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Ivan
01-15-2005, 01:00 PM
Here is the scene:

RTV background video playing from Array
PNG image overlayed with a border
Both are resized and have motion

This plays back with no problem.

Now I add a shadow to the PNG overlay and blur the shadow.

It will not play back smoothly and it does not seem to render. The green light doesn't go on and when I open Task Manager the CPU Usage never goes over 34%.

It seems that the drives are fast enough to play the video layers in real time because it does play back fine before I add the shadow. Therefore the problem comes in that the shadow has to be calculated and drawn correct? If so, why are the CPUs only running at 30 - 34%. It has lots of headroom here. I tried widely varying settings (from 10.00 to 4.00, I'm running a dual 3.02 with 2 gigs of memory)for the CPU in Prefs and nothing changed.

Any Ideas?

Thanks,

Ivan

Ivan
01-15-2005, 01:08 PM
PS. I just did another test and I noticed that without shadow enabled I actually get up to 54% CPU usage when I first hit play. Add Shadow and blur the shadow and CPU usage never goes over 34%.

Ivan

ted
01-17-2005, 11:05 AM
What types of drives?
How full are they?
Have they been defragged recently?
Will it play using force render?

I know the shadow adds to the processing, but, your system should be able to handle this and more.

Ivan
01-17-2005, 05:40 PM
It is not a drive issue or a drive performance issue or a machine issue. It has to do with the way VT4 SP1 handles shadows and Blur on shadows. If you want to see this for yourself, try this:

Place a video clip on the timeline
Place a CG PNG on the Timeline, set it to overlay

Hit play and it plays fine.

Now put a shadow on the CG and again it plays fine

Now Blur the shadow by 10 or 20 on both the x and y and it will not play.

When I am experiencing rough playback I look at my Task Manager and the CPU usage has not increased to account for the increased demand. In fact when I turn shadow off and hit Play, the CPU initially bounces to over 50%, when Shadow and shadow Blur are activated, CPU usage never gets near 50%.

If this was a drive problem I would not be able to play back the first scenario because it is using the same image and the same clip. This is an issue where VT is not utilizing the total available CPU. I have tried to adjust the CPU setting in prefs from .20 to 10.00 to see if that matters, it does not.


Please try this on your system and tell me the results.

Thanks,

Ivan

ted
01-17-2005, 06:33 PM
I just tried your test and it takes a force render to make it play OK.
Not sure it's a bug, but you might e-mail Andrew. He might be able to have the code re-written so it will work easier???

Ivan
01-17-2005, 09:32 PM
Thanks for verifying this at least I'm not totally nuts. :)

Ivan

Jim Capillo
01-17-2005, 09:51 PM
Thanks for verifying this at least I'm not totally nuts. :)

Ivan

Doing the same on my system and not even a force render will make it play smoothly. I need to render it out as a new clip.

Seems like you're on to something...... I've been screwing with the prefs for a week with this one project that will not play smoothly no matter what. Borders and shadows abound........

Ivan
01-17-2005, 10:47 PM
Borders do not seem to cause a problem for me. I can do almost anything but put a shadow with a blur or enable ISS and VT Plays fine. If I do either of those I have to render.

Ivan

Jim Capillo
01-18-2005, 05:10 AM
Borders do not seem to cause a problem for me. [snip]
Ivan

Well, they may not be a problem here either, Ivan. Just saying that this particular project that is giving me fits has borders as well as shadows. If I have time today, I'll try and shut off things one by one to pinpoint the cause.

It was pretty embarrasing with the client sitting there and the project wouldn't play at all. :(

Ivan
01-18-2005, 06:39 AM
I know what you mean especially when you tell them how much quicker it is to edit when you don't have to render...

Ivan

Ivan
01-18-2005, 10:02 AM
Testing some more and it does render without a force render and when the green light goes on it plays back fine using only about 14% of CPU. Paul said his will bounce to 75 -95 percent. I'm wondering what's up with my machine once again. If I could get 75% out of mine it would just play back without rendering.

