Mixed field order issue

Ercos wrote on 10/3/2007, 4:25 AM
I made a project, using two different cameras: Sony DCR-SR50E (Hard Disk camera) and Sony HVR-V1E (High Definition tape camera).

Problem is that SR50E uses 'Upper field first' field order and V1E uses 'Lower field first'. When I render the project with 'Upper field first', the parts filmed with V1E have flickering movement and when with 'Lower field first', then clips filmed with SR50E have flickering picture. I am rendering video to 'DVD Architect PAL video stream' (MPEG-2). Later I burn it to DVD, using DVD Archidect.

My question is hereby: what do i have to do, to have a finished product without any picture quality issues?

Comments

farss wrote on 10/3/2007, 4:52 AM
Check the media properties of the clips from both cameras, are they correctly flagged as whatever field order they should be?
Vegas should be able to handle having clips of mixed field order order and sort it all out correctly.
For the record the field order you render to should be the correct field order for the output format, that's not the way to correct field order problems, the outcome of doing that can be kind of screwy. By that I mean the output format may flag the field order and the device reading it adjust accordingly...or not.

It sounds to me like one of your sources isn't correctly flagged. The V1E should be UFF in HDV and LFF in DV. That's nothing specific about the V1E, just the standard that the V1 conforms to.

Bob.
DJPadre wrote on 10/3/2007, 5:41 AM
Sadly Bob, Vegas has this issue with interlaced stuff. I been working with intermediate files rendered to huffy YUV interlaced as lower field, however, once processed in VDub, they come out as upper field.
Vegas sees these as upper f, even though the project is lower field, in turn, vegas will try to confirm the field order during playback, which then gives a reversed interlace effect, being that the upper field "drags" along the lower.

To manage this issue, ive reverted back to creating these files using progressive scan. SO i do what i need to do, render my intermediate as progressive, do what i need to do with it in VDub, then reimport that progressive clip into a progressive timeline

In V6, vegas also had this issue when u reversed a clip (right click reverse) by reversing the clip, they fliped the field order which nuked the clip itself.
again teh only way around it was to either render out as progressive tehn reimort THEN reverse, or simply try to run a velocity at -100 and hope you got the trim correct LOL
farss wrote on 10/3/2007, 6:04 AM
Never had any of those dramas and I've been handed some really screwed up stuff from clients.
5 QT clips as .mov files on DVD, 3 LFF and 2 UFF, wasn't too hard to fix once I knew what the problem was.
Somewhere in the dim past I got a finalised project to author to DVD, obviously no one checked the tape too carefully as parts of the tape had the field order the wrong way around. Split the program and corrected the problem all in Vegas.
Reversed field order is pretty easy to pick on a CRT, motion is simply juddery. Maybe the problem you're describing is more complex where the field sequence is messed up, i.e. instead of A,B,A,B it goes B,A,B,A. I recall ages ago someone here having that problem and the only solution was a trip to VDUB to pull some magic that actually swaps the fields.

Bob.
John_Cline wrote on 10/3/2007, 6:19 AM
I, too, have fed some strange stuff into Vegas and it's handled it fine. Also, I've never had Virtual Dub mess with the field order unless I told it specifically to do so. The only way I know of to "accidentally" mess up the field order in Virtual Dub is to crop an uneven number of lines from the top of the frame.

John
Ercos wrote on 10/3/2007, 6:21 AM
Checked the Field tags on clips and they displayed correctly. Finished rendering with 'Field order none (progressive)'. I will let you know it that helped.

Urmas
Ercos wrote on 10/4/2007, 2:09 AM
Ok, only progress was, that now every part of the rendered project has flickering movement. So im out of ideas.

I unterestand that you have fed everything to Vegas, but have you fed it all in the same time. I have rendered also clips made both with V1E and SR50E - they rendered fine. But now I have to mix them together and I only have 3 field order options at rendering: Upper field, lower field and progressive.. We have saying about a crow, stuck in the tar: Beak stuck - tail free, tail stuck - beak free. It feels the same atm. Sad thing is, that I can not re-shoot those scenes also.

Any help will be appreciated!

