Mixed-source scene: display capture is sluggish but other concurrent sources are fine and I'm not dropping frames (video linked)

reinfeldx

New Member
This only occurs when display capture is capturing a full-screen game; if I run a game in borderless window mode, display capture works fine. My webcam is capturing smoothly and OBS stats say I'm not dropping frames.

Video example here. Notice my webcam is unaffected: https://youtu.be/inTzgkvsTCY

Any idea why this would be? I've used OBS quite a bit in the past and I don't recall ever running into this issue. Game mode works fine, but display capture would work better for my purposes.

Canvas & Output: 1080p 60fps | x264 | CBR | 5000 Kbps | Profile: main
i7-4770 | 1050 Ti | 24 GB Ram
 

Attachments

FerretBomb

Active Member
Monitor Capture is the least-performant capture method, and can cause significant intermittent performance issues if it is included in a scene with a Game or Window Capture (even if they are not concurrently visible). These can come and go without rhyme or reason... working fine for months or years, only to crop up for a few days, then disappear again.

It should be avoided at all costs, only used as an absolute last resort; if it has to be used, it should be in a separate scene, on its own.
 

reinfeldx

New Member
Thanks for the reply. What’s strange is that monitor capture works fine as long as a game isn’t running in full-screen mode. Do you know why that would be?
 

FerretBomb

Active Member
When running (true) fullscreen in-game, the game itself takes over handling the screen draw/rendering from the Windows Desktop Compositor process that normally handles it when running in Windowed/Borderless mode. This is why some games will perform better in fullscreen... they don't have to funnel everything through the compositor layer. (Also why alt-tabbing out forces the game to minimize, as the WDC takes over rendering the screen again.)
Unfortunately, this forces the Display Capture to use an even lower-performing fallback capture method, instead of just grabbing the composited texture from the WDC memory space.
 
Top