23.976 fps convert to dvd

[buzzmadman]

could anyone help me ,when i convert an avi to dvd in tmpgenc with 23.976 fps i set the encoder to the same but when i play the converted m2v file it comes up short on time,i tried to change it to ntsc (29.97) and this corrects the film length but playback on the dvd in a dvd players is a bit jumpy is there anyway to convert 23.976 to dvd and have the full film with a smooth appearance??

[adam]

If you convert to 23.976fps in TMPGenc, regardless of whether you are making a DVD or SVCD, you MUST also enable the 3:2 pulldown option. On the video tab, look under "encode mode." Set it to 3:2 pulldown when playback.

The NTSC standard requires 29.97fps playback, if your file is played back at anything else it will be extremely choppy. NOBODY actually encodes at 29.97fps because it is incredibly inefficient. When you encode at 23.976fps, you include the 3:2 pulldown flag, and it instructs the dvd player to do a real time telecine which converts your movie to 29.97fps as it plays. Since you have encoded 20% less frames, and still get the same number of frames during playback, you have freed up much more of your bitrate. The result is that quality is increased by 15-20%.

[Rico49]

If your audio is going to be LPCM audio, then I say encode at 23 fps with a 3:2 pulldown on playback. However, if you're going to use mpeg audio or AC3 audio, then I say forget about 23 fps and encode at a true 25 or 29 fps. 29 fps is considered inefficient if you're planning on using LPCM uncompressed wav audio which makes up 50% or more of final mpeg size. So at 23 fps, you can apply that extra 15-20% savings to your video bitrate. Not worth it tho for a DVD5. If you plan on encoding just one mpeg file per DVD, then a 120 min movie, encoded at an average bitrate of 4700 will yield a dam good quality mpeg file assuming the source is a quality video as well. I only encode at 23 fps if I plan on putting more than one movie per DVD and don't care about chapter/scene selections. I've discovered that several DVD authoring programs have problems working with mpegs encoded at 23 fps particularly with chapter/scene selections.

[Laddydaddy]

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Posted: 2003 Apr 12 20:19

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If you convert to 23.976fps in TMPGenc, regardless of whether you are making a DVD or SVCD, you MUST also enable the 3:2 pulldown option. On the video tab, look under "encode mode." Set it to 3:2 pulldown when playback.

I have made plenty of svcd rips using the svcd film template and never used the 3:2 pulldown. I have never had a problem with choppy films by not using it. Since 23.97fps is a valid frame rate in the NTSC format there is really no reason to use the 3:2 pulldown for an svcd if your original source is 23.97fps.

[adam]

{edit} Just noticed something...Laddydaddy, are you saying that you used the svcd ntscfilm template in TMPGenc? If so then it automatically sets the 3:2 pulldown for you. Just look on the video tab.

Not true at all Laddydaddy, it is the exact opposite.

23.976fps is NOT a valid NTSC framerate. NTSC requires 29.97fps, period. 23.976fps is a supported framerate in VCD only, which means that all vcd compatible dvd players are supposed to automatically telecine ntscfilm VCDs to NTSC as it plays.

For DVDs and SVCDs the only valid ntsc framerate is 29.97fps, and that is why the 3:2 pulldown flag is required. It is true that some dvd players will automatically telecine all ntscfilm footage. So in this case the 3:2 pulldown flag is redundant, but it certainly doesn't hurt anything. It is a simple fact, the majority of dvd players require the 3:2 pulldown flag for mpeg2 video encoded at 23.976fps. Without it you will get very choppy playback.

I'm sorry to say that all of your SVCDs are non-compliant and if you were to try playing them on different dvd players you would surely run into playback problems. You should ALWAYS use the 3:2 pulldown flag when encoding ntscfilm SVCDs or DVDs. It only takes a few secs to do, its not like it takes up any additional space on the disk, and it ensure compatibility.

[Laddydaddy]

Yes I did use the NTSC FILM template in TMPG. I didn't realize that it added the pulldown automatically. Thanks for the advice. One more question. I now use Ulead DVD movie factory v.1.0 to author and burn my DVDs. It will only accept video files encoded at 29.97fps. Do you know if it will accept files made at 23.97fps with a 3:2 pulldown?

[adam]

I don't use that software so I can't speak from experience, but when you include the 3:2 pulldown in your steam, it is essentially handled by all software as 29.97fps material. Every dvd authoring software package I have tried accepts 23.976 with pulldown flag fine. Some report it as 29.97 and some report it as 23.976 though.

