Music21, window 分析有时间吗?

Music21, window analysis get time?

我尝试了 music21 的 WindowAnalysis。但是我想知道如何将 window 的索引转换为歌曲的时间(以秒为单位)。例如,我怎么知道第一个 window 播放的时间?例如进入歌曲 2.5 秒

s = music21.converter.parse('../data/medley/15046.midi')

p = music21.analysis.discrete.KrumhanslSchmuckler()
wa = music21.analysis.windowed.WindowedAnalysis(s, p)
windo_count=4
a, b = wa.analyze(windo_count)
song = pm.PrettyMIDI('../data/medley/15046.midi')
cello_program = pm.instrument_name_to_program('Cello')
cello = pm.Instrument(program=cello_program)

prev=a[0]
change_loc=[]
#some code that detects change and should append now the time in seconds
for i,beat in enumerate(a[1:]):
    #i is the tuple (key,major/minor/etc,time)
    if beat[0]!=prev[0] and beat[1]!=prev[1]:
        #key changed, at index
        change_loc.append(my_question)

使用 pretty_midi 可以获得从节拍到时间的映射,例如

import pretty_midi as pm
song = pm.PrettyMIDI('data/medley/15046.midi')
print(song.get_beats())

编辑: 可以在此处找到更多信息: