---
title: "What is image annotation?"
description: "Image annotation is human or model labels — boxes, captions, classes — stored on visual rows so training and review can reuse them."
url: "https://pixeltable.com/learn/what-is-image-annotation"
updated: "2026-09-29"
vertical: "Vision"
doc: "https://docs.pixeltable.com/platform/type-system"
---

# What is image annotation?

Image annotation is human or model labels — boxes, captions, classes — stored on visual rows so training and review can reuse them.

Updated: 2026-09-29


## On this page

- [How it works](https://pixeltable.com/learn/what-is-image-annotation#how-it-works)
- [What it is not](https://pixeltable.com/learn/what-is-image-annotation#what-it-is-not)
- [Comparison](https://pixeltable.com/learn/what-is-image-annotation#comparison)
- [Where Pixeltable fits](https://pixeltable.com/learn/what-is-image-annotation#where-pixeltable-fits)
- [Questions](https://pixeltable.com/learn/what-is-image-annotation#questions)

## How it works {#how-it-works}


- The image or frame is the row.
- A person or a model writes labels onto that row.
- Training and review read the same rows.

## What it is not {#what-it-is-not}

It is not a labeling product that never runs your models, and it is not labels trapped in an export file.

## image annotation: this, and the thing it is confused with {#comparison}

|  | This | Not this |
| --- | --- | --- |
| Lives on | The media row | A separate labeling project |
| Who writes | A person, a model, or both | Only a vendor UI |
| Reuse | The same table trains and audits | A dumped JSON |

## Where Pixeltable fits {#where-pixeltable-fits}

Pixeltable stores labels as columns beside the image. A labeling tool can still be where people draw; the table is where the labels stay.

## Questions {#questions}

### How does image annotation work? {#faq-1}

The image or frame is the row. A person or a model writes labels onto that row. Training and review read the same rows.

### What is image annotation often confused with? {#faq-2}

It is not a labeling product that never runs your models, and it is not labels trapped in an export file.

## In the blog

- [Multimodal Annotation Tools Comparison 2025: Encord vs Label Studio vs Labelbox vs SuperAnnotate](https://pixeltable.com/blog/multimodal-annotation-tools-comparison-2025)
- [Accelerating Multimodal AI Data Annotations with Pixeltable](https://pixeltable.com/blog/accelerating-multimodal-ai-data-annotations-pixeltable)
- [From Data Chaos to Dataset Mastery: How ML Engineers Are Transforming Autonomous Vehicle Workflows](https://pixeltable.com/blog/ml-engineer-dataset-chaos-autonomous-vehicle-workflows)

## Related

- [Documentation](https://docs.pixeltable.com/platform/type-system)
- [Accelerating Multimodal AI Data Annotations with Pixeltable](https://pixeltable.com/blog/accelerating-multimodal-ai-data-annotations-pixeltable)
- [Multimodal Annotation Tools Comparison 2025: Encord vs Label Studio vs Labelbox vs SuperAnnotate](https://pixeltable.com/blog/multimodal-annotation-tools-comparison-2025)
- [Pixeltable vs Label Studio](https://pixeltable.com/compare/pixeltable-vs-labelstudio)
- [Pixeltable vs Voxel51](https://pixeltable.com/compare/pixeltable-vs-voxel51)