Interlacing Artifacts

[Ken Diewert]

I've tried a couple of times to render downconverted 1080i footage without interlacing artifacts without success. They're not hugely noticeable, but there must be a way to eliminate them. The original footage is XLH1 24f.

I've tried several different render settings and the artifacts are still present during motion shots on the rendered product.

Is there a deinterlacing workflow in DVD Architect? Or third party (Crash??) plug-in.

If anyone can help, I'll post my settings

[David Jimerson]

What are your render settings?

[Ken Diewert]

David,

.avi

First I tried NTSC DV Widescreen 24p (inserting 2-3 pulldown). The rendered project had interlacing artifacts. When I read through the description after, I saw that it was rendered as progressive (which would make sense as it does say 24p)

So I then recreated the whole project (it's only 5-6 minutes - 40 or so edits).

I set my file properties to 720x480, DV Widescreen, PA 1.2121, Lower Field first, Blend Fields

And Rendered as

NTSC DV Widescreen
29.97

This was the only way I could opt out of 'progressive' and preserve the de-interlace settings. However, there were still interlace artifacts on rendered project.

Thanks,

Ken

[David Jimerson]

Well, DV is an interlaced format. When you render with pulldown, you're rendering as interlaced, so some "frames" will show interlace artifacts.

Try rendering uncompressed, 720x480, 1.21, 23.976, progressive. This will give you a pure 23.976 AVI.

[Ken Diewert]

Thanks David.

I'll try it and post the results.

Ken

[David Jimerson]

Well, what are you intending your output to be? If for the web, you're better off rendering to WMV, which is inherently progressive.

[Ken Diewert]

David,

It's just a highlight reel for my sons baseball team. I will out put to DVD.

I tried your settings as a 'custom' setting, and it played back terribly on my monitor. I then tried DV Widescreen 24p and DV Widescreen 29.97 both standard templates.

They seem to be of equal quality. The areas of high contrast (wide beside black - sleeves on uniforms) are demonstrating highest interlacing. Especially where movement is evident. For what I'm doing they will be fine, but I was just trying to resolve the issue for next time.

I likely should have shot in 60i till I get used to the workflow and explore the challenges of 24f in certain situations, such as sports.

Would 60i be less likely to artifact?

Thanks for your help.

Ken.

[David Jimerson]

If that's the case, you should be able to export using the DVD Architect Widescreen 24p DVD template and make a 24p DVD.

What are your project settings?

[Ken Diewert]

David,

My project settings are:

720x480
23.976
1.21 NTSC DV Widescreen
Lower Field First

Render - Quality Good, Gaussian, Blend Fields

[David Jimerson]

Try editing in a 1080i HD project and change the settings to 23.976 and progressive.

If you right-click and select "Properties" on your clips, what does it tell you for stream properties?

[Ken Diewert]

David,

Would I need to to restart the project in 1080i?. This was downconverted footage form the H1.

Clip Stream Properties

720x480x24

F.R. 29.970 (maybe this is the problem?)
F.O. Lower Field
P.A. 1.21
Alpha None

[Ken Diewert]

Double Post... Don't press your TAB Key.

[David Jimerson]

Ah . . . didn't realize it was downconverted. This is all coming together now!

Unfortunately, it looks like there isn't any pulldown to remove, so you can't edit in 24p. Trying to convert it to 24p will create a mess, as I think you've seen. Best just to stay editing in 60i.

HOWEVER, you can try this -- and it'll be a longshot at getting it perfectly right --

Right-click on the clip IN the Media Pool. Choose File Format Properties. A dialog box will appear -- click the checkbox for "Enable 2-3 Pulldown Removal." Don't change the starting frame timecode offset.

This MIGHT make a useable 24p file out of it, but it might not. You can try adjusting the starting frame (by changing the default 0), but it might not be worth the trial and error.

As for project properties, you can always change them instantly on the fly. I think Vegas is the ONLY NLE which allows this.

[Ken Diewert]

David,

I will be stuck with downconverting from the H1 for the near future. Any advice on how best to render (mostly to DVD).

Should I stick with 60i? Is there preferrable project settings for downconverting?

Thanks for all your help.

Ken.

[David Jimerson]

What exactly is it you're trying to achieve? A DVD presentation with no interlace artifacts?

What kind of a TV will you be watching on?