Enable Multicore preview playback?!?! - who knew?
 

(I posted this in another forum not on this site, and I wanted to see if anyone else knew about this or had experience with it here)

I would like to know how many of you out there knew about this and didn't tell me.

ok, while reading another thread I came upon the statement that you can enable multicore preview playback.

While I do not condone doing this I found some interesting results while doing it.

To enable multicore support you have to access the internal preferences tab, which cannot be done unless you hold down shift when clicking on preferences, then clicking on the "internal" tab, and doing a search for playback will allow you to find it "enable multi-core rendering for playback"

I tried playing back some chromakey footage with it off (default) and on my q6600 I got about 10-11 fps in best full with some SD footage I had laying around, and I had a chromablur on there too.

I also tried making a 7 video plane composite all in 3D space, and then moving that all in a parent 3D track (also in SD) at between 10 and 15 fps.

Then I enabled multicore....

for the first chromakeying, I even resized and set to best full with chroma blur and keying on, and got full 23.976

same for the second, even though I had all that 3D motion, I still had 23.976.

For 3D motion, in 1080HD 24P, I actually get a drop in performance with this enabled ( all gen media ) making it between 3-4 FPS, but with it disabled I get between 4-6FPS after changing the parent 3D motion to make sure it's not using any pre-rendered RAM buffered footage.

For keying and motion blur on some HDV footage I have had laying around, and the multi-core rendering for playback enabled, I got .8-.9 fps. and with it disabled (default), I got 1.1-1.2 fps.

All these tests were done with Best Full scaling on, and simulate and scaling video to fit preview window on from the right click menu on the preview window.

All projects were matched to footage to enable the best performance.

Would be curious to see what others may get, but remember that you do this at your own risk, and while I'm not sure that anything bad may happen, I do not condone mucking about in the internal prefs of Vegas... they're hidden for a reason.

Dave

Yes, Lots to play with in there. But I strongly advise that you back up your system before playing too deeply with any of the internal settings.

David, I have searched and searched for the setting, but keep missing it. Can you give an idea of at what point on the list it is located? Thanks in advance.

I'm in V8, I've been told it's also in 7, but I went back to check, and it's not in 6 to be sure.

there's a search box at the bottom of the "internal tab" and if you type in "playb" it'll be like the 4th or 5th one down and you change it from FALSE to TRUE to change it.

But like was said.

You make these changes **at your own risk**

and it's not suggested you go making changes in there willy nilly

to start vegas out at default BTW - you should hold down CTRL+SHIFT when double clicking on Vegas until the restart at default message box appears.

Dave

Thanks, it seems to be working fine. I'll be working on Monday so I'll get to see it perform then.

Anyone care to speculate why it is a hidden setting and, more importantly, what problems it could introduce, if any?

I can't imagine it'd be to serious, it's not like we're delving into the bios or anything like that, Edward will probably know more about it, hopefully he'll post something soon.

Paul.

It would seem to me that it could not break anything to change a preview setting. If preview were to malfunction at the worst I would think you could close Vegas, open a new instance of vegas with nothing on the timeline and change the setting back.

Generally speaking, the "hidden" settings are hidden for a reason. Perhaps they were added as an idea that didn't get fully implemented or tested so were reset back to their default value and left alone to be resolved in the future. Or perhaps they're still a work in progress.

However, sometimes the hidden preferences DO get moved to the visible preferences. One such preference was the option to dock the timeline at the top OR bottom. It used to be a hidden option - now it's freely available to use. Before becoming visible, there WERE some issues with changing it - mainly in regards to the docking area. These were resolved once it was made visible.

So there ARE some interesting thing there. Just be extremely careful when playing with them, though.

I think this is a wonderful can of worms that David has opened. I'm playing it safe and am sticking to the one setting, but will anxiously await to see what trouble others can stir up playing with them. Great thread David.

It is obvious as has been pointed out by everyone, that one should be careful, that is why I'm not going in there. I have enough issues even when things are going well, I don't need to create new unnecessary ones!

