Struct McapWriterOptions

Struct Documentation

struct McapWriterOptions

Options for an MCAP writer.

Public Functions

McapWriterOptions() = default

Public Members

Context context

The context to use for the MCAP writer.

std::string_view path

The path to the MCAP file. Ignored if custom_writer is set.

std::optional<CustomWriter> custom_writer

Custom writer for arbitrary destinations. If set, path is ignored.

std::string_view profile

The profile to use for the MCAP file.

uint64_t chunk_size = static_cast<uint64_t>(1024 * 768)

The size of each chunk in the MCAP file.

McapCompression compression = McapCompression::Zstd

The compression algorithm to use for the MCAP file.

bool use_chunks = true

Whether to use chunks in the MCAP file.

bool disable_seeking = false

Whether to disable seeking in the MCAP file.

bool emit_statistics = true

Whether to emit statistics in the MCAP file.

bool emit_summary_offsets = true

Whether to emit summary offsets in the MCAP file.

bool emit_message_indexes = true

Whether to emit message indexes in the MCAP file.

bool emit_chunk_indexes = true

Whether to emit chunk indexes in the MCAP file.

bool emit_attachment_indexes = true

Whether to emit attachment indexes in the MCAP file.

bool emit_metadata_indexes = true

Whether to emit metadata indexes in the MCAP file.

bool repeat_channels = true

Whether to repeat channels in the MCAP file.

bool repeat_schemas = true

Whether to repeat schemas in the MCAP file.

bool calculate_chunk_crcs = true

Whether to calculate and write CRCs for chunk records.

bool calculate_data_section_crc = true

Whether to calculate and write a data section CRC into the DataEnd record.

bool calculate_summary_section_crc = true

Whether to calculate and write a summary section CRC into the Footer record.

bool calculate_attachment_crcs = true

Whether to calculate and write CRCs for attachment records.

uint32_t compression_level = 0

Compression level passed to the underlying compressor (zstd or lz4). A value of 0 instructs the compressor to use its default level.

std::optional<uint32_t> compression_threads

Number of threads for zstd compression. 0 disables multithreading. The default (nullopt) uses the number of physical CPUs.

bool truncate = false

Whether to truncate the MCAP file.

SinkChannelFilterFn sink_channel_filter

Optional channel filter to use for the MCAP file.

Friends

friend class McapWriter