[menace]

I tried three movie encoded at 23.976fps with the 3:2 pulldown and NOT ONE of the movies would author with Ulead 1 or 2, dazzle or dvdit. I reencoded all three movies leaving them at 29.97 and they authored just fine. I'm guessing that there is still some hiccups in the authoring programs that do not recognize the 3:2 flags. Mind you I used tmpgenc for the process so other 3:2 pulldown software may give you better results.

Also, if you are concerned with quality, IMHO the difference between the 23.976 and the 29.97 quality wise wasn't that significant.

If you still want to go 23.976fps, spruceup was the only prog that would author properly and its discontinued and has a very simple (err boring) menu system--but it does work. just my $.02

[Laddydaddy]

Adam and Menace, thanks for your input. You've both been a big help.

[adam]

Well I pretty much use CCE exclusively for authoring DVD content, which means I use pulldown.exe to add the 3:2 pulldown flag, and I have yet to run into an authoring software that had problems with my ntscfilm input, so maybe this is a TMPGenc issue. It may be worth leaving the 3:2 pulldown option off in TMPGenc and using pulldown.exe afterwards instead.

As far as quality is concerned, its true that at higher bitrate you aren't going to see the differences between ntscfilm and ntsc as much, but I can still see a clear difference. There are also many other things to take into consideration as well. Few encoders are true field based encoders, which means that they won't analyze each field they will only analyze it by frame. this is not as efficient when encoding interlaced material so the quality can never be as good as with a progressive source. Keeping your movie in ntscfilm has this inherant advantage over NTSC because it is progressive. Also you need to keep in mind future technology. Once you get a progressive tv, you must encode in ntscfilm in order to take advantage of a progressive scan dvd player. Now this is one area where the difference in quality between ntscfilm and NTSC is HUGE.

Also, by keeping your movie progressive you don't have to worry about setting the incorrect field order and you completely eliminate any possibility of introducing interlacing artifacts. Since you have 20% less frames to analyze the encoding time should also be significantly decreased.

[Cornucopia]

@adam:

I know I'm in the minority here, but there are some of us here who do more with encoding and authoring than just Film DVD rips, so the blanket use of a phrase such as

NOBODY actually encodes at 29.97fps because it is incredibly inefficient

is inaccurate at best.
Please could you qualify what you're saying to incoporate something like "Telecined 24fps Film"? Believe it or not, there are Professionally done films that know they are going straight to video-not to movie theatres-and are shot at 30fps and are telecine transferred at 1:1 (or more accurately 30p:60i). Doing a rate change/inverse telecine deinterlace on this type of film would mangle the quality and timing and be LESS efficient than just encoding as 29.97 interlaced. I haven't even mentioned stuff that is totally shot on video.
Sorry to be so nitpicky.

Scott

[txpharoah]

Another person that just doesn't rip DVDs. Wow! They exist!

Yes, I agree. 29.97 is a framerate for captured footage and for straight-to-video releases. Same for home movies. I trie to reduce to 23.976 once, just to try it, and oh boy, talk about yucky quality.

Just had to throw that in.

[adam]

Obviously when I said that, I said it with the assumption that encoding in ntscfilm was even POSSIBLE. When you have the choice, you choose ntscfilm, period. When your source does not originate as film than you are stuck with NTSC. Believe me, I know what its like to be stuck with NTSC because I film alot of DV footage. The limitations of filming in pure NTSC was one of the reasons why I upgraded to a dvd burner because SVCD just wasn't cutting it anymore.

Yes I am only talking about film sources, so shoot me.

If you must know, I mistook the title of the thread for the title of the forum, and thought we were posting in dvd forum.

[menace]

One other issue that you may not be aware of is that when you convert to 23.976 and use the IVTC process--you can either use avisynth, virtualdub or tmpgenc. My experience with virtualdub and tmpgenc is that it guesses the field order wrong occasionally and deletes a progressive frame and leaves an interlaced one--you get a hiccup in your sound and eventually you lose synch. Also, my experiments indicated that tmpgenc did a better job of guessing frames than virtualdub--but it depends on your source i think. If you leave it 29.97 you don't have those problems--a trade off i guess.

[Cornucopia]

adam said:

Yes I am only talking about film sources, so shoot me.

BANG!

That faux pas notwithstanding, I otherwise usually completely agree with you.

Scott