| --- |
| pretty_name: MuSCAT RawImage |
| license: cc-by-nc-4.0 |
| viewer: false |
| tags: |
| - astronomy |
| - image |
| - remote-sensing |
| - scientific-data |
| - fits |
| - raw |
| - denoising |
| - astrophotography |
| - ccd |
| task_categories: |
| - image-to-image |
| language: |
| - en |
| --- |
| |
| # Dataset Card for MuSCAT-RawImage |
|
|
|
|
| ## Dataset Description |
|
|
| - **Dataset name:** MuSCAT-RawImage |
| - **Repository:** `ToferFish/MuSCAT-RawImage` |
| - **Source project:** [ShuhongLL/Denoising-Deep-Sky](https://github.com/ShuhongLL/Denoising-Deep-Sky) |
| - **License:** CC BY-NC 4.0 |
| - **Modality:** Astronomical raw CCD images and calibration products |
| - **Format:** Compressed FITS files (`.fits.fz`) plus JSON metadata |
|
|
| This dataset contains raw and processed astronomical CCD observations from the MuSCAT instruments, organized for deep-sky image denoising and related low-level image restoration research. |
| The repository structure follows the organization used in the Denoising-Deep-Sky project, where data are grouped by **instrument**, **band**, and **observation session**. |
|
|
| The data are intended primarily for: |
|
|
| - astronomical image denoising |
| - raw-to-clean image restoration |
| - CCD noise modeling |
| - calibration-aware image processing |
| - benchmarking denoising methods on real telescope data |
|
|
| ## Dataset Structure |
|
|
| The dataset is organized by instrument, spectral band, and observation session. |
|
|
| A typical directory layout is: |
|
|
| ```text |
| dataset_root/ |
| ├── muscat3_g/ |
| │ ├── <observation_id_1>/ |
| │ │ ├── calib/ |
| │ │ │ ├── BIAS_*.fits.fz |
| │ │ │ ├── BPM_*.fits.fz |
| │ │ │ ├── DARK_*.fits.fz |
| │ │ │ └── SKYFLAT_*.fits.fz |
| │ │ ├── data/ |
| │ │ │ ├── <obs_id>_calib.fits.fz |
| │ │ │ ├── <obs_id>_mask.fits.fz |
| │ │ │ ├── <obs_id>_mean.fits.fz |
| │ │ │ ├── <obs_id>_os.fits.fz |
| │ │ │ └── <obs_id>_raw.fits.fz |
| │ │ ├── e91/ |
| │ │ ├── calib.json |
| │ │ └── info.json |
| │ └── <observation_id_2>/ |
| │ └── ... |
| └── muscat4_i/ |
| └── ... |
| ``` |
|
|
| ## Data Contents |
|
|
| Each observation directory may include the following components. |
|
|
| ### Calibration files (`calib/`) |
|
|
| - `BIAS_*.fits.fz` |
| Master bias frame. Represents the electronic offset estimate. |
|
|
| - `BPM_*.fits.fz` (Empty) |
| Bad pixel map. |
|
|
| - `DARK_*.fits.fz` |
| Master dark-current template. |
|
|
| - `SKYFLAT_*.fits.fz` |
| Sky flat used for pixel-response and vignetting correction. |
|
|
| ### Observation data (`data/`) |
|
|
| - `<obs_id>_raw.fits.fz` |
| Raw CCD frame. |
|
|
| - `<obs_id>_os.fits.fz` |
| Overscan-corrected frame, typically used as the noisy input. |
|
|
| - `<obs_id>_calib.fits.fz` |
| Calibrated frame. |
|
|
| - `<obs_id>_mean.fits.fz` |
| High-SNR stacked reference frame built from multiple exposures. |
|
|
| - `<obs_id>_mask.fits.fz` |
| Background/source mask. |
|
|
| ### Additional files |
|
|
| - `e91/` |
| Additional calibrated frames used to construct stacked references. |
|
|
| - `calib.json` |
| Calibration-related metadata. |
|
|
| - `info.json` |
| Observation/session metadata. |
|
|
| ## Data Fields |
|
|
| This repository does not follow a tabular row-based structure. |
| Instead, each sample is stored as a set of FITS files and JSON metadata under one observation directory. |
|
|
| Important file-level fields include: |
|
|
| - **instrument**: e.g. MuSCAT-3 or MuSCAT-4 |
| - **band**: e.g. `g`, `r`, `i` |
| - **observation_id**: identifier for one observation session |
| - **raw frame**: original CCD image |
| - **overscan-corrected frame**: original CCD image - overscan |
| - **calibrated frame**: processed image using calibration products |
| - **mean frame**: stacked high-SNR reference image |
| - **mask**: source/background mask (background = 1, source = 0) |
| - **calibration metadata**: gain, dark, bias, flat-related information when available |
| |
| ## Supported Tasks and Use Cases |
| |
| This dataset is suitable for: |
| |
| - real-world astronomical image denoising |
| - supervised image-to-image restoration |
| - physics-based CCD noise modeling |
| - calibration-aware low-level vision |
| - benchmarking telescope image restoration pipelines |
| |
| Possible training pairs include: |
| |
| - original pairs: `*_os.fits.fz` ----> `*_calib.fits.fz` |
| - synthesized pairs: `*_syn.fits.fz` ----> `*_mean.fits.fz` |
| |
| Depending on the experiment design, users may also incorporate: |
| |
| - `*_raw.fits.fz` |
| - `*_calib.fits.fz` |
| - calibration frames from `calib/` |
| - masks from `*_mask.fits.fz` |
| |
| ## Loading the Data |
| |
| Because the dataset is distributed as FITS files instead of a standard row-based file format such as CSV or Parquet, it is generally intended to be accessed as files from the repository rather than directly through the default Hugging Face dataset viewer. |
| |
| Example with Python: |
| |
| ```python |
| from astropy.io import fits |
| |
| path = "muscat3_g/<observation_id>/data/<obs_id>_raw.fits.fz" |
| |
| with fits.open(path) as hdul: |
| image = hdul[1].data |
| header = hdul[1].header |
| |
| print(image.shape) |
| print(header) |
| ``` |
| |
| ## Citation |
| If you use this dataset, please cite the original project: |
| ```bibtex |
| @misc{liu2025denoisingdeepsky, |
| title={Denoising the Deep Sky: Physics-Based CCD Noise Formation for Astronomical Imaging}, |
| author={Shuhong Liu and Xining Ge and Ziying Gu and Quanfeng Xu and Ziteng Cui and Lin Gu and Xuangeng Chu and Jun Liu and Dong Li and Tatsuya Harada}, |
| year={2025}, |
| eprint={2508.08079}, |
| archivePrefix={arXiv}, |
| primaryClass={cs.CV} |
| } |
| ``` |
