README

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Background

This example demonstrates how to visualize and work with MCAP files in Rerun. From mcap.dev:

MCAP (pronounced "em-cap") is an open source container file format for multimodal log data. It supports multiple channels of timestamped pre-serialized data, and is ideal for use in pub/sub or robotics applications.

MCAP is the default bag format in ROS 2 and is rapidly gaining adoption. You can read more about Rerun's MCAP support here.

In this guide, you will learn:

1. How to load MCAP files directly into the Rerun viewer.
2. How to convert MCAP files into native Rerun data files (RRD).
3. How to convert older ROS bags (ROS 1 and ROS 2 SQLite3) into MCAP.
4. How to read and deserialize MCAP/RRD data in Python for programmatic processing and advanced visualization in Rerun.

We will use a dataset from the JKK Research Center containing LiDAR, images, GPS, and IMU data. The workflow involves converting the original ROS 1 bag → MCAP → RRD, and then using Python to log the RRD data with specific Rerun components for optimal visualization.

Follow the tutorial and run the code

This is an external example. Check the mcap_example repository for more information.