Why do we have to convert 25 fps to 23.97 fps ?

[Snowcrash]

Yep I agree with that. Unfortunetaly there is not a lot of animes with an original rate at 25 fps.

And even if an animated movie was created in Europe, for example Les triplettes de Belleville or Persépolis, I suppose the animators do their work at 24 fps ?
And they convert it at 25 fps ?

If resume for converting :
- in NTSC countries (with japanese or american anime) :24fps --> -0.1% --> 23.97 fps --> 29.97 fps (telecine) so the converting operation is not too difficult.
- in PAL countries (with japanese or american anime) : 24 fps --> -0.1% --> 23.97 fps --> 29.97 fps (telecine) --> 25 fps so the converting operation is quiet messy
- in PAL countries (with european anime) : 24 fps --> 25 fps so conversion is just restore24 ?

Do I am right ? I suppose there are other cases but those are the main ones, aren't they ?

[Mister Hatt]

If your source is PAL, you need a new source. Your definitions are also a bit wrong. NTSC can be done several ways but it is at 23.976~ to start with, it is not slowed down from 24. PAL countries either process in some way to get from 23.976~ to 25 OR they decimate it down from 29.970 OR it is blended into a 25fps mess with one of several algorithms.

Restore24 does NOT do what you think it does. It is for attempting to reconstruct blend-converted data back to NTSC and then IVTC to 23.976.

[Snowcrash]

NTSC can be done several ways but it is at 23.976~ to start with, it is not slowed down from 24.

I disagree with that : a film is shot at 24 fps not at 23.976 fps. Same for animation, an animator can't create 23.97 image >.>
You can read this page if you want to check : http://www.paradiso-design.net/videosta ... l#transfer

PAL countries either process in some way to get from 23.976~ to 25

PAL countries don't start at 23.976 fps but 24 fps : they sped up the film at 25 fps to get the PAL standard. Of course if they get a NTSC video, it's a complete mess to do the transfer.

And a nice and very complicated figure to explain that :p

Spoiler :

[Mister Hatt]

That is so fucking kawaii you have no idea. Unfortunately, I work in film production and I can assure you that 24fps is not the capture rate in most studios. I also work in importing overseas films and converting them to PAL (in fact it's my specialty) and you're wrong about that one as well. We speed up to 24fps from 23.976 and then apply a soft pulldown or a blend matrix to it. There are ways of getting NTSC->PAL without ruining it TOO badly, so I wouldn't call it a mess, but it is still far from ideal. Just because some junky website says it's done one way doesn't make it true. I'm speaking from industry experience here.

[post-it]

why not just convert it to 120 fps and then divide it as needed ....

[mirkosp]

why not just convert it to 120 fps and then divide it as needed ....

Doesn't really change anything. When you convert to 120 you're just duplicating frames, and then you'd drop them again to go to the actually desired framerate... so the result is the same.

[post-it]

.. then ... ? .. is there a place, somewhere in the video-stream, that has the frame-rate "written in it" ??

{ What I mean is; something "somewhere" should have the frame rate "used" and "converted-to" ... ? }
it would be rather silly "not" to have the play-back information available within it because SOMETHING has
to let the TV Signal know "when" to "switch fields" and "when its progressive" ... right?

[Mister Hatt]

The 120fps hack is a dirty method of making pseudo-VFR in AVI containers. It is NEVER a good idea and serves only to make your encoding process take longer while using more ram and bitrate than necessary. You've been told like a hundred times by now post-it, stop giving people bad advice.

[post-it]

The 120fps hack is a dirty method of making pseudo-VFR in AVI containers. It is NEVER a good idea and serves only to make your encoding process take longer while using more ram and bitrate than necessary. You've been told like a hundred times by now post-it, stop giving people bad advice.

I'm not giving advice, I'm asking questions: unlike you, I'm not GOD!

I've seen people converting files to 120 fps and wondered "why" but I never got an answer!
( this caused many people many problems during Romeo X Juliet; we set up IRC's for Corrections and
were swamped with know-it-all's like you! {{ check it out, it is recorded on the orgs listings! }})

At more than 10 times I've asked, "where are the stream markers located for Frame Rate" and recieved no answers!

I've asked many times on many different occasions, "how to do things" and the first thing I usually get is your fat-lip.

This board was put together for people to ask questions and find answers: No GODs Allowed! ( except Zero )

..

btw .. any of those three questions listed can be answered at any time Mister Hatt! Put-up -or- Shut-up!

[mirkosp]

The real problem is that your wording makes people think you're trying to give suggestions instead of asking questions, post-it.
Anyway, if you want to know where the framerate info is stored, well, I assume that varies depending on the container and the codec, so there is no generic answer, but I wouldn't be able to tell where exactly that's stored for a certain format, it's not something I know nor I've ever searched for, since things like medianfo and avinaptic can already tell me the framerate of a given source, if I need to check it... but well, I guess if you feel like it, you might be able to find something by poking around in the file in a HEX editor.