Combining Upper & lower field

JohnDale · Post by **JohnDale** » Wed Oct 15, 2008 9:48 am

Hi
There is only one VOB file on each DVD. Which I renamed to mpeg.

1/The UFF DVD under video type is mpeg 2 video,upper field first.

2/The LFF DVD under video type is mpeg2, nothing else. i.e it doesn't say upper field first or lower field first or frame based only mpeg 2 video.

A bit strange aye.

kfenaughty · Post by **kfenaughty** » Wed Oct 15, 2008 11:48 pm

John,

When I created my DVD featuring a mix of UFF and LFF MPEGs, I ticked "Do not convert compliant MPEGs" as one of the options. I just let the DVD creation module do its own thing. No re-rendering took place.

You mention burning 2 DVDs, once with UFF and once with LFF characteristics, so I am assuming they have been re-rendered. Could you try again with your two clips, setting the option to "not convert" as above?

JohnDale · Post by **JohnDale** » Thu Oct 16, 2008 10:14 am

I first placed the video from the two sources in the timeline and converted these to a single mpeg file UFF and LFF. So I had two files one LFF and one UFF. Then I cleared the timeline and selected share, create DVD, Add video file and set the project settings to match the respective mpeg file and created each DVD one as UFF and the other as LFF respectively. I set the mpeg properties to match each file and "do not convert compliant files" was ticked.

kfenaughty · Post by **kfenaughty** » Thu Oct 16, 2008 6:46 pm

John,

Instead of putting the two sources in the timeline and creating a single MPEG (one LFF and one UFF), can you start with a clear timeline, then create DVD, and just add the two different sources at that stage? That is then a true mix of UFF and LFF on a DVD.

It is not important what the MPEG properties are within the burning module, as long as "do not convert compliant files" is ticked. Hopefully they are compliant MPEGs!

JohnDale · Post by **JohnDale** » Fri Oct 17, 2008 9:23 am

kfenaughty
Clear timeline and create DVD. Add 1 UFF file (mpeg2) and 1 LFF file (DV) Then created the DVD as UFF and the result is a mix of UFF and LFF vob files created. Mpeg2 video was split in 2 and both vob files are UFF the DV video as one vob and is LFF. I also created the DVD as LFF with the same results. So it appears that UFF and LFF video can be combined on one DVD.

JohnDale · Post by **JohnDale** » Fri Oct 17, 2008 9:27 am

PS. forgot to say that both DVD's playback fine i.e with no jerky movements or jagged verticals that I can see.

Post by **Ken Berry** » Fri Oct 17, 2008 9:28 am

Just to clarify one point. If you have ticked 'do not convert', you are not creating a DVD as either UFF or LFF. You are merely getting it to burn already compliant mpeg files to the disc using whatever field order they come with.

But I find the results very interesting and useful. Thank you.

sjj1805 · Post by **sjj1805** » Sat Oct 18, 2008 12:18 am

Thanks for sharing the results of these experiments with us and we now know what happens to mixed field videos. It seems the software is even more intelligent than we had first thought.

Black Lab · Post by **Black Lab** » Sat Oct 18, 2008 1:02 am

I would just like to clarify something. In these examples you are putting just LFF clips in one project and UFF clips in another, then burning these separate projects to disc. I assume it is still advisable not to combine LFF and UFF on the same project, as is how this thread began.

Post by **Ken Berry** » Sat Oct 18, 2008 3:19 am

That's still my working hypothesis as well...

JohnDale · Post by **JohnDale** » Sat Oct 18, 2008 4:03 am

Black Lab
I have actually mixed UFF and LFF clips together in one project and cannot see any negative effects in the final DVD.

sjj1805 · Post by **sjj1805** » Sat Oct 18, 2008 12:24 pm

I have mixed field orders in previous projects Previous post

I thought I was just lucky and never bothered to examine the VOB structure.
This is indeed an excellent discovery.