LabelU
LabelU is an open-source platform for annotating image, video, and audio data, intended for work that supports complex data analysis and model training.
What LabelU is
LabelU is an open-source platform for annotating image, video, and audio data, intended for work that supports complex data analysis and model training. Image tools cover 2D bounding boxes, semantic segmentation, polylines, and keypoints; video and audio tools cover segmentation, classification, and information extraction. You can load pre-annotated data and refine it, or use AI model services to detect and segment image objects, including in batches with progress tracking. The platform imports annotation data from S3-compatible storage such as AWS S3 and MinIO, and exports JSON, COCO, and MASK formats. For local deployment, its listed setup uses Miniconda, Python 3.11, pip, and a server at http://localhost:8000/. LabelU includes SQLite and supports MySQL installation and migration. Its model server exposes HTTP POST / and GET /health endpoints. Florence-2 and GroundingDINO with SAM ViT-B each require about 4GB VRAM; SAM 3 requires about 8GB and CUDA 12.6 or later. The project uses the Apache 2.0 license.
Good
- Covers image, video, and audio annotation.
- Imports data from S3-compatible storage.
- Exports JSON, COCO, and MASK formats.
- Supports pre-annotated data refinement.
- Offers a unified HTTP model-server API.
Watch out
- Local setup requires Miniconda and Python 3.11.
- SAM 3 requires about 8GB VRAM and CUDA 12.6+.
- The listed local server runs at localhost:8000.
Who it suits
LabelU suits teams annotating image, video, or audio data for analysis and model training. It is also a fit for users who want to host an annotation platform and review or refine model-assisted labels.
Verdict
LabelU brings multiple annotation modalities, model assistance, storage imports, and common export formats into an open-source platform. Check its local setup and model hardware requirements against your environment before choosing it.
The facts
Each one read from LabelU's own pages, with the date it was checked.
What it does
- AI assistance
- Users can load pre-annotated data in one click and refine it in the platform.checked 2 Oct 2001
- AI assisted labeling
- Users can load pre-annotated data with one click and refine or adjust it.checked 1 Oct 2001
- AI auto-annotation
- Image auto-annotation can detect and segment objects, with batch task annotation and real-time progress tracking.checked 2 Oct 2001
- API
- The model server exposes a unified HTTP API with POST / and GET /health endpoints.checked 1 Oct 2001
- Audio annotation
- Audio tools support audio segmentation, audio classification, and audio information extraction.checked 1 Oct 2001
- Audio tools
- Audio annotation supports segmentation, classification, and information extraction.checked 2 Oct 2001
- Database support
- SQLite is the documented default database, and MySQL can be installed as an optional dependency.checked 2 Oct 2001
- Deployment
- The project documents local installation with Python 3.11 or later and running a local server at localhost:8000.checked 2 Oct 2001
- Export formats
- The README lists JSON, COCO, and MASK among supported export formats.checked 2 Oct 2001
- Image annotation
- Image tools include 2D bounding boxes, semantic segmentation, polylines, and keypoints.checked 1 Oct 2001
- Image tools
- Image annotations include 2D bounding boxes, semantic segmentation, polylines, and keypoints.checked 2 Oct 2001
- Intended users
- The README describes the platform as suited to annotation work supporting complex data analysis and model training.checked 2 Oct 2001
- License
- The project is released under the Apache 2.0 license.checked 2 Oct 2001
- Model requirements
- Florence-2 requires about 4GB VRAM, GroundingDINO plus SAM ViT-B about 4GB, and SAM 3 about 8GB with CUDA 12.6+.checked 1 Oct 2001
- Object storage
- LabelU can import annotation data from S3-compatible storage such as AWS S3 and MinIO.checked 1 Oct 2001
- Purpose
- LabelU is an open-source multimodal data annotation platform for image, video, and audio tasks.checked 2 Oct 2001
- Reference models
- The project lists Florence-2, GroundingDINO with SAM ViT-B, and SAM 3 reference model servers, with GPU memory requirements stated for each.checked 2 Oct 2001
- Storage integration
- LabelU can import files from S3-compatible storage, including AWS S3 and MinIO.checked 2 Oct 2001
- Support
- The project README invites users to join the official OpenDataLab WeChat group.checked 1 Oct 2001
- Support channel
- The project README invites users to join the OpenDataLab official WeChat group.checked 2 Oct 2001
- Video annotation
- Video capabilities include video segmentation, video classification, and video information extraction.checked 1 Oct 2001
- Video tools
- Video annotation supports segmentation, classification, and information extraction.checked 2 Oct 2001
Alternatives to LabelU
- 1
Label Studio
Free planOpen sourceWebAPILinuxmacOS8.2From $99 a month - 2
Roboflow
Free planAndroidiOSWebAPI7.5From $39 a month - 3
CVAT
Free planWebAPISelf-hosted6.8From $1.92 a month - 4
Supervisely
Free planWebAPISelf-hosted6.8From €199 a month - 5
doccano
Free planAndroidiOSWebAPI6.7Free plan - 6
Prodigy
WebAPILinuxmacOS6.7$390, paid once