jtbandes
commented
2 years ago Thanks for reporting. I can reproduce the issue. This is a bug in the Python library.
You can work around the issue by using mcap convert --compression lz4 or --compression none.
Description After converting a ros1 .bag file to .mcap with
mcap convert rosbag.bag rosbag.mcapthe python library can't read more than the first record.First record:
Header(profile='ros1', library='mcap go #(devel)')ERROR:zstd.Error: Input data invalid or missing content size in frame header.Converting it with
mcap convert --chunked=False rosbag.bag rosbag.mcapmakes it able to be used with the python libary.Version mcap-cli: mcap-linux-amd64 (v0.0.8) Language: Python 3.8.10 libary: mcap (0.0.8) Platform: Ubuntu 20.04
Steps To Reproduce
Behavior /home/dragonking3x/PycharmProjects/testing/venv/bin/python /home/dragonking3x/PycharmProjects/testing/main.py Header(profile='ros1', library='mcap go #(devel)') Traceback (most recent call last): File "/home/dragonking3x/PycharmProjects/testing/main.py", line 100, in
main('PyCharm')
File "/home/dragonking3x/PycharmProjects/testing/main.py", line 28, in main
read_mcap(file_name)
File "/home/dragonking3x/PycharmProjects/testing/main.py", line 34, in read_mcap
for record in reader.records:
File "/home/dragonking3x/PycharmProjects/testing/venv/lib/python3.8/site-packages/mcap/mcap0/stream_reader.py", line 91, in records
chunk_records = breakup_chunk(record)
File "/home/dragonking3x/PycharmProjects/testing/venv/lib/python3.8/site-packages/mcap/mcap0/stream_reader.py", line 31, in breakup_chunk
stream, stream_length = get_chunk_data_stream(chunk)
File "/home/dragonking3x/PycharmProjects/testing/venv/lib/python3.8/site-packages/mcap/mcap0/stream_reader.py", line 53, in get_chunk_data_stream
data: bytes = ZSTD_uncompress(chunk.data)
zstd.Error: Input data invalid or missing content size in frame header.
INFO - 2022-05-12 12:14:05,747 - core - signal_shutdown [atexit]