Learning from Failure: Leveraging Unreliable Predictions in Semi-Supervised Real-World Adverse Weather Removal
Organizations: College of Computing and Data Science, Nanyang Technological University, Singapore
Abstract
Adverse weather image restoration aims to recover images degraded by rain, haze, snow, and other weather-induced artifacts, thereby improving the robustness of outdoor vision systems. Existing unified restoration models exhibit limited generalization to real-world scenes due to their reliance on synthetic supervision and insufficient semantic constraints. In this paper, we propose a novel student--teacher semi-supervised framework that addresses both challenges. Specifically, we introduce an unreliable database that preserves failed teacher predictions as informative negative samples for contrastive learning, while a reliable database stores high-quality teacher predictions as positive samples. By jointly exploiting reliable pseudo-ground truths and unreliable teacher outputs, the proposed framework learns to enhance desirable restoration characteristics while avoiding common failures. We further propose a phase spectrum-based semantic constraint that replaces computationally expensive text-based supervision with an efficient and naturally aligned semantic prior. An adaptive phase consistency loss is also designed to dynamically balance supervision between the degraded input and teacher pseudo-ground truths according to degradation severity. Extensive experiments on real-world benchmarks demonstrate that the proposed method consistently outperforms existing state-of-the-art approaches in restoration quality and perceptual fidelity while exhibiting stronger generalization to real-world adverse weather conditions.
Figures & tables
| Models | Rain | Snow | Haze | Average | #Param | FLOP | |||||
| Name | Year | LIQE | CLIP-IQA | LIQE | CLIP-IQA | LIQE | CLIP-IQA | LIQE | CLIP-IQA | M | G |
| Restormer | CVPR22 | 2.277 | 0.437 | 3.172 | 0.510 | 1.918 | 0.366 | 2.456 | 0.438 | 26.12 | 141.00 |
| TransWeather | CVPR22 | 1.924 | 0.358 | 2.770 | 0.416 | 1.502 | 0.292 | 2.065 | 0.355 | 38.05 | 12.24 |
| TKL | CVPR22 | 2.028 | 0.392 | 2.830 | 0.428 | 1.590 | 0.318 | 2.149 | 0.379 | 28.47 | 49.22 |
| WeatherDiffusion | TPAMI23 | 2.050 | 0.395 | 2.950 | 0.466 | 1.520 | 0.326 | 2.173 | 0.396 | 82.96 | 475.16 |
| WGWS-Net | CVPR23 | 1.965 | 0.389 | 2.619 | 0.395 | 1.506 | 0.310 | 2.030 | 0.365 | 5.19 | 13.61 |
| Models | RAIN100L | |
| PSNR | SSIM | |
| UMR | 32.39 | 0.921 |
| SIRR | 32.37 | 0.926 |
| MSPFN | 33.50 | 0.948 |
| LPNet | 33.61 | 0.958 |
| AirNet | 34.90 | 0.977 |
| Models | H | S | R | H+S | H+R | R*+S | H+S+R* |
| PSNR /SSIM | PSNR /SSIM | PSNR /SSIM | PSNR /SSIM | PSNR /SSIM | PSNR /SSIM | PSNR /SSIM | |
| MODEM | 19.73 / 0.8789 | 27.72/0.8953 | 23.76 / 0.9029 | 17.87 / 0.7918 | 20.16/0.8801 | 20.34/0.6734 | 14.23 /0.4327 |
