instrument

The Instrument class holds all events for a single instrument and contains functions for extracting information from the events it contains.

class pretty_midi.instrument.Instrument(program, is_drum=False, name='')

Object to hold event information for a single instrument.

Parameters:

programint

MIDI program number (instrument index), in [0, 127].

is_drumbool

Is the instrument a drum instrument (channel 9)?

namestr

Name of the instrument.

Attributes:

programint

The program number of this instrument.

is_drumbool

Is the instrument a drum instrument (channel 9)?

namestr

Name of the instrument.

noteslist

List of pretty_midi.Note objects.

pitch_bendslist

List of of pretty_midi.PitchBend objects.

control_changeslist

List of pretty_midi.ControlChange objects.

__init__(program, is_drum=False, name='')

Create the Instrument.

get_onsets()

Get all onsets of all notes played by this instrument. May contain duplicates.

Returns:

onsetsnp.ndarray

List of all note onsets.

get_piano_roll(fs=100, times=None, pedal_threshold=64)

Compute a piano roll matrix of this instrument.

Parameters:

fsint

Sampling frequency of the columns, i.e. each column is spaced apart by 1./fs seconds.

timesnp.ndarray

Times of the start of each column in the piano roll. Default None which is np.arange(0, get_end_time(), 1./fs).

pedal_thresholdint

Value of control change 64 (sustain pedal) message that is less than this value is reflected as pedal-off. Pedals will be reflected as elongation of notes in the piano roll. If None, then CC64 message is ignored. Default is 64.

Returns:

piano_rollnp.ndarray, shape=(128,times.shape[0])

Piano roll of this instrument.

get_chroma(fs=100, times=None, pedal_threshold=64)

Get a sequence of chroma vectors from this instrument.

Parameters:

fsint

Sampling frequency of the columns, i.e. each column is spaced apart by 1./fs seconds.

timesnp.ndarray

Times of the start of each column in the piano roll. Default None which is np.arange(0, get_end_time(), 1./fs).

pedal_thresholdint

Value of control change 64 (sustain pedal) message that is less than this value is reflected as pedal-off. Pedals will be reflected as elongation of notes in the piano roll. If None, then CC64 message is ignored. Default is 64.

Returns:

piano_rollnp.ndarray, shape=(12,times.shape[0])

Chromagram of this instrument.

get_end_time()

Returns the time of the end of the events in this instrument.

Returns:

end_timefloat

Time, in seconds, of the last event.

get_pitch_class_histogram(use_duration=False, use_velocity=False, normalize=False)

Computes the frequency of pitch classes of this instrument, optionally weighted by their durations or velocities.

Parameters:

use_durationbool

Weight frequency by note duration.

use_velocitybool

Weight frequency by note velocity.

normalizebool

Normalizes the histogram such that the sum of bin values is 1.

Returns:

histogramnp.ndarray, shape=(12,)

Histogram of pitch classes given current instrument, optionally weighted by their durations or velocities.

get_pitch_class_transition_matrix(normalize=False, time_thresh=0.05)

Computes the pitch class transition matrix of this instrument. Transitions are added whenever the end of a note is within time_tresh from the start of any other note.

Parameters:

normalizebool

Normalize transition matrix such that matrix sum equals to 1.

time_threshfloat

Maximum temporal threshold, in seconds, between the start of a note and end time of any other note for a transition to be added.

Returns:

transition_matrixnp.ndarray, shape=(12,12)

Pitch class transition matrix.

remove_invalid_notes()

Removes any notes whose end time is before or at their start time.

synthesize(fs=44100, wave=<ufunc 'sin'>)

Synthesize the instrument’s notes using some waveshape. For drum instruments, returns zeros.

Parameters:

fsint

Sampling rate of the synthesized audio signal.

wavefunction

Function which returns a periodic waveform, e.g. np.sin, scipy.signal.square, etc.

Returns:

synthesizednp.ndarray

Waveform of the instrument’s notes, synthesized at fs.

fluidsynth(fs=None, synthesizer=None, sfid=0, sf2_path=None)

Synthesize using fluidsynth.

Parameters:

fsint

Sampling rate to synthesize at. Default None, which takes the sampling rate from synthesizer, or uses pretty_midi.fluidsynth.DEFAULT_SAMPLE_RATE = 44100 if a synthesizer needs to be created.

synthesizerfluidsynth.Synth or str

fluidsynth.Synth instance to use or a string with the path to a .sf2 file. Default None, which creates a new instance using the TimGM6mb.sf2 file included with pretty_midi.

sfidint

Soundfont ID to use if an instance of fluidsynth.Synth is provided. Default 0, which uses the first soundfont.

sf2_pathstr

Path to a .sf2 file. Default None, which uses the TimGM6mb.sf2 file included with pretty_midi. .. deprecated:: 0.2.11

Use :param:`synthesizer` instead.

Returns:

synthesizednp.ndarray

Waveform of the MIDI data, synthesized at fs.