Prototype-Based Low Altitude UAV Semantic Segmentation
Organizations: School of Artificial Intelligence, Optics and Electronics, Northwestern Polytechnical University · Institute of Artificial Intelligence (TeleAI), China Telecom
Abstract
Semantic segmentation of low-altitude UAV imagery presents unique challenges due to extreme scale variations, complex object boundaries, and limited computational resources on edge devices. Existing transformer-based segmentation methods achieve remarkable performance but incur high computational overhead, while lightweight approaches struggle to capture fine-grained details in high-resolution aerial scenes. To address these limitations, we propose PBSeg, an efficient prototype-based segmentation framework tailored for UAV applications. PBSeg introduces a novel prototype-based cross-attention (PBCA) that exploits feature redundancy to reduce computational complexity while maintaining segmentation quality. The framework incorporates an efficient multi-scale feature extraction module that combines deformable convolutions (DConv) with context-aware modulation (CAM) to capture both local details and global semantics. Experiments on two challenging UAV datasets demonstrate the effectiveness of the proposed approach. PBSeg achieves 71.86% mIoU on UAVid and 80.92% mIoU on UDD6, establishing competitive performance while maintaining computational efficiency. Code is available at https://github.com/zhangda1018/PBSeg.
Figures & tables
| Method | Per-Class IoU (%) | mIoU (%) | mF1 (%) | OA (%) | |||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Building | Road | Tree | LowVeg | MovingCar | StaticCar | Human | Clutter | ||||
| ABCNet [ 10 ] | 85.77 | 80.92 | 77.88 | 62.46 | 74.12 | 53.33 | 29.29 | 66.14 | 66.40 | 78.13 | 85.48 |
| BANet [ 18 ] | 83.90 | 81.48 | 78.51 | 62.18 | 77.44 | 52.01 | 29.51 | 64.58 | 66.00 | 77.86 | 84.99 |
| MANet [ 9 ] | 84.42 | 80.17 | 78.75 | 62.39 | 68.73 | 62.73 | 29.40 | 66.17 | 66.66 | 78.50 | 85.19 |
| DC-Swin [ 17 ] | 87.64 | 82.49 | 79.78 | 64.64 | 76.02 | 53.62 | 29.72 | 68.43 | 67.70 | 79.01 | 86.58 |
| GeoSeg [ 19 ] | 75.38 | 75.36 | 72.11 | 56.95 | 64.57 | 35.89 | 20.03 | 55.86 | 57.18 | 70.42 | 79.75 |
| Methods | Per-Class IoU (%) | mIoU (%) | mF1 (%) | OA (%) | |||||
|---|---|---|---|---|---|---|---|---|---|
| Façade | Road | Vegetation | Vehicle | Roof | Other | ||||
| ABCNet [ 10 ] | 73.10 | 70.05 | 89.79 | 71.64 | 88.68 | 63.27 | 78.65 | 87.76 | 88.13 |
| BANet [ 18 ] | 73.72 | 70.59 | 89.52 | 71.75 | 87.77 | 62.96 | 78.67 | 87.83 | 88.03 |
| MANet [ 9 ] | 72.53 | 68.84 | 89.49 | 70.37 | 87.64 | 62.58 | 77.78 | 87.22 | 87.58 |
| DC-Swin [ 17 ] | 75.50 | 73.03 | 89.72 | 72.08 | 89.14 | 64.95 | 79.89 | 88.61 | 88.95 |
| GeoSeg [ 19 ] | 55.87 | 58.40 | 87.16 | 48.16 | 76.08 | 50.20 | 65.13 | 78.00 | 80.39 |
| PBCA | CAM | DConv | UAVid | UDD6 | ||||
|---|---|---|---|---|---|---|---|---|
| mIoU | mF1 | OA | mIoU | mF1 | OA | |||
| ✗ | ✗ | ✗ | 66.84 | 78.52 | 85.31 | 77.15 | 86.48 | 86.92 |
| ✓ | ✗ | ✗ | 69.23 | 80.38 | 86.54 | 78.91 | 87.56 | 87.74 |
| ✗ | ✓ | ✗ | 68.15 | 79.47 | 85.89 | 77.82 | 86.95 | 87.28 |
| ✗ | ✗ | ✓ | 67.96 | 79.21 | 85.72 | 77.58 | 86.81 | 87.15 |
| ✓ | ✓ | ✗ | 70.45 | 81.28 | 87.35 | 79.74 | 88.11 | 88.42 |
| Method | FPS | GFLOPs | Latency (ms) | Para. (M) | mIoU | mF1 |
|---|---|---|---|---|---|---|
| ABCNet | 102.2 | 62.9 | 9.8 | 14.0 | 66.40 | 78.13 |
| BANet | 37.3 | 107.2 | 26.8 | 15.44 | 66.00 | 77.86 |
| MANet | 75.6 | 51.7 | 13.2 | 12.0 | 66.66 | 78.50 |
| DC-Swin | 23.5 | 170.3 | 42.6 | 45.6 | 67.70 | 79.01 |
| GeoSeg | 115.6 | 46.9 | 8.7 | 11.7 | 57.18 | 70.42 |
| CM-UNet | 47.7 | 83.8 | 21.0 | 8.7 | 59.45 | 72.24 |