Open-source media playback and show control for live video. Load your media. Build your playlist. Take it live.
deckboy website — what it does, and where to download it. · How it compares to Mitti, PlaybackPro, QLab, Millumin and vMix — including where they win. · Manual — all of it, twenty-six chapters. · FAQ · Where latency hides — the four stages of a live chain, in frames and milliseconds
Shown with the test patterns Deckboy generates itself, so nothing here is anyone’s show file.
Every release ships an installer and a portable build for each platform. Both bundle everything they need — binary, ffmpeg, runtime libraries. Nothing else to install.
| Platform | Installer | Portable |
|---|---|---|
| Windows | …-windows-x64-setup.exe — Start Menu, uninstaller, .deckboy file association |
…-windows-x64.zip |
| macOS (Apple Silicon) | …-macos-arm64.dmg — drag to Applications |
…-macos-arm64.zip |
| macOS (Intel) | …-macos-x86_64.dmg |
…-macos-x86_64.zip |
| Linux | …-x86_64.AppImage — one file, chmod +x and run |
…-linux-x86_64.tar.gz |
Both control surfaces ship with every release, so neither needs a build:
Stream Deck (…streamDeckPlugin — double-click it) and Bitfocus
Companion (Deckboy-companion-module-….zip — unzip it, then point
Companion's developer modules path at the folder containing it;
INSTALL.txt inside has the three steps).
"Unknown developer" warnings — what to do
Deckboy is not code-signed. Signing is a paid developer account with Apple and with Microsoft, and the project has not bought one -- so the builds are fine and the OS simply does not recognise the publisher. It is on the roadmap below for the macOS releases, where the warning is most in the way.
-
macOS — if it says the app is damaged, clear the quarantine flag once:
xattr -dr com.apple.quarantine /Applications/Deckboy.appInstall from the
.dmginto Applications rather than running from Downloads; that is also what avoids Gatekeeper's App Translocation sandbox. -
Windows — SmartScreen may say "Windows protected your PC". Click More info → Run anyway.
-
Linux — the AppImage runs on any current distribution. Graphics, display server, audio and the C/C++ runtime deliberately come from the host: they have to match the machine actually running, and a bundled libGL cannot load your GPU driver. Built on Ubuntu 24.04 / Mint 22, so target that vintage or newer.
Deckboy is a native desktop application for video engineers, AV technicians and live operators who need a reliable way to organise media, trigger cues, loop content and send video to production displays.
That is the job it is built around, and it is built on a stubborn principle: Seize the means of playback ♡
No subscription ♡ No account ♡ No telemetry ♡ Nothing phones home. And no licence server that can refuse to start the show at 19:55 because it could not reach the internet. The machine you carried into the venue is the machine that plays the show.
- 🎯 Prepare media cues ahead of time
- 🚀 Trigger clips instantly during a show
- 🔁 Keep loops running reliably
- 📺 Send video to dedicated fullscreen outputs
- 🎛️ Control playback remotely from production tools
The same box speaks NDI, SDI, SMPTE ST 2110, SRT, RTMP, Spout, LTC timecode, OSC, Art-Net and NMOS — so the machine you brought for playout usually solves the other five problems on the day as well.
- Convert media that will not play well, in place, without leaving the app
- Inspect any file — codec, raster, frame rate, channels, duration — by importing it
- Generate test patterns and a test card to prove a chain end to end
- Capture a camera, a window or a screen and treat it as a cue
- Bridge formats — NDI in, SDI / ST 2110 / SRT / RTMP out, simultaneously
- Normalize loudness to EBU R128 when a client sends a clip mastered too quiet
- Generate LTC timecode on its own routable output
Live events • Corporate presentations • Churches • Schools & universities • Museums & installations • Digital signage • Projection • LED walls • Streaming
And the jobs in between: bench-testing a screen before anyone arrives, proving a cable or converter with a real test card, getting an NDI source onto SDI, restreaming to SRT and RTMP at once, or making a client's unplayable file playable on site, minutes before doors.
