MIDI with negative beginning tick

[Natooz]

Hey, 👋

I encountered a case where a specific MIDI file from the Lakh dataset got it's first tick before 0. 10e903c3aa7a6b6c5ce5a74d5cfb8702.mid.zip

When inspecting tracks, the 14th (idx 13) note of the 19th (idx 18) track has a time at -4465856

for ti, track in enumerate(score.tracks):
    for ni, note in enumerate(track.notes):
        if note.time < 0:
            test = 0

Didn't have to to dig further yet, I'll just leave this open

[Yikai-Liao]

This looks like an int overflow is occurring, I'll check further.

[lzqlzzq]

Seems same problem occurred in mido.

[Natooz]

I found other MIDIs for which the resample operation shifts some of their events to negative time values midis.zip They all have in common very large end tick values.

To reproduce:

from pathlib import Path
from symusic import Score

paths = list(Path("midis").glob("**/*.mid"))
for path in paths:
    score = Score(path)
    score = score.resample(12, min_dur=1)
    start_tick = score.start()

[Yikai-Liao]

@Natooz This is an int overflow caused by improper multiplication order during resample.

I've adjusted the order of multiplication in the resample and these examples no longer overflow. But an inappropriate resample can still cause an overflow, so I've further added an overflow check to determine if the scaled time is still valid.

[Natooz]

Wonderful thank you!