# Image Annotation

Source: https://www.potatoannotator.com/docs/guides/image-annotation

**Image annotation ranges from a single label per image to precise regions drawn on the pixels, boxes, polygons, and points.** The right level depends on what your model needs: a classifier needs labels, a detector needs [bounding boxes](https://en.wikipedia.org/wiki/Minimum_bounding_box), and a segmentation model needs polygons. For the feature reference see [Image Annotation](/docs/features/image-annotation).

## Whole-image classification and tagging

Use `radio` for one label, `multiselect` for several. The [image classification showcase](/showcase/image-classification) is a working example.

```yaml
annotation_schemes:
  - annotation_type: multiselect
    name: contents
    description: "Select everything visible in the image."
    labels: [Person, Vehicle, Animal, Building, Vegetation]
```

## Regions: boxes, polygons, landmarks

For localization, annotators draw on the image:

- **Bounding boxes** for [object detection](https://en.wikipedia.org/wiki/Object_detection).
- **Polygons** for [image segmentation](https://en.wikipedia.org/wiki/Image_segmentation), where object shape matters.
- **Landmarks / keypoints** for poses and faces.

Potato's image annotation supports these region types with per-class colors, the same way [span annotation](/docs/guides/span-annotation) works for text.

## Boundary and labeling rules

- **Tightness.** Do boxes hug the object or include a margin? Be consistent.
- **Occlusion and truncation.** Decide how to box a partly hidden object.
- **Small objects and crowds.** Set a minimum size and a rule for dense scenes.

These rules drive your agreement far more than the drawing tool does.

## Export for vision models

Potato exports image annotations to [COCO](https://cocodataset.org/) and YOLO formats, which detection and segmentation training pipelines read directly. See [Exporting Annotations for ML](/docs/guides/exporting-annotations-for-ml).

## Further reading

- [Image Annotation feature reference](/docs/features/image-annotation)
- [Video Annotation](/docs/guides/video-annotation)
- [LLM and Vision Pre-Annotation](/docs/guides/llm-pre-annotation)