Pitch-based Representation

muspy.to_pitch_representation(music, use_hold_state=False, dtype=<class 'int'>)[source]

Encode a Music object into pitch-based representation.

The pitch-based represetantion represents music as a sequence of pitch, rest and (optional) hold tokens. Only monophonic melodies are compatible with this representation. The output shape is T x 1, where T is the number of time steps. The values indicate whether the current time step is a pitch (0-127), a rest (128) or, optionally, a hold (129).

Parameters
  • music (muspy.Music) – Music object to encode.

  • use_hold_state (bool, default: False) – Whether to use a special state for holds.

  • dtype (np.dtype, type or str, default: int) – Data type of the return array.

Returns

Encoded array in pitch-based representation.

Return type

ndarray, shape=(?, 1)

muspy.from_pitch_representation(array, resolution=24, program=0, is_drum=False, use_hold_state=False, default_velocity=64)[source]

Decode pitch-based representation into a Music object.

Parameters
  • array (ndarray) – Array in pitch-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_hold_state (bool, default: False) – Whether to use a special state for holds.

  • default_velocity (int, default: muspy.DEFAULT_VELOCITY (64)) – Default velocity value to use when decoding.

Returns

Decoded Music object.

Return type

muspy.Music

References

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

class muspy.PitchRepresentationProcessor(use_hold_state=False, default_velocity=64)[source]

Pitch-based representation processor.

The pitch-based represetantion represents music as a sequence of pitch, rest and (optional) hold tokens. Only monophonic melodies are compatible with this representation. The output shape is T x 1, where T is the number of time steps. The values indicate whether the current time step is a pitch (0-127), a rest (128) or, optionally, a hold (129).

use_hold_state

Whether to use a special state for holds.

Type

bool, default: False

default_velocity

Default velocity value to use when decoding.

Type

int, default: 64