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Info: Gigapixel AI vs infognition Super Resolution / What to use to upscale SD to HD or 4K — Page 2

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phoenixobia said:

As for IVTC, I haven’t tried Avisynth yet but I’ve read about it and would try it. I am aware of the change of pattern that can happen but I think that could be the case with any algorithm. As you mentioned, doing those by hand to produce progressive results is the best way to have perfect results but I don’t see how it can be fast. Shouldn’t that take forever? Please elaborate on that.

The speed of a hand-made IVTC in avisynth (using SelectEvery) is lightning fast. But I think you meant to produce the script. The script that handles the different patterns by hand can in most cases (>99%) be made in about 15-30 minutes. There are only three patterns in 99,5% of all cases, the only exceptions of this I had with Japanese NTSC-sources so far, they sometimes have a different way of pulldown, but also not often.
So, you just have to specify those three patterns, handle them with variables, and put all together with Trim’s.
A question of how exact you want to have your result. In a professional setting, where you have to do IVTC for series with >100 parts, you sure wouldn’t do this by hand, but if you do something with love - as everybody here does, I think - and willing to spend some time more to achieve the very best result, it’s no question, is it?
I can only encourage you and everyone to try avisynth. It’s the most flexible thing to handle video out there, and you have FULL control of what’s happening.

Second, I’m not sure I understand the part you talk about telecining while scanning.
If the original footage has been 24fps film/animation and telecined (3:2 pulldown) to 29.97fps which is the case with Laserdiscs, IVTC is the process to get rid of those added frames and turn it to 23.976fps. The results should have no jagged edges or as you say staircase-artefacts and no half resolution. My IVTC video has no rough edges if that’s what you mean, so please explain this.

This ugly pulldown-thing that you have with NTSC (I am lucky to live in PAL region) is produced in different ways. Sometimes while scanning as one process (older sources), or later. But this is not the point of what I meant.
The point is compressing while interlaced. Maybe this Laserdisc-source comes from an older scan. At a very early “stage” it has been copied to a - let’s say - DigiBeta-cassette that then was archived. DigiBeta-format is quite good, but compressed, not much, but lossyly compressed. If the source copied to a DigiBeta is progressive, you won’t notice the compression with your eyes, no chance. But a pulldowned source is combed… The most ugly thing with pulldown is, that in almost any case you do not simply add frames by doubling every fourth, no - it’s fields that are added - as you know of course - that results in combing. Lossy compressions - reagrdless of how good they are - do harm in these cases. Let me specify:

film --> scanned with pulldown (telecined) --> stored really uncompressed or losslessly compressed --> IVTCed
would give you 100% progressive frames back, that’s right.

film --> scanned with pulldown --> maybe once stored uncompresed --> copied to and archived as DigiBeta --> even copied to another medium via SDI or similar interfaces --> IVTCed
will result in small jagged edges (thanks for the term), that increase with sharpening, even with AI. There is no lossy compression algorithm that does not produce ANY edges when handling combed material. You won’t notice it in most cases, but you will see it, if you sharpen, and that’s what is done here.
The later the Pulldown happens, the higher are chances to get more or less artefactless original progressive frames back.

Below are the images. It’s best to download and see at 100% but you can still see the difference here.

These look damned good! One could critisize many things, but to my feeling they really look good. I only doubt that this couldn’t have been achieved also with more conventional things than AI - and I doubt that GP doesn’t take advantage of these. 😉

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FrankB said:

The speed of a hand-made IVTC in avisynth (using SelectEvery) is lightning fast. But I …

Interesting. Makes sense. I just don’t know scripting and how to learn to do it. But I know it’s great.

This ugly pulldown-thing that you have with NTSC (I am lucky to live in PAL region) is produced in different ways…

PAL Has 2 really good benefits, 1 as you mentioned not having this ridiculous interlacing issue with film, 2 it has more horizontal lines of information for the picture. But the big downside is the frame rate when it comes to 24fps film, that shift of speed and change of pitch in the audio after conversion to 25fps is so noticeable and annoying to me. I know how to convert a PAL source back to progressive 23.976fps and change the audio speed to match the new framerate to reverse this effect but when audio speed becomes slower, audio quality decreases to some extent because it goes from high pitch to low pitch.

it’s fields that are added - as you know of course

Yes, I meant fields combed as one frame.

film --> scanned with pulldown (telecined) --> stored really uncompressed or losslessly compressed --> IVTCed
would give you 100% progressive frames back, that’s right.

