Utils methods

You will also find some useful methods.

miditok.utils.detect_chords(notes: List[Note], time_division: int, beat_res: int = 4, onset_offset: int = 1, only_known_chord: bool = False, simul_notes_limit: int = 20) → List[Event]

Chord detection method. Make sure to sort notes by start time then pitch before: notes.sort(key=lambda x: (x.start, x.pitch)). On very large tracks with high note density this method can be very slow. If you plan to use it with the Maestro or GiantMIDI datasets, it can take up to hundreds of seconds per MIDI depending on your cpu. One time step at a time, it will analyse the notes played together and detect possible chords.

Parameters:

  • notes – notes to analyse (sorted by starting time, them pitch)

  • time_division – MIDI time division / resolution, in ticks/beat (of the MIDI being parsed)

  • beat_res – beat resolution, i.e. nb of samples per beat (default 4)

  • onset_offset – maximum offset (in samples) ∈ N separating notes starts to consider them starting at the same time / onset (default is 1)

  • only_known_chord – will select only known chords. If set to False, non recognized chords of n notes will give a chord_n event (default False)

  • simul_notes_limit – nb of simultaneous notes being processed when looking for a chord this parameter allows to speed up the chord detection (default 20)

Returns:

the detected chords as Event objects

miditok.utils.get_midi_programs(midi: MidiFile) → List[Tuple[int, bool]]

Returns the list of programs of the tracks of a MIDI, deeping the same order. It returns it as a list of tuples (program, is_drum).

Parameters:

midi – the MIDI object to extract tracks programs

Returns:

the list of track programs, as a list of tuples (program, is_drum)

miditok.utils.merge_same_program_tracks(tracks: List[Instrument])

Takes a list of tracks and merge the ones with the same programs. NOTE: Control change messages are not considered

Parameters:

tracks – list of tracks

miditok.utils.merge_tracks(tracks: Union[List[Instrument], MidiFile], effects: bool = False) → Instrument

Merge several miditoolkit Instrument objects, from a list of Instruments or a MidiFile object. All the tracks will be merged into the first Instrument object (notes concatenated and sorted), beware of giving tracks with the same program (no assessment is performed). The other tracks will be deleted.

Parameters:

  • tracks – list of tracks to merge, or MidiFile object

  • effects – will also merge effects, i.e. control changes, sustain pedals and pitch bends

Returns:

the merged track

miditok.utils.merge_tracks_per_class(midi: MidiFile, classes_to_merge: Optional[List[int]] = None, new_program_per_class: Optional[Dict[int, int]] = None, max_nb_of_tracks_per_inst_class: Optional[Dict[int, int]] = None, valid_programs: Optional[List[int]] = None, filter_pitches: bool = True)

Merges per instrument class the tracks which are in the class in classes_to_merge. Example, a list of tracks / programs [0, 3, 8, 10, 11, 24, 25, 44, 47] will become [0, 8, 24, 25, 40] if classes_to_merge is [0, 1, 5]. The classes are in miditok.constants.INSTRUMENT_CLASSES.

Note: programs of drum tracks will be set to -1.

Parameters:

  • midi – MIDI object to merge tracks

  • classes_to_merge – instrument classes to merge, to give as list of indexes (see miditok.constants.INSTRUMENT_CLASSES). Give None to merge nothing, the function will still remove non-valid programs / tracks if given (default: None)

  • new_program_per_class – new program of the final merged tracks, to be given per instrument class as a dict {class_id: program}

  • max_nb_of_tracks_per_inst_class – max number of tracks per instrument class, if the limit is exceeded for one class only the tracks with the maximum notes will be kept, give None for no limit (default: None)

  • valid_programs – valid program ids to keep, others will be deleted, give None for keep all programs (default None)

  • filter_pitches – after merging, will remove notes whose pitches are out the recommended range defined by the GM2 specs (default: True)

Returns:

True if the MIDI is valid, else False

miditok.utils.nb_bar_pos(seq: List[int], bar_token: int, position_tokens: List[int]) → Tuple[int, int]

Returns the number of bars and the last position of a sequence of tokens. This method is compatible with tokenizations representing time with Bar and Position tokens, such as miditok.REMI.

Parameters:

  • seq – sequence of tokens

  • bar_token – the bar token value

  • position_tokens – position tokens values

Returns:

the current bar, current position within the bar, current pitches played at this position, and if a chord token has been predicted at this position

miditok.utils.remove_duplicated_notes(notes: List[Note])

Removes (inplace) possible duplicated notes, i.e. with the same pitch, starting and ending times. Before running this function make sure the notes has been sorted by start then pitch then end values: notes.sort(key=lambda x: (x.start, x.pitch, x.end))

Parameters:

notes – notes to analyse