BlueCyro / FastFourierFun

Lets you create FFT datasets for static audio clips in Neos

Fast fourier fun

DISCLAIMER: This is a work in progress. It is not yet ready for production use. Any and all implemention of features by this mod are subject to change at any time without warning.

That being said; this is a NeosModLoader mod that lets you get FFT values out of an audio clip.

Installation

Make sure NeosModLoader is installed and just drop the latest release into the nml_mods folder.

Usage

• Simply grab a StaticAudioClip or imported audio clip with the LogiX tip and hit the "Get FFT" button on your context menu.
• You will be presented with four buttons. The top left most one is to set the bin size.
• The top right will increase the read frequency (may help with slowly updating FFT due to large bin sizes)
• The bottom left will of course get the FFT
• The botton right will slice (throw away) any FFT slice past what is represented on the button.
• It will take a little while to compute the FFT, but once it's done you will receive an item with an animation clip on it. Each track on the clip is a value from the FFT in ascending order.
• In logix, you may then sample the FFT by sampling the animation clip at a given position for the sound you ran through it
• Each track is a slice of the FFT represented as a float. (If you're making visualizers, I recommend multiplying the amplitude by log10 or so as you for loop through the tracks)

Notes

• Note that for now the FFT result is the maximum amplitude of the results. (E.g. 2 channels - per FFT slice, the result is the maximum of the channels' amplitudes.)
• The FFT is also represented as an absolute value, so you're not gonna get any negatives in there.
• I'd also recommend getting the absolute value of the FFT result anyways, as this may very well change in the future.

Limitations

• This mod won't let you get FFT from a video file, it has to be a format that supports native playback. (ogg, flac, wav, etc.)
• This mod will not work on audio streams.
• Please don't use an animator to play the clip, it will be very laggy. I recommend only sampling it with LogiX.

For mod developers

• This mod implements an extension to AudioX datatypes so you can simply call:
• AudioX.GetFFTAnimation(int FFTBucketSize) to get the FFT animation clip. (This must be a power of 2)
• I highly recommend using this function in an asynchronous manner, as it will take a while to compute the FFT.
• Same goes for actually writing it into a StaticAnimationProvider, that takes the longest.

 

• This mod was developed in vscode, not visual studio as most other mods are.