(issue, possibly??) noise is too dark in highlights

[nlolnlolnlolnlo]

i feel like the way noise is handled in light areas in ntsc-rs could use some work. usually on analog video transfers, the light portions of the image aren't as affected by noise as more median colors. my stupid guess is that the light areas likely don't have the bandwith to get any darker or lighter in the way that neutral tones do. (this is also probably slightly visible in dark areas but it's not as visible.)

could some falloff be added to the way noise is handled or something? this is one of the only things that i think is holding ntsc-rs back from being nearly indistinguishable from real vhs/cvbs at this point.

ntsc-rs (noise slightly boosted for visibility)

real vhs

[valadaptive]

At first I wondered if this was some sort of gamma issue, but it seems like YIQ is gamma-corrected in the way I'm currently doing it.

Can you share the test image and preset you're using here?

[nlolnlolnlolnlo]

ntsc-rs_vhs-sp_v8_noiseboosted.json

[valadaptive]

It may just be that the noise is more visible in the highlighted areas for perceptual reasons. I think some of it comes from the "Composite noise" being lower-frequency than the luma noise visible in the VHS tape transfer, and hence more visible.

I've added a "Luma noise" setting in version 0.7.0, and got this result (here's the preset):

I think it looks similar to the VHS tape transfer, although a bit brighter. Try it out and let me know if it works for you.

[nlolnlolnlolnlo]

the new noise options are very good, but i'm still of the opinion that an option to clip the noise at the bright areas would be a bit more accurate looking.

i've attached some comparisons with large areas of white below:

and the clean graphics for both. the comparisons used the preset that you posted above so it's not included.