NDIStream

Free, open-source NDI sender & receiver for macOS.
Broadcast a camera, view any NDI source, record both sides with audio. One window each. No bloat.

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Download

Grab the latest universal .app from Releases. Unzip, drag into Applications, and launch. Signed and notarized, so no right-click-Open dance.

Why this exists

Every other Mac NDI tool is paid, locked inside NewTek's bloated NDI Tools suite, or both. NDIStream was built on a film set for a "fake Zoom" gag — lead actor's MacBook is the camera that ends up "in the call" via OBS, the off-camera scene partner sees the lead on a second Mac so she can act off her, NDI over a small GL.iNet travel router carries it. ~80–120ms glass-to-glass.

It's stayed small on purpose: one window for sending your camera, one window for receiving a source, and a record button on each. That's it.

Features

• Sender — broadcast any built-in or USB camera as an NDI source.
  • Quality preset (Native / 720p / 540p), frame rate (30 / 60), smooth-pacing toggle.
  • UYVY pixel format end-to-end, async send — minimal CPU on Intel Macs.
  • Optional microphone capture muxed into the NDI audio channel.
• Receiver — discover any NDI source on the LAN and view it in a resizable, letterboxed window.
  • Audio passthrough from the source.
  • Tally pill, reconnecting status, full-screen auto-hide chrome.
• Recording — independent H.264 .mov per window with audio.
  • Sender records video + mic; Receiver records video + NDI audio.
  • Files land in ~/Movies/NDIStream/ with timestamped slate filenames. One tap to start, one to stop, no save dialogs.
  • Auto-record mode and lock UI for unattended set use.
• Menu bar controls for headless streaming.
• Window menu — both windows are independently openable/closeable.

Requirements

• macOS 13 or later
• Apple Silicon or Intel (universal binary)
• NDI SDK for Apple installed at /Library/NDI SDK for Apple/ (only required to build — the released .app bundles libndi.dylib)
• XcodeGen (brew install xcodegen) — for project generation
• Xcode 15+

Build

xcodegen generate
xcodebuild -project NDIStream.xcodeproj -scheme NDIStream -configuration Release \
    -destination 'generic/platform=macOS' ARCHS="x86_64 arm64" ONLY_ACTIVE_ARCH=NO build

Or open NDIStream.xcodeproj in Xcode and hit Run.

The built .app is a universal binary (x86_64 + arm64), ~30 MB. libndi.dylib is bundled into Contents/Frameworks/ so the app runs on any Mac without the user installing the NDI SDK.

Use

Sender

1. Launch — Sender window opens by default.
2. Pick a camera, set NDI source name, toggle microphone if you want audio, hit Start Broadcasting.
3. Hit the red circle to start a recording; hit it again to stop. The folder icon opens ~/Movies/NDIStream/.

Receiver

1. Window menu → NDIStream — Receiver to open it.
2. Pick a discovered source from the dropdown, hit Connect.
3. Record button works the same way — records video and NDI audio.

Notes

• Not sandboxed (NDI uses mDNS / UDP multicast and needs raw network access).
• Hardened runtime + library validation disabled so the bundled libndi.dylib loads.
• Microphone permission is requested on first broadcast with audio enabled.

Looking for…

• A free NewTek NDI Tools alternative for Mac? This is it — Sender and Receiver in one ~30 MB app.
• An NDI source for OBS, vMix, Resolume, TouchDesigner? Run NDIStream's Sender, pick it up as an NDI source in your app.
• A way to monitor an NDI feed on a second Mac? That's the Receiver — discover and view any source on the network.

License

MIT.