Q: Video Effect: Spectrum Analyzer - How to add Slope & Smoothing

[RCJacH]

Edit: Moved to Video section as I just realized Video Processor is not a JSFX.



I'm trying to add spectrum analysis to a video, and found out the awesome preset "Synthesis: Decorative Spectrum Analyzer (requires JSFX video sample peeker)".

To make video looks nicer, I would like to expand the rendered look of the spectrum output display. The problem is that, being terrible at math, 150 lines of undocumented dsp goes through my head like air. Thus I come here for help.

The question is, is there a simple way to add Slope and Smoothing/Intergrate parameter to the preset? Or did anyone already modified this preset for such purpose? As an example, both parameters can be found in sai'ke's stunning and wonderful Spectral Analyzer(s).

An alternative method to approach this is to insert a JSFX prior to video sample peeker that averages the input signal being sent to the video processor, but again being a total noob in dsp, I did not really understand how to do so.

[X-Raym]

Indeed, more options too this effects could be quite interesting, cause it really adjust fast.

But too limited for now for being used IMHO.

[ashcat_lt]

The spectrum analyzer preset does all the FFT stuff on that end. Anything you do to the audio before the sample peeker to try to smooth the response will just mess up the spectrum itself. That is, most of the things we would do would be a whole lot like low-pass filtering, and you’d see that loss of high frequencies on the other end. It will work for the oscilloscope and other things that respond to actual individual sample values, but for the spectrum analyzer, you’re gonna have to figure out how to smooth the display after the analysis happens. I’m sure it could be done. Maybe look at sa’ike’s code and see how they managed it.