[macOS Ventura] new Application/Display capture drops frames, particularly in fullscreen, particularly for low FPS sources

Operating System Info

Other

Other OS

macOS 13

OBS Studio Version

28.0.0

OBS Studio Version (Other)

28.0.0

OBS Studio Log URL

https://obsproject.com/logs/sdjIGgIfvysdkC6U

OBS Studio Crash Log URL

No response

Expected Behavior

macOS Screen Capture Application/Display capture not to drop frames.

Current Behavior

macOS Screen Capture Application/Display captures drop frames. The problem seems to be exacerbated greatly in fullscreen, and the problem also seems to be exacerbated when the source is rendering at a low frame rate.

Steps to Reproduce

I am currently reliably reproducing this on the current Ventura developer beta (22A5331f) on an M1 Max MacBook Pro, with no external monitors plugged in.

1. Under macOS Screen Capture, add a Display or Application capture source (see below for list of apps for which it is occurring/not occurring). Issue will be more noticeable if the source is rendering at a low frame rate.
2. Set that source application or window to fullscreen.
3. Observe many dropped frames in preview/output.

Anything else we should know?

The issue does NOT seem to be exclusive to fullscreen, but it is much more noticeable when the application is in fullscreen.

Dropped frames seem to decrease when UI and cursor movement is being rendered, and increase when it's only the source being rendered.

I have reproduced this capturing the following applications in either the Display or Application capture modes:

VLC (with low frame rate video)
Parallels
Dolphin

It seems to NOT be reproducible, or at least easily noticeable, in the following:

QuickTime
Safari
Other system applications

Attached are several videos showing the issue, with either Application or Display capture on the left, and simultaneous Window Capture (macOS Screen Capture version) on the right.

The final video shows a 60fps source, where the problem is lessened but still seems to be present.

https://user-images.githubusercontent.com/6864788/188241363-d73532c7-0e6a-492d-aadc-242a6cff5b81.mov

https://user-images.githubusercontent.com/6864788/188241389-43e08ec6-96df-4079-ab43-4c6664ab0d36.mp4

https://user-images.githubusercontent.com/6864788/188241413-cf6ef7e4-3ee0-4b8a-9dee-b7812bc283fd.mp4

https://user-images.githubusercontent.com/6864788/188241426-75785e8c-86d4-47b0-a813-5e3630eb4321.mp4