Sequence Track Name MIDI messages wrongly null-terminated

• Sep 7, 2020 - 22:20
Reported version
3.5
Type
Functional
Frequency
Few
Severity
S4 - Minor
Reproducibility
Always
Status
closed
Regression
No
Workaround
No
Project
MuseScore

Create a one-measure file with an instrument named Classical Guitar.
Insert a note.
Export to midi.

Inspect the MIDI file -- the Sequence Track Name message is null-terminated:
In python:
>>> binascii.unhexlify('ff0311436c6173736963616c204775697461720000')
b'\xff\x03\x11Classical Guitar\x00\x00'

Impact:
A MIDI importer, such as music21, might ingest the empty byte into the part name and then generate malformed musicxml when trying to write 'Classical Guitar\x00' as the part-name.

Another user verified this on a forum post on this topic:
https://musescore.org/en/node/310149
I confirm seeing the same here with MuseScore 3.5.1.13199/Windows 7.

That item in MIDI is not to be null-terminated (there is an explicit length parameter in the meta-event encoding.)

Attachment Size
emptyByte.mid 118 bytes
emptyByte.mscz 3.15 KB

Comments

• Sep 27, 2020 - 14:02
Frequency Few ⇒ Many

Raising frequency because it happens every time MIDI is exported, and we are starting to get bug reports at music21 over it.

Reply

• Jan 25, 2022 - 09:35
Reported version 3.5 ⇒ 3.6

This problem resurfaced in the current stable and nightly build.
If I export a midi score from MuseScore and run this simple Python script:

import os,sys
import muspy

midi = muspy.read_midi('midi_file.mid')
print([track.name for track in midi.tracks])

It outputs something like ['Piano\x00', 'Strings\x00'] instead of ['Piano', 'Strings'], happens only if the MIDI file was exported from MuseScore.

Reply

Fix version
4.0.0