Thank you so much for all the replies! I appreciate your taking the time to post them. They are potentially very useful, although they also do raise new questions for me. I will post the most pressing ones below.
It depends on the footage you process, but most films are produced in 24p (23.976fps progressive).
Later DVDs are often recorded in 24p, but early DVDs may be telecine and recorded in 30i (29.97fps interlaced).
For DVDs recorded in 30i, Inverse Telecine(30i → 24p) is required.
How would I know if the particular footage needs Inverse Telecine (IVTC) or not?
However, the current TVAI does not have an Inverse Telecine function.
Interestingly, among the films I have upscaled so far (always using the Proteus model), there have been some cases where the source video (a specific example: a 1948 film ripped from a 720x480 DVD) was 29.97fps (at least judging by what VLC is showing me when I play the file; MediaInfo is not showing any fps information at all in this case) and after processing with Proteus, the resulting video is 23.976fps. Would that be because IVTC happened somehow? I was actually quite amazed to see that change (which did not effect the length of the film). Or is it that the VLC information regarding the source file may be incorrect? Could it be the case of a “later DVD recorded in 24p”?
have you tried the simpler option of Deinterlacing and upscaling using Dione: DV (or TV) in one shot as a single step?
Yes, this is pretty much option 2 I mentioned in my message: " 2. Deinterlace, upscale and convert pixels to square ones using Dione" - all in one single step. The results seem good to me. The resulting video is 59.940 fps.
Taking this into account (the seemingly good result), and contrasting it with this statement:
For DVDs recorded in 30i, Inverse Telecine(30i → 24p) is required.
would that imply my footage did not really need IVTC? If so, this brings me back to the question of how would I know, before processing, that the footage needs IVTC or not.
A further question: if I end up with a 59.940 fps video (movie) after the processing, is there anything wrong with it? I mean, would it have been better to have converted the footage to 24fps before upscaling (to also end up with a 24 fps processed video)? From what I’ve read on the web, people would say there is no ideal frames per second rate, it all depends on what I need, and they would say 24fps gives a “movie” feel to the video, while doubling the fps when deinterlacing (to 59.940 fps in case of a 29.97 fps source video) is highly recommended and ensures smoother motion. The Dione model does exactly that (doubles the fps when deinterlacing), so if the resulting video looks good, am I done or should I worry it’s not 24 fps?
And the last question for now: regarding the first method I mentioned - deinterlace the 720x480 video (ripped from a DVD) and convert it to square pixels using Dione (without upscaling), then, as a separate process, upscale it to FullHD using Proteus - is there any reason why this would be not recommendable? (like that for example it’s not advisable to process the same video twice using different models or something - I’m asking because I don’t know if there may be any such rules).
Thank you in advance for any replies
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