Union

Publisher

Institute of Electrical and Electronics Engineers

Rights

CC BY

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