Playback & cues
- Cue-based video playback with playlist management
- Drag-and-drop media import
- Play, pause, stop, seek and clear
- Looping and hold-last-frame behaviour
- Fade in/out, per cue and per deck
- Cue trimming, and per-cue transition overrides
- Thirteen transitions: cut, crossfade, dip to black or white, four pushes, four wipes and an iris — set per deck, overridden per cue, timed in seconds
Video output
- Dedicated fullscreen output windows, multiple displays, display selection
- Display-native and fixed raster modes
- Area of interest, edge feathering, warp / keystone correction
- Per-output matte and still overlay, composited into the output's own picture
- NDI output
- DeckLink (SDI) output, wherever the Blackmagic SDK is present
- SRT and RTMP streaming, configurable independently and live at once
Live sources
- Stream cues take
srt://,rtmp://,rtsp://,udp://and http HLS - NDI receive, and Blackmagic DeckLink capture through the SDK rather than a pipe
- Camera, desktop window and screen capture
- IPTV channel lists: import an
.m3uand every channel becomes a cue, named from the entry with its group in the notes. An HLS media playlist that happens to share the extension is spotted by its#EXT-X-tags and played as one stream instead of imported as one cue per segment
Presenting from slides
- Import a PDF, PowerPoint or Keynote deck as one cue per slide, rendered once at import by the platform's own engine -- nothing during the show depends on a document renderer
- Speaker notes come with the deck: read out of a
.pptxdirectly, or from a.pdfpc/.notes.txtsidecar beside a PDF. A team working a master deck in Google Slides can export both and keep its fonts and its notes - Presenter view as an output type, so it takes its own display: the live slide, the one before it, the one after it, the notes and the clock. Every panel switches off on its own, the colours are yours, and the panels are dragged into place rather than chosen from a list of layouts
- Notes split into parts on a line of
---and the clicker walks them, scrolling a long note at the speaker's pace instead of showing it all at once. Or split one cue into one cue per part, if you would rather they were in the playlist - Page Down and Page Up are a presenter remote, because that is what every clicker sends
- Teleprompter view, also an output type, for the person in front of the camera: the script very large, scrolling up through a fixed reading line at a pace set in lines per minute, and mirrored for a beamsplitter. It prompts from the live cue's notes, or from a script of its own. Run, stop, jog, pace, size and mirror are all on the control protocol, which is what a hand controller drives
Broadcast / IP video
- SMPTE ST 2110-20 uncompressed video output
- SMPTE ST 2110-30 (AES67) audio output
- PTP (IEEE 1588 / SMPTE ST 2059) media clock slaving
- AMWA NMOS IS-04 registration and Node API
- AMWA NMOS IS-05 connection management, so a broadcast controller can discover and route Deckboy's senders
ST 2110 output is marked experimental in the interface, and honestly so: it is a conformant packetiser, but it is not narrow-model paced (that needs hardware pacing), and NMOS discovery is by configured registry URL rather than mDNS. See docs/ST2110_FEASIBILITY.md.
Audio
- Per-cue gain trim, pan and mono fold-down
- EBU R128 loudness normalization
- Independent audio fades, separate from video fades
- Content-authoritative stereo waveform display
- Audio-only cues, and per-cue mute
- A per-cue effect chain -- high pass, low pass, tilt EQ, compressor, gate, delay, reverb, width and binaural placement, in the order you put them in
- Five effects that use what the deck knows, which is something no plugin is ever told: the cue's own picture driving a filter, its position on the output becoming the sound's position in the room, the approaching end of the cue resolving the tail, stutter quantised to the video frame period, and a held cue keeping its room tone instead of stopping dead
Show control
- Bitfocus Companion integration (module included)
- OSC input and OSC Query
- TCP command control — every verb answers
OKorERR - HyperDeck protocol emulation, so a deck controller can drive it
- Tally-driven playback: roll when an ATEM or an NDI receiver puts you on air
- LTC timecode in, and an LTC generator routable to its own device and channel
- MIDI input, Art-Net / DMX, NMC transport sync in and out
Sources
- Video clips, images and audio files
- Slide decks — a PDF imports as one image cue per page, rendered at import by the platform's own engine, so nothing during a show depends on a document renderer
- Browser sources, on all three platforms
- Camera, window and screen capture, on all three platforms
- SRT, RTMP, RTSP and UDP stream input; NDI source input
- Test patterns and a built-in test card
- A code source — a live-coded expression evaluated per pixel, edited while it runs, with a compile error that never blacks the output
Effects & mixing
- A per-cue effect stack on every kind of cue, ordered, with copy/paste of a whole chain between cues
- Thirty-six effects, each with named parameters, all measured to fit inside a
60fps frame at 1080p —
--effect-benchprints what each one costs - Six that exist nowhere else: schlieren gradient imaging, Chladni nodal figures, a true wave equation with inertia, crystal grain growth, retinal rod/cone persistence, and structure tensor grain flow
- An LFO on any parameter — six shapes, free running or locked to a tap tempo
- VJ mode: a second deck live, a crossfader with ten blend modes — dissolve, add, screen, multiply, lighten, darken, subtract, undercut, infiltrate and ember — tap tempo, and takes quantised to the beat
Interface
- Themeable, including high-contrast terminal themes suited to OLED panels
- Timeline with filmstrip thumbnails; resizable program monitor and timeline
- UI scale that follows the desktop's own scaling
- The interface reads in 38 languages, including Cubano, Klingon and a few written in cypher
- Missing-media detection with folder relink, so a moved drive does not cost you a rebuild
Deckboy collects nothing and sends nothing to its developers. No telemetry, no usage reporting, no crash upload, no account. Crash logs are written to a file next to the app for you to read or forward, and they stay there.
