Virtual Dub downconverting question

[DMS Video]

Today I ran into my first problem using Anton's Virtual Dub downconverting method. I have a six minute HD project with TONS of titles. I'm in New York (so I'm NTSC). According to Anton's workflow (option #2) I should use 720x480. I realized in the past couple of downconverts I used 720x576 and the results looked great. However none of those projects had any titling. Today I used 720x480 and the titles didn't look right (I used Quick titler). The fonts look okay except there are small random dots on many of the letters. That's the best way to explain it. So I went back to the original file and went through the entire workflow again using 720x576 and the results look great. Not totally perfect on the motion of the titles but very close. Should I stay with the 720x576 or could there be some other problem?

[antonsvideo]

720x576 is for Pal, where re you sending the DVD's?

if USA, use NTSC, 720x480, it should look fine providing you open the resulting file in a 720x480 DVD preset (not D1 preset or DV preset)

D1 in NTSC = 720x486 so no good for DVD

[DMS Video]

Anton,

Thanks for the reply. I'm in New York and all the DVDs are for the U.S. I just watched the downconverted DVDs on Multiple TVs (both 16x9 and 4x3) and the version that was 720x576 looks great. I know it's Pal but the 720x480 is giving me problems. I just took a look at my current project settings and in the description it says...

Hardware: HQX-E1
Video
Frame Size: 720x480
Frame rate: 29.97
Field Order: Top Field first
Audio
Rate: 48000Hz
Channel: 8
Setup
Render format: Canopus HQ standard
Over scan size: 3%

To create the dvd I simply clicked "burn to disk" from the timeline. The settings I see once that program opens is 16:9 720x480 8.0Mbps

I'm not sure why it's working this way (720x576) and not working the way it should (720x480). I have a very critical eye and won't accept an encode that doesn't look correct so I'm at a loss to understand what's happening with this entire scenario. Ideas?

[antonsvideo]

does it look ok while playing the VD clip on the timeline?

[DMS Video]

Anton,

It looks fine. I rebooted the computer and created a brand new SD preset (720x480 DVD) and just downconverted yet again. I noticed when you're using 720x480, right click, choose properties, choose aspect ratios, the only 16:9 option is 1.2000 (16:9). I tried this combination. The resulting DVD plays on my 16:9 lcd full screen but also letterboxed. I've seen a few movies like this. The image in not squeezed but very much rectangle-like (skinny). When I compare this to the 720x576 version I still think the "576" version is correct. It plays full wide-screen on my 16:9 lcd and is letterboxed on my 4:3 tv. Just as you would expect. I noticed on my 720x576 renders that there is a different Aspect ratio option, 1.4222 (16:9) that works great and is the same selection you used (even though you're PAL) in your web site tutorial.

After going back I realized the previous downconverted DVDs I created were from a 720x480 project preset where the output format was 720x480 59.94i 4:3 (DV). I don't know if it matters as this is getting complicated but as per step number 6 in your process I always select the frame rate as 29.97.

[antonsvideo]

720x480 59.94i 4:3 (DV) would have been your problem

720x480 59.94i 16:9 (DVD) will be perfect

when you right click VD clip on timeline, set to fill preview window, 16:9 should do it

if not, there is always the layout tool, to select fit width or fit height

[DMS Video]

What you're describing makes sense and I will try it when I begin editing again tomorrow. I just don't understand why I AM getting good results with the parameters I'm using. I think I'll start fresh again tomorrow and see what happens.

Cheers

[antonsvideo]

I do many jobs in Pal and NTSC, so far I have not experienced any issues with 720x480

[DMS Video]

Update: Anton,

I spent time going over the entire workflow using 720x480. I am now able to make it work successfully. However, there still must be a bug in the system somewhere. I created an NTSC project using 720x480 and there still is a problem with the font (the video clip itself is fine). I'm convinced it's a bug, probably with that particular font. If I use 720x576 the font is fine and actually the project itself looks fine. I'm not going to try to figure out or understand why that is but those are the results after many attempts and a lot of coasters. Thanks again for your help.

[antonsvideo]

what font are you using and are you using TMPro or QT?

[DMS Video]

In this project I used both TMPro and QT. The problematic font is in QT. It's Ashley Crawford MT Light.

[antonsvideo]

I don't have this font, is it a real thin one? If so, I usually stay clear of them

what is the exact artifact you see when the font comes on after encoding

[DMS Video]

It is a thin font but I made it bold. It's a good looking font. The best way to describe the actual problem I'm having when using 720x480 is the text has a lot of random small dots all over the place. I've never seen anything like it. It doesn't happen if I use 720x576. I just went through the entire process again both ways, 720x480 AND 720x576. As much as I know it's not supposed to work, the 720x576 in NTSC looks much better, with no artifacts, so I decided to go ahead and finish this project and burn a couple of hundred dvds.

Cherrs

[plekkie]

I have had problems with artefacts in text from QuickTitler, see this thread http://ediusforum.grassvalley.com/fo...0609#post80609.

Does this look like your problem? To me it happened only after applying the sharpness filter (last step of "Anton's VDub method"). I was using 720x576 (PAL) though.

[DMS Video]

plekkie,

Thanks for your reply. That's exactly the same problem. I tried everything to fix it. I ended up using the PAL settings even though it's NTSC. It doesn't make sense to me but for some reason it works and the aspect ratio is fine. I will try removing the sharpness filter and see what happens. Cheers.