[HELP] Remove Rainbowing

[RetroHelix]

I used Hybrid for de-interlacing and also did some color conversion with the following settings:



Now I was wondering if I can pimp the output a bit and tried to remove rainbow effects (see the lapel of the right guy and the necktie (green at the end of the screen) of the left guy) but was not able to get a good output:

The effect is even stronger than in the original :\

I tried some suggestions from here (link) but Hqdn3d and/or Degraining was not helping. Honestly I feel a bit lost. I'm just too dumb to alter the parameters of the filters in a meaningful way.

In the original Video you can see heavy rainbowing in the beginning and at 1:30.

Would be nice if someone is able to help me with this. Can this even be removed?


Thank you

[Selur]

If using the vs-mlrt add-on is an option using 1x_BleedOut_Compact_300k_net_g followed by LUTDeRainbow (with chroma threshold = 15). (the order of the filters is important)
I will also try to find a solution without vs-mrt.
LUTDeRainbow with cthresh=20, ythresh=20 + FixChromaBleedingMod(clip, cx=6, cy=6, strength=1.50) does seem to do the job as well and does not tes require vs-mlrt add-on.

Cu Selur

[RetroHelix]

Wow, thank you for the ultra fast reply.

I set LUTDeRainbow and FixChromaBleeding inside Hybrid to the values you posted:



While it seems to be a bit better its still quite noticeable.


Am I missing something?

[Selur]

Your screenshots of the settings are useless (at least to me).
Better either post your script (Vapoursynth Script View) or a debug output. (the script would show me if you use other filters additionally which might influence the effect of the suggested filtering)


is what it looks to me. (unlike you, I didn't disable 'Link UV')
using 1x_BleedOut_Compact_300k_net_g does provide better results here, using 5694 (of the bobbed sample):


If you make screenshots of the content, use the option in vsViewer and also post the frame number that refers to the clip you shared, so I can compare it without having to search for it,..


Cu Selur


Ps.: just thought about boosting the saturation after the rainbowing, for testing how well it worked => looking some more at it

[RetroHelix]

Your screenshots of the settings are useless (at least to me).
Better either post your script (Vapoursynth Script View) or a debug output.

I see. I didn't know that. Here you go: script

is what it looks to me. (unlike you, I didn't disable 'Link UV')

Here is Frame 5675 (almost the same you posted) with Link UV enabled:

using 1x_BleedOut_Compact_300k_net_g  does provide better results here, using 5694 (of the bobbed sample):

I'll try to get this up and running.

[Selur]

try:
DeCross wiht thresholdy:1, noise: 80, margin: 2
+
KNLMeansCL channels: UV, strength: 5
Here is Frame 5674:

with boosting the Saturation after this one can see there is still some left:

...
Increasing the search radius of KNLMeans to 6 helps further and adding LUTDeRainbow before KNLMeans additionally removes more adding SmallDeflcker(agressive with cnr enabled) additionally helps.

Cu Selur

Ps.: Here's a encode I made using: https://pastebin.com/WYYb7kuq

[RetroHelix]

Wow, thank you very much. I set DeCross and KNLMeanCL and LUTDeRainbow + SmallDeflicker accordingly and it worked really well. I also got vs-mlrt working and by using everything together and now there seems to be no rainbow effect anymore

So in the end I don't understood/understand all the settings good enough to make the filters work correctly...

PS. I read that I should use the color matrix filter when trying to upscale the video later on, via seedvr or Topazai. But setting the matrix from Rec.601 to Rec.709 will slightly change the image to a darker tone. Do you know of any way to prevent this?

EDIT: In the end I'm not using vs-mlrt because with the other filters it already looks great.

[Selur]

When changing the matrix, you should make sure the output format also supports vui matrix signaling and the signaling is correct.
Whether changing the matrix makes sense depends on how the tool you supports vui matrix signaling.
For example some tools will always assume bt601 when fed with SD and 709 when fed with higher resolution content. So if you change the color values to represent the i.e. 709 for SD content, those tools will not handle the colors properly.

Cu Selur

[RetroHelix]

All right, I'll keep that in mind