DV-AVI Export [fields]

[Ron]

Quick question. When I export to DV-AVI from PE7, what would happen if I selected "No Fields (Progressive Scan)" in the Fields option? Would it degrade the quality at all or, more importantly, what's the difference between BFF and progressive scan?

[Steve Grisetti]

Progressive scan means that the lines of pixels are drawn continuously in one pass -- as opposed to interlaced.

Traditional TV uses Lower Field (or Bottom Field) First interlacing, while DVDs and MPEGs usually use Upper Field First. About the only time you'll see the difference is when you put and Upper Field First video into a project set up to read Lower Field First. The resulting video will often look jumpy when played.

Computer monitors and many newer HDTVs (the one's that have a "p" in their specs, as in "1080p") use progressive scan -- although most usually include software that does a pretty good job of interpreting interlaced video as progressive. (As when you play a DVD on your computer.)

One option that avoids the issue completely is Deinterlacing. What this does is blur the interlaced lines of pixels a bit so that interlacing looks the same as progressive scan. Usually this happens without a noticeable loss in detail.

Long answer, Ron. But did I answer your question at all?

[Bobby]

Bah, humbug. Interlacing should never have been a part of any digital standard. Now we all have to deal with this albatross.

[Steve Grisetti]

You're right, Bobby. And someday soon it will be as distant a memory as the interlaced .gif!

[Ron]

Progressive scan means that the lines of pixels are drawn continuously in one pass -- as opposed to interlaced.

So, if I select "No Fields" as the output, then create a DVD with the resulting DV-AVI, would the video still be BFF or Prog scan?

I ask this because (funny you answered, Steve) I was looking at your video yearbooks and 2 of them were BFF and the 2008 was Progressive scan. My ultimate wish is that I can just use "No Fields" and I would never have to deal with the "jerkiness", as it were, that sometimes occurs.

I made some MPEG-2's a few years ago, not knowing about "Reverse Field Dominance", and I'm noticing the jerkiness a bit in some of these videos. So, conversely, I'm not sure if the fields were reversed automatically (and shouldn't have) when importing the video or if I didn't reverse them and I should have.

It's really hard to understand the whole thing. I've read out there that DVD's are supposed to be BFF, and now you're saying they should be TFF. The ones that I checked were BFF (including the ones that I witness the jerkiness)? Then, I checked a commercial DVD - progressive scan... I'm lost.

[Paul LS]

Hi Ron, I doubt if it will actually export as "No fields". As DV-AVI is spec'd as lower field first I doubt if the settings have any effect... I would expect it to be exported as lower field first.

[Ron]

OK, you're correct as it was easy enough to test. How does that explain the DVDs that have no fields (checking with GSpot) in the *.VOB file?

[Bob]

DVDs use MPEG-2 and the specification allows for either progressive or interlaced.

[Ron]

OK, then how did Steve create a DVD without fields? PE doesn't have the option to deinterlace when making a DVD (maybe used another DVD author?). And I can't tell the difference in quality whatsoever, which is a good thing.

I guess the question is, why use fields/interlacing at all if it's not required? I hope I'm not confusing everyone - along with myself

Thanks for everyone's input!

[Bob]

I don't know how Steve did it, but in Premiere Elements you can simply select the standard DVD mpeg-2 share and under advanced change the field order to none.

Progressive.jpg

[Ron]

Thanks, Bob. But what about DVD export? I know I could run all these tests myself, I just thought some would know off hand (and it's a good discussion for future users searching; I would think?).

When you "share" to DVD, there's no such advanced settings (in PE) and I'm sure the field order is auto (BFF - I'm assuming).

Maybe Steve used a different authoring program for his 2008 video. I just think it would e a good solution to the problem of the jerky video syndrome - simply author the DVD progressive scan vice interlaced. Or am I missing something?

[Steve Grisetti]

Really? My 2008 DVD was progressive scan?

I didn't do anything special with it. Just exported it from DVD Architect, Ron.

[Ron]

We're getting warmer. Did you export from PE in the past (or your recent 2009 yearbook)? Maybe DVDAS creates DVDs without interlacing... or has the option to do so?

[Paul LS]

Ron, Premiere Elements can not export a standard DVD from Premiere Elements as progressive. It will always be interlaced.

[Steve Grisetti]

I see no indication in DVD Architect that the video is being rendered as progressive scan. In fact, the indication is that it won't recompress the video at all -- and that video is being sent to DVD Architect as DVD-quality MPEG2 from Premiere Elements.

So I'm not sure where (or if) it's switching from interlaced to progressive scan.