Issues rendering on GPU at 32-bit and over 1080p

AnandaT wrote on 4/15/2018, 10:54 AM

Hello again,

 

I've had this issue on previous version on Vegas (13 up to 15).

I render in 32-bit to avoid another issue I have with 8-bit (described at the end)

 

If I have the GPU enabled (in Preferences > Video) and try to render a 1920x1080 60p video, with 32-bit pixel format in the Project Preferences, it goes smoothly.

If I try to render into an uncommon or higher resolution (for example 2560x1080, or basically anything higher than 1920x1080), the render would start, and fail 10 seconds later with 'System is low on memory' error, like this:

My PC specs are as follows:

  • i7 4790K
  • 16GB RAM
  • GTX 970

I'm not sure which memory the error is referring to (RAM? VRAM?)

Checking the Windows Task Manager (Win 10), my GPU VRAM is barely at 2GB of 4GB when this happen, and RAM pretty far from being saturated (8GB of 16GB)

This is the Project Setting I use:


(Upping the resolution from that causes the issue)

Rendering as AVC/AAC MP4. Using other formats, like WMV do not have issue, but as far I know they don't use GPU acceleration.

 

 

If you wonder why I use 32-bit:

I'm using footage coming from Nvidia Shadowplay (game footage), and rendering in 8-bit gives a washed out preview (and much dark final render). I've been searching about this since I've been using 13, and there are many threads on this, but not many solutions (something about 0-256 and 16-256 levels). Using 32-bit is the only thing that gives me the same colors as the original footage.

Shadowplay footage format is as follows:

 

 

The issue is not present if rendering in 8-bit, but my final render colors are not the same as the original footage (did not matter on the player, as this would happen on any device/software/site I tried to play the video on)

So either a way to solve the thing with 32-bit rendering, or a way to get my colors not changed in 8-bit. I've tried other softwares like Premiere and Resolve and this color issue did not happen there.

 

If more information are needed, just ask. And sorry if post came out pretty confusing.

Cheers

Comments

Musicvid wrote on 4/15/2018, 11:13 AM

Welcome to the forums!

You didn't say if you have Vegas Pro, Movie Studio, or Movie Studio Platinum. It makes a difference.

8 bit is supposed to look flat in the Vegas Preview (16-235) in an 8 bit project so that it plays correctly in your player (0-255).. Instead of glossing over the information you found, you may want to read it thoroughly and begin the learning curve.

If you want to temporarily force the preview to display player levels, just add the Studio->Computer RGB Levels filter, making sure to remove it before rendering.

Placing 8 bit source in a 32 bit project is incorrect, always; the levels and gamma are not the same, and the processing times are unnecessarily horrendous.

Two articles we wish you would read:

https://www.vegascreativesoftware.info/us/forum/faq-why-does-my-video-have-more-contrast-than-the-vegas-preview--104567/

https://www.vegascreativesoftware.info/us/forum/faq-what-obs-studio-settings-work-well-with-vegas-pro--109925/

These, and answers for many more questions are to be found in the Vegas FAQ>

https://www.vegascreativesoftware.info/us/forum/vegas-pro-faqs-and-troubleshooting-guides--104787/

For further technical assistance, the information you need to consider providing is here:

https://www.vegascreativesoftware.info/us/forum/important-information-required-to-help-you--110457/

AnandaT wrote on 4/15/2018, 11:42 AM

Thank you, that information was really helpful!

I use Vegas Pro 15 (EDIT), and used Vegas Pro 13 previously.

And I'll take your advice about the 32-bit project & 8-bit source and avoid using that. Do you know if that would affect the generated media (I have some project with some fancy gradients, and I have yet to check if they would render the same in 8-bit).

 

I've attached screenshots of the original footage, preview and rendered result, so you can see the differences in the colors:

Original

Preview & Render at 8-bit

Preview & Render at 32-bit

 

Not much noticeable is the red-color on the gun, which shifts a bit (I guess that's inevitable). More evident is the 'flat' look in the 8-bit preview, which is not visible in the render.

 

Is there a reason why Vegas preview is 16-256 and if there's a setting for that? When editing (and particularly color correcting), it could be problematic as you don't get a 1:1 preview.

Musicvid wrote on 4/15/2018, 12:22 PM

Ananda, you ask good questions!

Is there a reason why Vegas preview is 16-256 and if there's a setting for that? When editing (and particularly color correcting), it could be problematic as you don't get a 1:1 preview.

Vegas displays the true levels that are in your video. It does not correct yuv video source to RGB playback levels during preview as some other editors do, sometimes incorrectly. I vastly prefer the way Vegas does it to Premiere, for instance. The levels filter I told you about is there to correct your Preview levels to Playback levels temporarily, before you render without the filter.

In your example above, the 8 bit preview and render appear to be correct! (I didn't scope them, but the relationship is exactly what we expect.)

Your 32 bit preview is close to correct playback levels, and the rendered gamma is incorrect. Note the degradation of shadow detail.

Generated media start life as RGB. You should put all generated media on their own dedicated track, and apply the Computer->Studio RGB Levels filter during the render. This is exactly the converse of what you did to preview your YUV source, and it is what you would do with any source having RGB levels.

The histogram scope can become your best friend, once you've played with it.

I know this seems like a lot of hoops to jump through, but it's a legacy of tube-tv days that we still have to honor, and unfortunately it will be with us for a very long time.

Here's a lighthearted look at the mess you "almost" got yourself into, and now that you've got a chance to learn from the ground up, best advice is "Don't Go there!"

https://www.vegascreativesoftware.info/us/forum/pc-to-tv-levels-a-comedy-of-errors--107325/

 

Marco. wrote on 4/15/2018, 1:13 PM

You could try if the "Preview Levels" option of "SeMW Extensions" would help you. I use it often to better control the internal preview.

Musicvid wrote on 4/15/2018, 3:30 PM

Yep, now that I have 14, I'm going to try it.

AnandaT wrote on 4/16/2018, 1:34 AM

Thank you all for the replies!

Thanks Marco. for suggestion that extension, will give it a try :)
EDIT: That extension is a god-send, really useful to see my render result with a click.