Field Order Transition Questions

[robo731]

I'm encoding and deinterlacing some mpeg files which are interlaced predominantly with tff. When I demux them with DGIndex I get the Field order Transition error. I saw this thread here: http://forum.doom9.org/showthread.php?t=134623 but some of it was over my head, I'm somewhat new to encoding. Is there a way to tell when the field order changes or if it's necessary to fix it? And how can I tell when fixing it will cause A/V sync issues?

[Guest]

Can you attach the full D2V file please?

You can use Tools/Parse D2V to see where the transitions are.

[robo731]

Yeah, thanks for responding. Here's the fixed one, the original, and the log. I'll parse it to find where the fields change. Is there a way to convert the picture number into a time code so I can find the spot in the video and see how it encoded? Also, could you please explain to me what rff is, from what I've found it's a repeated frame or field? And lastly, can you break down what the 0, 1, 2, and 3 are?

[robo731]

The video is predominantly tff, but if it switches to bff when there's a field transition, then those parts where it changes will appear choppy. Is there a deinterlaces that can detect field order transitions or read them from the d2v file?

[Guest]

Is there a way to convert the picture number into a time code so I can find the spot in the video and see how it encoded? The easiest thing is to make a script with just mpeg2source() and then open it in VirtualDub. You can navigate by frame number to see what happens at your transition points.

I also recommend doing that with both the original D2V and the fixed D2V. Please report what you get with each.

Also, could you please explain to me what rff is, from what I've found it's a repeated frame or field? And lastly, can you break down what the 0, 1, 2, and 3 are? I'm afraid I don't have time to make a basic tutorial for you. There is ample material on the web that you can find to learn about pulldown. Briefly, the number encodes the TFF and RFF flags. There's a decent guide about that stuff on the forum somewhere.

[robo731]

Ok, I went though the d2v files and I also checked the two separate encodes of each version, but I don't really see any differences between the 2 files. What exactly should I be looking for?

[Guest]

I'm sorry for not having the time to bring you up to speed on telecine, field order, etc. But if you send me a private link to the source file I'll have a look at it and advise you of proper handling.

[robo731]

That's ok, if there's no simple explanation then don't worry about it. I'll look it up myself if it's complicated. Since I don't see any problem with the file that has not been fixed, I'll just use the not fixed versions of these files. I'm using QTGMC and it doesn't say anything about setting field order in the manual. Can it determine the field order from the d2v? That way when it switches it can still deinterlace properly? Or do you know of another deinterlacer that can detect field order transitions and adjust accordingly?