Synthetic Thermal Image Generation for Real-Time Animal Detection Under Low-Visibility Conditions
Organizations: The Beacom College of Computer and Cyber Sciences, Dakota State University
Abstract
Wildlife-vehicle collisions remain a significant road safety concern, particularly during nighttime and low-visibility conditions when RGB-based perception systems are often unreliable. Thermal imaging offers a promising alternative for detecting animals under poor illumination. However, the limited availability of annotated infrared animal datasets restricts the development of robust deep learning-based detection models. This paper investigates synthetic thermal image generation as a scalable approach for real-time animal detection under low-visibility conditions. A subset of 514 annotated visible-spectrum animal images from the NTLNP dataset is translated into synthetic thermal representations using CycleGAN-Turbo, while a limited real thermal dataset of 60 images is expanded through thermal-focused augmentation. Multiple object detection architectures, including YOLOv8, YOLOv9, YOLOv10, and RT-DETR, are trained independently on synthetic and real thermal datasets and evaluated using precision, recall, [email protected], [email protected]:0.95, model size, and inference latency. Experimental results show that synthetic thermal images provide competitive detection performance, with RT-DETR achieving the highest synthetic-data [email protected] of 0.9613. Models trained on augmented real thermal data achieve the strongest overall performance, with YOLOv10s obtaining 0.9879 [email protected] and 0.9571 [email protected]:0.95. Computational analysis further indicates that lightweight YOLO variants provide favorable inference latency, supporting their potential for real-time deployment. These findings demonstrate that synthetic thermal imagery can reduce dependence on scarce infrared datasets and support the development of efficient animal detection systems for future vehicle-mounted wildlife collision mitigation applications.
Figures & tables
| Model | Dataset | Precision | Recall | ||
| YOLOv8n | Synthetic | 0.9318 | 0.6788 | 0.7857 | 0.9662 |
| YOLOv8n | Real Thermal | 0.9827 | 0.9493 | 0.8384 | 0.9140 |
| YOLOv8s | Synthetic | 0.8837 | 0.6821 | 0.8922 | 0.8263 |
| YOLOv8s | Real Thermal | 0.9874 | 0.9527 | 0.9374 | 0.9120 |
| YOLOv9t | Synthetic | 0.8683 | 0.6596 | 0.9070 | 0.8658 |
| YOLOv9t | Real Thermal | 0.9831 | 0.9483 | 0.8890 | 0.8876 |
| Model | Parameters (M) | Latency (ms) | GFLOPs |
| YOLOv8n | 3.0 | 8.37–14.07 | 8.1 |
| YOLOv8s | 11.1 | 8.58–14.25 | 28.4 |
| YOLOv9t | 2.0 | 14.44–20.25 | 7.6 |
| YOLOv9s | 7.2 | 15.23–20.87 | 26.7 |
| YOLOv10n | 2.3 | 8.91–14.78 | 6.5 |
| YOLOv10s | 7.2 | 9.11–14.95 | 21.4 |