M3D-Stereo: A Multiple-Medium and Multiple-Degradation Dataset for Stereo Image Restoration

M3D-Stereo is a real-captured stereo image restoration dataset covering four degradation scenarios: underwater scatter (UWST), underwater low-light (UWLL), haze/fog scatter (HZST), and coupled haze low-light (HZLL). Each scenario provides 16 scenes at six progressive degradation levels (D1–D6) with pixel-aligned clear ground truths, captured by two calibrated ZED stereo cameras (Camera 1 / Camera 2, denoted c1 / c2).

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File Structure

M3D-Stereo/
├── UWST/                              # Underwater scatter
│   ├── scene1/
│   │   ├── d1/
│   │   │   ├── c1/ image_left/  image_right/
│   │   │   └── c2/ image_left/  image_right/
│   │   ├── d2/ ... d5/
│   │   └── d6/
│   │       ├── c1/ image_left/  image_right/
│   │       └── c2/ image_left/  image_right/
│   ├── scene2/ ... scene15/
│   └── scene16/
│
├── UWLL/                              # Underwater low-light
│   ├── scene1/ ... scene16/           (same structure as UWST)
│
├── HZST/                              # Haze/fog scatter
│   ├── scene1/ ... scene16/           (same structure as UWST)
│
├── HZLL/                              # Coupled haze + low-light
│   ├── scene1/ ... scene16/           (same structure as UWST)
│
├── UW_GT/                             # Ground truths for UWST & UWLL
│   ├── scene1/
│   │   ├── c1/ image_left/  image_right/
│   │   └── c2/ image_left/  image_right/
│   ├── scene2/ ... scene15/
│   └── scene16/
│
├── HZ_GT/                             # Ground truths for HZST & HZLL
│   ├── scene1/
│   │   ├── c1/ image_left/  image_right/
│   │   └── c2/ image_left/  image_right/
│   ├── scene2/ ... scene15/
│   └── scene16/
│
└── Camera_Parameters/
    ├── HZ/
    │   ├── c1/  HZ_c1.txt
    │   └── c2/  HZ_c2.txt
    └── UW/
        ├── c1/  UW_c1.txt
        └── c2/  UW_c2.txt

• c1 / c2: two stereo camera systems, independently calibrated for air and underwater environments.
• image_left / image_right: rectified stereo image pairs at 1920×1080.
• GT images are captured under clean-medium and full illumination conditions with identical scene layout, ensuring pixel-wise alignment with degraded inputs across all levels.

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Dataset Statistics

Subset	Scenes	Degradation	Levels	GT Source
UWST	scene1–scene16	Underwater scatter (milk concentration)	D1–D6	UW_GT
UWLL	scene1–scene16	Underwater low-light (PWM dimming)	D1–D6	UW_GT
HZST	scene1–scene16	Haze/fog scatter (fog machine duration)	D1–D6	HZ_GT
HZLL	scene1–scene16	Coupled haze + low-light	D1–D6	HZ_GT

Each scene contains stereo pairs from two cameras (c1, c2) across six degradation levels, yielding a total of 16 × 6 × 2 = 192 stereo-pair groups per degradation subset.

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Camera Parameters

Two ZED Mini stereo cameras are used. The UW camera pair operates in an underwater housing; the HZ camera pair operates in air. Each camera is independently calibrated using a 7×7 symmetric circle grid (15 mm spacing) via OpenCV stereo calibration. Full calibration files (intrinsics, distortion, rotation, translation, and rectification maps) are provided under Camera_Parameters/.

Camera	Focal Length (px)	Principal Point (px)	Baseline (mm)	Reproj. Error (px)
UW c1 left	1869.37, 1875.38	996.62, 594.86	62.98	0.046
UW c1 right	1871.29, 1876.57	987.59, 558.72		0.043
UW c2 left	1874.22, 1888.86	971.47, 637.44	62.81	0.047
UW c2 right	1870.74, 1885.61	998.86, 622.44		0.054
HZ c1 left	1401.27, 1400.39	991.60, 520.24	62.79	0.034
HZ c1 right	1401.12, 1400.67	986.85, 490.90		0.034
HZ c2 left	1401.81, 1401.30	971.40, 529.15	62.81	0.039
HZ c2 right	1399.04, 1398.84	993.80, 511.61		0.038

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License

This dataset is released under the LGPLv3 License.

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Citation

@article{yang2026m3dstereo,
  title   = {M3D-Stereo: A Multiple-Medium and Multiple-Degradation Dataset for Stereo Image Restoration},
  author  = {Deqing Yang and Yingying Liu and Qicong Wang and Zhi Zeng and Dajiang Lu and Yibin Tian},
  journal = {arXiv preprint arXiv:2604.12917},
  year    = {2026},
  url     = {https://arxiv.org/abs/2604.12917}
}