OBS Studio's compositing model is scenes stacked with sources

The setup

OBS Studio is the free, open-source broadcast application that sits underneath most VTuber setups, whether the avatar comes from Live2D, a VRM model, or a game engine capture. The OBS Project maintains its own knowledge base rather than relying on third-party wikis, and as retrieved on 16 September 2026 that knowledge base states the software's core model plainly in the Sources Guide: 'Scenes and Sources are the meat of OBS Studio.' A scene is a saved layout; a source is anything placed inside it, from a webcam feed to a captured application window. This is the publisher's own description, not independent commentary.

What the documents show

The Quick Start Guide lists the capture types a new user meets first: Display Capture and Window Capture for a whole screen or single window, Game Capture for hardware-accelerated 3D games on Windows, and Video Capture for a webcam or capture card. A second document, the Window Capture Sources page, adds detail the quick-start guide does not: capture methods differ by operating system, and OBS documents separate Xcomposite and PipeWire variants of Window Capture on Linux with different availability. That distinction matters for a VTuber running a Live2D or VRM viewer as a separate application window rather than a game, because the correct capture method depends on the platform, not on the avatar software.

The craft

In practice, a VTuber's scene is a stack: a background or overlay image at the bottom, the avatar capture window in the middle, and alert or chat widgets from a service on top, ordered in the Sources list where items higher in the list draw over items below. The Sources Guide documents that ordering explicitly, along with cropping a source via the Edit Transform window so only part of a captured window shows. None of this is unique to VTubing; OBS documents it as general compositing behaviour, and the craft is choosing which general tool serves an avatar-specific need, such as isolating a transparent capture window from the rest of a desktop.

Keeping the creator in control

Because OBS is free, open-source, and runs entirely on a creator's own machine, the compositing decisions belong to the performer, not to a platform or a paid service. Nothing in the documents reviewed here describes OBS collecting or transmitting a creator's capture content; the software's job, as documented, ends at producing an output feed. This is an editorial observation, not a claim the documents make directly: local compositing keeps character design and framing decisions in the creator's hands until the moment they choose to stream or record.

• Which capture type does the avatar viewer actually need on this operating system?
• Is the Sources list ordered so nothing unintentionally hides the avatar or an alert widget?
• Does the current OBS knowledge base page still describe the same capture options, given it is a living document?

Reading OBS's own documentation instead of a fan tutorial separates what the software guarantees from what a particular setup video happened to show. Scenes and sources are the whole model; everything else is composition built on top of it.