def timeSignatureToMidiEvents(ts):
'''Translate a m21 TiemSignature to a pair of events, including a DeltaTime.
>>> from music21 import *
>>> ts = meter.TimeSignature('5/4')
>>> eventList = timeSignatureToMidiEvents(ts)
>>> eventList[0]
<MidiEvent DeltaTime, t=0, track=None, channel=None>
>>> eventList[1]
<MidiEvent TIME_SIGNATURE, t=None, track=None, channel=1, data='\\x05\\x02\\x18\\x08'>
'''
mt = None # use a midi track set to None
eventList = []
dt = midiModule.DeltaTime(mt)
dt.time = 0 # set to zero; will be shifted later as necessary
# add to track events
eventList.append(dt)
n = ts.numerator
# need log base 2 to solve for exponent of 2
# 1 is 0, 2 is 1, 4 is 2, 16 is 4, etc
d = int(math.log(ts.denominator, 2))
metroClick = 24 # clock signals per click, clicks are 24 per quarter
subCount = 8 # number of 32 notes in a quarternote
me = midiModule.MidiEvent(mt)
me.type = "TIME_SIGNATURE"
me.channel = 1
me.time = None # not required
me.data = midiModule.putNumbersAsList([n, d, metroClick, subCount])
eventList.append(me)
return eventList
def keySignatureToMidiEvents(ks):
'''Convert a single MIDI event into a music21 TimeSignature object.
>>> from music21 import key
>>> ks = key.KeySignature(2)
>>> ks
<music21.key.KeySignature of 2 sharps>
>>> eventList = keySignatureToMidiEvents(ks)
>>> eventList[1]
<MidiEvent KEY_SIGNATURE, t=None, track=None, channel=1, data='\\x02\\x00'>
>>> ks = key.KeySignature(-5)
>>> ks
<music21.key.KeySignature of 5 flats>
>>> eventList = keySignatureToMidiEvents(ks)
>>> eventList[1]
<MidiEvent KEY_SIGNATURE, t=None, track=None, channel=1, data='\\xfb\\x00'>
'''
mt = None # use a midi track set to None
eventList = []
dt = midiModule.DeltaTime(mt)
dt.time = 0 # set to zero; will be shifted later as necessary
# add to track events
eventList.append(dt)
sharpCount = ks.sharps
if ks.mode == 'minor':
mode = 1
else: # major or None; must define one
mode = 0
me = midiModule.MidiEvent(mt)
me.type = "KEY_SIGNATURE"
me.channel = 1
me.time = None # not required
me.data = midiModule.putNumbersAsList([sharpCount, mode])
eventList.append(me)
return eventList
