Database Structure

After downloading or building the database, you’ll end up with an individual directory for each track in the database. The filename is constructed in the form bandleader-trackname-musician1musician2-year-mbzid. Names are given in the format surnamefirstinitial, e.g. Bill Evans would become evansb. In most cases, the bandleader is the pianist, and musician1musician2 are the bassist and drummer, respectively. In cases where another musician was the bandleader, the pianist always takes priority in the ordering of names.

Inside each directory are the following files:

• *_onset.csv files: contain the raw onsets for piano, bass, and drums, with one onset per line;

• beats.csv: contain the onsets matched to each beat, as well as the estimated metre and downbeats, with one beat per line;

• piano_midi.mid: contains the automatically transcribed piano midi;

• metadata.json: contains (surprisingly) track and recording metadata.

Recording metadata

The metadata files contain the following fields for every recording:

Field	Type	Description
track_name	str	Title of the recording
album_name	str	Title of the earliest album released that contains the track
in_30_corpus	bool	Whether the track is in smaller JTD-300 subset of the data
recording_year	int	Year of recording
channel_overrides	dict	Key-value pairs relating to panning: piano: l means the piano is panned to the left channel
mbz_id	str	Unique ID assigned to the track on MusicBrainz
time_signature	int	The number of quarter note beats per measure for the track
first_downbeat	int	The first clear quarter note downbeat in the track
rating_audio	int	Subjective rating (1–3, 3 = best) of source-separation quality
rating_detection	int	Subjective rating of onset detection quality
links	dict	YouTube URL for the recording
excerpt_duration	str	Duration of recording, in Minutes:Seconds format
timestamps	dict	Start and end timestamps for the piano solo in the recording
musicians	dict	Key-value pairs of the musicians included in the recording
fname	str	Audio filename