Orpheus

Node experiment for training an online classification model to learn individual music tastes using user feedback to 30-second Spotify previews.

Installation

Clone this repo

git clone https://github.com/shunr/orpheus.git
cd code-curator

Install dependencies

npm install

Orpheus uses @ikegami-yukino's python implementation of OLL

pip install -r requirements.txt

Create configuration file

cp config.example.json config.json

Usage

npm start

Configuration

Configuration is done through the objects found in /config.json

config.spotify

Option	Description
clientId	Client id used to access Spotify API
clientSecret	Client secret used to authenticate with Spotify API

config.db

Option	Description
firstInitialization	Orpheus generates a database of song metadata retrieved from Spotify to overcome rate limits. Required to be true on the first time running Orpheus, then should be set to false to improve startup speed.
storagePath	Path to persistent JSON database
modelDirectory	Directory used to store classification models for each user session

config.tracks

Option	Description
minPopularity	Integer from 1 to 100 representing minimum popularity of a song to be used as a training case.
tracksPerGenre	Integer from 1 to 100 of tracks to fetch per genre. A higher number is recommended for accurate training results but will take longer to initialize
maxQueuedTracks	Maximum number of tracks to play to a user
ignoredGenres	Array of genre names to not include on initialization

config.hyperParams

These represent training hyperparameters used by the oll library. Tweak for possibly better results. CW should be optimal.

Features

Features need to be normalized from the data retrieved from Spotify API.

Good feature scaling

Optimization cab be done with feature objects in /feature_mapping.json. Generally, mean values should correspond to zero. For example, while loudness can range for -60 to 0 dB, the mean value is -8 and the feature should be normalized with this in mind.

Example feature

"loudness": {
  "min": -16,
  "max": 0,
  "key": 5,
  "icon": "volume up",
  "extremes": [
    "quiet",
    "loud"
  ]
}