What's the worst thing that could happen ?
All my footage is on external drives so i don't think that loosing footage is a problem, what else could go wrong ? Is it stress on any pc part, ie proccesor or graphics card ?
Or could it be a complete pc crash ?
Could going back to the original settings cure things if something did go pop ?

Paul.

And for those of us at the bottom end, it is there in Vegas Movie Studio 9 Platinum as well.
I type in 'multi-core' in the search box at the bottom and two options get displayed.

'Disable multi-core rendering'
'Enable multi-core rendering for playback'

I suspect that it's hidden because enabling it on a computer with a single core processor might cause Vegas to fail to initialize. It seems that people with true multi-core processors can enable this setting with no apparent ill effects.

As stated on another forum, I have had this switch turned on since version 7a with no ill effects at all. There is nothing to be concerned about.

There are lots of good settings and switches in there to play with and customize.... just back up before you play though, because you're bound to play with the wrong one sooner or later.

Most of the problems that I've ever found in Vegas, were fixable by reducing the number of cores to 1. So this is likely not enabled because of the fact that it would add instability to Vegas Pro of a sort that would be unacceptable.

That's the one you want to change it from FALSE to TRUE - and then hope it all works out :)

Dave

Thanks a million for this tip! I was completely unaware of these "Internal" settings. Will be playing around to see what I get.

I just changed the setting to true and it didn't make any difference to me, in fact i'd say it made the preview playback slightl slower.
I had some 720/50p mxf footage, with setting disabled, preview on preview>full i get the full 50fps, with best>full i get around 7fps with a glow effect added, when i chaged the settings i git about 4 fps.

Quad core q6600, 4gb ram, vista.

Paul.

in some HD content, I have seen that happening, though I find that I hit my peformance peak in a similar situation to yours when I run with 512MB RAM set in the video tab rather than the standard low number that is in there.

Dave

i can't seem to find/see the internal tab
 

Sorry all,

i'm using V.7e, but i can't seem to find/see the internal tab.

i'm holding the shift button whilst pressing preferences... but in the preferences window i don't see an any additional tabs?

anyone else having this problem? Would someone mind posting a small little jpeg?


(computers) the cause of... and solution to... all of lifes problems:)

thanks
mike

should be the top right tab of the window now as long as you click options and then press shift and then click on preferences, and then release - though I warn you that this is not a place to go messing around.

Much appreciated David,

However, at least for me, its not working on V7.0e build 216. Sigh! I tried it on two machines too...

Sucks,

But i did try it on ACID and Sound Forge, and it works on them.



mike

the internal prefs tab isn't happening, or it's not working to turn it on ?

Cheers for the heads up. My previews are stonking now (Q6600)!

Correct, nothing WAS happening.

BUT I just "Ctrl + Shift started" Vegas back to its factory default and then tried again to get the internal tab and... its there now.

I've been hesitant to default Vegas back to its original layout as i had it just the way i want it but the the thought of gaining extra CPU power was too much. So i took screen shots and wrote down notes of my set up.

Anyway the internal tab is showing up now!

Thanks a bunch!!!

I gave it a try and at first I was able to go from full speed at 'Preview Full' to full speed at 'Good Full' but as it played the *.m2t file it started to slow back down again until it was like it originally was.

It is like it gets tired after a while.

Maybe there is a bug in this thing that eventually clutters up the ram or whatever.

Anyway, with that type of unreliability, I turned it back off again.

Danny Fye
VidMus Video - Music Productions

render problems
 

I wonder if this is the reason why we've all had so many problems with rendering using multi-cores, the option is there to use them in the normal preferences, but the registry entry actually has the feature turned off, so theirs some sort of conflict? And this is also the reason why we needed to turn off previews during rendering to help stability as well?

For those who have enabled the multicore preview, are you still rendering with multicores with stability, or do you preview multi, and revert back to single for render? This has been the single most largest bug bear of vegas, and if it solves this problem their will be rejoicing in the streets! No more ripping what little hair I have left out at 3am in the morning!!

regards

Adam

good afternooon,

I turned on the multicore preview and gave it a test run. As someone else noted it seemed to help marginally and then slowed back down after a bit. I disabled it and have left it where it was before.

