Piano-roll Representation

muspy.to_pianoroll_representation(music, encode_velocity=True, dtype=None)[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, resolution=24, program=0, is_drum=False, encode_velocity=True, default_velocity=64)[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=True, default_velocity=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