Is there a way to configure upscaling?

[Ijven 4]

Hi, 

I'm looking to do some upscaling for DVD and VHS recordings, if at all possible, to "prettify" and display on HD or 4K device that has no native upscaling. I did read something about "mpv.conf" file adding this capability but no further reference. 

The Emby server resides on a Linux box with ample compute capacity.

Thanks in advance!

[Luke 42078]

Hi, what Emby client app?

[Ijven 4]

Hi, 

I'm looking to do so server side as I mostly use the LG OS app and browser.  Unless there is a way to let the client side manage this? (if I understand correctly only Nvidea Shield had client upscale capability?)

Kind regards.

[Luke 42078]

So the way Emby apps work is you specify your max quality setting, but that setting is used an upper limit, not a set value. The server will then keep the quality below that as well as below the original. 

So as a result, there is no upscaling when transcoding. That's not to say it's not a possible option down the road, it's just that it doesn't do that today. So your best options will be client devices with upscaling capabilities.

[softworkz 5066]

13 hours ago, Ijven said:

I'm looking to do so server side as I mostly use the LG OS app and browser.  Unless there is a way to let the client side manage this? (if I understand correctly only Nvidea Shield had client upscale capability?)

I don't understand what you are up to.

Are you saying the the LG app is unable to scale a video to the screen size? I.e. - are you saying that when watching a 1080 video on a 4k TV, you see the video as a small rectangle only with a huge black border?

[Ijven 4]

@Luke Thanks! I'll look to upscale the files through software and save the files on a higher resolution that way.

@softworkz No, the scaling of the video format on the 4K TV is alright, its just that the resolution stays the same aka 1 pixel in HD will simply translate in 4same pixels in 4K. there is no enhancing going on which just makes the resulting image, let us say "not so good" or "not as good as it can be". Whereas there is upscaling that creates "in-between pixels" thus effectively transcoding 1080p to 2160p  (In my case 480p to 1080p) making the image "more pleasing to look at" AKA. upscaling not scaling 

Thanks for the quick responses!

Edited August 26, 2022 by Ijven
spelling mistake

[softworkz 5066]

8 hours ago, Ijven said:

@Luke Thanks! I'll look to upscale the files through software and save the files on a higher resolution that way.

@softworkz No, the scaling of the video format on the 4K TV is alright, its just that the resolution stays the same aka 1 pixel in HD will simply translate in 4same pixels in 4K. there is no enhancing going on which just makes the resulting image, let us say "not so good" or "not as good as it can be". Whereas there is upscaling that creates "in-between pixels" thus effectively transcoding 1080p to 2160p  (In my case 480p to 1080p) making the image "more pleasing to look at" AKA. upscaling not scaling 

Thanks for the quick responses!

There is no such thing as "upscaling vs. scaling". There are different scaling algorithms of different quality, though, like bicubic, bilinear, nearest neighbor, etc.

I don't think that a 4k TV comes without the ability to do high-quality scaling, so when the scaled image quality is not as good as expected, this is an issue that needs to be investigated in the context of the client application.

Not all videos are FHD exactly, many are not even 16:9. What would you expect Emby server to do then? Create a 4k video with black bars at top/bottom or at the sides? So no, scaling up at the side of Emby server does not make the slightest sense.
Please report this issue in the client app forum for the LG TV app. 

[Ijven 4]

@softworkz Apologies if I misused some terms. I was indeed looking for different algorithms as in scale with nearest-neighbor scaling vs for instance 2×SaI scaling (for what I ignorently called upscaling as english is not my mother language) or any other filter for that matter. 

Thanks for putting me in my place though. 

Even so, Luke's answer satisfied my needs as I asked if it was configurable, which it is not. 

Thanks in any case

[softworkz 5066]

Nevermind. I'm just trying to maintain a certain level of clarity regarding terms we're talking about as those conversations are read by many others as well.

I didn't want to just push your case away. Proper (=high quality) scaling is bread-and-butter business for a TV, even more for a 4k TV. 
As such I'm pretty serious in suggesting to raise this as an issue for the LG client app. I think there should be a way to achieve a better scaling quality, even though I'm not familiar with the app in detail.

[hapylestat 10]

On 8/26/2022 at 7:22 PM, softworkz said:

There is no such thing as "upscaling vs. scaling". There are different scaling algorithms of different quality, though, like bicubic, bilinear, nearest neighbor, etc.

I don't think that a 4k TV comes without the ability to do high-quality scaling, so when the scaled image quality is not as good as expected, this is an issue that needs to be investigated in the context of the client application.

Not all videos are FHD exactly, many are not even 16:9. What would you expect Emby server to do then? Create a 4k video with black bars at top/bottom or at the sides? So no, scaling up at the side of Emby server does not make the slightest sense.
Please report this issue in the client app forum for the LG TV app. 

what was meant, I guess, is that if you have SD kind of source, image quality would be improved with additional functionality of scaling. It is not about deinterlacing, but an AI network like Let's Enchance or waifu2x processing. The problem, this is impossible to do on client hardware, except, like on nvidia shield - they are specializing in this. But still, it is too much for real-time conversion as well - as Emby could only DOWNSCALE using ffmpeg and client software able only to stretch  the video to fill the screen area.

 

So the best course of the action - is to actually re-encode video using Neural Networks and proper software and store the result in the Emby library. 

[softworkz 5066]

1 hour ago, hapylestat said:

what was meant, I guess, is that if you have SD kind of source, image quality would be improved with additional functionality of scaling. It is not about deinterlacing, but an AI network like Let's Enchance or waifu2x processing. 

Strictly speaking, this is not upscaling, even though the output is larger than the input.  

1 hour ago, hapylestat said:

The problem, this is impossible to do on client hardware, except, like on nvidia shield - they are specializing in this.

Most TVs have pretty good scaling algorithms, though, which are equal to the upscaling that Emby could do (if it would).

1 hour ago, hapylestat said:

as Emby could only DOWNSCALE using ffmpeg 

Emby downscales but it doesn't upscale for the reasons explained above.

1 hour ago, hapylestat said:

and client software able only to stretch  the video to fill the screen area.

which is called scaling.

[hapylestat 10]

Quote

Strictly speaking, this is not upscaling, even though the output is larger than the input. https://twemoji.maxcdn.com/2/72x72/1f609.png 

it is. It's called Image quality enhancer, or A.I. upscale.  While bicubic and another ways of interpolation are good, but AI is a next level on top of  them, which basically adding understanding of objects in the video - which making upscaling even better (kinda like DLSS).

 

So it is upscaling, which could make jump from 720p to 1080p with quality near the native 1080p for example. But still, it is not the task for Emby