Is this anime noise?

[PurpleKnight]

I've been using noise reduction scripts and I couldn't improve the image to much, maybe I need to use a heavy denoiser or adjust some settings. I even thought this was some kind of dithering or banding.
I would greatly appreciate any advice.

https://i.slow.pics/1WwS49xh.png

https://i.slow.pics/QvdUoO7C.png

Related link (https://slow.pics/c/kNPcZ0gy)

[ChaosKing]

I don't really see any noise. But banding and some light compression artifacts and maybe some halos.
Try f3kdb / neo f3kdb

[Macross96]

I used the idea behind fag3kdb and ported it to avisynth.
Here's how I wrote it for this occasion
z_ConvertFormat(pixel_type="YUV444P16",resample_filter_uv="spline36",dither_type="none")

masking = ConvertToStacked().GradFun3(thr=0.8, thrC=0.5, smode=3, lsb_in=true, lsb=true, debug=1)
\ .ConvertFromStacked()

filtered= neo_f3kdb(range=31, grainY=45, grainC=45, blur_first=true,
\ dynamic_grain=false, keep_tv_range=true)

mt_merge(filtered, last, masking, Y=3, U=3, V=3).ConvertToStacked()

DitherPost()

(Note: source is yv12)

The results are nice (and are improveable)... yet, I really don't know what to do about the light compression artifacts (and haven't find something significantly helpfulf)

https://i.slow.pics/WmHaRGbY.png

https://i.slow.pics/OMPcKCLI.png