🏷 Open Source Data Annotation & Labeling Tools

At ZenML we believe that annotation and labeling workflows are a core part of the machine learning lifecycle. As an open-source tool, we wanted to highlight and recognize the variety of tools that are available to help your workflows become more data-centric. We had three core criteria to decide whether a particular tool could make it into the list:

• The tool has an open-source licence.
• The tool is actively maintained.
• The tool is functional and fit for purpose.

We welcome contributions to this list, so if you know of a tool that we've missed or if you've built one yourself, please do create a PR!

🔥 Do you use these tools or do you want to add one to your MLOps stack? At ZenML, we are looking for design partnerships and collaboration to develop the integrations and workflows around using annotation within the MLOps lifecycle. If you'd like to learn more, please join our Slack and leave us a message!

Contents

• Multi Modal / Multi Domain
• Text
• Images
• Audio
• Video
• Time Series
• Other

Multi Modal / Multi Domain

Name	Description	License
Acharya	A Data Centric MLOps tool for your Named Entity Recognition projects	?
Classifai	A comprehensive open-source data annotation platform	Apache-2
Computer Vision Annotation Tool (CVAT)	A free, online, interactive video and image annotation tool for computer vision	MIT
Data Annotator for Machine Learning (DAML)	An application that helps machine learning teams facilitating the creation and management of annotations	Apache-2
DataGym	Open source annotation and labeling tool for image and video assets	MIT
Diffgram	Training Data (Data Labeling, Annotation, Workflow) for all Data Types (Image, Video, 3D, Text, Geo, Audio, more) at scale	ELv2
Hover	Explore and label on a map of raw data. Handles text, audio and images.	MIT
Label Studio	A multi-type data labeling and annotation tool with standardized output format	Apache-2
Pigeon	A simple widget that lets you quickly annotate a dataset of unlabeled examples from the comfort of your Jupyter notebook	Apache-2
Tator	Video analytics web platform	AGPL-3
TornadoAi	A human-in-the-loop machine learning framework	AGPL-3
Universal Data Tool	A web/desktop app for editing and annotating images, text, audio, documents and to view and edit any data defined in the extensible .udt.json and .udt.csv standard	MIT
VGG Image Annotator (VIA)	A standalone image annotator application packaged as a single HTML file (< 400 KB) that runs on most modern web browsers	BSD-2
VIAME	Video and Image Analytics for Multiple Environments	Custom

Text

Name	Description	License
Annotation Lab	An NLP annotation tool included in spark-nlp	Apache-2
CoreNLP	A Java suite of core NLP tools	GPL-3
DataQA	Labeling platform for text using weak supervision	GPL-3
doccano	An open source text annotation tool supporting text classification, sequence labeling and sequence to sequence tasks	MIT
FLAT - FoLiA Linguistic Annotation Tool	A web-based linguistic annotation environment based around the FoLiA format, an XML-based format for linguistic annotation	GPL-3
INCEpTION	A semantic annotation platform offering intelligent annotation assistance and knowledge management	Apache-2
NER Annotator for Spacy	NER Annotator for SpaCy allows you to create training data for creating a custom NER Model with custom tags.	MIT
Rubrix	A production-ready Python framework for exploring, annotating, and managing data in NLP projects	Apache-2
SMART	A tool for building labeled training datasets for supervised machine learning tasks in NLP	MIT
SpaCy annotator	Spacy NER annotator using ipywidgets	N/A
TALEN	A way to do annotations for NER	Custom
YEDDA	A lightweight collaborative text span annotation tool	Apache-2

Images

Name	Description	License
Annotorious	A JavaScript library for image annotation	BSD-3
CATMAID	The Collaborative Annotation Toolkit for Massive Amounts of Image Data	GPL-3
COCO Annotator	A web-based image segmentation tool for object detection, localization, and keypoints	MIT
DeepLabel	A cross-platform desktop image annotation tool for machine learning	MIT
ilastik	Segment, classify, track and count your cells or other experimental data	Custom
ImageTagger	An open source online platform for collaborative image labeling	MIT
imglab	A web based tool to label images for objects that can be used to train dlib or other object detectors	MIT
KNOSSOS	A software tool for the visualization and annotation of 3D image data and was developed for the rapid reconstruction of neural morphology and connectivity	GPL-2
LabelFlow	An open platform for image labeling	Custom
labelme	Image Polygonal Annotation with Python (polygon, rectangle, circle, line, point and image-level flag annotation)	Custom
LabelImg	A graphical image annotation tool and label object bounding boxes in images	MIT
LOST	A flexible web-based framework for semi-automatic image annotation	MIT
Make Sense	A free-to-use online tool for labeling photos	GPL-3
OpenLabeler	An open source desktop application for annotating objects for AI appplications	Apache-2
Pixano	A web-based smart-annotation tool for computer vision applications	CeCILL-C
Scalabel	A web-based visual data annotation tool, supporting both 2D and 3D data labeling	Apache-2
webKnossos	A fully cloud- and browser-based 3D annotation tool for distributed large-scale data analysis in light- and electron-microscopy based Connectomics	AGPL-3

Video

Name	Description	License
DIVE	Media annotation and analysis tools for web and desktop	Apache-2

Audio

Name	Description	License
aubio	A library for audio and music analysis	GPL-3
audino	Open source audio annotation tool	MIT
Praat	Annotation tool for phonetics analysis	GPL-3
Peaks.js	JavaScript UI component for interacting with audio waveforms	LGPL-3
Wavesurfer.js	Navigable waveform built on Web Audio and Canvas	BSD-3

Time Series

Name	Description	License
sktime	A framework for machine learning with time series	BSD-3

Other

Name	Description	License
OpenCRAVAT	A modular annotation tool for genomic variants	MIT
Personal Cancer Genome Reporter (PCGR)	A stand-alone software package for translation of individual tumor genomes for precision cancer medicine	MIT

Acknowledgements

Thanks to the creators of these other repositories (and this one!) for getting us going down the path of creating our own. I used these efforts to get started in my survey of the space before adding, updating and pruning as per the open-source and other criteria specified above.