Fig. 1. Structure of YOLOv8s

Fig. 2. Improved structure of YOLOv8s

Fig. 3. LGSA structure

Fig. 4. Multi-Head Self-Attention workflow

Fig. 5. Structural diagram of backbone network improvements

Fig. 6. SCSA structure

Fig. 7. Structural diagram of neck network improvement

Fig. 8. Comparison of improved Soft-NMS detection

Fig. 9. Distribution of the number of vessels by type

Fig. 10. (a) Comparison of training processes for each model's mAP0.5; (b) Comparison of training processes for each model's mAP0.5∶0.95

Fig. 11. (a) YOLOv8s baseline model; (b) Improved YOLOv8s model

Fig. 12. (a) Original figure; (b) Improved YOLOv8s heat map; (c) YOLOv5s heat map; (d) YOLOv7 heat map; (e) YOLOv9 heat map; (f) YOLOv10 s heat map; (g) YOLOv11 heat map