🤖 AI Summary
This study addresses the challenge of post-flood water body mapping under frequent missingness in multispectral imaging (MSI) data due to cloud cover or acquisition delays. To this end, we propose the Spatial Mask Adaptive Gating Network (SMAGNet), which leverages synthetic aperture radar (SAR) as the primary input and dynamically integrates partially or fully missing MSI data through an adaptive gating mechanism. Built upon a U-Net architecture, SMAGNet incorporates spatial masks and gating units to enable robust multimodal feature fusion. Evaluated on the C2S-MS Floods dataset, SMAGNet consistently outperforms existing methods across varying degrees of MSI missingness and achieves performance comparable to SAR-only models when MSI is entirely absent, thereby significantly enhancing mapping accuracy and model robustness in real-world disaster scenarios.