What framerate should I choose when transcoding?

[Kelesis]

I know this question is more about video editing than about Recode, but since it's directly related to Recode's transcoding process, this forum seems appropriate for this question.

Most source video files I have are either 29.97fps (NTSC DVD) or 23.976fps (BD), and I usually end up either upscaling or downscalding them (respectively).

So my question is - what framerate should I choose, for the best viewing experience?

I suppose the obvious answer would be "the higher - the better", but I'm guessing there's more to it than that.
While choosing between 25fps (PAL) and 29.97fps (NTSC) has to do with the type of target TV (which is pretty irrelevant, nowadays, as far as can tell), I can't help but wondering why would professional editors choose a framerate of 23.976fps for HD movies and TV shows? Why not 30, 50, or even 60?

Wouldn't it make sense that the framerate should get higher as new TVs and monitors support those higher framerates? Why go back from either 29.97 or 25 to 23.976? Could someone please enlighten a painfully ignorant soul? :P

Thanks. :)

K.

This post has been edited by Kelesis: May 7 2012, 03:11 PM

[wither]

This should explain everything- http://en.wikipedia.org/wiki/Frame_rate

[Mister_M]

In addition to wither's wikipedia-link, that explains this topic very well, I want to give a few infos regarding the encoding/transcoding of videos/movies.

It still does matter, if the TV is PAL or NTSC. PAL TVs have a Hertz value with a multiple of 25 fps (50 Hz, 100 Hz, 200 Hz, 400 Hz and so on). NTSC TVs use a Hertz value with a multiple of 29.97 (30) fps (60 Hz, 120 Hz, 240 Hz, 480 Hz and so on). That has an effect on media files when playing them back.

Movies and TV shows sometimes use the standardized progressive frame rate of 23.976 fps (NTSC) or 24 fps (PAL). Those frame rates are the standard for blurays. Here you won't really see a difference, when converting.

But I'll give you the same statement like in your upscaling thread: WHY do you want to change the original? The change of frame rates will lead to glitches in most cases, especially when the video will be converted from NTSC-like frame rates to PAL-like frame rates. The only possibility to avoid this, is to use a multiple of the original frame rate.

Every TV nowadays has a more or less good interpolation unit. There's really no need to set other frame rates than the original. It will lead to more pictures per second, which will again result in larger file sizes.

[Kelesis]

This should explain everything- http://en.wikipedia.org/wiki/Frame_rate

Kk, thanks, I'm going to read through this page when I get home, so I can free the time to actually wrap my head around it better and understand that stuff. :)

But I'll give you the same statement like in your upscaling thread: WHY do you want to change the original? The change of frame rates will lead to glitches in most cases, especially when the video will be converted from NTSC-like frame rates to PAL-like frame rates. The only possibility to avoid this, is to use a multiple of the original frame rate.

Every TV nowadays has a more or less good interpolation unit. There's really no need to set other frame rates than the original. It will lead to more pictures per second, which will again result in larger file sizes.

So in other words, are you telling me that the framerate is insignificant, because my TV is going to be able to handle whatever framerate the original video comes with anyway?

Practically, I can relate to the "Leave it alone, you'd only make things worse!" attitude, but I guess I'm too curious for my own good. LOL. I guess I should make the effort to do some extensive reading, starting with that Wikipedia page.

This post has been edited by Kelesis: May 7 2012, 06:23 PM

[Mister_M]

So in other words, are you telling me that the framerate is insignificant, because my TV is going to be able to handle whatever framerate the original video comes with anyway?

I didn't say the frame rate is insignificant... Au contraire, mon ami, you should read my post more carefully! ;)

Practically, I can relate to the "Leave it alone, you'd only make things worse!" attitude, but I guess I'm too curious for my own good. LOL. I guess I should make the effort to do some extensive reading, starting with that Wikipedia page.

I didn't generalize, that converting the frame rate will make things worse. You can do that, if you want. I adviced you to use a multiple of the original frame rate, when you really want to convert it. But be aware, that Recode has a max. value of 30 fps, at least when using the H.264 profiles.

[Kelesis]

I didn't say the frame rate is insignificant... Au contraire, mon ami, you should read my post more carefully! ;)


I didn't generalize, that converting the frame rate will make things worse. You can do that, if you want. I adviced you to use a multiple of the original frame rate, when you really want to convert it. But be aware, that Recode has a max. value of 30 fps, at least when using the H.264 profiles.

Kk, I suppose I need to learn more about this subject before I can wrap my head around those issues.

Thanks for your detailed explanations, I appreciate it. :)

Thanks,

K.