Lightweight Multispectral Crop-Weed Segmentation for Precision Agriculture
Zeynep Galymzhankyzy, Eric Martinson
TL;DR
This work tackles robust crop–weed segmentation under diverse field conditions by introducing a lightweight transformer–CNN hybrid that processes RGB, NIR, and Red-Edge data through modality-specific encoders and a dynamic gated fusion mechanism. The approach achieves strong multispectral segmentation with 8.7 million parameters, yielding a mean IoU of $mIoU$ = 78.88% on the WeedsGalore dataset, substantially outperforming RGB-only baselines while maintaining real-time feasibility for UAV edge deployment. Compared with heavier baselines like DeepLabv3+ and MaskFormer, the model offers a favorable accuracy–efficiency trade-off suitable for site-specific weed management in precision agriculture. The work highlights the importance of adaptive modality weighting and multi-scale context, with future directions including domain adaptation, self-supervised pretraining, and hardware-aware optimization for field-scale deployment.
Abstract
Efficient crop-weed segmentation is critical for site-specific weed control in precision agriculture. Conventional CNN-based methods struggle to generalize and rely on RGB imagery, limiting performance under complex field conditions. To address these challenges, we propose a lightweight transformer-CNN hybrid. It processes RGB, Near-Infrared (NIR), and Red-Edge (RE) bands using specialized encoders and dynamic modality integration. Evaluated on the WeedsGalore dataset, the model achieves a segmentation accuracy (mean IoU) of 78.88%, outperforming RGB-only models by 15.8 percentage points. With only 8.7 million parameters, the model offers high accuracy, computational efficiency, and potential for real-time deployment on Unmanned Aerial Vehicles (UAVs) and edge devices, advancing precision weed management.
