Exploiting Boundary Loss for the Hierarchical Panoptic Segmentation of Plants and Leaves
Madeleine Darbyshire, Elizabeth Sklar, Simon Parsons
TL;DR
This work tackles the challenge of precision agriculture by developing a hierarchical panoptic segmentation framework that jointly identifies crops, weeds, and leaf instances while enabling leaf counting as a growth metric. It adapts Mask2Former with dual decoders (plants and leaves) and introduces focal loss and boundary loss, plus point sampling and deep supervision, to improve segmentation of small regions without increasing inference cost. On the PhenoBench UAV dataset, the approach achieves competitive panoptic quality (PQ) scores, with PQ$^{\dagger}$ reaching up to 83.70 using a SwinL backbone with test-time augmentation, and also yields improvements in leaf-count accuracy. The combination of lightweight architecture refinements and targeted loss functions demonstrates practical potential for real-world, data-efficient crop monitoring and targeted interventions in precision agriculture, with code available for reproducibility.
Abstract
Precision agriculture leverages data and machine learning so that farmers can monitor their crops and target interventions precisely. This enables the precision application of herbicide only to weeds, or the precision application of fertilizer only to undernourished crops, rather than to the entire field. The approach promises to maximize yields while minimizing resource use and harm to the surrounding environment. To this end, we propose a hierarchical panoptic segmentation method that simultaneously determines leaf count (as an identifier of plant growth)and locates weeds within an image. In particular, our approach aims to improve the segmentation of smaller instances like the leaves and weeds by incorporating focal loss and boundary loss. Not only does this result in competitive performance, achieving a PQ+ of 81.89 on the standard training set, but we also demonstrate we can improve leaf-counting accuracy with our method. The code is available at https://github.com/madeleinedarbyshire/HierarchicalMask2Former.
