  Road network extraction from satellite images is widely applicated in
intelligent traffic management and autonomous driving fields. The
high-resolution remote sensing images contain complex road areas and distracted
background, which make it a challenge for road extraction. In this study, we
present a stacked multitask network for end-to-end segmenting roads while
preserving connectivity correctness. In the network, a global-aware module is
introduced to enhance pixel-level road feature representation and eliminate
background distraction from overhead images; a road-direction-related
connectivity task is added to ensure that the network preserves the graph-level
relationships of the road segments. We also develop a stacked multihead
structure to jointly learn and effectively utilize the mutual information
between connectivity learning and segmentation learning. We evaluate the
performance of the proposed network on three public remote sensing datasets.
The experimental results demonstrate that the network outperforms the
state-of-the-art methods in terms of road segmentation accuracy and
connectivity maintenance.
