Fig. 1. Structure of the generator

Fig. 2. Network structure after removing the BN layer

Fig. 3. Structure of the RRDB

Fig. 4. Structure of the discriminator

Fig. 5. Schematic diagram of the training process. (a) Actual training curve; (b) ideal training curve^[16]

Fig. 6. Training environment of the network

Fig. 7. Interface of the MOI test system

Fig. 8. PSNR of different algorithms in the Set5 test set

Fig. 9. SSIM of different algorithms on the Set5 test set

Fig. 10. PSNR of different algorithms on the Set14 test set

Fig. 11. SSIM of different algorithms in the Set14 test set

Fig. 12. Reconstruction effects of two algorithms. (a) Original image; (b) SRGAN algorithm; (c) our algorithm

Fig. 13. Reconstruction results of 5 different algorithms. (a) Overall original image; (b) bicubic interpolation algorithm;(c) SRCNN algorithm; (d) VDSR algorithm; (e) SRResNet algorithm; (f) our algorithm; (g) partial original image

Fig. 14. Railroad track image reconstructed by 5 different algorithms. (a) Overall original image; (b) bicubic interpolation algorithm; (c) SRCNN algorithm; (d) VDSR algorithm; (e) SRResNet algorithm; (f) our algorithm; (g) partial original image