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MusicXML import drops piano-family MIDI programs when the instrument name isn't recognized #2084
Description
music21 version
10.5.0
Problem summary
When a part's <midi-program> is one music21 maps to Piano (MusicXML programs 1–6), the importer replaces that instrument with the one made from <instrument-name>. That makes sense when the name is recognized, since exporters often write piano as a default program. But when the name isn't recognized, the replacement is a plain Instrument with no midiProgram, so the program is lost. Other programs are kept.
Steps to reproduce
from music21 import converter, instrument
def score(midi_program):
return f'''<score-partwise version="4.0">
<part-list><score-part id="P1"><part-name>Music</part-name>
<score-instrument id="P1-I1"><instrument-name>Doubler</instrument-name></score-instrument>
<midi-instrument id="P1-I1"><midi-program>{midi_program}</midi-program></midi-instrument>
</score-part></part-list>
<part id="P1"><measure number="1">
<attributes><divisions>1</divisions></attributes>
<note><pitch><step>C</step><octave>4</octave></pitch><duration>4</duration><type>whole</type></note>
</measure></part>
</score-partwise>'''
for midi_program in (41, 1, 2):
parsed = converter.parse(score(midi_program), format='musicxml')
print(midi_program, [(type(i).__name__, i.midiProgram)
for i in parsed.recurse().getElementsByClass(instrument.Instrument)])Expected vs. actual behavior
Expected a midiProgram of 40, 0 and 1. Actual:
41 [('Violin', 40)]
1 [('Instrument', None)]
2 [('Instrument', None)]
More information
The replacement is in MeasureParser's score-part handling (musicxml/xmlToM21.py):
# 2. midiProgram is Piano (often this is encoded only as piano for convenience)
if inst_from_name.midiProgram == i.midiProgram or isinstance(i, instrument.Piano):
i = inst_from_nameThis isn't asking to remove the piano rule, only to not lose the program when the name doesn't give an instrument, for example by only replacing when the name was recognized, or by keeping i.midiProgram on the replacement.
Activity