NCSS-Net: A Negatively Constrained Network with Self-Supervised Band Selection for Hyperspectral Image Underwater Target Detection

Detecting nearshore underwater targets in hyperspectral imagery faces significant challenges due to complex background clutter, weak and distorted underwater target signals. Extracting discriminative features is a critical step. Current methods are often constrained by high spectral redundancy and reliance on manual annotations, leading to suboptimal detection performance. To address these problems, this paper proposes a novel underwater target detection framework that integrates self-supervised band selection with a physically-constrained detection, called the negatively constrained network with self-supervised band selection (NCSS-Net). Specifically, NCSS-Net first generates a target-prior abundance map via Normalized Difference Water Index and spectral unmixing. This abundance map is then converted into a binary target mask through adaptive thresholding. The binary target mask serves as pseudo labels and guides an Artificial Bee Colony algorithm to identify a maximally discriminative band subset. These bands are then fed into a negatively-constrained autoencoder. This network is trained with a specialized loss function to enforce negative correlation between the target and water endmembers, thereby enhancing their separability. Experimental results demonstrate that NCSS-Net outperforms existing state-of-the-art methods, offering an effective and practical solution for nearshore underwater monitoring applications. Our code will be available online upon acceptance.