Problems rendering letterboxed video

Finster wrote on 12/6/2002, 10:17 AM
I did a trial letterbox rendering of a 40 minute widescreen project and hit a couple of snags:

Whenever there was significant motion, a pan or tilt in the video, some raster-like artifacts appeared...horizontal lines runing across the image. Quality was set to "best." Do I need to turn on deinterlace or some other setting?

30 minutes into printing out the rendered letterbox version the video just did a freeze-frame in the middle of a shot and stayed frozen for the rest of the show while the audio continued. I was watching the rendering preview and saw the final shots being processed, but even if I play from the timeline that same shot freezes 'til the end. The green bar at the top indicates the entire piece is rendered. I thought it was a bit odd that the status window said something about "70 out of 73" being complete when the print-to-tape window popped up. It must not have really been finished? How do I un-render and then re-render just the last 10 minutes if this happens again?

Thanks in advance,
Finster

Comments

jetdv wrote on 12/6/2002, 10:42 AM
Apparently you had no additional edits thru the end. The window ONLY changes in sections it must RENDER.

So, your additional steps would be:

71 = Convert audio to .w64
72 = Print to tape
73 = Clean-up aftwards


These are always the last 3 steps.
Finster wrote on 12/6/2002, 11:05 AM
Thanks Jetdv, very useful information since now I won't have to wonder about those "missing" three steps ever again.

But any idea why I would get a ten minute still-frame? There were at least thirty shots and maybe 10 dissolves that aren't showing up.
jetdv wrote on 12/6/2002, 11:18 AM
How long were the dissolves? The display is only updated when rendering a frame that ends in "0" or "5".
Finster wrote on 12/6/2002, 11:54 AM
You lost me...I think we're talking two different subjects or that last critical brain cell in my cranium just died. What display are you refering to? How does a frame end in zero or 5? Do you mean a 20 or 25 frame dissolve as opposed to maybe a 23 frame dissolve?

I'm talking about my rendered video freezing 30 minutes into a 40 minute show. It freezes in the middle of a shot with no associated effects. I can see all the individual shots (picons) still sitting there on the timeline, but when I play or cursor over them I get the still frame. I'm sure I can revert to the previous, unrendered version and try again, but it took all night to render so I'm looking for a reason.

And thank you sincerely for your help, but I'm not quite following you. My bad, I'm sure.

Finster
jetdv wrote on 12/6/2002, 1:02 PM
You are correct - we were talking about two different things. When rendering, the display updates every 5th frame that requires rendering (technically, just the frames that end with 0 or 5). I was referring to rendering and NOT playing back from the timeline.

Without seeing the original project, I'm not sure I could diagnose why one frame, after rendering, would repeat through the end. I can think of several things that could cause it but it would be difficult to pin down without looking at the original .veg file.
Finster wrote on 12/10/2002, 9:45 AM
Just for the sake of closure on this thread, here's what happened next:

I noticed that the free space on my media drive (external 80gb firewire) had gotten pretty low without my noticeing, down to about seven gigs. This seemed a likely source of problems,so I dumped some files and recovered another 10 gigs or so. Then defragged the drive. Due to some unknown curse of the computer gods, this caused a huge performance drop rather than a gain, and playback from the timeline dropped to about 12 frames per second, on the preview screen as well at external monitor and the same for Print-to-tape mode. I also experienced a number of lock-ups where I had to CTRL-ALT-DELETE out of Vegas.

However, I was able to render the program out as a widescreen avi and print that to tape from a new timeline without any problems at all. All the material on the external drive seems to be just fine. (Whew!) Letterbox video is still looking ugly, full of horizontal lines, but I'll deal with that later.

Truth be known, I've been having some troubles ever since I switched motherboard and chip a couple of months ago, so I've decided it's time to reformat the system drive and start from scratch. Hate to do it in the middle of a project, but so it goes...

Wish me luck,
Finster

BillyBoy wrote on 12/10/2002, 10:10 AM
For what it is worth... I'm using Windows XP and as most of you probably know, once you start to render a project Vegas will "hog" most system resouces. On my PC anywhere from 88-96% of clock cycles according to Task Manager.

The problem is if you want to use you PC for something else during one of those marathon renders that take many hours your system is less than responsive and prone (due to Windows) to have other applications freeze, lock up or other nasty things can happen.

While Windows will take some resouces away from Vegas to allow you to do other work and it doesn't hurt the render, doing so (at least for me) greatly increases the risk of hangs or a freeze.

Am I alone in experiencing this?

If others see this, what fix if any have you used? I know, use a seperate PC for rendering. I was one of the first to suggest that long ago, but sometimes I got two or three renders going at once and need to use my main PC for rendering while doing other work.