Comments

LoTN wrote on 3/7/2010, 9:53 AM
Are all of you happy with this stutter-behavior? Or am I the only guy whining and ranting about this?

You're not alone. While I accept stutter during transitions and also with cpu consuming plugin chains I am still trying to figure out how it comes that even a single track 720p project displaying a spinning letter from left to right does stutter even with RAM renders. It also makes me toughtful when rendered to file it stutters too.

My system is a dual core laptop with 4G ram, 7k2 disks running seven 64. I can play HDV smoothly, my little bit of video with that spinning letter will stutter.

SCS support was unable to reproduce the issue. I worked on it and just came to one interesting observation: if the clip duration is low I get stutter, if raised enough to slow mo the track motion between the only two keyframes then stutter disappears.

Finally, I gave up trying to fix it.

UlfLaursen wrote on 3/7/2010, 10:39 AM
I see it too, and hope it will be fixed soon.
I am with you Lars, Vegas is such a great application, and you can do so much great stuff so easy and in no time.
I use SHIFT+B a lot on transitions and effects, especially on HD projects.

/Ulf
LarsHD wrote on 3/7/2010, 11:04 AM
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Coursedesign wrote on 3/7/2010, 11:23 AM
Subpixel rendering.

Without this feature, the renderer has to truncate to the nearest whole pixel in steps.

Adobe has it, Avid has it, Apple has it. Sony must have thought that you should go to After Effects for this.

You can try tinkering with different rates of movement until you find one (or in this case, two: vertical and horizontal) that doesn't jump. Also solvable with a bit of math.
Coursedesign wrote on 3/7/2010, 11:27 AM
Here's a good Wikipedia article on subpixel rendering.

Note especially the example text animations on the left.
LarsHD wrote on 3/7/2010, 12:17 PM
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LarsHD wrote on 3/7/2010, 12:31 PM
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Coursedesign wrote on 3/7/2010, 12:48 PM
Your output frame rates can be be anything you want if you're outputting to the web say, where there are no fixed frame rates.

TV and film has 23.976, 24, 25, 29.97, etc. and you can't avoid those.

So, what can you change?

You can change the rate of pixel movement in your animations to be a multiple of the frame rate.

In your case, it sounded like this would need to be handled for both vertical and horizontal movement.

It doesn't matter whether your relative movement is caused by zooming, lateral movement or vertical scrolling. It's all the same.

Are you saying that VLC and WMP are playing this back perfectly?

If so, are they playing back Vegas-rendered footage that looked wobbly in Vegas?

What frame rate was used?

The players could potentially use frame interpolation to add subpixel accuracy of movement on playback.
LarsHD wrote on 3/7/2010, 1:07 PM
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Coursedesign wrote on 3/7/2010, 1:36 PM
Well, I am beginning to to think that we are talking about different things.

Here are my new assumptions about what you are saying:

1. Your test project is 23.976 progressive.

2. It stutters when viewing it in Vegas' preview.

3. If you render your Vegas-stuttering project to an AVI or MOV file and play that file in VLC or WMP, everything looks fine.

If those assumptions are correct, you have a situation that is common to all NLEs (although Avid does the best job of hiding it): you can't judge much of anything in the "viewer/canvas," this is just a simplified periscope with other design objectives.

If you are going to work with troublesome footage, you need to use a proper video output card and a broadcast monitor or a TV. For progressive footage, this means an AJA card (or BMD depending on Vegas version), and using an output signal that is not a "computer" output signal.

(If you want to do true monitoring to broadcast standards, you need a special monitor such as the HP DreamColor ($2K street), and even then there is much work left to do. See this article for more on this.)

LarsHD wrote on 3/7/2010, 2:26 PM
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Coursedesign wrote on 3/7/2010, 4:04 PM
I've been using BMD Decklink Extreme cards for input and monitoring for four years.

You didn't say if my assumptions were correct, that is important for determining what will work for you.

If outside players (VLC, WMP, ...) do not stutter, but Vegas does, then a card hooked up to a broadcast video monitor (or a TV) should take care of the display issues.

If you're using Vegas 9, you may be better off with an AJA card, although I have been worried about Vegas' support for professional I/O cards, as the support seems a bit wobbly. You need to investigate this further.

Not many people in this forum use anything else but regular computer monitors hooked up to a regular computer graphics card using signals that are very different from non-computer video formats in several ways. Format translation can handle some of the issues but not all, so critical monitoring is not possible with say an 8800 card.
LarsHD wrote on 3/8/2010, 2:43 AM
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Coursedesign wrote on 3/8/2010, 9:01 AM
I'm on deadline today, but will contact you offline to give you my e-mail address.

There are many more complications when you're not using a pro monitor.

Let's say you get a nice HDTV to use for monitoring.

Most TVs overscan whether you want that or not.

So you get one where this can be turned off.

Then you feed it your 1920x1080 signal.

Umm, that is promptly uprezzed to 1920x1200, because that is the native resolution of the screen.

Or you feed it your 960x540 signal, which is then uprezzed to 1920x1200.

Either way you may experience a long list of possible artifacts, including stutters created by the TV.

You have to look carefully for a screen that has 1:1 pixel setting, i.e. that will show a 960x540 picture in a 960x540 pixels.

Without that you have no way to know what is causing the artifacts.