Video Frame Rate Not Same as Original

tjkaz

Using latest official release 8085, and just backed up An American Tail to mkv.remux. Resultant file had frame rate as 23.976, but original was 29.970. I tried to fix the frame rate issue with mkvmerge as I've seen this with Fab a couple times before. However, the audio was so far out of sync it was like I was watching another movie. Attached is a list of the video section of the file from mediainfo.
However, while writing this, I performed a similar backup using VOB passthrough and the backup seems to have worked perfectly! See attached mediainfo listing showing the correct framerate.

Complication

Technically, the framerate of the original video is 23.976 which is for film. To make it DVD compliant, the DVD authoring process adds repeated frame markers (pulldown) to achieve 29.97fps. DVDFab recognizes that the real video is 23.976 which is what it should use when doing a conversion. However, you are correct in that a remux should probably keep the 29.97fps in order to avoid the audio problems.

Sorry I can't help with the problem but hopefully you'll find the information useful none the less.

tjkaz

[QUOTE=Complication;82032]Technically, the framerate of the original video is 23.976 which is for film. To make it DVD compliant, the DVD authoring process adds repeated frame markers (pulldown) to achieve 29.97fps. DVDFab recognizes that the real video is 23.976 which is what it should use when doing a conversion. However, you are correct in that a remux should probably keep the 29.97fps in order to avoid the audio problems.

Sorry I can't help with the problem but hopefully you'll find the information useful none the less.[/QUOTE]

Interesting....but vob passthrough appears to have worked just fine. Seems the issue is with mkv.remux - right?

AGJ

Did you try using 29.970 for the frame rate to see if that gives you audio in sync for the mkv?

tjkaz

[QUOTE=AGJ;82145]Did you try using 29.970 for the frame rate to see if that gives you audio in sync for the mkv?[/QUOTE]

Unless I'm missing something, there's no way to change frame rate (or most anything else for that matter) when using MKV.remux. As such, all the drop boxes in the "edit" menu say "same as source". This is my intent - don't want to change anything.

The vob passthrough option menus behave the same, but for some reason this option gets it right every time with the problem disks - original frame rate and no audio sync issues. I've only experienced this problem with the MKV.remux option with several DVDs.

Until this is fixed, I guess vob passthrough is the best option for me.
FWIW, I haven't seen this issue at all with any of my BD to MKV.remux rips - perfect every time!

Hey Fab Devs - perhaps the issue identiefied above could be the reason for all the other's audio sync problems? The forum is loaded with users complaining about sync issues. Just a thought...

tjkaz

Hello,
I continue to have this issue with more and more DVDs that I'm backing up to my server. MKV.remux works great with BD, but for some reason, does not for many DVDs that I've processed, and gives me the results that I posted in the original post. That is, it ignores the frame rate and writes the file at 23.976 even though the DVD was authored at 29.970. In most cases, I'm able to fix the problem afterwards with mkvmerge.
As I also stated, the vob passthrough option doesn't seem to have this problem at all. I wouldn't mind just using the vob passthrough for my DVDs, but for some reason the movie time doesn't seem to come through correctly and the player displays the incorrect movie length (time) and the FFW, RWND are choppy/inconsistent.
There appears to be an issue with the MKV.remux profile when used to backup DVDs.
It would be nice to know if others have experienced this, and if this is a known issue and is being worked in a subsequent program update.

CBR929

Hi tjkaz

I have just run a test using a 29.970 frame rate video that I have and you are correct, the A/V sync is way off.

Can you use a different profile?

I also ran another test using the generic.mkv.h264.audiocopy and having 23.976 as the frame rate and the A/V sync was dead on perfect.

Maybe the developer will see this and get this fixed.
CBR929

tjkaz

[QUOTE=CBR929;88757]Hi tjkaz

I have just run a test using a 29.970 frame rate video that I have and you are correct, the A/V sync is way off.

Can you use a different profile?

I also ran another test using the generic.mkv.h264.audiocopy and having 23.976 as the frame rate and the A/V sync was dead on perfect.

Maybe the developer will see this and get this fixed.
CBR929[/QUOTE]

Thanks CBR929. The closest thing for me to use would be VOB passthrough. I do not want to decode/encode, compress, etc. I was hoping that this would get fixed in subsequent releases, but for some reason it has not been. I just tried 8.1.0.3 Qt and same result. I've tried ripping to HD first, software only (which shouldn't matter for remux), pathplayer enabled, disabled, only when needed, etc. and nothing seems to make a difference.
I used to be able to fix afterwards with MKVmerge, but for some reason, I'm only able to fix about half of them.

