workflow-live-production

Workflow — Live Production

What: Run a live show end-to-end. OBS is the mixer; MIDI controllers trigger scenes; DMX lighting and PTZ cameras follow scene changes; system audio is correctly routed; MediaMTX fans the output to HLS + RTSP + SRT + WebRTC + RTMP.

Who: Streamers, broadcasters, church/corporate AV, venue operators, esports shoutcasters.

Skills used

Role	Skill
Scene authoring	obs-config
Remote control	obs-websocket (auto-discovers URL+password from local OBS)
In-OBS scripting	obs-scripting
Native plugin authoring	obs-plugins
Doc lookup guardrail	obs-docs
MIDI surface	media-midi
OSC surface	media-osc
Stage lighting	media-dmx (via OLA daemon)
PTZ cameras	ptz-visca, ptz-onvif
System audio	audio-coreaudio / audio-wasapi / audio-pipewire / audio-jack
Multi-protocol egress	mediamtx-server
WebRTC contribution	ffmpeg-whip
Capture	ffmpeg-capture
Hardware encode	ffmpeg-hwaccel
NDI ingest	ndi-tools
SDI ingest	decklink-tools

Pipeline

Step 1 — Build the scene collection

Author the scene tree as JSON under the active OBS profile via the obs-config skill. Lock scene names early — downstream skills reference them by exact spelling (case-sensitive in the websocket protocol).

Step 2 — Route system audio BEFORE launching OBS

OBS caches audio devices at startup. Create virtual sinks first so OBS sees them as inputs.

• macOS: create an aggregate device combining BlackHole + mic (audio-coreaudio skill).
• Linux (PipeWire): create a sink and link source apps into it (audio-pipewire skill).
• Windows: install VB-Cable / VoiceMeeter, enumerate devices (audio-wasapi skill).

Step 3 — Start OBS and verify obs-websocket

OBS 28+ bundles obs-websocket v5. Use the obs-websocket skill's wsctl.py check + ping — it auto-discovers the password from the local OBS config. For remote OBS, export OBS_WEBSOCKET_URL and OBS_WEBSOCKET_PASSWORD.

Step 4 — Wire MIDI / OSC triggers to scene switches

Use media-midi (midictl.py monitor --json) piped to obs-websocket (wsctl.py scene-switch). For TouchOSC / Reaper, use media-osc (oscctl.py listen --port 8000 --json) with the same fan-out pattern.

Step 5 — Lighting cue on scene change (DMX)

Subscribe to OBS's CurrentProgramSceneChanged event via wsctl.py events --subscribe scenes, then drive DMX through media-dmx (dmxctl.py send/fade --universe N --channel M).

Step 6 — PTZ preset recall on scene change

Same subscription stream. For VISCA cameras (UDP port 52381), use ptz-visca (viscactl.py preset-recall --host <ip> --preset N). For ONVIF, use ptz-onvif after discovery (onvifctl.py discover).

Step 7 — Multi-protocol egress via MediaMTX

Configure the mediamtx-server skill once: RTMP ingest from OBS, auto-republish to HLS (8888), RTSP (8554), SRT (8890), WebRTC/WHEP (8889). Optional runOnReady spawns an ffmpeg forwarder to YouTube/Twitch/Facebook.

Step 8 — WebRTC low-latency path (alternative to RTMP)

Skip OBS's RTMP output and go straight to WHIP via ffmpeg-whip — sub-second latency for contribution.

Variants

• Pure-software — skip DMX/PTZ/DeckLink; software MIDI (Keyboard Maestro) + virtual audio + OBS only.
• Broadcast SDI — swap screen capture for DeckLink input via decklink-tools; playout back to SDI with ffmpeg's -f decklink output.
• NDI-first facility — replace RTMP ingest with NDI via obs-ndi plugin; MediaMTX still bridges to external delivery.
• Remote producer + FOH operator — both run OBS; operator drives producer's OBS over obs-websocket by setting OBS_WEBSOCKET_URL to the producer's LAN address.

Gotchas

• obs-websocket auto-discovery is local-only. For a remote OBS, export OBS_WEBSOCKET_URL + OBS_WEBSOCKET_PASSWORD.
• obs-websocket v5 only. v4 is EOL. Close code 4010 = client/server version mismatch.
• OBS caches audio devices at launch. Create virtual sinks before starting OBS.
• HighVolume events (bits 16–19) are deliberately excluded from All (=4095). InputVolumeMeters fires every 50 ms. Only subscribe if you're rendering a meter UI.
• PTZ presets are camera-stored. preset-set once, preset-recall forever.
• VISCA-over-IP is UDP:52381. No handshake. Firewalls between camera and controller silently drop.
• ONVIF WS-Discovery is multicast on 239.255.255.250:3702. Does NOT cross VLAN boundaries without an IGMP-aware switch.
• DMX via OLA requires olad running. Art-Net controllers often want a dedicated 2.0.0.0/8 subnet per spec.
• Art-Net universe is 0-indexed; DMX channel is 1-indexed. --universe 0 --channel 1 = first channel of universe 0.
• MediaMTX ports: 8888 (HLS), 8889 (WebRTC), 8554 (RTSP), 8890 (SRT), 1935 (RTMP), 9997 (API). Overlap with another service = silent boot failure.
• MediaMTX runOnReady inherits stdin from the daemon. Always pass -nostdin to ffmpeg inside those commands or the encoder blocks.
• NDI runtime (NewTek/Vizrt) is a separate install from the NDI SDK.
• BlackHole / Loopback on macOS appear as both input and output. App routes to output side, OBS picks it up from input side. Wrong direction = silence.
• OBS scene names are case-sensitive in the websocket protocol. Enumerate with GetSceneList for canonical spelling.
• MIDI 1.0 vs 2.0 UMP are different wire formats. Most tools speak 1.0 by default.
• OSC bundles vs single messages. TouchOSC sends bundles by default — parse {"type":"bundle"} before reaching into .elements.

Example — MIDI note 36 triggers full-stack cue

On MIDI note 36: switch OBS to scene "Main", fade DMX channel 1 up to full, recall PTZ preset 3. Use media-midi monitor piped through jq to fan out three parallel actions (obs-websocket scene-switch, media-dmx fade, ptz-visca preset-recall). Core live-production value: one event → coordinated multi-device response.

Related

• workflow-streaming-distribution — what to do with the stream once OBS emits it.
• workflow-audio-production — deeper system-audio recipes.
• workflow-broadcast-delivery — SDI + HDR dynamic metadata upstream.
• workflow-analysis-quality — monitor the live stream for drift.