def end_of_track(self):
"""
Writes the track to the buffer.
>>> from mxm.midifile.src.data_type_converters import readBew
>>> midi_out = MidiOutFile()
>>> midi_out.start_of_track()
>>> midi_out.note_on(channel=0, note=0x40, velocity=0x40)
>>> midi_out.end_of_track()
>>> r = list(midi_out.read_all())
>>> r
[77, 84, 114, 107, 0, 0, 0, 8, 0, 144, 64, 64, 0, 255, 47, 0]
>>> bytes(r[:4]), readBew(r[4:8]), r[8:12], r[12:16]
(b'MTrk', 8, [0, 144, 64, 64], [0, 255, 47, 0])
"""
raw = self.raw_out
raw.writeSlice(c.TRACK_HEADER)
# track_data = self._current_track_buffer.getvalue()
track_data = self._current_track_buffer.read_all()
eot_slice = bytes(writeVar(self.rel_time())) + bytes(
[c.META_EVENT, c.END_OF_TRACK, 0])
# wee need to know size of track data.
track_length = len(track_data) + len(eot_slice)
raw.writeBew(track_length, 4)
# then write
raw.writeSlice(track_data)
raw.writeSlice(eot_slice)
self._current_track_buffer.close()
del self._current_track_buffer
def sysex_event(self, data):
"""
data: list of values in range(128)
"""
super().system_exclusive(data)
sysex_slice = bytearray([c.SYSTEM_EXCLUSIVE])
sysex_slice += bytearray(writeVar(len(data) + 1)) # sysex_len
sysex_slice += data
sysex_slice += bytearray([c.END_OFF_EXCLUSIVE])
self.event_slice(sysex_slice)
def sequencer_specific(self, id, data):
"""
id: manufacturer id. 1 or 3 bytes long.
data: The data as byte values
"""
super().sequencer_specific(id, data)
data = bytes(data)
len_data = len(id) + len(data)
len_data = writeVar(len_data)
seq_slice = bytes(len_data) + bytes(id) + data
self.meta_slice(c.SEQUENCER_SPECIFIC, seq_slice)
def meta_slice(self, meta_type, data_slice):
"""
Writes a meta event. meta_type is a byte from constants. data_slice is bytes
>>> midi_out = MidiOutFile()
>>> midi_out.start_of_track()
>>> midi_out.meta_slice(meta_type=c.TEXT, data_slice=b'pimpf')
>>> midi_out.end_of_track()
>>> r = list(midi_out.read_all())
>>> bytes(r[12:17])
b'pimpf'
"""
slc = bytearray()
slc.append(c.META_EVENT) # this is a meta event
slc.append(meta_type) # the specific meta event.
slc += bytes(writeVar(len(data_slice)))
slc += data_slice
self.event_slice(slc)
def writeVarLen(self, value):
"Writes a variable length word to the file"
self.writeSlice(writeVar(value))