Fentao, Ting, other Devs: is this issue on the "fix-it" list??

Complication

Using VOB passthrough and then MKVmerge is absolutely going to create the audio sync problem on many DVDs. DVDFab does not make changes to the stream during VOB passthrough so the video will be 23.976 plus pulldown to make it 29.97 for the DVD. The problem is that many DVDs use irregular pulldown so either you get video jitter or poor audio sync.

I've tried several things to redo the time codes on VOB content from DVD and nothing works. I just have to leave it in the VOB output.

tjkaz

[QUOTE=Complication;90287]Using VOB passthrough and then MKVmerge is absolutely going to create the audio sync problem on many DVDs. DVDFab does not make changes to the stream during VOB passthrough so the video will be 23.976 plus pulldown to make it 29.97 for the DVD. The problem is that many DVDs use irregular pulldown so either you get video jitter or poor audio sync.

I've tried several things to redo the time codes on VOB content from DVD and nothing works. I just have to leave it in the VOB output.[/QUOTE]

Thanks Complication, but I don't use vob passthrough AND then mkvmerge. Sorry if my post was confusing. What I said/meant was I have been successful sometimes using mkvmerge to FIX DVDFab mkv.remux output (perhaps successful 50% of time). I also said/meant that when I use the vob passthrough (only) option, DVDFab does a perfect job 100% of the time with the output - no sync issues. Therefore, was wondering why it was so hard to just fix the mkv.remux profile since they seem to have gotten it right with vob passthrough. That was the only reason I mentioned vob passthrough.

I (and another user/friend of mine) have this issue with many popular DVDs; Godfather (all), Pearl Harbor (Afleck, et al.), Under a Tuscan Sun, and many others.

Complication

There are other problems with the VOB files such as incorrect time codes and difficulty in FF/RW. I don't use MKV.remux but I would imagine that MKVmerge is having the same issue with it as it does with VOB Passthrough.

Like I said, keeping the original MPEG2 stream from the DVD is problematic at best. If I can't use VOB passthrough then I'll normally convert it to H264 in an MP4 with audiocopy using a fairly high bitrate (~3000). Good luck.

tjkaz

[QUOTE=Complication;90296]There are other problems with the VOB files such as incorrect time codes and difficulty in FF/RW. [/QUOTE]
I agree, that's why I want to use MKV (mkv.remux).

[QUOTE=Complication;90296] I don't use MKV.remux but I would imagine that MKVmerge is having the same issue with it as it does with VOB Passthrough.
[/QUOTE]
I am not using mkvmerge with a file made using VOB passthrough. Not sure where you got that from.

[QUOTE=Complication;90296]
Like I said, keeping the original MPEG2 stream from the DVD is problematic at best. [/QUOTE]
But Fab doesn't seem to have any problems with it for VOB passthrough. VOB and MKV are just containers so why does it work with one and not the other?

[QUOTE=Complication;90296]Good luck.[/QUOTE]
Thank you!

Complication

[QUOTE=tjkaz;90303]I agree, that's why I want to use MKV (mkv.remux).
[/QUOTE]
Without converting the MPEG2 to something else you are not fixing the problem.

[QUOTE=tjkaz;90303]
I am not using mkvmerge with a file made using VOB passthrough. Not sure where you got that from.
[/QUOTE]
I did understand what you were doing.

[QUOTE=tjkaz;90303]
But Fab doesn't seem to have any problems with it for VOB passthrough. VOB and MKV are just containers so why does it work with one and not the other?
[/QUOTE]
With VOB Passthrough, DVDFab can dump the DVD VOBs almost as-is (minus the additional audio and subtitle streams). I don't know enough about MKV but I'm guessing that DVDFab is required to package the streams differently which is causing a problem. My point is that mkvmerge from a VOB passthrough file causes the same issues.

Again, I've not found a program that can keep the original MPEG2 video that has irregular pulldown and fix all the timecode issues (not for a lack of trying). VOB Passthrough plays well enough so that is what I use. Do keep in mind that the DVD authors don't really want you to rip the content from the DVD so they make no attempt to create nice clean streams in the background (just what ever a DVD player will play correctly).

tjkaz

Problem Resolved

FWIW, I was able to make perfect MKV backups of the disks that were giving me problems with Fab, by using another program. And, to my surprise, the program loaded the chapters (from the DVD) in the MKV files as well. Very cool, and Fab only does this for BDs.
So,and as I suspected, the disks I was attempting to backup were not problemmatic at all, but DVDFab has a problem with its MKV.remux profile. I wish this will be fixed some day.
Thanks, and hope this helps others with the same problem.