At HackWSU, I built a website that takes in three user-inputted songs, and determines the overall "tone" of the three songs. It breaks these tones down into 5 categories- anger, sadness, fear, jealousy and joy. It then takes these tones and converts them into colors. The colors are shown as a gradient on the background, and can be downloaded to start a project for artists.
This was done using IBM Watson's tone analyzer API and musixmatch's lyric API.