SVCD Frame Rate?

[Debi]

I've encoded a lot of vcd's with a frame rate of 23.97 fps and it works fine. But when i do the same with svcd it plays fine on my pc but it plays choppy on my dvd player. But if i encode the svcd in in 29.97 fps, it plays back nice and smooth on my dvd player. So can svcd's be encoded at 23.97 fps? Has anyone encoded a svcd at 23.97 fps and have it work fine in their dvd player?

[Trahald]

yeah.. svcds should be 29.97 for ntsc.. most players will either have poor playback on 23.976 content.. if they play it at all

all you have to do is run pulldown.exe and it will set flags in it to appear as 29.97 to the player. (tmpgenc and supposedly cce 2.66 ) have it built in

[RadicalEd]

Quite so. 23.976, although an important framerate, was left out of the SVCD standard. Why was it part of VCD and not part of SVCD? Simple, there would be no way to display a progressive film VCD if 23.976 wasn't a supported framerate and the player didnt auto-telecine on playback. The reason for that is because its VCD, you know, 352x240, aka no fields. Because of the resolution's inherent inability to be interlaced, there is no way telecine could be performed on film material, because telecine is a field based frame rate increasing thingie. Things with a res of 480x480 can be telecined fine because of the support for interlacing and fields, so I spose they figured 29.97 would be fine for the only standard framerate (besides 25 for PAL). The simple solution is to use pulldown.exe or if you're encoding in TMPG use the 3:2 pulldown setting for the encode. That way the player thinks its 29.97 fps and plays it fine.

[Debi]

Thanks for the help guys, but i tried the pulldown.exe and it still didn't work. So i'm just going to stick to encoding svcd's at 29.97 fps.

[gft]

BTW, at least on my dvd player I can play svcds encoded at 23.976 and 352x240 -- with pulldown enabled, of course.

...so 480 vertical resoluation isn't necessary for interlacing during plaback.

-gft

[htc10825]

on all "Mustek"-DVD-Players you kann play the 23.976 SVCDs very well - WITHOUT the pulldown.exe(yes, NO use of it!)

I´ve created many 23.976 fps SVCDs without the use of pulldown.exe.
It plaied on my Mustek DVD-56S and SONY PAL-TV @24 fps, so for long file there is a syncron problem. I have to load the audio to WaveLab to do a small adjest in time base.

[adam]

The 3:2 pulldown does not trick the player into thinking the SVCD is encoded at 29.97fps... it instructs the dvd player to do a real time telecine, just as the RFF/TFF flag does for dvds. There may be the odd dvd player which has some specific bugs but for the most part any SVCD compatible dvd player should be able to properly playback a SVCD at 23.976fps with the 3:2 pulldown.

Some dvd players autotelecine all ntscfilm (23.976fps) material. This is why you can get away with not using the 3:2 pulldown flag in SVCDS, but why would you do that? It only makes the SVCD non-compliant on the majority of dvd players. Its going to be played back at 29.97fps regardless, you might as well make it compliant even if the pulldown flag is redundant on your specific player, it still doesnt hurt anything.

[htc10825]

Hi adam, you are my favourite students!

Of cause I´ve remembered all the "compliant" DVD-Player problems. But of cause I had my reasons, too! The keywords are:
CVD-Subtitle, I-Autor muxing, 1CD-rip, low bitrate, choppy play back.

Let me explain it slowly:
All the svcd I´ve made have subtitles. All the DVD-Player that SVCD-Subs support, can handle the CVD style subs very well. But only a small amout of those can play CVD and SVCD style subs. I´ve never seen a Player that only supports SVCD style subs. Please chick it out at www.vcdhelp.com. Also my Mustek V56S supports only CVD style subs.
Furthermore only the I-Author software bring about reliable resaults for subtitles. WinSunMux not. I usually make 1cd-rip for movies btw. 90-125 min. Thus the average bitrate is very low. After applying 2:3 pulldown the I-Author muxer will give an error massage out while muxing. The resaulted SVCD will not be smoothly played back - choppy. But when I mux the video/audio/sub directly without 2:3 pulldown, there is no problem.

With a average bitrate of 1.6 -1.7 Mb/s threae is no such problem. For smaller bitrate I can use bbMpeg to mux then, the file size is 10MB - 15MB bigger(caused by "SVCD scan head"), but play back is much smoother. The bad new is, no subtitle possible.

[adam]

htc10825: CVD style subs are definitley the more supported of the two formats but there are many dvd players which can only play SVCD style subs and not CVD style subs. Aren't most, if not all, Phillips dvd players like this?

I have had slightly different problems as you but with the same result...

I too have a dvd player which only supports CVD style subs but I have no problem with WinSubMux. Its CVD style subs work fine on my Apex AD600a. Exactly what is it about WinSubMux that isn't working for you?

I also have absolutely no problem using nstc encoded mpeg2 files with the 3:2 pulldown in I-Author's multiplexor, at any bitrate. It works perfectly everytime. I'm not sure what's going wrong on your end.

My problem is that I-Author's multiplexor does not give me acceptable results. I always lose sync past 40mins on my dvd player. But I too cannot use WinSubMux for subtitles because mpgxmps will not accept a subbed mpg and for my purposes I have to use I-Author for authoring and I can see no other way of loading the subbed mpg into I-Author. So my only solution is to span every movie onto 3 cdrs and keep the playtime of each under 40 mins. So needless to say I skip subtitles on most movies except where necessary.

BTW: you don't have to use the SVCD scan offsets in bbmpeg if you don't want to. They're also not required by the SVCD standard.

[htc10825]

Let me explain it:

1. For 1cd-rip of movie with 100-125 min. length the resulted bitrate is VERY low. When you mux them with I-Author it will give you a choppy playback. But with bbMpeg and activated "SVCD scan offsets" you will get a much smoother playback. Of cause you can deactive the "SVCD scan offset" which will save you 10-15MB but it will choppy just like I-Author´s muxer. In WinDVD 3.1 it is very choppy, in standalone better, but still choppy.
Go and encode a movie more than 120 min. on one cd(700MB) and you will see what I mean.

2. The movie "The Accidental Spy" has a length of 106 min. When you excute 2:3 pulldown before muxing(I-Author, 1cd-rip), the result is choppy. When you mux them directly without pulldown, the result is almost perfect in standalone.

3. Due to authoring problem I prefer I-Author to WinSubmix, which some is not so compatible for some players.

4. On my Mustek V56S there is no problem with the 40-Minutes-Subs. The subs after 100 minutes are still sync.

5. If you want to know the settings I used to encode the ultra long movie, let me know. In fact, I´ve posted it twice somewhere in forum.

[adam]

Yes I fully understand your problem and like I said it doesnt happen on my end. Regardless of what bitrate I use I have no problems muxing in I-Author with the 3:2 pulldown. The playback is always smooth regardless.

The SVCD scan offsets only aid in maintaing sync during playback, particularly during seeking. I don't see how this could possibly have any effect on the choppiness of your playback. I think this is due more to the differences in the two multiplexors themselves, though I don't know why the choppiness is less with the scan offsets.

On my end...I'm not talking about the subs going out of sync I talking about my audio sync.