This project aims to create a nice audio visualisation using Web Audio API and, after that, control an arduino board attached to the computer and show its result at the background color. It's a very nice work to turn music into dancing leds! It is made of two parts: Aria and Lumen, explained later.
Anyone can easily execute this by simply downloading and running inside its root directory:
node server.js
Its results:
This execution starts a server. Now, just simply open your browser and locahost:3000 it.
This is the browser part. When the server says it's okay to start listening (after connectirng an arduino board through USB), Aria asks for permission to use the microphone. After that, it listen the audio stream and connect this to a analyser node, which provides a nice FFT implementation. Using this feature, it's possible to divide audio in frequency bands, allowing us to assign a band or a combination of them to a color. The default implementation tells the browser to change <body> background color property to a RGB value where R is the bass, G is the mid frequencies and B is all the treble. Finally, this result is continuously sent to Lumen.
It lives inside the server, searching for an arduino board. When it's ready, it tells Aria that it's okay to start listening. So, it waits until Aria sends any sample, which means a simple combination of RGB. After that, it controls the arduino to power on three pins according to the sample received (by default: red pin is 8, green pin is 9, blue pin is 10).
