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via

The FCEUX “Music PulseWave” Lua script, running on top of the ROM flyer for a November 2007 PulseWave concert in NYC.

The script turns the non-interactive ROM into a rhythm game. The program automatically analyzes the music, displaying each of the NES’s four audio channels as a bar at the top of the screen. I don’t really understand the interface or the scoring, but the gameplay is as simple as pressing the A button to the beat of the song. It apparently works for other games too — here’s Music PulseWave on top of Journey to Silius.

And UI found the intial thread with the source:

For the intrigued:

Main Lua file
Required Lua file

FCEUX
Lua pack, to be extracted in FCEUX’s directory

The ROM

Basically, open ROM, hit “Run Lua script…” and pick music_pulsewave.lua, then go.