Event-based Representation¶

muspy.to_event_representation(music: Music, use_single_note_off_event: bool = False, use_end_of_sequence_event: bool = False, encode_velocity: bool = False, force_velocity_event: bool = True, max_time_shift: int = 100, velocity_bins: int = 32, dtype=<class 'int'>) → numpy.ndarray[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: numpy.ndarray, resolution: int = 24, program: int = 0, is_drum: bool = False, use_single_note_off_event: bool = False, use_end_of_sequence_event: bool = False, max_time_shift: int = 100, velocity_bins: int = 32, default_velocity: int = 64, duplicate_note_mode: str = 'fifo') → muspy.music.Music[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:	`muspy.Music`

References

[1] https://www.midi.org/specifications/item/gm-level-1-sound-set

class muspy.EventRepresentationProcessor(use_single_note_off_event: bool = False, use_end_of_sequence_event: bool = False, encode_velocity: bool = False, force_velocity_event: bool = True, max_time_shift: int = 100, velocity_bins: int = 32, default_velocity: int = 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

decode(array: numpy.ndarray) → muspy.music.Music[source]

Decode event-based representation into a Music object.

Parameters:	array (ndarray) – Array in event-based representation to decode. Cast to integer if not of integer type.
Returns:	Decoded Music object.
Return type:	`muspy.Music` object