Questions 'solved' by Tech Support

Paul Masters wrote on 4/5/2008, 11:56 AM

I asked a number of some what related questions of Tech Support and nearly all of them were 'solved' with out an answer.

Perhaps someone here can help me understand these a little better. I have modified them a bit and include Sony response that was given.

***

I see the Deinterlace method has 3 choices.

None is obvious.

Blend fields says, ‘Uses contents from both fields and works well for high-detail, low-motion video'.

Interpolate says: ‘Uses a single field at a time and works well for high-motion, low-detail video.'

How do you deal with both video types in one project / clip?

I have discovered that HDV, at least with the camera I use (Canon XHA1), blurs when there is motion by the subject or camera movement.

As I have both high detail and ‘high motion', which setting would be best for this project?

Sony reply: You will have to pick one of the other for your project. Experiment and see which one works better.

Any better thoughts?

***

How does the project properties settings effect rendering?

That is, changing the template or frame size effects the preview window, but does it effect how the output is rendered?

Are the rendering settings the only thing used when rendering?

What, if any of the project properties are used during rendering?

What happens if the field order is changed? That is, what if the media has upper field first, but the project properties says ‘none'? Is the deinterlaced method used to create a progressive frame? And how does this relate to the field order on the rendering video tab?

***

When submitting a previous question, I was pointed to some possible solutions. While not what I was asking about, one looked interesting so I read it. Unfortunately, it confused me more than it helped.

It said that the Vegas and DVDA projects and rendering should be lower field first. I checked and sure enough the rendering template said lower field for DV, and both the DVDA templates have lower.

However, the HDV 1080 60i, which is defaulted to as my project is 1440/1080 says upper. My project with the HDV 1080-608 (1440x1080, 29.970 fps) template says upper and my media says upper.

So, what should it be?

And will this effect the quality of the DVD video?

Sony reply: If you are going to render a project for DVD, then you will want to set the project properties template to "HDV1080-60i". When you render the project, chose MPEG2 and choose the template "DVD Architect NTSC Wide screen Video Stream". Upper field and lower field options will be calculated by the software.

If it will be ‘calculated by the software' then why are there options to change it in the project properties, media properties and render template?

And, what ‘happens' if they are different?

***

I have video created with Canon XHA1 - HDV 1440/1080 29.970 interlaced.

I realize that I can't make an ‘HD' DVD so have to use 720x480. Or is it 704x480? DVDA has both.

I and others have a wide screen TV, while some have a standard 4.3 TV.

What settings should I use in Vegas and DVDA project properties and which rendering template and what changes need to be made to what to create a DVD that will play correctly on both?

I have done tests with DVDA NTSC which appears to letter box the image even on my wide screen TV, and with DVDA NTSC wide screen, which seems to be OK on my wide screen but looks ‘narrow' on the standard TV.
What do I need to do to get all the image on the screen on both types of TV?

Do I have to make two copies - one for 4.3 and another for Wide screen?

***

While working with a plug in (Mercali), and stepping through the clip frame by frame, I noticed a lot of interleave artifacts - that is the ‘Venetian blind' effect.

Is there a way to minimize this?

Would changing the Project Properties frame order to none, for progressive, help? Or would that reduce the resolution?

What about the Deinterlace setting?

Thanks for your patience with so many questions.

Any help will be appreciated.

Paul Masters

Comments

farss wrote on 4/5/2008, 1:55 PM

1) No better thoughts unless you need to de-interlace. You would only need worry about this setting if downscaling or converting to progressive. In the later you'd do better using a smart de-interlacer.
2) Mostly not at all unless downscaling.
3) Vegas handles changes in field order, you don't need to worry about it. Just stick with the standard templates or you're very likely to really make a mess of things.
4) Use 720x480. HDV is 16:9. Always use 16:9 or "Widescreen". It will play correctly in correctly setup DVD players and TVs.
5) When working with interlaced footage you will oftenly see interlace artifacts in the preview monitor. They're not real, ignore them unless you see them in the rendered output.

Bob.

Laurence wrote on 4/5/2008, 6:05 PM

Be aware that in order to downrez from HD interlaced to SD interlaced, you need to select a deinterlace method even though you aren't actually deinterlacing. You can select either method in this case since when downrezzing from interlaced to interlaced there is no actual deinterlacing,

I have no idea why, but if you downrez HD interlaced to SD interlaced and have no deinterlace method selected, what will happen is that Vegas will resize the interlaced comb edges which looks really terrible on any fast motion.

In this case, selecting either deinterlace method will cause Vegas to separate the even and odd fields, resize them separately, then fold them back together by even and odd lines at the new size.

If you are downrezzing HD interlaced to SD interlaced to make an SD DVD, this is exactly what you want to do.

Another situation is that you want to downrez an HD interlaced project for computer or Internet playback. In this case you want to render to a progressive format at the new smaller size.

In this situation, the deinterlace method you choose will have an effect on your final output.

Blend fields will double both the even and odd fields which are a sixtieth of a second apart and blend them together. This will give you a bit of a double image on fast motion that is both good and bad. The good is that you are not throwing any information away and that the motion will often look smoother and noise and graininess will be masked a little. The bad is the doubled image isn't quite as crisp or clear.

Interpolate throws one field away (either the odd or even lines). It then interpolates points between the remaining half of the lines so as not to get "jaggies" or staircased artifacts on diagonal vertical lines.

Since you are usually deinterlacing and downrezzing at the same time, "interpolate" is often the better option since artifacts introduced by interpolation isn't a problem when you are reducing the resolution to half or less that of the original.

Another deinterlacing option is turn the deinterlace option off and reduce the resolution to exactly half of the original. What this does is drop every even (or odd) line and give you an absolutely perfect deinterlace.

Laurence wrote on 4/5/2008, 6:19 PM

If you want to deinterlace by reducing the resolution by half, the dimensions you want to render to are 960x540 pixels. This is a really cool number because it is the same as the resolution of the sensors on a lot of HDV cameras. For instance a Z1 or FX1 has three 960x540 sensors. These are offset a little to give you 1440x540 resolution, but even so, there is still some interpolation used to give you the 1440 resolution from the 960 sensors.

960 x 540 renders from HDV footage without a deinterlace method selected give you progressive renders that look very, very good.

I used to use 960 x 540 for my hd DivX renders that I put up on the now defunct Stage6.com.

I also use 960 x 540 renders to feed On2 Flix to generate flash video at various resolutions.

Paul Masters wrote on 4/6/2008, 12:09 PM

Thanks for all the comments.

Please see my reply (to my self <g>) in the AVI Interlace thread.

I made some discoveries (at least for me) and would appreciate your comments on them.

Note that I am not trying to down size the resolution - well, I guess I am in one way as I can't (yet) create a 1440x1080 disk - so it has to be downrezed to 720x480 for DVD.

Thanks.

Paul Masters