Jazzify

This is an open-source rule-based jazzification system. Given a melody track and a chord track, Jazzify is able to transfer it into swing jazz style or bossa nova style.

Jazzify is rule-based. Apart from its capability to jazzify non-jazz piece, it can also serve as an engine of computational jazz music theory. Jazzify is able to accomplish tasks including chord-symbol identification, key detection, chord extension, chord-to-scale, chord-to-voicing, walking-bass generation.

As a bonus, Jazzify provides a swingified and a bossaified version of Nottingham Dataset. Jazzify takes the input in muspy's format (json). The swingified Nottingham Dataset is saved in nottingham_swingified.zip, and the bossaified Nottingham Dataset is saved in nottingham_bossaified.zip..

Run the Code

1. Unzip the muspy-formatted Nottingham Dataset in the data directory
2. python jazzify_nottingham.py [out_dir] [style], where [style] chosen from "swing" and "bossa".

Features

Chord Symbol Identification

Jazzify is able to convert list of pitches into its corresponding jazz chord symbol, in format "(root_note, chord_type, bass_note)". Our system is more accurate and faster than music21.

A comprehensive comparison between our system and existing chord symbol identification wheels can be found in 1-chord_test.ipynb.

Key Detection

Jazzify is able to give the (function, key) guesses for each chord, given a chord progression. For example, given chord progression [C, D, F, G, G-, C7, F], Jazzify is able to output [(T,C), (DD,C), (S,C), (D,C), (S,F), (D,F), (T,F)].

Jazzify takes acccout of tonic (T), dominant (D), subdominant (S), double-dominant (DD), Napoleon (N) functions. Other functions like the leading seventh can be converted into the existing categories.

Users are free to give feedbacks on this system. It is not complete, in terms of classical harmony analysis. However, it is powerful enough to handle most jazz standards.

A set of examples of key detection can be found in 2-key_finding_test.ipynb. A lot of chord progressions in jazz standards are incorporated as examples.

Comping and Melody Swingification

Jazzify is able to generate walking bass, piano rootless voicing comping based on the given chord progression. Details are introduced in the documents. The chord-symbol identification and key detection systems are the building blocks of this comping system.

Moreover, Jazzify is able to swingify melody. Combining those systems, Jazzify is able to swingify the pieces in Nottingham Dataset.

Json Format

Input piece should in dictionary format

{
	"metadata": {
		"title": str,
		...
	}

	"tracks": [
	{
		"notes": [{"time":int, "duration":int, "pitch":int}],
		"chords": [{"time":int, "duration":int, "pitches":int}],
	}]
	"time_signatures": [
		{"time":int, "numinator":int, "denominator":int}
	]
	"tempos": [
		{"time":int, "qpm":float}
	]
	...
}

The json files in Nottingham Swingified/Bossaified are in format

{
	"metadata": {
		"title": str,
	}

	"tracks": [
	{
		"notes": [{"time":int, "duration":int, "pitch":int}],
		"voicings": [{"time":int, "duration":int, "pitches":int}],
		"basses": [{"time":int, "duration":int, "pitch":int}],
	}]
	"time_signatures": [
		{"time":int, "numinator":int, "denominator":int}
	]
	"tempos": [
		{"time":int, "qpm":float}
	]
	"chord_symbols": [
		(root:int, symbol:str, bass:int/None)
	]
	...
}