MAPMaN: Multi-Stage U-Shaped Adaptive Pattern Matching Network for Semantic Segmentation of Remote Sensing Images

Abstract

Remote sensing images (RSIs) often possess obvious background noises, exhibit a multi-scale phenomenon, and are characterized by complex scenes with ground objects in diversely spatial distribution pattern, bringing challenges to the corresponding semantic segmentation. CNN-based methods can hardly address the diverse spatial distributions of ground objects, especially their compositional relationships, while Vision Transformers (ViTs) introduce background noises and have a quadratic time complexity due to dense global matrix multiplications. In this paper, we introduce Adaptive Pattern Matching (APM), a lightweight method for long-range adaptive weight aggregation. Our APM obtains a set of pixels belonging to the same spatial distribution pattern of each pixel, and calculates the adaptive weights according to their compositional relationships. In addition, we design a tiny U-shaped network using the APM as a module to address the large variance of scales of ground objects in RSIs. This network is embedded after each stage in a backbone network to establish a Multi-stage U-shaped Adaptive Pattern Matching Network (MAPMaN), for nested multi-scale modeling of ground objects towards semantic segmentation of RSIs. Experiments on three datasets demonstrate that our MAPMaN can outperform the state-of-the-art methods in common metrics. The code can be available at https://github.com/INiid/MAPMaN.