IIDX Green Number Calculator

This is a tool to convert your HI-SPEED into Green Number, so you can continue playing IIDX at your preferred speed, even when Green Number didn't exist yet. Tested on 8th Style, 10th Style, IIDX RED, Distorted, and EMPRESS (with GN enabled, to make sure it's accurate), all on actual PS2 hardware. It works perfectly on IIDX RED and later, even down to the frame. On 10th Style and before, it seems…