Preview Video Stalling on complex transitions - How to fix?

**worddigger** · 06-08-2012, 08:23 AM

I recently upgraded to Vegas Pro 11. This required upgrading my editing terminal's operating system to Windows 7 (32 bit). Although the preview video monitor runs smooth on simple camera footage and simple cuts and fade transitions (HD 720p), the preview monitor seems to stall and jump (stutter, you might say) and skip lots of frames when doing more complex transitions and effects like dissolves and video over video mixing. Of course, this is just a preview quality problem, as the rendered product is fine. But it bothers me because it makes adjusting edit points a pain working in real-time with the timeline because I can't always see synced video and audio in real time in the preview monitor.

My first inclination was that this is a hardware problem (not powerful enough to handles the new Vegas 11 platform). Instead of buying a new terminal, I figured it would be cheaper to upgrade what I have. After all, it is a quad 4 processor terminal. Here is what I did: First, I upgraded my Windows 7 OS from 32 bit to 64 bit, so the new Vegas could make better use of the available RAM. I also increased the RAM from 4 gigs to 8 gigs. I also ungraded the graphics card from a NVIDIA Quadro series (32 bit) to a NVIDIA GeForce GTX 275 (64 bit).

Of course, everything now runs faster than snot on a Teflon doorknob. The Vegas program also loads faster and has much more overhead to work with, but this did NOT cure the preview stalling problem.

This MUST be a software issue. QUESTION: Do any of you Vegas using guys have any suggestions on how I might tweak the Vegas Pro 11 system to improving preview playback performance?

Thank in advance.

**Midnight Blue** · 06-08-2012, 09:19 AM

Hi Digger, I don't use 11 but I presume it's pretty similar to 10. The only thing I've found works is to either lower the preview quality or pre-render the clip. Now that you have more RAM you could try experimenting with the Dynamic RAM Preview setting, on the Video tab of the preferences, to see if that helps but I've never found that it does.

The only other advice I can think of is to make sure you have the most up to date version of the 64bit build of Vegas.

Sorry if that's rubbish advice I'm just not a Vegas settings expert.

**Grazie** · 06-08-2012, 11:01 AM

Originally Posted by Midnight Blue

Hi Digger, I don't use 11 but I presume it's pretty similar to 10.

Your presumption is correct. However . . . .

Originally Posted by Midnight Blue

The only thing I've found works is to either lower the preview quality or pre-render the clip. Now that you have more RAM you could try experimenting with the Dynamic RAM Preview setting, on the Video tab of the preferences, to see if that helps but I've never found that it does.

The DRP needs to be used in conjunction WITH the Build DRP or, SHIFT+B. Look, just setting aside more RAM to Preview will not do anything. In fact, it will do something detrimental to Real Time Previewing. And that is this: Vegas has always been dependant on the CPU for getting Real Time Previewing. The faster the CPU, the better. The CPU will use RAM to deal with the workings of Vegas and all your other system RAM requirements. Denuding this process of usable RAM - setting aside RAM for DRP can only work against getting better Real Time Previewing, through the CPU. Added to which, allocating RAM and then NOT using Build RAM Preview is illogical and detrimental to the CPU getting a chance to process all your trannies and CC and so on and so forth. Hence your observation that setting RAM for DRP is counter. If you don't SHIFT+B, I'm not surprised!

Originally Posted by Midnight Blue

The only other advice I can think of is to make sure you have the most up to date version of the 64bit build of Vegas.

Always a good idea. However. . . . .

Now that the SCS engineers have gotten busy with implementing some of that lovely Graphics Card RAM, we are now in the realms of the truly "Dark Arts". Consequently, there has been much buzz and discussion about either switching on GPU acceleration or switching it Off. People are weighing up the benefits and downfalls of both. And yet again, there will only be some OFX plugs that can themselves make USE of all that lovely GPU territory. Not straightforward, and as a result, common sense here is at a premium.

Here's my take on it all:

1] For "Suck n See" Previews I allow Vegas to monitor, using the "Adjust for Optimal Playback", for what I've got, and let it be.

2] For anything more intensive that requires my scrutiny I'll do a SHIFT+B and have something like 200mb aside in the Prefs Settings for it. Going above 1000mb tends to bring VEGAS, on my 16gb PC to its knees.

3] For any GREATER scrutiny and Q&A than 1] and 2] I use Shift+M to Prerender a Selection and use the the blisteringly fast Lagarith CODEC as my Weapon of Choice!

4] When I'm confident that the Plugs I'm using CAN make use of GPU accel then I'll invoke that. Along with 3] this CAN be stunningly fast, but my results are truly dependant on my setup, which, by definition wont be yours or Midnight's.

