In the piano roll, the length of each note event in the display directly ... Whether a given note is deemed sharp or flat largely depends on the current scale or key. On the piano keyboard, two notes ...

Perforated rolls of paper, called piano rolls ... that one pixel corresponded with one key. With that done, each column could be assigned to a specific note on the piano. That takes care of ...

He plays silent chords on the keyboard, like a remote control of sorts, then the chords are run through the software, and the piano plays a spontaneous array of notes based on the Euclidean algorithm.