Event-based Representation
- muspy.to_event_representation(music, use_single_note_off_event=False, use_end_of_sequence_event=False, encode_velocity=False, force_velocity_event=True, max_time_shift=100, velocity_bins=32, dtype=<class 'int'>)[source]
Encode a Music object into event-based representation.
The event-based represetantion represents music as a sequence of events, including note-on, note-off, time-shift and velocity events. The output shape is M x 1, where M is the number of events. The values encode the events. The default configuration uses 0-127 to encode note-on events, 128-255 for note-off events, 256-355 for time-shift events, and 356 to 387 for velocity events.
- Parameters
music (
muspy.Music
) – Music object to encode.use_single_note_off_event (bool, default: False) – Whether to use a single note-off event for all the pitches. If True, the note-off event will close all active notes, which can lead to lossy conversion for polyphonic music.
use_end_of_sequence_event (bool, default: False) – Whether to append an end-of-sequence event to the encoded sequence.
encode_velocity (bool, default: False) – Whether to encode velocities.
force_velocity_event (bool, default: True) – Whether to add a velocity event before every note-on event. If False, velocity events are only used when the note velocity is changed (i.e., different from the previous one).
max_time_shift (int, default: 100) – Maximum time shift (in ticks) to be encoded as an separate event. Time shifts larger than max_time_shift will be decomposed into two or more time-shift events.
velocity_bins (int, default: 32) – Number of velocity bins to use.
dtype (np.dtype, type or str, default: int) – Data type of the return array.
- Returns
Encoded array in event-based representation.
- Return type
ndarray, shape=(?, 1)
- muspy.from_event_representation(array, resolution=24, program=0, is_drum=False, use_single_note_off_event=False, use_end_of_sequence_event=False, max_time_shift=100, velocity_bins=32, default_velocity=64, duplicate_note_mode='fifo')[source]
Decode event-based representation into a Music object.
- Parameters
array (ndarray) – Array in event-based representation to decode.
resolution (int, default: muspy.DEFAULT_RESOLUTION (24)) – Time steps per quarter note.
program (int, default: 0 (Acoustic Grand Piano)) – Program number, according to General MIDI specification [1]. Valid values are 0 to 127.
is_drum (bool, default: False) – Whether it is a percussion track.
use_single_note_off_event (bool, default: False) – Whether to use a single note-off event for all the pitches. If True, a note-off event will close all active notes, which can lead to lossy conversion for polyphonic music.
use_end_of_sequence_event (bool, default: False) – Whether to append an end-of-sequence event to the encoded sequence.
max_time_shift (int, default: 100) – Maximum time shift (in ticks) to be encoded as an separate event. Time shifts larger than max_time_shift will be decomposed into two or more time-shift events.
velocity_bins (int, default: 32) – Number of velocity bins to use.
default_velocity (int, default: muspy.DEFAULT_VELOCITY (64)) – Default velocity value to use when decoding.
duplicate_note_mode ({'fifo', 'lifo', 'all'}, default: 'fifo') –
Policy for dealing with duplicate notes. When a note off event is presetned while there are multiple correspoding note on events that have not yet been closed, we need a policy to decide which note on messages to close. This is only effective when use_single_note_off_event is False.
’fifo’ (first in first out): close the earliest note on
’lifo’ (first in first out): close the latest note on
’all’: close all note on messages
- Returns
Decoded Music object.
- Return type
References
[1] https://www.midi.org/specifications/item/gm-level-1-sound-set
- class muspy.EventRepresentationProcessor(use_single_note_off_event=False, use_end_of_sequence_event=False, encode_velocity=False, force_velocity_event=True, max_time_shift=100, velocity_bins=32, default_velocity=64)[source]
Event-based representation processor.
The event-based represetantion represents music as a sequence of events, including note-on, note-off, time-shift and velocity events. The output shape is M x 1, where M is the number of events. The values encode the events. The default configuration uses 0-127 to encode note-one events, 128-255 for note-off events, 256-355 for time-shift events, and 356 to 387 for velocity events.
- use_single_note_off_event
Whether to use a single note-off event for all the pitches. If True, the note-off event will close all active notes, which can lead to lossy conversion for polyphonic music.
- Type
bool, default: False
- use_end_of_sequence_event
Whether to append an end-of-sequence event to the encoded sequence.
- Type
bool, default: False
- encode_velocity
Whether to encode velocities.
- Type
bool, default: False
- force_velocity_event
Whether to add a velocity event before every note-on event. If False, velocity events are only used when the note velocity is changed (i.e., different from the previous one).
- Type
bool, default: True
- max_time_shift
Maximum time shift (in ticks) to be encoded as an separate event. Time shifts larger than max_time_shift will be decomposed into two or more time-shift events.
- Type
int, default: 100
- velocity_bins
Number of velocity bins to use.
- Type
int, default: 32
- default_velocity
Default velocity value to use when decoding.
- Type
int, default: 64