---
license: cc-by-4.0
task_categories:
- object-detection
---
# CFC26-Mini Dataset Card

## Dataset Summary

**CFC26-Mini** is a curated sample of the full **CFC26** dataset — a large-scale benchmark for fish detection and counting in underwater ARIS sonar video collected across 9 field locations in North America. This mini version is intended for demonstration purposes.

> **Note:** This is a sample of the full CFC26 dataset. The full dataset contains thousands of clips and hundreds of thousands of annotated frames across all locations and splits. See [Full Dataset](https://huggingface.co/datasets/perona-lab/cfc26/) for details.

---

## Dataset Details

| Property | Value |
|---|---|
| **Task** | Fish detection, counting |
| **Annotation format** | COCO JSON (bounding boxes + track IDs) |
| **License** | CC BY 4.0 |

---

## Sampling Methodology

CFC26-Mini is constructed from the full CFC26 dataset using the following procedure:

- **1 clip** sampled per split (train / val / test) per location
- **10 frames** sampled per clip
- Only frames containing **at least one fish annotation** are included (positive samples only)
- Temporal train/val/test splits are inherited from the full CFC26 dataset splits

---

## Dataset Structure

```
cfc26-mini/
├── {location}/
│   └── {clip_name}/
│       └── *.png / *.jpg          # 3-channel representations (fish-positive only)
```

Each location directory contains up to 3 clip subdirectories (one per split). Frame filenames encode the clip identity and frame index:

```
{clip_name}_{frame_index}.png  # png and/or jpg
```

---

## Locations

The mini dataset includes samples from the following field sites:

| Location | Region |
|---|---|
| Chemainus | British Columbia, Canada |
| Dungeness | Washington, USA |
| Eel | California, USA |
| Elwha | Washington, USA |
| Channel | Alaska, USA |
| Kenai | Alaska, USA |
| Rightbank | Alaska, USA |
| Klamath | California, USA |
| Mad | California, USA |
| Nanaimo | British Columbia, Canada |
| Nushagak | Alaska, USA |

---

## Data Fields

Each frame is a 3-channel representation made up of the raw frame, the background-subtracted frame, and the difference between consecutive background-subtracted frames. Annotations are provided in COCO JSON format alongside the full dataset.

**COCO annotation fields per bounding box:**

| Field | Description |
|---|---|
| `bbox` | `[x, y, width, height]` in pixels (top-left origin) |
| `track_id` | Unique fish identity within a clip |
| `category_id` | Fish category (FISH) |
| `image_id` | Links to the corresponding frame |

---

## Full Dataset

The full **CFC26** dataset contains:
- Locations across Alaska, California, Washington, and British Columbia
- Thousands of annotated clips spanning multi-week deployments per site
- Temporal train/val/test splits designed to evaluate generalization across time
- Complete COCO JSON annotations with bounding boxes and track IDs
- Per-clip ARIS sonar metadata (frame rate, pixel scale, window parameters)

The full dataset is available at: *(link to be added upon release)*

---

## Limitations

- **Positive samples only.** CFC26-Mini contains exclusively fish-positive frames (frames with at least one fish annotation). Empty frames — which constitute a significant portion of the full dataset — are not included. Models trained or evaluated on this mini dataset will not be exposed to the true class imbalance present in real deployments.
- **1 clip per split per location.** A single clip is unlikely to be representative of the full temporal and environmental variation within a location.
- **10 frames per clip.** Frames are randomly sampled for this demonstration and are not sequential. Temporal context (motion, track continuity) is not preserved.
- **Not for benchmarking.** Results on CFC26-Mini are not comparable to results reported on the full CFC26 dataset. Use the full dataset for all benchmark evaluation.

---

## Citation

*(Citation will be updated with full details upon publication.)*

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## License

CFC26-mini is released under the Creative Commons Attribution 4.0 International [CC BY 4.0 License](https://creativecommons.org/licenses/by/4.0/deed.en).