| --- |
| license: cc-by-4.0 |
| task_categories: |
| - image-to-image |
| - unconditional-image-generation |
| tags: |
| - microscopy |
| - electron-microscopy |
| - HAADF-STEM |
| - nanoparticles |
| - simulation |
| - materials-science |
| - webdataset |
| size_categories: |
| - 100K<n<1M |
| configs: |
| - config_name: default |
| data_files: |
| - split: train |
| path: "train-*.tar" |
| --- |
| |
| # Nanoparticle Size Estimation Dataset (WebDataset) |
|
|
| 100,000 simulated HAADF-STEM images of nanoparticles with three image variants per sample (raw simulation, normalized, and CycleGAN style-transferred), paired with per-structure metadata including atomic coordinates, morphology, and simulation parameters. |
|
|
| ## Dataset Description |
|
|
| Synthetic HAADF-STEM images of Pt nanoparticles on various support interfaces, generated for nanoparticle size and morphology prediction. Each sample includes the raw simulation output, a set-normalized version, and a CycleGAN-transferred version that emulates experimental noise characteristics. Associated with the paper [Nanoparticle size estimation](https://pubs.acs.org/doi/10.1021/acs.nanolett.4c06025). |
|
|
| Original data: [Zenodo record 14608502](https://zenodo.org/records/14608502) |
|
|
| ## Format |
|
|
| WebDataset format: 20 TAR shards (~1 GB each), 19 GB total. |
|
|
| Each sample in a shard contains: |
| - `{idx:06d}.sim_raw.npy` — raw simulated HAADF-STEM image (128x128, float32) |
| - `{idx:06d}.sim_norm.npy` — set-normalized simulation (128x128, float32) |
| - `{idx:06d}.cyclegan.npy` — CycleGAN style-transferred image (128x128, float32) |
| - `{idx:06d}.json` — metadata |
|
|
| ### Metadata Fields |
|
|
| | Field | Type | Description | |
| |-------|------|-------------| |
| | `sample_id` | int | Original sample index | |
| | `original_filename` | string | Original .npy filename | |
| | `width` | int | Image width (128) | |
| | `height` | int | Image height (128) | |
| | `pixel_size` | float | Pixel size in Angstroms | |
| | `beam_offset_x` | float | Beam offset in x | |
| | `beam_offset_y` | float | Beam offset in y | |
| | `particle_rotation` | float | Particle rotation angle (radians) | |
| | `structure_type` | string | Nanoparticle morphology (cluster, wulff, random, etc.) | |
| | `support_interface` | string | Support surface orientation (e.g., 111, 100, random) | |
| | `particle_interface` | string | Particle surface orientation | |
| | `element` | string | Atomic species (Pt) | |
| | `subset` | string | Dataset subset label (e.g., AC_111_111) | |
| | `n_atoms` | int | Number of atoms in the structure | |
| | `raw_min` | float | Minimum pixel intensity (raw image) | |
| | `raw_max` | float | Maximum pixel intensity (raw image) | |
| | `raw_mean` | float | Mean pixel intensity (raw image) | |
| | `raw_std` | float | Std dev of pixel intensity (raw image) | |
|
|
| ### Image Properties |
|
|
| - **Count:** 100,000 samples (300,000 images total across 3 variants) |
| - **Format:** NumPy arrays (.npy), float32 |
| - **Resolution:** 128x128 |
| - **Modality:** Synthetic HAADF-STEM |
| - **Element:** Pt nanoparticles |
| - **Morphologies:** cluster, wulff, random |
|
|
| ## Usage |
|
|
| ```python |
| import webdataset as wds |
| import numpy as np |
| from torch.utils.data import DataLoader |
| |
| url = "path/to/nanoparticle_wds/train-{0000..0019}.tar" |
| dataset = wds.WebDataset(url).decode().shuffle(1000) |
| dataloader = DataLoader(dataset, batch_size=64, num_workers=4) |
| |
| for sample in dataloader: |
| raw_image = sample[".sim_raw.npy"] |
| norm_image = sample[".sim_norm.npy"] |
| cyclegan_image = sample[".cyclegan.npy"] |
| metadata = sample[".json"] |
| ``` |
|
|
| ## Source |
|
|
| Original data from [Zenodo record 14608502](https://zenodo.org/records/14608502). Associated paper: [Nano Letters (2024)](https://pubs.acs.org/doi/10.1021/acs.nanolett.4c06025). |
|
|
| ## License |
|
|
| CC-BY-4.0 |
|
|
