flickering white frames appear when rendering

john-w9654 wrote on 9/1/2016, 8:35 PM

I have a program that is 57 minutes long. I am working in Sony Vegas Pro 13. I have Windows 7. I am trying to render the project in Internet HD 1080p mp4, with the frame rate at 23.976 (this matches my project settings). I render the project. When I look at the file I have created, the vast majority of it is fine. However, one or two shots will have mysterious flash frames of white flickering for a couple of seconds. I render the project again. This time the one or two shots that were affected before look just fine, but another shot at the very end suddenly has a few flash frames of white. I render again. This time that shot at the very end looks fine, but a zoom in near the middle of the program is affected by these flashes of white frames. So the problem will "bounce around" the timeline every time I render -- you never know when it will show up. But no matter how hard I try, I can never get the entire 57 minutes to render without one or two white flashing frames. Help, please!

Comments

OldSmoke wrote on 9/1/2016, 8:56 PM

Have you tried switching off GPU acceleration?

john-w9654 wrote on 9/1/2016, 9:25 PM

Yes, it is switched off. It has been switched off during this whole time. I was hoping to find it on when I saw similar posts suggest this, thinking this might be the answer. But it is off and I remember turning it off a while back. The problem still persists.

OldSmoke wrote on 9/1/2016, 9:30 PM

Where did you switch it off? Under preferences or in the render template?

NickHope wrote on 9/1/2016, 11:03 PM

This post shows the various places you can switch GPU acceleration on and off

john-w9654 wrote on 9/2/2016, 6:18 AM

Hey, Nick...ah...this is a revelation! Ha -- it was switched off under preferences and I did not check the render window. Sure enough, I have been rendering under MainConcept and checked the settings there, and I had "render using CPU only" under my encode mode. I have a NVidia graphics card and indications that CUDA is available, so I will try using the "CUDA if available" setting. It might be a while before I get back to you (busy day plus I have to check the entire hour-long program to check for those white flash frames) but overall I am very hopeful that this is the solution. Thanks and I will let you know what happens.

OldSmoke wrote on 9/2/2016, 7:32 AM

I had "render using CPU only" under my encode mode.

That is actually ok. What model of Nvidia card do you have in your system?

john-w9654 wrote on 9/2/2016, 7:39 AM

Graphics Card

1 x NVIDIA GeForce GTX 760 2GB

GTX760SYSTEM

john-w9654 wrote on 9/2/2016, 7:55 AM

I hope CUDA does the trick...at least it is an option I haven't tried and so maybe this will work.

john-w9654 wrote on 9/2/2016, 11:40 AM

Well, I still got a couple of flickering white frames. I am not too sure what else to do. Anyone else have this problem? This is a large project, I should say. It is 57 minutes long and every shot has been color corrected. Is it too big for Vegas to handle? Something else I am missing? I hate to think that all my work is for naught if I can't render this out properly. Most of it looks fantastic...it is just one or two frames of white that will flicker on...and with each render they appear in a different place. I am really at a loss. If anyone has a suggestion let me know.

OldSmoke wrote on 9/2/2016, 3:22 PM

Does the problem also appear at the beginning or shortly after it? I am thinking in the line of a system slowly overheating, especially CPU only rendering puts good and constant load in the CPU and it does require good cooling.

john-w9654 wrote on 9/2/2016, 3:40 PM

Well, I think I found the solution....I had been using Main Concept without any difficulty on previous projects, but with all these flash frames appearing at random in different places I thought I would have better luck with a Sony AVC render. So instead of Main Concept I decided to try Sony AVC Internet 1920 x 1080 30p. I changed the frame rate to 23.976 (as I did under the Main Concept dialog window) and under encode mode I chose "automatic (recommended)." I rendered and once again checked the entire program from beginning to end -- and it is a beautiful render. No problem, no frames of white, just a good, clean render. OldSmoke, thank you for your feedback and there might be some truth in your thoughts on the CPU only rendering...I think the temp is okay in my office but it really could be cooler...it is on the warm side. Thanks for your feedback, too, Nick. My own personal guess (which is just a guess) is the Sony AVC was able to handle a little bit better the various things that needed to be rendered, which included the use of a good number of Sony color correction tools. In any event, just changing to Sony AVC fixed the problem and I am pleased with the result. Thanks!😀