Forced film option in DVD2AVI never worked for me!

[vince]

Hi, I have riped about 20 NTSC progressive films. The forced film option in DVD2AVI has never worked for me. The audio files are always several seconds longer than the videos and I got the sync problem for all the films. I have to uncheck the forced film option and do the inverse telecine in Tmpgenc. It worked most of the time. Just want to know if anybody used forced film option without sync problem. How do you do it?

[adam]

forced film should not cause sync problems. Are you remembering to encode with the 3:2 pulldown enabled?

Also don't forget to make sure that your film can even use forced film. Preview it and let it get past the opening credits. If it says %95 film or higher and stays there then forced film will work. For anything else you will get serious interlacing artifacts and probably desync.

I use forced film for just about every dvd I rip and I have never had any problems.

[bertmartin]

Vince: I used forced film on Planet of Apes and it didn't work for me. I also used inverse telecine in TMPGEnc and likewise it didn't work. I used 16:9 with forced film (didn't work). The picture would move forward very fast for a fraction of a second and audio sync would be lost. Then later it would catch up. I encoded with just defaults (no inverse) and it was acceptable. I didn't preview or do the 3:2 pulldown, however. I would like to see a good discussion on this since I didn't quite understand what I was doing anyway. For example why preview?
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[adam]

bertmartin: For most dvds the film is stored in its original 23.976fps format and uses flags to telecine the video as it plays. Forced film in dvd2avi basically extracts the film as it is, in its original format. Not all dvds are stored like this however and if this is the case forced film will not work. You must preview the video and look at its properties,
% film, in order to determine whether or not your film is eligble for forced film.

In regards to your experiences with forced film, you cannot use forced film and not use the 3:2 pulldown. Force film retains the original 23.976fps which you will later encode in. The 3:2 pulldown is a flag which tells the dvd player to do an auto telecine to 29.97fps, which is required for ntsc playback. Some dvd players will automatically autotelecine the video anyway, in which case the 3:2 pulldown isnt necessary but in my experience most dvd players require this flag. Without it the picture will jump around and lose sync like you experienced. If you are making a vcd then 23.976 is a supported framerate and you only need encode it in this manner to make use of it. If you are making a SVCD then you MUST use the 3:2 pulldown feature either in TMPGenc or run your video through pulldown.exe if you encode in another encoder.

Just in case you didnt already know, forced film allows you to encode in 23.976fps and have it played back at 29.97fps, thus decreasing your total number of frames by %20. This means that either your quality will be increased by %20 or your filesize will be decreased by %20 yet still have equal quality. The benefit you get from using ntscfilm (23.976fps) depends on the mode you encode in, 1-pass vbr, 2-pass vbr, or cbr.

I cannot stress enough the SEARCH function on this forum. This topic has been thouroughly discussed dozens of times already.

[vince]

Hi, all the films I ripped are 98% or 99% film, progressive and I did use 23.976fps and 3:2 pulldown when play back, I used inverse telecine filter, so the setting should be correct. When I use forced film in DVD2AVI and encode in Tmpgenc, the audio lags video more when the time goes. I check the lengths of video and audio, the video always has the same length as the original film, but the audio is always several seconds longer than the film. If I don't use forced film, both video and audio will be longer than the film and they are in sync. Just want to know, when you use forced film, do you get longer audio than the original film? If your video has the same length as the film, how can you get them in sync? Thanks,

[sommersby]

WOW, you are doing something majorly wrong and I don't think the problem is forced film in dvd2avi, I have done over 300 dvd rips using forced film option on every one, even the few that flashed between progressive and interlaced on preview, every rip has come out great! Are you selecting the forced film template in tmpgenc, the only other thing I do is select either 4:3 or 16:9. I have always used the guide at dvdripguides.com and have never found anything better or worth changing to.

[sommersby]

since your audio is going farther out of sync as the film progresses that tells me you are selecting the ntsc vcd template and not the ntsc film template, also in settings select the A field first when doing forced film encoding, all should work fine.

[sommersby]

also DO NOT USE inverse telecine filtering when encoding using the film template, just follow the guide at dvdripguides.com and you will be very happy with the results.

[adam]

vince if you used force film and the inverse telecine filter in TMPGenc then that is your problem. You should only use the inverse telecine filter if force film is not an option in dvd2avi (not %95 or higher film.)

As far as your audio sync problem, this may just be due the limitations of TMPGenc. As far as I can tell it does not add proper SVCD scan offsets during encoding. Remultiplexing may fix this but your best bet would be to use bbmpeg for multiplexing. It is the only svcd compliant multiplexor I have every found. When I use TMPGenc to multiplex my svcds always go progressively out of sync both on my pc and on my dvd player. Bbmpeg multiplexed svcds play in sync not only on my pc but in every dvd player I have ever tried.

[vince]

The audio of the .wav file created from DVD2AVI is longer than the original film, it should have nothing to do with the templet used in Tmpgenc. When I opene the audio filter in Tmpgenc, and slide the slider all the way to the right, I have a time for audio. If I open the source range and slide the slider all the way to the right, I have a time for the video and it is shorter than the audio. I followed all the steps in DVD2AVI. I didn't downsample from 48KHz to 44.1KHz in DVD2AVI, could that be the problem?

