Topic: SVP massive stutter with full-SBS files 3840x1080

When playing full-OU, half-OU or half SBS, SVP works but not when playing full-SBS files of 3840x1080. I get large stutters even when downscaling to 1080p which makes it unwatchable.

2 Reply by dawkinscm (edited by dawkinscm 16-05-2025 10:00:10)

Re: SVP massive stutter with full-SBS files 3840x1080

This looks like it is an issue the mpv dither algorithm I was using. Full SBS resolution causes processing issues but full OU resolution doesn't. Strange!

Re: SVP massive stutter with full-SBS files 3840x1080

try to turn off "3d" mode in SVP

4 Reply by dawkinscm (edited by dawkinscm 16-05-2025 13:13:15)

Re: SVP massive stutter with full-SBS files 3840x1080

Chainik wrote:

try to turn off "3d" mode in SVP

Thank you for the suggestion I will try that. There's something I don't understand. I assumed SVP was only processing half of the 3D image so if this does help then why?

Edit:
BTW it does help a little with the problem. But if you don't mind I would like to understand why I should turn off 3D mode for 3D movies.

Thanks again.

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Re: SVP massive stutter with full-SBS files 3840x1080

"3d mode" in SVP cuts the frame into two halves then processes them independently, then merges them back into large frame
splitting and merging large frames are not really fast operations in Avisynth/Vapoursynth...

not a problem with 1920*2160, but a big performance penalty for 4K+ stereo clips

6 Reply by dawkinscm (edited by dawkinscm 17-05-2025 05:50:35)

Re: SVP massive stutter with full-SBS files 3840x1080

Yep that makes sense thanks. After years of using full-OU I wasn't expecting full-SBS to be even more resource intensive.

So I've started using hwdec which I didn't need with full-OU, a weaker dither algorithm and desktop resolution is set to HD.

Thanks again.

7 Reply by dawkinscm (edited by dawkinscm 23-05-2025 15:42:14)

Re: SVP massive stutter with full-SBS files 3840x1080

Chainik wrote:

"3d mode" in SVP cuts the frame into two halves then processes them independently, then merges them back into large frame
splitting and merging large frames are not really fast operations in Avisynth/Vapoursynth...

not a problem with 1920*2160, but a big performance penalty for 4K+ stereo clips

Everything is working now that I've change a few things, but it's been a while since I've seen my GPU maxing out at 100% even though SBS is down-scaled to HD.  But setting SVP to 2D mode does help more than I realized and brings the GPU down to less than 50% and there doesn't seem to be any reduction in quality but more testing is needed. BTW, is there a way I can make 2D mode always the default? I unticked select 3D by aspect ratio but SVP is still detecting 3D and setting SBS.