Ivan

Jim Capillo
01-18-2005, 12:11 PM
Testing some more and it does render without a force render and when the green light goes on it plays back fine using only about 14% of CPU. Paul said his will bounce to 75 -95 percent. I'm wondering what's up with my machine once again. If I could get 75% out of mine it would just play back without rendering.

Ivan

I'm getting almost the same results as you. My CPU is at 13% with the stutters (shadows turned on).... shadows off, stutters gone.

I've boosted my VTEdit PCI bus to 10 and moved the SCSI RAID up to 90mbs..... that seems to get the quickest green light. Try that.

No matter the green light, as soon as the playback encounters a cg (png set to high, no ISS) that has the shadows on, the green light goes off and the stuttering starts. CPU usage remains at 13% or so.

There seems to be a problem in shedding more of the load over to the CPU's when needed. It just doesn't seem to be happening. At least localized with shadow rendering.

Any ideas?

Amanda Lynn
01-18-2005, 02:46 PM
has this been solved yet? i've got this exact problem on my computer (and also in front of a client!) - using .jpgs with and without shadows and minimal movement. can someone tell me what the advantage is to this pre-rendering instead of us just force rendering when needed?

:confused:

Jim Capillo
01-18-2005, 03:33 PM
has this been solved yet? i've got this exact problem on my computer (and also in front of a client!) - using .jpgs with and without shadows and minimal movement. can someone tell me what the advantage is to this pre-rendering instead of us just force rendering when needed?

:confused:

Well, you should try using png's, not jpg's (Newtek's recommendation).

What is your host computer config? Mine is a dual Xeon with 2.8 ghz..... and SCSI RAID. 2 gig RAM. Obviously, less powerful computers will have a much harder time than the powerhouses.

Rendering to a new clip will eliminate all possibilities of stuttering.

Pete Draves
01-18-2005, 09:10 PM
the projects that do not play without a background render on vt4 used to play fine with out any render on vt3.
it seems that 4 to a step backward when a lot of sizing and positioning is used.
almost looks like the background render is a kludge.
Pete

Amanda Lynn
01-20-2005, 05:21 PM
Well, you should try using png's, not jpg's (Newtek's recommendation).

What is your host computer config? Mine is a dual Xeon with 2.8 ghz..... and SCSI RAID. 2 gig RAM. Obviously, less powerful computers will have a much harder time than the powerhouses.

Rendering to a new clip will eliminate all possibilities of stuttering.


My Tech Service guru says that the computer I work on might not be fast enough... it's (let's see if i write this out right) Intel XEO with 1.80 ghz & 1 gig RAM.

I'd also rather not consider having to re-edit my project. I began it in VT3, but it's been so ongoing that it's transferred to VT4. I experimented with transferring a few .jpgs that i've got in my project to .pngs & then replacing the jpgs in the project with the pngs...but that didn't work. Jeff (guru) and I think that i should just work on my project section by section, render them to .avi files, then compile those to make my project.... and from now on work in png format.

Wish me luck. Or please give me another idea!!!

RayLarson
01-21-2005, 06:23 AM
We also have Dual 1.8 Zeons with 1 gig of Ram and have had to reinstall T3 since we could not get acceptable performance. T4 needs more horsepower than those processors can deliver, at least in our situation. :(

JonCrowe
01-21-2005, 03:13 PM
the projects that do not play without a background render on vt4 used to play fine with out any render on vt3.
it seems that 4 to a step backward when a lot of sizing and positioning is used.
almost looks like the background render is a kludge.
Pete


I agree with Pete. It seems the VT3 could play more without rendering/stuttering. I know it's been talked about many times here, but it seems like people are still having issues with the green light/background render. Are most of you using the auto-config settings or the trial and error method when setting up the background render settings?