Format support

ROS2 .db3 bag support: where things stand

Short version: LidarFlow does not read .db3 files yet. It reads ROS1 .bag and .mcap. If you have a .db3 recording, converting it to MCAP takes one command and then the normal pipeline works.

Supported today

· ROS1 .bag
· .mcap, recorded from ROS1 or ROS2
· LiDAR published as sensor_msgs/PointCloud2

Not supported: ROS2 .db3 (the rosbag2 SQLite storage format). The upload validator rejects it rather than failing halfway through a run.

Why .db3 is a separate problem

A .db3 bag is a SQLite database, not a message stream on disk. Reading it means going through the rosbag2 storage layer, and the message payloads inside are CDR-serialised against ROS2 type definitions rather than the ROS1 message definitions embedded in a classic bag. MCAP sidesteps both problems: it is a self-describing container that carries schema information alongside the messages, which is exactly why the ROS2 ecosystem has been moving toward it.

What to do right now with a .db3 file

Convert it to MCAP with the official rosbag2 CLI. Install the MCAP storage plugin for your distro (ros-$ROS_DISTRO-rosbag2-storage-mcap), write a small conversion config, and run:

# convert.yaml
output_bags:
  - uri: my_bag_mcap
    storage_id: mcap
    all_topics: true

# then
ros2 bag convert -i my_bag -o convert.yaml

Reference: ros2/rosbag2 and mcap.dev. Once you have the .mcap, follow MCAP to point cloud.

Want native .db3 support?

It is on the roadmap without a date attached. Leave an email and we will tell you when the validator accepts .db3 directly. Nothing else gets sent to that address.

Frequently asked questions

Does LidarFlow support ROS2 bag files?

Only when they are recorded as MCAP. ROS2 recordings using the default SQLite storage plugin (.db3) are not accepted by the upload validator today. ROS1 .bag and .mcap both work.

How do I convert a .db3 file to MCAP?

Install the rosbag2 MCAP storage plugin, then run: ros2 bag convert -i my_bag -o convert.yaml, with an output entry setting storage_id to mcap. The resulting .mcap file can be uploaded to LidarFlow directly.

Will ROS2 .db3 support be added?

It is on the roadmap. There is no ship date to promise yet, which is why this page has a waitlist rather than a countdown.

What formats does LidarFlow support today?

ROS1 .bag and .mcap, with LiDAR data published as sensor_msgs/PointCloud2 (or ROS1 Livox CustomMsg). IMU and GNSS topics are optional and auto-detected.