win-capture-audio

Capture the audio of individual Windows applications in OBS Studio — by executable name, mixed into one source, with exclude and hotkey modes. No virtual audio cables, no per-window fiddling.

This is a modernized fork of bozbez/win-capture-audio (unmaintained since 2022), updated to build and run against OBS Studio 28–32 on current Windows 10/11, with a substantial number of threading, COM-lifetime and audio-timing fixes. See the CHANGELOG for everything that changed.

Features

• 🎯 Capture by executable name. Pick applications by their .exe, not by a window, so capture keeps working when the application restarts. Names are case-insensitive and accept wildcards (League*.exe).
• 🎛️ Several applications in one source. Their audio is mixed and timestamp-aligned into a single OBS source.
• 🚫 Exclude mode. Capture everything except the listed applications — the usual way to keep music off a recording track while it still plays on stream. Works whether or not the excluded application is running.
• ⌨️ Hotkey mode. Capture whichever application is in the foreground when you press a hotkey, and release it with another.
• ⏱️ Latency setting. Lower the mixer's alignment window when capturing a single application; keep the safer margin when mixing several.
• 📊 Live status and refresh. The properties dialog shows what is actually being captured (Capturing: chrome.exe), and the active-session list can be refreshed without reopening it.
• 🔁 Automatic re-attach. Capture recovers on its own when an application restarts or the audio device changes.
• 🌍 15 languages.

Compared to OBS's built-in "Application Audio Capture (BETA)"

	win-capture-audio	OBS built-in
Select application by	executable name, wildcards	window
Survives application restart	✅	❌ stops when the window closes
Applications per source	as many as you like, mixed and aligned	exactly one
Exclude mode	✅	❌
Hotkey mode	✅	❌

Internally both use ActivateAudioInterfaceAsync with AUDIOCLIENT_PROCESS_LOOPBACK_PARAMS.

Note: the exclude mode replaces OBS's "Desktop Audio" source rather than filtering it — no plugin can remove an application from Desktop Audio, since that source captures the mixed output of the sound device. Add an exclude-mode source and disable Desktop Audio in Settings → Audio.

Requirements

• OBS Studio 28 or later (tested against 32.2.x)
• Windows 10 2004 or later / Windows 11

Installation

Grab the latest release:

• Setup installer (recommended): removes any older version automatically, including 2.2.x installs inside the OBS directory.
• Portable zip: extract into %ProgramData%\obs-studio\plugins\.

The resulting layout is OBS's modern per-plugin layout:

C:\ProgramData\obs-studio\plugins\win-capture-audio\
├── bin\64bit\win-capture-audio.dll
└── data\locale\*.ini

Restart OBS and add the "Application Audio Output Capture" source.

The old layout inside the OBS installation directory (obs-studio\obs-plugins\64bit\ + obs-studio\data\obs-plugins\win-capture-audio\) also still works.

Usage

Capture specific applications — leave the mode on "Capture audio sessions from a selection of executables" and add entries to the executable list, either by typing them (wildcards allowed) or by picking a running application from the active sessions dropdown and clicking Add.

Capture everything except some applications — same mode, tick "Capture all audio EXCEPT sessions from the selected executables". Remember to disable Desktop Audio (see the note above), or you will hear everything twice.

Hotkey mode — switch the mode to "Capture foreground window with hotkey", then assign the two hotkeys in Settings → Hotkeys under this source: "Capture foreground window" and "Deactivate capture". (Those are the plugin's hotkeys — not the standard Show/Hide entries listed above them, which only toggle the source's visibility.) Focus the application you want and press the capture hotkey.

Apps that play audio from more than one process

Some applications route part of their audio through a separate process with a different executable name, so one list entry does not cover everything:

Application	What's missing	What to add
Valorant / League of Legends	voice chat plays from Riot's client, not the game	Riot*.exe (or use hotkey mode on the game)
Microsoft Teams (new)	runs as its own process, not Teams.exe	ms-teams.exe
Games behind launchers	launcher sounds vs. game audio are separate trees	one entry per executable

The universal trick: while the missing audio is actually playing, open the source's properties and check the active sessions dropdown — whatever process is producing that audio appears there under its real name; add it. The status line also lists entries that match no running session, which is usually a typo.

Building

Requirements: Visual Studio 2022 or later (MSVC C++ workload) and an installed copy of OBS Studio.

git submodule update --init
cmake -S . -B build -A x64
cmake --build build --config RelWithDebInfo

There is no libobs SDK on Windows — OBS's installer ships no headers or import libraries. The build instead runs cmake/bootstrap-obs-sdk.ps1 automatically, which:

1. detects your installed OBS Studio and its exact version,
2. downloads the matching obs-studio tag's libobs headers, and
3. generates obs.lib directly from your installed obs.dll's export table,

so the plugin is always built against exactly the OBS binary it will load into. To install into %ProgramData% after building:

cmake --install build --config RelWithDebInfo

If you have a self-built OBS instead, point CMAKE_PREFIX_PATH at it and the usual find_package(libobs) path is used.

Release binaries are built by CI against the OBS 28.0.0 headers on purpose: libobs is forward-compatible, and declaring the oldest supported API lets one binary load on every OBS release from 28 through 32.

Troubleshooting

• "Windows protected your PC" when running the installer — the binaries are not code-signed yet, so SmartScreen has no reputation for them. Choose "More info" → "Run anyway", and verify the download against the SHA256SUMS.txt published with each release if you want to be sure it was not tampered with.
• Source not showing up — check the OBS log (Help → Log Files) for a [win-capture-audio] line. If absent, the DLL is in the wrong directory — see the layout above.
• No audio captured — make sure the target application is actually playing audio and appears in the Windows volume mixer. The capture attaches per audio session; an app that has not opened an audio stream yet has nothing to capture.
• Hotkey does nothing — make sure you bound the plugin's own hotkeys ("Capture foreground window" / "Deactivate capture") for the source, not the generic Show/Hide ones.
• Crackling or dropouts — lower the OBS audio buffering (Settings → Advanced → Audio) or report it with a log.

Found a bug? Open an issue and attach your OBS log.

Credits & license

Originally written by bozbez; maintained in this fork by Ayrton09.

GPLv2 — see LICENSE.