Urmas
farss wrote on 10/4/2007, 2:31 AM
Some more info would really, really help!
You say clips from the V1E, are they HDV or DV?
HDV is UFF and DV is LFF, which did you shoot?
After you've made the DVD, what are you viewing it on?
SD DVDs are UFF from memory but whatever the standard mpeg-2 DVD templates are in Vegas they work fine.

Bob.
Ercos wrote on 10/4/2007, 4:19 AM
>Some more info would really, really help!
>You say clips from the V1E, are they HDV or DV?
DV

>HDV is UFF and DV is LFF, which did you shoot?
DV

>After you've made the DVD, what are you viewing it on?
Im testing it on TV screen with regular DVD player.

>SD DVDs are UFF from memory but whatever the standard mpeg-2 DVD templates are in Vegas >they work fine.
'DVD Pal' and 'DVD Archidect PAL video stream' templates both have 'Lower field first' by default.

The issue is not about which field order is used by clips. I know that one is using Upper and other Lower. Issue is aboud how to render, so either field orders are converted to one working field order or field order changes in MPEG-2.

Is it even possible to convert to Upper field first to 'Lower field first' and vice versa?
John_Cline wrote on 10/4/2007, 4:24 AM
DVDs can actually be either upper or lower, the encoder sets a flag in the bitstream.

Yes, you can convert between UFF <> LFF. Vegas does this well.

What are you using to view the final DVDs? Which player and what type of video monitor?
Ercos wrote on 10/4/2007, 4:43 AM
I have used Sony Hard Disc / DVD recorder (realy dont remember the model and cannot check atm too) Daewoo standard CRT TV screen. Also i have checked with Samsung DVD player and Sanyo projector. Both options have flickering. On projection screen, the flickering is worse since the screen is bigger :-)

The DVD I am making, needs to play in variety of players.

How does converting frop UFF to LFF work in Vegas? I just choose LFF in rendering options and it converts?

Mabye it helps when I upload some samples online.
John_Cline wrote on 10/4/2007, 5:00 AM
Well, it's good that you've viewed this on a CRT, that's still the best way to spot problems.

We're certain that the DV clips from the Z1 are lower field first. The MPEG clips from the DCR-SR50E are most likely upper field first, although I'm not absolutely certain. Anyway, check the properties of each clip and make sure the DV clips are LFF and the SR50 clips are set to UFF. Since you're in PAL-land, set your project to PAL-DV. Render to MPEG2 using the PAL DVD Architect template.

Of course, I'm not exactly sure what you're seeing when you say the video is "flickering." It would be nice to see some samples.

Another thought... The "E" at the end of the DCR-SR50E model number suggest it's PAL. The Z1 can shoot in both PAL and NTSC. Is there any chance that the Z1 was set to NTSC and you're mixing PAL and NTSC clips?

John
Ercos wrote on 10/4/2007, 5:13 AM
Well they are both PAL, and clips are set correctly also. By flickering I mean that if the object stand still - the picture is fine, but if the object moves - the movement is not smooth but sort of jumpy.

I am also using constant bit rate? Can it be the trouble maker?
John_Cline wrote on 10/4/2007, 5:32 AM
No, constant bitrate is fine, unless it's set too high. What bitrate are you using?

John
farss wrote on 10/4/2007, 5:36 AM
If the object looks fine when it's static but movement appears jerky then yes, you have a field order problem.
Changeing the field order in the rendered output will not fix the problem if one of the clips has the field order the wrong way around, that would reverse the field order of all the clips. So the ones that were correct would now be wrong and vice versa.

What you need to do is go to the Project Media, R-Click the media and under Properties change the media field order.

I suspect it's the media from the HDD recorder that's wrong, try changing that first.

Bob.
John_Cline wrote on 10/4/2007, 6:15 AM
I think Bob (farss) has the most reasonable explanation.
MacVista wrote on 10/4/2007, 7:35 AM
I don't know if this works in Mpg2 but it might be worth trying.

Assuming you are sure that all the field settings are correct, I had this with a recent project rendering to quicktime.

Choosing "best " quality rather than "good" solved it.