Video frames stutters

[crazyone]

I don't know if the terms or even the forum is the good one, move me if not. I think it's related more to the encoding of the DVD video... anyway...

My problem is simple, i captured two episodes of a popular TV series here and i want to put them on DVD. The capture is almost flawless (about 0.03% frames dropped on 150 000 frames) and the mpegs are very good quality. I can watch them on my computer in WMP without problem. (I used Nero Vision 4 to make the mpeg capture)

Next i make the DVD with those two videos, process is fairly simple and the computer preview in NeroVision 4 works fine. After the burn, thats where things get complicated.

I tried so far 2 DVD players, different brands and quality both show this problem. When the episode doesn't show much movement, you don't realise the problem but as soon as you start to see some movement its like the frames play a random "i'm the first to go" game, and it looks like there's always a frame that goes then the frame before shows, then the next frame (2 frames away) plays then the frame right before plays, etc. So the video seems to glitch. My GF doesn't see this as a big problem but i tried to watch the video for more than 15 minutes and i had a major headache.

Quick Visual explanation:

Frames : 1, 2, 3, 4, 5, 6, 7, 8
Looks like they are played like this: 1, 3, 2, 5, 4, 7, 6, 8

What does this? How can i correct it, is it Nero Vision or maybe a setting?

[jagabo]

You probably have the wrong field order.

[redwudz]

If the file was OK before running through Nero and OK afterwards, then your media would be the first suspect. Try a different brand. If it's not media, then Nero is the problem. First make sure the MPEG-2 is DVD compliant. If so, try a different authoring program.

Using a computer player like WMP is no indication that the file doesn't have problems. Software players can handle some messed up files that a standalone player would choke on. Try a software player like Power DVD that comes closer to emulating a standalone player before you burn to DVD.

And welcome to our forums.

[crazyone]

I just spoke with a DVD/TV shows expert here at work and it seems that this behavior is due to a misconfiguration. I might have captured my videos in NTSC, but the output was made into PAL. I don't get why NeroVision would do this since he knows my region and has NTSC source files but heh, you never know.

I'll also try using WinDVD Creator to make my DVDs, it seems that its better in his opininon.

BTW... what is the field order? (I don't call that a usefull anwser if you don't explain what it is jagabo)

[jagabo]

https://www.videohelp.com/glossary?F#Field

[crazyone]

Could i have recorded the initial MPEG-2 in the wrong field order but WMP displays the video correctly? I'll try playing the video in WinDVD tonight, i think i'll have my anwser...

[jagabo]

Standard definition NTSC video consists of 60 half pictures (fields) per second. Each of these fields can be from a unique point in time (a live video camera, for instance). You see one field at a time, sequentially.

When a computer captures that video it joins pairs of fields together into frames. If the capture device starts with a top field and then adds the next (bottom) field it is Top Field First. If it starts with a bottom field then adds the next (top) field it is Bottom field first. When your DVD player plays the video back on your TV it needs to know which field (of each frame) to display first.

The result of having the wrong order is exactly what you described, except it happens with fields, not frames:

original order of fields: 1 2 3 4 5 6 7 8
wrong field order: 2 1 4 3 6 5 8 7

This results in a fast jerkiness when there is motion -- 30 jerks per second.

The program you used to make the DVD probably misidentified the field order of the MPEG file you captured. There should be some way you can manually override the field order within the program.

[Nelson37]

Field Order is explained in the FAQ, which you are supposed to read.

[crazyone]

Well i fixed that problem. Nero VIsion has a feature called SmartRecode wich skips the recoding of files it captured ""correctly"" (Yea right). I turned it off, force Progressive transcoding and now the video seems fine.

My only problem now seems to be that some times, my videos arent exactly transcoded properly and the sound skips (grrr). I'm quite tired of all this so i think i'll just give it a rest for a few days, i've been trying to put those 2 episodes on DVD for 4 days now, done 8 captures (7 times of episode 2)...

I'll read a complete manual step by step tutorial and stop using nero vision since i think that is my problem.

Thanks all, have a good day

[jagabo]

Well i fixed that problem. Nero VIsion has a feature called SmartRecode wich skips the recoding of files it captured ""correctly"" (Yea right). I turned it off, force Progressive transcoding and now the video seems fine.

You didn't really fix the problem, you just side stepped it and got lucky. Even with progressively encoded 29.97 fps MPEG files the DVD player has to split each frame into two fields and send them one at a time to the TV. (Remember, SD TV can only display fields.) By telling NVE to encode your video as progressive it has ignored the fact that there is a temporal difference between the two fields. If it encoded without 1:1 pulldown flags (which isn't legal for NTSC DVD) you are relying on whatever the DVD player does when it encounters progressive video -- it just happens that your DVD player picked the right field order. If NVE encoded the frames with 1:1 pulldown flags it just happened to get the order right. By encoding interlaced video as progressive you've also cross contaminated the color components of the two fields. This is hard to see unless you know what you're looking for.

The correct solution is to make sure the program gets the field order right when it opens the file. It can then pass this information along to the DVD player. Unfortunately, I don't think NVE lets you override what it thinks about field order.

[crazyone]

Oh i can, when i capture in NVE, i am able to put the mode to progressive, automatic or field order A:B or field order B:A. I always left it on automatic since i didn't knew what it was and still, i know now what it does, but i have no idea how to set it right... I have to capture and test? then recapture if the field order was wrong?

My results were excelent last time, even without tinkering with the field order capture settings, i had 0/80000 frame drop, but for a reason i don't understand, there are capture glitches... might have been the tv terminal that really glitched and sent me these problems, or i should have had dropped frames in NVE to see the problem i have...

(The problems are really like frames were skipped... the sound and video jams for a couple of frames (i'd say around 6 or 7 frames long and they all happen around the same time, the rest of the video is crystal clean...)

[jagabo]

Oh i can, when i capture in NVE, i am able to put the mode to progressive, automatic or field order A:B or field order B:A. I always left it on automatic since i didn't knew what it was and still, i know now what it does, but i have no idea how to set it right... I have to capture and test? then recapture if the field order was wrong?

Yes, but once you have figured out the correct setting you should be able to use that for all future captures.