π€ AI Summary
This work addresses the challenges of high pixel-level annotation costs and the difficulty of unifying heterogeneous supervision signals in remote sensing change detection. The authors propose UniCD, a unified change detection framework that, for the first time, integrates supervised, weakly supervised, and unsupervised learning within a single collaborative architecture. By leveraging a shared encoder and a multi-branch mechanism, UniCD enables deep fusion of diverse supervision signals. Key innovations include a spatiotemporal awareness module (STAM), change representation regularization (CRR), and semantic priorβdriven change inference (SPCI), which collectively bridge the supervision gap. Experiments demonstrate that UniCD achieves state-of-the-art performance across all three settings, outperforming existing methods by 12.72% and 12.37% under weakly supervised and unsupervised protocols, respectively, on benchmark datasets such as LEVIR-CD.
π Abstract
Change detection (CD) aims to identify surface changes from multi-temporal remote sensing imagery. In real-world scenarios, Pixel-level change labels are expensive to acquire, and existing models struggle to adapt to scenarios with diverse annotation availability. To tackle this challenge, we propose a unified change detection framework (UniCD), which collaboratively handles supervised, weakly-supervised, and unsupervised tasks through a coupled architecture. UniCD eliminates architectural barriers through a shared encoder and multi-branch collaborative learning mechanism, achieving deep coupling of heterogeneous supervision signals. Specifically, UniCD consists of three supervision-specific branches. In the supervision branch, UniCD introduces the spatial-temporal awareness module (STAM), achieving efficient synergistic fusion of bi-temporal features. In the weakly-supervised branch, we construct change representation regularization (CRR), which steers model convergence from coarse-grained activations toward coherent and separable change modeling. In the unsupervised branch, we propose semantic prior-driven change inference (SPCI), which transforms unsupervised tasks into controlled weakly-supervised path optimization. Experiments on mainstream datasets demonstrate that UniCD achieves optimal performance across three tasks. It exhibits significant accuracy improvements in weakly and unsupervised scenarios, surpassing current state-of-the-art by 12.72% and 12.37% on LEVIR-CD, respectively.