Finally, and this ain't a cop-out, you'll need to check out these 4 alternatives, make mental or written notes as to what gets you to "Route-ONE" and be aware that if SCS's welcomed, recent responses are anything to go by, is that these improves WILL be becoming thick and fast in the months to come. We all need to be on out tip toes to get up to speed.

OK, the future could be rosy, but getting to there from here will require a wee bit more than just doing the editing.

I really do hope that some of what I've written here will be of benefit. This has been my experience, and when I read people struggling - as do I - I'm wanting to pitch in and give some potential avenues to explore.

.......

**worddigger** · 06-08-2012, 12:32 PM

Originally Posted by Midnight Blue

Hi Digger, I don't use 11 but I presume it's pretty similar to 10. The only thing I've found works is to either lower the preview quality or pre-render the clip. Now that you have more RAM you could try experimenting with the Dynamic RAM Preview setting, on the Video tab of the preferences, to see if that helps but I've never found that it does.

The only other advice I can think of is to make sure you have the most up to date version of the 64bit build of Vegas.

Sorry if that's rubbish advice I'm just not a Vegas settings expert.

Midnight,
I have also tried increasing the the DRP in the 'Video' tab and, like you, did not see any difference. And, if read the next poster after your's message, that was to be expected. At least I know that I am not alone in experiencing this issue with Vegas Pro. Hell, I was even contemplating going to a MAC and Final Cut, but I'm too old to make that drastic of a change.

**worddigger** · 06-08-2012, 01:14 PM

Originally Posted by Grazie

Here's my take on it all:

1] For "Suck n See" Previews I allow Vegas to monitor, using the "Adjust for Optimal Playback", for what I've got, and let it be.

2] For anything more intensive that requires my scrutiny I'll do a SHIFT+B and have something like 200mb aside in the Prefs Settings for it. Going above 1000mb tends to bring VEGAS, on my 16gb PC to its knees.

3] For any GREATER scrutiny and Q&A than 1] and 2] I use Shift+M to Prerender a Selection and use the the blisteringly fast Lagarith CODEC as my Weapon of Choice!

4] When I'm confident that the Plugs I'm using CAN make use of GPU accel then I'll invoke that. Along with 3] this CAN be stunningly fast, but my results are truly dependant on my setup, which, by definition wont be yours or Midnight's.

Finally, and this ain't a cop-out, you'll need to check out these 4 alternatives, make mental or written notes as to what gets you to "Route-ONE" and be aware that if SCS's welcomed, recent responses are anything to go by, is that these improves WILL be becoming thick and fast in the months to come. We all need to be on out tip toes to get up to speed.

OK, the future could be rosy, but getting to there from here will require a wee bit more than just doing the editing.

I really do hope that some of what I've written here will be of benefit. This has been my experience, and when I read people struggling - as do I - I'm wanting to pitch in and give some potential avenues to explore.

I greatly appreciate and thank you for your input. I will try to digest all the information you have outlined to see what works best.
Again, thanks.

**vidmanners** · 06-09-2012, 12:30 AM

VS user, but understood from Sony creative webinars that pro11 will use the graphics card for preview and renders . . . indeed the "demo" indicated it was nearly 3x the speed of Pro10.
+ Look at Vegas site FAQ's etc . . . yr Pc reads it's pretty fast.
Sony Tutorial has some test-footage which you can trial render and compare with their Benchmark - - might be interesting.

Earlier Posts are beyond me, but may be just what you need.

Good luck.

**worddigger** · 06-09-2012, 05:42 AM

Originally Posted by vidmanners

VS user, but understood from Sony creative webinars that pro11 will use the graphics card for preview and renders . . . indeed the "demo" indicated it was nearly 3x the speed of Pro10.
+ Look at Vegas site FAQ's etc . . . yr Pc reads it's pretty fast.
Sony Tutorial has some test-footage which you can trial render and compare with their Benchmark - - might be interesting.

Earlier Posts are beyond me, but may be just what you need.

Good luck.

Thanks for the reference to the Sony Webinars. I've just glanced over them, so far, but the extracted FAQs concerning Vegas Pro 11 have some great information to go over. This is VERY helpful.

**worddigger** · 06-09-2012, 08:13 AM

Well, I tried the recommendations on these links:
Achieving smooth playback in the Video Preview window
Stuttering preview during playback
Still no joy. Looks like the only thing to do is use the "Shift + B" selective rendering option.

2] For anything more intensive that requires my scrutiny I'll do a SHIFT+B and have something like 200mb aside in the Prefs Settings for it. Going above 1000mb tends to bring VEGAS, on my 16gb PC to its knees.

At least I now know how to effectively use this option. And, since I have installed 8 gigs of RAM, I can selectively render a good sized chunk of the timeline by setting aside about 1000 mg in the Video Tab Prefs Setting. Again, my thanks to everyone who commented. I learned a few things I was unaware of.