On a single randomly generated test set (real-DIV2K val), RealESRNet achieves a higher average PSNR than BSRNet (24.93 dB vs 24.77 dB), suggesting RealESRNet is superior. However, under SEAL's systematic evaluation on 100 representative degradation cases, BSRNet achieves AR 0.55 while RealESRNet achieves only AR 0.15, meaning BSRNet outperforms the FSRCNN acceptance line on 55% of cases versus 15% for RealESRNet. Across 20 random test sets, the PSNR difference between the two ranges from -0.22 to 0.18 dB, making the conventional ranking unstable.
Evidence
correlational
Key metric
PSNR on real-DIV2K val: RealESRNet 24.93 dB vs BSRNet 24.77 dB; AR on DIV2K-SE: BSRNet 0.55 vs RealESRNet 0.15; PSNR difference across 20 random sets ranges from -0.22 to 0.18 dB
Caveat
The conventional test set uses a single random sampling of degradations; the SEAL test set uses 100 cluster centers from spectral clustering of 10,000 sampled degradations.