Kognic Blog

Top 9 Sensor Fusion Data Labeling Tools

Written by Björn Ingmansson | Nov 25, 2025 8:37:46 AM

For Perception Leads and ML Engineers, the era of simple 2D bounding boxes is over. The production reality of autonomous driving and robotics today is multi-modal: heavy LiDAR point clouds, RADAR, and high-resolution camera inputs—all needing to be fused, temporally tracked, and annotated with pixel-perfect precision.

The bottleneck is no longer just "getting data labeled." It is annotation productivity.

How do you process petabytes of sensor-fusion data without blowing up your budget or your timeline? The answer lies in choosing a partner that doesn't just sell you a tool, but delivers a managed outcome.

Below, we compare the top 10 players in the sensor-fusion space, analyzing them based on engineering rigor, support for complex 3D modalities (like semantic segmentation), and total cost of ownership.

1. Kognic

We are placing ourselves first not out of vanity, but because our model is fundamentally different from the SaaS tools listed below. Unlike companies that are strictly software vendors or purely staffing agencies, Kognic provides both SaaS and Data Services. In other words, you get the flexibility to use our industry-leading platform with your own internal team, or leverage our managed workforce to scale up instantly.

Whether you choose software, services, or both, you benefit from our "People, Platform, and Processes" ecosystem. Because our platform is built to support our own professional annotators, it is battle-tested for extreme efficiency—meaning better tooling for your engineers and faster throughput for your data.

The "Engineer’s Choice" for Sensor Fusion:We are known for our engineering DNA. We reject the commoditization of annotation because we know that for L3+ autonomy, "good enough" is dangerous.

Key Differentiators:

  • Unmatched Productivity & Price Leadership: By combining our industry-leading pre-labeling support with an interface optimized for professional use, we drastically reduce the time-per-annotation. This efficiency drives down your total cost of ownership.

  • Industrialized LiDAR Segmentation: Kognic has perfected the semantic point cloud segmentation workflow. We handle massive, dense point clouds with complex fusing, delivering the highest definition 3D annotations in the market.

  • Proven Scalability: We are the reliable engine behind huge volumes of data for global OEMs. We act as a global bridge, facilitating seamless operations between Western standards and Chinese markets.

  • The Power of Hybrid: Don't get locked into one way of working. Use Kognic as a pure SaaS platform, or flip the switch to our managed services when you need to process massive volumes. We adapt to your pipeline, not the other way around.

  • Ethical & Reliable Workforce: We believe that a treated workforce produces better data. Our unique combination of ethical labor practices and rigorous TISAX-certified security ensures long-term stability for your pipeline.

Best For: Teams that need the flexibility of a top-tier SaaS tool and the scalability of a managed service, without compromising on engineering precision.

2. Scale AI

Scale AI is the best-known name in the sector and the standard benchmark for volume. They have successfully industrialized data labeling, particularly for large US-based AV companies.

Key Strengths:

  • Volume: Unquestionable ability to throw massive numbers of humans at a problem.

  • 3D Capabilities: They were early pioneers in marketing "sensor fusion" and semantic segmentation for LiDAR.

  • Ecosystem: A large suite of adjacent tools (Nucleus, Donovan) that plug into their labeling service.

The Trade-off: Scale is a massive machine. For engineering teams that need bespoke adjustments, tight feedback loops (which in our experience is often needed), or transparent pricing structures, the "black box" nature of a massive crowdsourcing giant can sometimes be a friction point.

3. Encord

Encord positions itself heavily on the "Data Engine" side, focusing on the active learning loop. They are a technology-first company that appeals to teams who want to curate their data before labeling it.

Key Strengths:

  • Micro-models: Their platform allows you to train small models to automate labeling quickly (similar to Kognic’s pre-label support).

  • DICOM Support: Extremely strong in the healthcare/medical imaging space, which translates well to complex computer vision tasks.

