Best way to resize?

[Garfield9]

Hi, this is a just question not an issue. I want to edit some 1080p footage together with some 480p footage in Resolve. I noticed that in the timeline sometimes the 480p video looks a little pixelated at times. So I thought that maybe I should resize it to 1080p so that wouldn't happen. I researched a little bit and everyone recommended NNEDI3 as the best resizer and since Hybrid has it I tried it. I tried the Vapoursynth and Avisynth versions and they work fine it makes the video a little sharper too I think. But I was just wondering if my research was right and wanted to ask myself if it really is the best because I still see a few pixels when I zoom in and a few tiny details seemed to not be there anymore.

[Selur]

There is no 'best way'. Just asking that question kind of disqualifies you.

Some other resizers might also be worth looking at. -> Use the preview and decide what looks best for your content.

In general NNEDI3 is a good resizer for natural clean content.
When going from SD to HD or hichter using stepped resizing combined with some denoising or sharpening also might help to improve things.
Also note that tweaking the NNEDI3 setting on it's own also might improve the result.

Cu Selur

Ps.: adding some contrast sharpening might also help.

[Garfield9]

Thanks for that info. What do you mean disqualifies me? I never claimed that I am a pro or doing this as a job, just a hobby I got and am still learning.

[Selur]

Usually there is no general best way, since anything that changes the content will change how 'good' or 'bad' one will perceive it and that perception in the end is always subjective. So there is no way for others to answer that question in any meaningful way and still asking for the best way simply shows that you haven't spend some time thinking about what you are asking.

If the goal is to keep the original pixels as untouched as possible, using point resizing would be recommendet, but unless your source is pixel art (old 8bit content or similar) usually folks do not prefer point resizing.

Cu Selur

[Garfield9]

That makes sense. I want to resize 480p Dragon Ball Z video and mix it with some 1080p also Dragon Ball Z video. So its old anime shot on film with grain. So I want to resize it with all the pixels as untouched as possible like you said before so I would want point resizing. Now excuse me for being a noob but what exactly do you mean by point resizing? You mean PointResize in Avisynth?

[Selur]

So I want to resize it with all the pixels as untouched as possible l

I doubt that is really what you want.

But to use point resize do the following:

• Start Hybrid
  
• Load your source
  
• Enable "Crop/Resize->Base->Resize"
  
• Set "Crop/Resize->Base->Resize->Picture resize->Auto adjust" to "width"
  
• Set "Crop/Resize->Base->Resize->Picture resize->Target resolution" height to 1080
  
• Enable "Filtering->Frame->Resize->Resizer"
  
• Set "Filtering->Frame->Resize->Resizer" to 'fmtconv'
  
• Set "Filtering->Frame->Resize->Resizer->Resizer" to 'point'
  
• Enable "Filtering->Vapoursynth->Misc->Preview->Split View"
  
• Open the Vapoursynth Preview (Filtering->Vapoursynth Preview"
  
• Enable "Filtering->Synth auto refresh"
  
• Enable "Filtering->Filterview"
  

this way you can see the difference between 'bicubic' and 'point' resize in the preview.
(Resizer on the left side is specified by 'Filtering->Vapoursynth->Misc->Preview->Compensate resize'.)

That said, most folks that want to resize cartoon/anime content from SD to HD prefer one of the following:

• NNEDI3 + stepped resize and aWarpSharp as resizer
  
• Waifu2x or Waifu2x nvk
  
• Anime4kCP
  
• VSGAN+ BSRGAN or DigitalFrames*
  
• RealESRGAN*
  

* (requires torchAddon and a NVIDIA card)
So you might want to keep the preview open and go to 'Filtering->Frame->Resizer' and check how the output changes when you switch to different resizers.

Cu Selur

[Garfield9]

Oh yeah that is pixelated as hell haha nvm then! Thanks for the explenation. Out of the options you listed I think NNEDI3 with stepped and aWarpSharp looks good. I used the VS version and in the stepped section it doesnt give any explenation as to what those settings do. So should I just use 2 steps and aWarpSharp2(depth=5)? Also does setting crf to 1 which is the minimum make the result lossless?

[Selur]

Stepped resize, does the resizing in steps. (best look at the Vapoursynth script view to see that it does)
So instead of directly resizing to the target resolution it resized to a resolution in the middle and then to the target resolution and additionally can apply denoising and sharpening.

Yes, I think that using that more steps than 2 when resizing from SD to HD is overkill.
I can't say whether this is the best setting for you since I have no clue what you like.

About the lossless encoding:
No, to use lossless encoding (= huge output size) you need to use 'constant quantizer (1-pass)', set the restriction setitngs to a profile&level which allows lossless encoding. set "Quantization strength" to 0 and enabled 'Lossless'. (or similar, since you didn't say what format you want encoder you use)

Cu Selur

[Garfield9]

Ok I want to encode with x264 and I can only pick lossless with profile high4:4:4 and none. I can't set it to 0 the least I can set it is 1 although once I choose lossless the quantization strength gets greyed out so I guess it doesn't matter once you pick lossless. Also I know the size is huge but I plan to use the resulting file only temporarily for the edit.
 As for denoising and sharpening I don't want to denoise I want all the grain to remain and as for sharpening I tried aWarpSharp2 and it looks really good, I just want to make sure that I can use sharpening without it creating artifacts or losing details. As far as I can tell aWS doesn't do that though and it reduces those dark shadows around the lines which I think are there due to the low resolution.

[Selur]

Ok I want to encode with x264 and I can only pick lossless with profile high4:4:4 and none.

That is correct, see: https://en.wikipedia.org/wiki/Advanced_V...r_profiles
Ah sorry, just checked and I removed the 0, but enabling lossless is enough, command line will include '-qp 0'.

As for denoising and sharpening I don't want to denoise I want all the grain to remain and as for sharpening I tried aWarpSharp2 and it looks really good, I just want to make sure that I can use sharpening without it creating artifacts or losing details. As far as I can tell aWS doesn't do that though and it reduces those dark shadows around the lines which I think are there due to the low resolution.

Then simply don't use stepped resize and sharpening.
Any filtering will cause some sort of change that could be understood as artifact.

Going to bed now, but your best choice is probably to look at the resizers and use the one that best fits to what you want.

Cu Selur