[vince]

I didn't use forced film when I use inverse telecine. The result was good for most of the films except they are several seconds longer which is not noticeable anyway. I am just frustrated that the forced film is not working for me. Thanks,

[adam]

I don't think TMPGenc tracks the audio and video times the same. There is always a descrepancy between the audio and video, just ignore it.

"I didn't downsample from 48KHz to 44.1KHz in DVD2AVI, could that be the problem?"

It depends. Please be a little more specific with your info, you can see that me and sommersby have already been confused once because of misleading wording. Are you not using dvd2avi to convert from 48 to 44.1 or are you not converting to 44.1 at all? The standard requires 44.1 audio so if your using 48kHZ then that could cause any number of problems on your standalone dvd player.

If you want to fix your problem eliminate all variables that contribute to non-compliance first. So make sure you downsample to 44100 kHz and make sure you use a compliant multiplexor like bbmpeg. I still think your problem lies in the fact that TMPGenc does not add SVCD scan offsets.

[sommersby]

No, do not downsize from 48 to 44 in dvd2avi, if you just follow the guide at dvdripguides.com you will have no problems, trust me!

[vince]

I followed the guide step by step. I didn't downsample in DVD2AVI and used standard ntsc film templet in Tmpgenc except changed the bitrates. If I use forced film in DVD2AVI, the video will be the same length as the film and audio is several seconds longer, I have sync problem. If I disable forced film and use inverse telecine in Tmpgenc, both video and audio are longer than the film and no sync problem. Just want to know when you guys use forced film, do you have the same length on video and audio or different length but still no sync problem? Thanks,

[bertmartin]

somersby: I used the dvdripping guides but still had a problem with Planet of Apes. Used DVD2AVI w FF and TMPGEnc 2.52 with NTSCFilm, 16:9 aspect ratio, no 3:2 pulldown, high quality. I was doing a VCD so there was no mention of the 3:2 pulldown option since its for SVCD as adam points out. Wonder if I should try the 3:2 pulldown anyway? I have an Apex 660.

adam: Yes I did a search but a lot of the old threads are not accessible for whatever reason. Also this is the best thread so far on Forced Film due to your superior knowledge and pedantic style. Very comprehensive. Great!!

Thanks :P

[sommersby]

vince:
If you change the bitrates you are no longer following the guide and are no longer creating a vcd, if you want an svcd then follow the guide pertaining to svcd or xvcd.

bertmartin:
if doing a vcd then do not use 3:2 pulldown, if doing an svcd then follow the guide for doing that. if you are capturing at 480x480 then you need to use 3:2 puldown, on a rip I don't belive you ever use the 3:2 pulldown, not sure as I always use dvd2svcd on the rare ocations I make an svcd. But it wouldn't make sense to use it as it is used to bring the square capture of 480x480 down to tv ratio.

[adam]

Sommersby the 3:2 pulldown really has nothing to do with resolution or aspect ratio. As I stated before it is a flag which tells the dvd player to do a real time telecine of 23.976fps encoded film into 29.97fps which the ntsc standard requires. The vcd standard supports 23.976fps so all vcd compatible dvd players are supposed to automatically telecine 23.976fps vcds. The 3:2 pulldown option for vcds simply is not an option. The standard doesnt support it so I doubt you would be able to get any program to add it to an mpeg1 stream. It's really simple, if you are encoding in mpeg2 at a framerate of 23.976fps then you should always use the 3:2 Pulldown option. This is the only time that this option needs to be used.

bertman, I apologize I didn't realize limitations had been put on the search function. Is POTA the only rip that you used force film on experienced loss of sync? As I stated all vcd compatible dvd players are supposed to auto telecine 23.976fps vcds. The problem is that not all dvd players do such a great job of it and often the result is sync problems.

vince, I feel like I am repeating myself here. If frameserving through dvd2avi it is very common to have your audio time listed as different than your video time. This should have no effect on sync. I do not know why your svcds sync when you IVTC and not when you use force film but isnt that a mute point if your using a non-compliant multiplexor to begin with? The vast majority of hardware and software dvd players use the SVCD scan offsets to maintain sync during svcd playback and as far as I can tell TMPGenc does not add these, at least without remultiplexing. Please just TRY to use bbmpeg as I can guarantee that it will add the proper SVCD scan offsets. You can find bbmpeg in the tools section and there are guides on how to use it in the svcd conversion guides.

[vince]

Thanks Adam for your excellent explaination. I am using bbmpg to re-multiplex files to fix the sync problem when played back on my DVD player. I didn't know it could fix the sync problem when I played back on my computer. I will give it a try.

[sommersby]

Thanks adam, like I said I have been doing vcd's for over two years but very few svcd's. And then I only use dvd2svcd as it has always worked great for me and am happy with the results.

[enkidu101]

I haven't seen this posted anywhere, but I just wanted to let people know that I have audio symch problems when using ForceFilm in newer versions of DVD2AVI. If I use the original 1.76 version, I never have audio sync problems.

If you have sync problems, try a different version of DVD2AVI... this is wat helped me.