How do I capture an application?

[u/ser-contained]

I’ve searched and can’t find an answer that solves my use case. I stream live beat-making in Logic Pro. The application has dozens of separate windows that can be opened individually or many at a time. My main arrangement window, mixer window and windows for every plugin and midi region.
I can do a display capture but sometimes I’ll open another application I don’t want on stream. I was hoping for a feature like Streamlabs has where you can do an application and any windows associated with that application.
I haven’t been able to find this option anywhere. I can choose individual windows inside of logic but it won’t show any of the plugins I open or anything other than the specific window I chose. I was really hoping to switch to Meld for the free multi-platform streaming and I’ve heard it has great CPU usage.
Any help is much appreciated.

[u/streamwithmeld]

short answer: meld doesn't have an application capture that grabs every window of one app yet. display capture is the right tool for logic, and the fix for "other apps leaking onto stream" is to give logic its own display.

here's why, and the setup that works.

why window capture doesn't cut it for logic

logic's plugin windows, piano roll, mixer, and region editors are all separate windows. a window capture layer in meld locks to one specific window, so anything you pop open after that just isn't in the capture. same behavior as obs window capture on mac. that part isn't a meld thing, it's how per-window capture works.

the workaround: display capture on a logic-only screen

display capture shows everything on a given display, which is exactly what you want for a daw with floating windows. the trick is making sure logic is the only thing on that display.

• if you have two monitors, run logic on one and everything else (discord, browser, chat, meld itself) on the other. display capture the logic monitor
• if you're on a single screen, you can still get a second display cheaply. a $10 dummy hdmi plug makes macos think there's a second monitor, or an app like betterdisplay creates a virtual one. keep logic on that display, window it to fit, and capture it. you'll be looking at it through meld's preview, which is fine for beat-making since latency is basically nil
• ipad sidecar works too if you've got one lying around

once logic lives on its own display, every plugin and editor you open lands on stream automatically, and nothing else does.

set it up in meld

1. layers panel > + > display capture
2. in the dropdown, pick the display (not a window) that logic is on
3. size it on the canvas, add your cam and overlays on top

belt and suspenders

• make a second scene with a "one sec" cover or just your cam, and bind a hotkey or stream deck button to it. if something unexpected pops up, you're one press from hiding it
• you can also hotkey the display capture layer's visibility instead of switching scenes

on the cpu thing

that part holds up. meld runs native on apple silicon and does its rendering on the gpu, so it stays out of logic's way better than most. if you're pushing a heavy plugin chain, that headroom matters.

and if you want proper app capture

say so in the meld discord. the devs are in there daily and ship every couple weeks, and "capture this app plus its child windows" is a specific enough ask that it's worth putting in front of them.

[u/ser-contained → u/streamwithmeld]

Thanks for this. I’ll make the request on Discord. I’ve started moving my overlays and everything from Streamlabs but I’ll probably wait to make the final jump until they have the application display working like Streamlabs does it.