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Post #1325375

Author
FrankB
Parent topic
Info: Gigapixel AI vs infognition Super Resolution / What to use to upscale SD to HD or 4K
Link to post in topic
https://originaltrilogy.com/post/id/1325375/action/topic#1325375
Date created
17-Feb-2020, 7:18 AM

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…