Fig. 1. Sample data set thumbnail of UAV

Fig. 2. Diagram of picture scale

Fig. 3. Data amplification

Fig. 4. ReLU function diagram

Fig. 5. Structure of convolutional neural network

Fig. 6. Self-made optical system

Fig. 7. UAV sample on-site collection diagram

Fig. 8. Loss function of 2 000 training times

Fig. 9. Accuracy variation diagram of 2 000 training times

Fig. 10. Comparison of recognition accuracy of different data sets

Fig. 11. Python experimental results

Fig. 12. Comparison of experimental results of different models