End-to-end data preparation services

Project and workflow design
Data collection
Data labeling
Annotator team curation
Data curation
Continuous QA
Guideline definition
Data augmentation
Continuous optimization

Throughout the entire data preparation process, we collaborate closely with your team to provide you with highest-quality AI training data and expert guidance. From curating balanced and representative data, to tailoring annotator teams, processes and tools to your specific use case, we bring a human touch to each step of the way.

Challenges we solve


Each AI project has unique training data needs. With our decades-long experience in the data preparation space, we design end-to-end strategies customized to your project...


Sourcing the right data is the first step in assuring quality and reducing biases in AI. We support you in creating, curating and augmenting datasets that are relevant, representative...


With over 25,000 project managers, annotators and linguists across the globe, we build your annotation team to best fit your project. Supported by data labeling automation technology...

Use cases

Collecting and Facilitating Natural Conversations in Specific Dialects

How do you coordinate 1000+ conversations between unique pairs of specific dialect speakers in just 2 months? With automation and the right pool of linguists.

Embedding Data Annotation into Search Algorithm Development

When iterating on a running search algorithm, engineers turned to Sigma’s flexible annotation teams to evaluate queries and respond to changes on the fly.

Pixel-Perfect Annotation for Recognizing Products in Images

A robotics client struggled to get high-quality image data labeled within a 1-pixel tolerance. Sigma.AI’s human-in-the-loop, tech-assisted teams delivered.

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Annotation services


Languages and dialects offered


Video frames and images analyzed daily


Hours of audio annotated


Words analyzed daily

Speech and text

From scanned documents to recorded dialogues to spontaneous speech in a noisy environment, we have deep experience annotating all forms of speech and text. We cover 300+ languages and dialects from speakers of all ages, genders and abilities.

Transcription & Diarization

Entity Recognition

Intent Recognition

Data Relevance

Sentiment and Emotion Analysis

Pronunciation and Dialect Assessment

Conversational AI Annotation

Translation and Localization

Content Moderation

Image & video

Through our customizable suite of labeling and annotation tools for visual media, we process a broad range of data types beyond standard image and video — including lidar and radar, thermal and x-ray.

2D and 3D Bounding Boxes


Lines and Splines

Landmark Annotation

Optical Character Recognition

Image Classification

Semantic Segmentation

Video Tracking

Let’s work together to build smarter AI

Whether you need help sourcing and annotating training data at scale, or you need a full-fledged annotation strategy to serve your AI training needs, we can help. Get in touch for more information or to set up your proof-of-concept.