- [2026] Conference Proceeding available 🎉
- [2024] Paper accepted at WIRN 2024 🎉
- [2024] Code and experiments released
- [2024] Presentation available here
We propose a Diffusion GAN framework that significantly reduces the number of diffusion steps, making diffusion-based super-resolution much faster and more practical.
By leveraging the Discrete Wavelet Transform (DWT), the model operates in a compressed frequency domain, reducing computational cost while preserving fine details.
Our method achieves superior perceptual quality and reconstruction fidelity, outperforming strong baselines such as SR3, DiWa, and ESRGAN.
| Metric | ESRGAN | SR3 | DiWa | Ours |
|---|---|---|---|---|
| PSNR ↑ | 21.13 | 14.65 | 13.68 | 23.38 |
| SSIM ↑ | 0.59 | 0.42 | 0.13 | 0.68 |
| LPIPS ↓ | 0.082 | 0.365 | 0.336 | 0.061 |
| FID ↓ | 20.8 | 99.4 | 270 | 47.2 |
| Model | Runtime | Parameters |
|---|---|---|
| ESRGAN | 0.04s | 31M |
| SR3 | 60.3s | 98M |
| DiWa | 34.7s | 92M |
| Ours | 0.12s | 57M |
conda create --name=wadigan python=3.10
conda activate wadigan
pip install -r requirements.txtWe train on CelebA-HQ (16×16 → 128×128).
Download dataset:
Prepare dataset:
python datasets_prep/prepare_data.py \
--path [dataset root] \
--out [output root] \
--size 16,128 -l- Images must be sequentially numbered for LMDB conversion.
Structure:
data/
└── celebahq_16_128
We provide a unified script:
bash run.sh <DATASET> <MODE> <#GPUS>Example:
bash run.sh celebahq_16_128 train 1<DATASET>:celebahq_16_128<MODE>:train/test<#GPUS>: number of GPUs
--exp name for training and testing.
Metrics are computed on the full test set (6000 samples).
bash run.sh celebahq_16_128 test 1Add:
--compute_fid --real_img_dir /path/to/real/imagespython benchmark/eval.py -p [result root]Place checkpoints in:
saved_info/srwavediff/<DATASET>/<EXP>
Our framework combines:
- Diffusion models (reduced timesteps)
- GAN training paradigm
- Wavelet-domain processing
This enables:
- Faster inference
- Lower memory usage
- Improved texture reconstruction
- WaveDiff: https://github.com/VinAIResearch/WaveDiff
- SR3: https://github.com/Janspiry/Image-Super-Resolution-via-Iterative-Refinement
- DiWa: https://github.com/Brian-Moser/diwa
- ESRGAN: https://arxiv.org/abs/1809.00219
- BasicSR: https://github.com/XPixelGroup/BasicSR
- pytorch_wavelets: https://github.com/fbcotter/pytorch_wavelets
@Inbook{aloisi2026wavelet,
author="Aloisi, Lorenzo
and Sigillo, Luigi
and Uncini, Aurelio
and Comminiello, Danilo",
editor="Esposito, Anna
and Faundez-Zanuy, Marcos
and Morabito, Francesco Carlo
and Pasero, Eros
and Cordasco, Gennaro",
title="A Wavelet Diffusion GAN for Image Super-Resolution",
bookTitle="Neural Networks: Overview of Current Theories and Applications",
year="2026",
publisher="Springer Nature Singapore",
address="Singapore",
pages="425--435",
isbn="978-981-95-4072-3",
doi="10.1007/978-981-95-4072-3_36",
url="https://doi.org/10.1007/978-981-95-4072-3_36"
}