| HOGFormer | 18.87/0.8693 | 28.96 / 0.9129 | 23.54/0.9051 | 16.51/0.7635 | 20.30 / 0.8876 | 20.41 / 0.6771 | 13.66/ 0.4557 |
| Ours | 19.89 / 0.8805 | 33.46 / 0.9568 | 24.01 / 0.9336 | 17.27 / 0.7874 | 21.36 / 0.9161 | 22.84 / 0.7390 | 14.45 / 0.5012 |
| Baseline | w/ | w/ unsupervised constraint | LIQE | CLIP-IQA | |||
| w/o unreliable database | w/ unreliable database | LPIPS | Text | Phase | |||
| x | 2.390 | 0.402 | |||||
| x | x | 2.429 | 0.445 | ||||
| x | x | 3.098 | 0.525 | ||||
| x | x | x | 3.368 | 0.565 | |||
| x | x | x | 3.407 | 0.545 | |||
| NR-IQA | Rain | Snow | Haze | |||
| LIQE | CLIP-IQA | LIQE | CLIP-IQA | LIQE | CLIP-IQA | |
| LIQE | 1.029 | 0.418 | 1.013 | 0.389 | 1.032 | 0.453 |
| MUSIQ | 1.774 | 0.469 | 2.507 | 0.532 | 1.329 | 0.420 |
| NIMA | 2.194 | 0.516 | 2.228 | 0.610 | 2.995 | 0.468 |
| CLIP-IQA | 2.445 | 0.553 | 3.120 | 0.603 | 1.696 | 0.508 |
| RALI | 3.466 | 0.597 | 3.852 | 0.611 | 3.263 | 0.507 |
| Degradation types | Metrics | Choices of | ||
| L1 | Contrastive | Ours | ||
| Rain | LIQE | 3.302 | 3.380 | 3.466 |
| CLIP-IQA | 0.592 | 0.593 | 0.597 | |
| Snow | LIQE | 3.742 | 3.862 | 3.852 |
| CLIP-IQA | 0.596 | 0.612 | 0.611 | |
| Haze | LIQUE | 3.136 | 3.192 | 3.263 |
Appendix figures & tables9 assets
Supplementary material from the paper’s appendix.
Appendix
| Degradation type | Methods | |||
| HOGFormer | Ours | |||
| Phase | Amplitude | Phase | Amplitude | |
| Rain | 52.645 | 12.331 | 33.735 | 8.836 |
| Snow | 62.657 | 9.616 | 58.644 | 8.953 |
| Haze | 57.057 | 11.604 | 32.623 | 6.545 |
| Avg | 57.453 | 11.184 | 41.667 | 8.111 |
| Method | Trainable Param | Latency | GPU Mem | Model Size |
| M | ms | MB | MB | |
| MODEM | 19.96 | 100.83 | 551.21 | 77 |
| HOGformer | 16.65 | 218.82 | 760.43 | 65 |
| Ours | 19.67 | 21.20 | 497.08 | 225 |
| Method | Latency | GPU mem | Average Performance | |
| ms | MB | LIQE | CLIP-IQA | |
| Using LPIPS | 2.14 | 1774.66 | 3.368 | 0.565 |
| Using Text | 1198.14 | 13846.31 | 3.407 | 0.545 |
| Using Phase | 41.00 | 2894.09 | 3.527 | 0.572 |
| Backbone | Trainable Param | FLOP | Average Performance | |
| M | G | LIQE | CLIP-IQA | |
| NAFNet | 67.89 | 290.84 | 3.545 | 0.574 |
| Uformer | 5.29 | 42.74 | 3.268 | 0.497 |
| MSBDN | 19.67 | 153.94 | 3.527 | 0.572 |
| Method | AP | AP by Object Size | ||||
| IoU=0.5:0.95 | IoU=0.5 | IoU=0.75 | Small | Medium | Large | |
| Uformer | 29.6 | 31.3 | 29.9 | 37.5 | 27.3 | 27.9 |
| AirNet | 31.0 | 32.9 | 32.1 | 36.1 | 26.6 | 30.7 |
| PromptIR | 31.2 | 33.7 | 32.3 | 42.1 | 29.9 | 31.1 |
| DFPIR | 28.8 | 30.9 | 29.8 | 27.4 | 26.4 | 30.1 |
| Ours | 35.3 | 38.7 | 36.6 | 44.4 | 29.9 | 35.3 |
| Degradation types | Metrics | Methods | |
| HOGformer | Ours | ||
| Rain | Q-Align | 2.8022 | 2.8372 |
| MUSIQ | 53.958 | 55.776 | |
| Snow | Q-Align | 2.7557 | 2.6678 |
| MUSIQ | 54.947 | 52.336 | |
| Haze | Q-Align | 2.4597 | 2.5241 |