# -*- coding: ISO-8859-1 -*- # std library from struct import unpack # custom from DataTypeConverters import readBew, readVar, varLen, toBytes # uhh I don't really like this, but there are so many constants to # import otherwise from constants import * class EventDispatcher: def __init__(self, outstream): """ The event dispatcher generates events on the outstream. """ # internal values, don't mess with 'em directly self.outstream = outstream # public flags # A note_on with a velocity of 0x00 is actually the same as a # note_off with a velocity of 0x40. When # "convert_zero_velocity" is set, the zero velocity note_on's # automatically gets converted into note_off's. This is a less # suprising behaviour for those that are not into the intimate # details of the midi spec. self.convert_zero_velocity = 1 # If dispatch_continuos_controllers is true, continuos # controllers gets dispatched to their defined handlers. Else # they just trigger the "continuous_controller" event handler. self.dispatch_continuos_controllers = 1 # NOT IMPLEMENTED YET # If dispatch_meta_events is true, meta events get's dispatched # to their defined events. Else they all they trigger the # "meta_event" handler. self.dispatch_meta_events = 1 def header(self, format, nTracks, division): "Triggers the header event" self.outstream.header(format, nTracks, division) def start_of_track(self, current_track): "Triggers the start of track event" # I do this twice so that users can overwrite the # start_of_track event handler without worrying whether the # track number is updated correctly. self.outstream.set_current_track(current_track) self.outstream.start_of_track(current_track) def sysex_event(self, data): "Dispatcher for sysex events" self.outstream.sysex_event(data) def eof(self): "End of file!" self.outstream.eof() def update_time(self, new_time=0, relative=1): "Updates relative/absolute time." self.outstream.update_time(new_time, relative) def reset_time(self): "Updates relative/absolute time." self.outstream.reset_time() # Event dispatchers for similar types of events def channel_messages(self, hi_nible, channel, data): "Dispatches channel messages" stream = self.outstream data = toBytes(data) if (NOTE_ON & 0xF0) == hi_nible: note, velocity = data # note_on with velocity 0x00 are same as note # off with velocity 0x40 according to spec! if velocity==0 and self.convert_zero_velocity: stream.note_off(channel, note, 0x40) else: stream.note_on(channel, note, velocity) elif (NOTE_OFF & 0xF0) == hi_nible: note, velocity = data stream.note_off(channel, note, velocity) elif (AFTERTOUCH & 0xF0) == hi_nible: note, velocity = data stream.aftertouch(channel, note, velocity) elif (CONTINUOUS_CONTROLLER & 0xF0) == hi_nible: controller, value = data # A lot of the cc's are defined, so we trigger those directly if self.dispatch_continuos_controllers: self.continuous_controllers(channel, controller, value) else: stream.continuous_controller(channel, controller, value) elif (PATCH_CHANGE & 0xF0) == hi_nible: program = data[0] stream.patch_change(channel, program) elif (CHANNEL_PRESSURE & 0xF0) == hi_nible: pressure = data[0] stream.channel_pressure(channel, pressure) elif (PITCH_BEND & 0xF0) == hi_nible: hibyte, lobyte = data value = (hibyte<<7) + lobyte stream.pitch_bend(channel, value) else: raise ValueError, 'Illegal channel message!' def continuous_controllers(self, channel, controller, value): "Dispatches channel messages" stream = self.outstream # I am not really shure if I ought to dispatch continuous controllers # There's so many of them that it can clutter up the OutStream # classes. # So I just trigger the default event handler stream.continuous_controller(channel, controller, value) def system_commons(self, common_type, common_data): "Dispatches system common messages" stream = self.outstream # MTC Midi time code Quarter value if common_type == MTC: data = readBew(common_data) msg_type = (data & 0x07) >> 4 values = (data & 0x0F) stream.midi_time_code(msg_type, values) elif common_type == SONG_POSITION_POINTER: hibyte, lobyte = toBytes(common_data) value = (hibyte<<7) + lobyte stream.song_position_pointer(value) elif common_type == SONG_SELECT: data = readBew(common_data) stream.song_select(data) elif common_type == TUNING_REQUEST: # no data then stream.tuning_request(time=None) def meta_event(self, meta_type, data): "Dispatches meta events" stream = self.outstream # SEQUENCE_NUMBER = 0x00 (00 02 ss ss (seq-number)) if meta_type == SEQUENCE_NUMBER: number = readBew(data) stream.sequence_number(number) # TEXT = 0x01 (01 len text...) elif meta_type == TEXT: stream.text(data) # COPYRIGHT = 0x02 (02 len text...) elif meta_type == COPYRIGHT: stream.copyright(data) # SEQUENCE_NAME = 0x03 (03 len text...) elif meta_type == SEQUENCE_NAME: stream.sequence_name(data) # INSTRUMENT_NAME = 0x04 (04 len text...) elif meta_type == INSTRUMENT_NAME: stream.instrument_name(data) # LYRIC = 0x05 (05 len text...) elif meta_type == LYRIC: stream.lyric(data) # MARKER = 0x06 (06 len text...) elif meta_type == MARKER: stream.marker(data) # CUEPOINT = 0x07 (07 len text...) elif meta_type == CUEPOINT: stream.cuepoint(data) # PROGRAM_NAME = 0x08 (05 len text...) elif meta_type == PROGRAM_NAME: stream.program_name(data) # DEVICE_NAME = 0x09 (09 len text...) elif meta_type == DEVICE_NAME: stream.device_name(data) # MIDI_CH_PREFIX = 0x20 (20 01 channel) elif meta_type == MIDI_CH_PREFIX: channel = readBew(data) stream.midi_ch_prefix(channel) # MIDI_PORT = 0x21 (21 01 port (legacy stuff)) elif meta_type == MIDI_PORT: port = readBew(data) stream.midi_port(port) # END_OFF_TRACK = 0x2F (2F 00) elif meta_type == END_OF_TRACK: stream.end_of_track() # TEMPO = 0x51 (51 03 tt tt tt (tempo in us/quarternote)) elif meta_type == TEMPO: b1, b2, b3 = toBytes(data) # uses 3 bytes to represent time between quarter # notes in microseconds stream.tempo((b1<<16) + (b2<<8) + b3) # SMTP_OFFSET = 0x54 (54 05 hh mm ss ff xx) elif meta_type == SMTP_OFFSET: try: hour, minute, second, frame, framePart = toBytes(data) stream.smtp_offset( hour, minute, second, frame, framePart) except ValueError: pass # TIME_SIGNATURE = 0x58 (58 04 nn dd cc bb) elif meta_type == TIME_SIGNATURE: try: nn, dd, cc, bb = toBytes(data) stream.time_signature(nn, dd, cc, bb) except ValueError, e: pass # KEY_SIGNATURE = 0x59 (59 02 sf mi) elif meta_type == KEY_SIGNATURE: sf, mi = toBytes(data) stream.key_signature(sf, mi) # SPECIFIC = 0x7F (Sequencer specific event) elif meta_type == SPECIFIC: meta_data = toBytes(data) stream.sequencer_specific(meta_data) # Handles any undefined meta events else: # undefined meta type meta_data = toBytes(data) stream.meta_event(meta_type, meta_data) if __name__ == '__main__': from MidiToText import MidiToText outstream = MidiToText() dispatcher = EventDispatcher(outstream) dispatcher.channel_messages(NOTE_ON, 0x00, '\x40\x40')