There is an update check, and it is off by default. Switched on, it asks GitHub's releases API whether a newer version exists — nothing about you goes with the question, and finding one never installs anything without you saying so. A machine sitting on a venue's network should do nothing nobody asked it to.
It is deliberately network-active — NDI discovery, PTP, NMOS registration, OSC, Companion control and streaming all talk to the network by design. Every one of those goes to your own LAN or to a destination you configured.
App texture sharing. Spout output works on Windows — Deckboy's picture appears as a Spout sender that Resolume, TouchDesigner or OBS can pick up. Spout input (treating another app's texture as a cue) is not built yet, and Syphon on macOS is not built at all. Deckboy reports the missing halves as unavailable rather than accepting frames and quietly discarding them.
Hardware decode. Two separate things. The decode runs on hardware where the platform has a decoder: D3D11VA on Windows, VideoToolbox on macOS, VAAPI on Linux. The frame additionally avoids a copy on Windows and macOS -- on Windows the decoder can be put on the output renderer's own device, and on macOS a VideoToolbox frame is an IOSurface that a Metal texture can wrap directly, so either way the picture never touches system memory.
On an Apple M4, ten seconds of 4K30 costs about half a second of CPU that way against five and a half in software.
Neither is about making playback possible — software decode is comfortable on
modern hardware for ordinary material — they are about what else the machine can
do at the same time. --decode-bench reports which decoder ran, and
DECKBOY_NO_HW_DECODE=1 forces software so the two can be compared on your own
machine with your own footage, which is the only comparison worth anything: the
saving depends on the codec and on how old the GPU is, and on a sufficiently old
one the hardware decoder can be the slower of the two.
Everything else in the list above runs on all three platforms.
- Code map — file inventory, data flow, threading model
- Packaging guide
- Changelog
- ST 2110 feasibility
The changelog is the authoritative record of what landed and, just as importantly, what each feature deliberately does not do.
- Layer-based compositing and picture-in-picture layouts
- NMOS discovery over mDNS, so a registry no longer has to be configured by URL
- Hardware-paced ST 2110 output for narrow-model compliance
- Syphon output on macOS, and Spout/Syphon input as a cue source
- Developer ID signing and notarization for macOS releases
Deckboy is free software under the GNU General Public License v3.0 or later. Copyright © 2026 Deckboy Contributors. The full text is in LICENSE.
Bundled components keep their own licences — ffmpeg ships with its LGPL/GPL notice beside the binary, and the NDI and DeckLink SDKs are loaded at runtime rather than distributed.
Deckboy is built in the open and contributions are welcome — code, bug reports, documentation, testing, or production feedback from a real show.
The best open-source tools are built by the communities that use them.
Actively developed, and Windows-first. The core playback workflow is complete: cue playlists, fullscreen outputs, remote control and live production integrations.
macOS and Linux build from the same source and are checked by CI on every commit, in both full and reduced-feature configurations. macOS has a portable, self-contained app bundle; Linux ships a portable tarball and an AppImage.