Yes, Laserdisc is uncompressed because it’s analog, correct?

These look damned good! One could critisize many things, but…

Exactly, It may not be perfect and there are still issues or limitations but what it’s able to achieve is incredible. 😃

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phoenixobia said:
Interesting. Makes sense. I just don’t know scripting and how to learn to do it. But I know it’s great.

-Install AviSynth (for better compatibility first 32Bits)
-Write a script (you can do it with notepad) containing an Input-Source and a return, f. e.:

v=avisource(“D:\Videos\1.avi”)
return v

Save it with extension AVS.
Every video app that opens the avi via the installed handler correctly opens this avs now as a video, VirtualDub2 recommended. That’s all. When you write something between the two lines it will become interesting. There are also many more “source”-filters that can open nearly any possible format. I would recommend the package LSMASHsource, that comes with LWLIBAVVIDEOSOURCE. Opening with this can last a while, because it writes an index, but will afterwards be fast. And it handles sources very much correctly without changing anything. There are more, also based on ffmpeg. Between the lines you can do almost everything with the video, more than you ever dreamt about…

But the big downside is the frame rate when it comes to 24fps film, that shift of speed and change of pitch in the audio after conversion to 25fps is so noticeable and annoying to me. I know how to convert a PAL source back to progressive 23.976fps and change the audio speed to match the new framerate to reverse this effect but when audio speed becomes slower, audio quality decreases to some extent because it goes from high pitch to low pitch.

Yes, you are right. Especially a problem when you release something on BluRay with correct 23.976 or 24 fps, but the dubbing had been made for PAL-TV. So you hve to slow sound down in speed. The quarter tone lower in my opinion is not as hearable or annoying as the lower speed. One can correct the pitch, but this does not solve the problem. You can only release the BluRay in 25fps, but this causes other problems and the picture remains too fast…
In spite of these problems I highly prefer PAL, when I look at Pulldown and IVTC issues.

film --> scanned with pulldown (telecined) --> stored really uncompressed or losslessly compressed --> IVTCed
would give you 100% progressive frames back, that’s right.

Yes, Laserdisc is uncompressed because it’s analog, correct?

Yes, but the problem I mentioned was not the Laserdisc or your transfer to harddisk, but the possible steps that happened before to the material from scanning the progressive zelluloid-film until it had been copied to a Laserdisc. But I fear we are somehow off-topic meanwhile…

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Thanks for the tutorial!
Yes, let’s not go off topic from the original post by Avatar_Emil_Borg. Hopefully he’s seen the demonstration images I posted as he was wondering about the Gigapixel app and all.

Thank you for the detailed info.

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phoenixobia said:

Thanks for the tutorial!
Yes, let’s not go off topic from the original post by Avatar_Emil_Borg. Hopefully he’s seen the demonstration images I posted as he was wondering about the Gigapixel app and all.

Thank you for the detailed info.

Yeah, thanks. And yes, I’ve seen those images.

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It looks fine to me, but I’m not sure if I can shell out $300 on something like this.

Ol’ George has the GOUT, I see.

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FrankT said:

It looks fine to me, but I’m not sure if I can shell out $300 on something like this.

Yes, It’s a bit expensive. Would be nice if it was a lifetime license but looks like updates are not included, although you can still use it. Maybe not renew every year, but still.

Or even fund it by multiple people who can share the license but possible that the license only works for one.

It is also likely that other companies like Adobe come up with their solutions, since AI is growing.

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Over on Blutopia, you can now enjoy the first season of Star Trek: Deep Space Nine in 4K with a 1080p release coming in the future. Personally, I’m waiting for the 1080p release as the 4K release apparently has some aspect ratio issues, so if anyone can share their thoughts on this upscale, I’d appreciate it.