Piano-roll Representation¶

muspy.to_pianoroll_representation(music: Music, encode_velocity: bool = True, dtype: Union[numpy.dtype, type, str] = None) → numpy.ndarray[source]

Encode notes into piano-roll representation.

Parameters:	music (`muspy.Music`) – Music object to encode. encode_velocity (bool, default: True) – Whether to encode velocities. If True, a binary-valued array will be return. Otherwise, an integer array will be return. dtype (np.dtype, type or str, optional) – Data type of the return array. Defaults to uint8 if encode_velocity is True, otherwise bool.
Returns:	Encoded array in piano-roll representation.
Return type:	ndarray, shape=(?, 128)

muspy.from_pianoroll_representation(array: numpy.ndarray, resolution: int = 24, program: int = 0, is_drum: bool = False, encode_velocity: bool = True, default_velocity: int = 64) → muspy.music.Music[source]

Decode piano-roll representation into a Music object.

Parameters:	array (ndarray) – Array in piano-roll 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. encode_velocity (bool, default: True) – Whether to encode velocities. default_velocity (int, default: muspy.DEFAULT_VELOCITY (64)) – Default velocity value to use when decoding. Only used when encode_velocity is True.
Returns:	Decoded Music object.
Return type:	`muspy.Music`

References

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

class muspy.PianoRollRepresentationProcessor(encode_velocity: bool = True, default_velocity: int = 64)[source]

Piano-roll representation processor.

The piano-roll represetantion represents music as a time-pitch matrix, where the columns are the time steps and the rows are the pitches. The values indicate the presence of pitches at different time steps. The output shape is T x 128, where T is the number of time steps.

encode_velocity¶

Whether to encode velocities. If True, a binary-valued array will be return. Otherwise, an integer array will be return.

Type:	bool, default: True

default_velocity¶

Default velocity value to use when decoding if encode_velocity is False.

Type:	int, default: 64

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

Decode piano-roll representation into a Music object.

Parameters:	array (ndarray) – Array in piano-roll representation to decode. Cast to integer if not of integer type. If encode_velocity is True, casted to boolean if not of boolean type.
Returns:	Decoded Music object.
Return type:	`muspy.Music` object