Changing the 'note_off' property doesn't affect the 'duration_sec' property

[Lelant]

I noticed something. Not sure if it is a bug. I have a PerformedPart. When I change the note_off property of a note, then the duration_sec property of the corresponding note_array() stays the same.

Here is an example of how I encountered this phenomenon:

print(performedPart.notes[0])
print(performedPart.note_array()[0])

performedPart.notes[0]['note_off'] += 1.3

print(performedPart.notes[0])
print(performedPart.note_array()[0])

I print the values of the first note before and after changing the note_off value. I can see that this value has changed accordingly. The note_array() shows two types of duration, but not a note_off value. It shows the duration_sec and the duration_tick. Now in my output I see that the value of duration_sec has not changed, but the value of duration_tick has changed as expected.

Am I missing something or is this a bug or is this intentional?

I noticed this because of using the Piano Roll. After changing the note_off value, the new created piano roll shows the same as before. So it seems the piano roll uses this duration_sec value, that hasn't changed.

For now I found a workaround. For changing the length of a note I now use the note_array()'s property duration_sec instead of note_off. And after the change I overwrite my notes of the PerformedPart with the changed note_array(). Like so:

performanceNoteArray = performedPart.note_array()
performanceNoteArray[0]['duration_sec'] += 1.3
performedPart = pt.performance.PerformedPart.from_note_array(performanceNoteArray)

But I'm still curious if it should be possible to get a correct result in the piano roll just with changing note_off

Thanks a lot, Tim

[Lelant]

I also noticed another related thing.

When I set the note_on and note_off values of notes of a performedPart by hand, and when I then try to compute the piano roll, I get the following error message: (coming from file partitura/utils/music.py, line 1316)

raise ValueError("Note durations should be >= 0!")

But as I set the note_on and note_off values by myself, I know that they should result in positive durations for the notes. Here is how I did set the values:

note_on_val = 0.0
note_off_val = 1.0
for note in performedPart.notes:
        note['note_on'] = note_on_val
        note['note_off'] = note_off_val
        note_on_val += 1.0
        note_off_val += 1.0

So it looks like changing properties of performedPart.notes doesn't effect the note_array() that is generated to compute the piano roll (at least I guess that the piano roll uses the note_array() and not the .notes property)

[sildater]

Hi!

sorry for the late answer! This behavior is bit confusing. Here's a script that explains the main cases:

import partitura as pt
import numpy as np
performedPart = pt.load_performance_midi(pt.EXAMPLE_MIDI)[0]

# when creating a note array, 
# and the SOUND_OFF property is available, 
# it's used for duration_sec -> no change due to NOTE_OFF
print("changes in 'note_off' don't show up in note array, if there is a 'sound_off'")
print("original 'note_off': ",performedPart.notes[0]['note_off'])
print("same note in note array ",performedPart.note_array()[0])
performedPart.notes[0]['note_off'] += 1.0
print("changed 'note_off': ",performedPart.notes[0]['note_off'])
print("note in note array ",performedPart.note_array()[0])
print("dtypes of note array 'onset_sec', 'duration_sec','onset_tick','duration_tick'")

print("-----------------------------")
# when creating a note array, 
# and the NOTE_OFF_TICK property is UNavailable, 
# NOTE_OFF is used for duration_sec -> change due to NOTE_OFF
for n in performedPart.notes:
    n.pop('note_on_tick', None)
    n.pop('note_off_tick', None)
print("delete the NOTE_OFF_TICK and the the tick values are inferred from 'note_off' and not 'sound_off'.")
print("the 4th value in note array ('duration_ticks') is higher than before, and inconsistent with the other duration")
print("same note in note array ",performedPart.note_array()[0])
print("dtypes of note array 'onset_sec', 'duration_sec','onset_tick','duration_tick'")

# for manipulations of the performedpart: change both 'sound_off' and 'note_off', for consistency delete all ticks information

print("-----------------------------")
# when creating a performedpart from note_array, 
# only the times in seconds are used...
print("when creating the a performedpart from note_array, times in seconds are used")
na_to_change = np.copy(performedPart.note_array())
print("original note in note array ",na_to_change[0])
print("original 'note_off' in performedpart ", pt.performance.PerformedPart.from_note_array(na_to_change).notes[0]["note_off"])
print("change 'duration_tick'")
na_to_change[0]["duration_tick"] = 17
print("changed note in note array ", na_to_change[0])
print("UNCHANGED 'note_off' in performedpart ", pt.performance.PerformedPart.from_note_array(na_to_change).notes[0]["note_off"])
print("change 'duration_sec'")
na_to_change[0]["duration_sec"] = 100.
print("changed note in note array ", na_to_change[0])
print("CHANGED 'note_off' in performedpart ", pt.performance.PerformedPart.from_note_array(na_to_change).notes[0]["note_off"])

# for manipulations of the note_array: change both values in seconds, 'onset_sec' / 'duration_sec', tick times are discarded

The main points are the comments underneath the tests:

• for manipulations of the performedpart: change both 'sound_off' and 'note_off', for consistency delete all ticks information (also for onset times use 'note_on', not the value in ticks)
• for manipulations of the note_array: change both values in seconds, 'onset_sec' / 'duration_sec', tick times are discarded

The next release will address the negative duration issue, the rest remains as is for now. I hope you can find a workaround!

[Lelant]

Alright, thank you! This is very helpful :)