It would be nice if, as in adobe, you could render your work on the time line and it stays rendered unless you change it, that would expediate things alot when working on large HD projects that have a lot of cc and fx and such, it would also facilitate preview a lot better. Once rendered to mp2 they all play at 29 frames but prior to that it can be dismal, and I am running a 2.6 gh I7quad.

Perhaps there is a way and I do not know about it, would not be surprising.

Vegas has pre-render, though I'm not sure that it's saved with the project file, maybe that'll be something that they can implement in the future, but for the purposes of working on a project that you just leave open, just make sections and then I believe the shortcut is Shift+M (don't quote me on that though). And you lose it if yo move it, etc...

Vegas does have pre render and it IS saved with the project file (.veg). You can note the prerendered sections on the time line by the blue line above the time line. It will disappear if you make a change in the section somewhere. The prerendered on my computer will play back at full fps at best (full). I took a doctored .png photo on the time line and added some color correction and played it at best (full). It played back at about 19fps. I then did a selective prerender (under tools menu) of the section. When I played it back it played at 19fps until it hit the prerendered section and then it went to 30fps (29.97). I saved the .veg to the desktop, closed Vegas and then reopened the project and the prerender was still present.

Terry,


I knew about prerender, did not realize it traveled with the project and thought it was temporary fromwhat I read!! I will try it on tomarrow, rendering a 20 gig br at this time.
thanks for the further information!! the more I learn of Vegas the more i need to know it seems!!

This is not quite right - prerenders are sent to the prerenders directory you designated in project properties, and by default they stay around until you delete them, but they aren't slurped into the veg and don't travel with the project unless you also grab this directory and relink it if you move to another machine.

See page 298 of the vegas 8 manual. By default, these prerenders are saved. There's a pref to clear them when you close the project, and also a menu command to clear them.

But they are a very, very handy tool...

There is a good work around for your render issues that will allow you to render with all 4 cores without crashing:

Sony Creative Software - Forums - Vegas Pro - Video Messages

It was initially worked out for avchd but works with HDV as well.

So far multi-core preview is working awesome... on clips I used to get 10-12fps on, I get a solid 29.97 and see 80-90% CPU usage (q6600 @ 3.0ghz)

Excited to try Vegas 8.1 out (or 9.0) with 12GB ram and an I7 920... @ 3.6-4.0ghz

But won't find out till I decide to spend some moneh...

I am also experiencing a significant increase in preview performance. I've got a quad core @3ghz w/ 8GB RAM.

Thanks!

Unfortunately I discovered very stuttery playback when I turned this on just now. I have an Athlon 64 X2 CPU with 2GB of RAM, so obviously not a big work horse. This system is just slightly slower than my Core 2 Duo system.

I also tested the multicore setting!
PAL DV AVI project, with a simple dissolve between two clips and preview via camcorder DV IN with full(best) setting.

With my E2160 processor i get 17-18 fps with the default settingin the middle of the transition, and when enabled multicore, i get 19-20. So a little increase in performance.
But interesting is how much cpu power is needed for this 2 fps increase:
in first case the 2 core is about 60-65%, and in the second, every core is above 90%
http://www.relaxvideo.hu/false.jpg
http://www.relaxvideo.hu/true.jpg

I think this is the reaseon why not enabled by default the multicore preview.
Maybe the code isnt well written for dualcore support (or buggy?).

Somebody have a config that can play back two stream with dissolve in full quality and full fps on camcorder?

Another settings that i have changed, and like it:

video seekscrub: 16ms (i get very quick response when scrubbing like in Virtual dub!)
meter refresh rate 16ms
event selection outline thickness 3 (easier identify which event is selected)

thx for info!

edited: i also tested without camcorder, only preview on pc monitor
i add a color correction and a title at the dissolve, and when disabled multicore i get
11 fps, when enabled, i get 6! Weird!!