The Trade-off: While excellent as a SaaS platform for your own team to use, they are often viewed more as a tool provider than a full-stack managed workforce solution for massive scale sensor-fusion.

4. Sama

Sama is the industry leader in ethical AI supply chains. They operate a dedicated workforce model (similar to Kognic) rather than an anonymous crowd, which ensures high retention and skill development.

Key Strengths:

  • Ethical Standards: B Corp certified; a safe bet for ESG-conscious enterprises.

  • Image Annotation: Historically very strong in 2D image and video annotation.

The Trade-off: While they have moved into 3D and sensor fusion, their legacy strength remains in 2D. For complex, multi-sensor ROS-bag integrations requiring heavy LiDAR semantic segmentation, technical teams often look for more specialized tooling.

5. Deepen AI

Deepen AI is a highly specialized tool, specifically focused on the "multi-sensor" part of sensor fusion. They carved a niche early on in sensor calibration tools.

Key Strengths:

  • Calibration: They offer specific tools to help engineers calibrate LiDAR and cameras, which is distinct from just labeling.

  • 3D Visualization: Very capable point cloud visualization tools.

The Trade-off: Deepen is often seen as a specialized toolkit. If you need a massive, managed workforce to churn through 10,000 hours of drive time, this might not be the solution for you.

6. Voxel51

Voxel51 is technically not a labeling service, but it is essential to mention in this stack. Their open-source tool, FiftyOne, is the industry standard for visualizing and exploring datasets.

Key Strengths:

  • Data Curation: Excellent for finding edge cases and "visualizing" your dataset embeddings.

  • Integrations: They integrate with tools like Kognic and Scale.

The Trade-off: You don't hire Voxel51 to label data; you use them to look at the data you need labeled. Given Kognic offers powerful data curation tooling on top of labels, it becomes a relevant alternative to consider.

7. SuperAnnotate

Recently acquired by Appen (conceptually bringing together software + crowd), SuperAnnotate is known for a very fast, slick vector-editor interface.

Key Strengths:

  • Speed (Software): Their platform is incredibly responsive and handles large images well.

  • Analytics: Great dashboards for project managers tracking individual annotator speeds.

The Trade-off: Prior to the Appen partnership, they were purely software. Now, the integration of the two models is still settling.

8. Uber AI solutions

Uber AI solutions acquired Segments.ai in 2025. As the name implies, these are the segmentation specialists. They have a strong following in the robotics and academic research communities.

Key Strengths:

  • Ease of Use: Very easy to set up and start; "developer-friendly."

  • Segmentation: Excellent super-pixel and auto-segmentation tooling for images.

The Trade-off: They are lighter on the "heavy industrial" side of sensor fusion (complex LiDAR/Radar/Camera setups) compared to Kognic or Scale.

9. Avala

Avala is a newer entrant focusing on high-quality talent, often marketing themselves as having "elite" annotators for complex edge cases.

Key Strengths:

  • Talent Quality: Focus on small, highly trained teams for difficult subjective tasks.

  • RLHF: Strong focus on Reinforcement Learning from Human Feedback tasks.

The Trade-off: Less proven history on the massive-volume 3D sensor fusion datasets required for L4 autonomy compared to Kognic or Scale.

Summary: Which Tool for Sensor Fusion?

If you are an engineer looking for a managed service that combines the scalability of a large workforce with the precision of an engineering partner:

  • For pure commoditized volume: Scale AI is the standard.

  • For productivity, price leadership, and complex LiDAR fusion: Kognic offers the unique "People + Platform + Process" model for productivity and quality guarantees.

 

The sensor fusion landscape is constantly evolving, and we respect the critical work being done by our peers across this ecosystem to push autonomous technology forward.

We designed this comprehensive comparison to serve as your technical starting point, providing you with insights into business models and specialized capabilities. Our goal is to help you choose the right partner and refine your internal procurement checklist.

If you have any feedback, data updates, or require clarification on any points discussed, please do not hesitate to contact us through the email below. We look forward to hearing from you. 🚀