Dual Stream Segmentation Network for Real-Time Semantic Segmentation

Modern real-time segmentation methods employ two-branch framework to achieve good speed and accuracy trade-off. However, we observe that low-level features coming from the shallow layers go through less processing, producing a potential semantic gap between different levels of features. Meanwhile, a rigid fusion is less effective due to the absence of consideration for two-branch framework characteristics. In this paper, we propose two novel modules: Unified Interplay Module and Separate Pyramid Pooling Module to address those two issues respectively. Based on our proposed modules, we present a novel Dual Stream Segmentation Network (DSSNet), a two-branch framework for real-time semantic segmentation. Compared with BiSeNet, our DSSNet based on ResNet18 achieves better performance 76.45% mIoU on the Cityscapes test dataset while sharing similar computation costs with BiSeNet. Furthermore, our DSSNet with ResNet34 backbone outperforms previous real-time models, achieving 78.5% mIoU on the Cityscapes test dataset with speed of 39 FPS on GTX1080Ti.