⚠️ This type is unstable and may change significantly in a way that the data won't be backwards compatible. Recording-level statistics about an MCAP file.

This archetype contains summary information about an entire MCAP recording, including counts of messages, schemas, channels, and other records, as well as timing information spanning the full recording duration. It is typically logged once per recording to provide an overview of the dataset's structure and content.

See also archetypes.McapChannel for individual channel definitions, archetypes.McapMessage for message content, archetypes.McapSchema for schema definitions, and the MCAP specification for complete format details.

Fields

Required

• message_count: Count
• schema_count: Count
• channel_count: Count
• attachment_count: Count
• metadata_count: Count
• chunk_count: Count
• message_start_time: Timestamp
• message_end_time: Timestamp

Optional

• channel_message_counts: ChannelMessageCounts

Can be shown in

• DataframeView

API reference links

• 🌊 C++ API docs for McapStatistics
• 🐍 Python API docs for McapStatistics
• 🦀 Rust API docs for McapStatistics

Example

Simple MCAP statistics

"""Log simple MCAP recording statistics."""

import rerun as rr

rr.init("rerun_example_mcap_statistics", spawn=True)

rr.log(
    "mcap/statistics/recording_overview",
    rr.McapStatistics(
        message_count=12500,
        schema_count=3,
        channel_count=5,
        attachment_count=2,
        metadata_count=8,
        chunk_count=25,
        message_start_time=1743465600000000000,  # 2024-04-01 00:00:00 UTC in nanoseconds
        message_end_time=1743466200000000000,  # 2024-04-01 00:10:00 UTC in nanoseconds (10 minute recording)
    ),
)