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R1 Playout Clock for Mitti — User Guide

For version 0.3.2

This guide walks you through getting R1 Playout Clock for Mitti running, hooked up to Mitti, and producing all three outputs the app supports. For version info, requirements, and legal details, see the down low.

1. What it does

R1 Playout Clock for Mitti turns Mitti's OSC stream into a giant playout countdown for the entire live event production team — director, TD, A1, stage manager, lighting. Everyone watching multi-view stays in sync on every cue, with yellow/red warning colors as the clock runs out. Nobody has to ask "how long is this?" over comms.

The app is dual-purpose by design — pick the path that fits your show, or use both at once:

• NDI^® over the network — broadcast a 1920×1080 clock as an NDI source. Picked up directly by NDI-capable software switchers (vMix, OBS, NDI Studio Monitor) and NDI-native AV systems, or via NDI-to-SDI converters (BirdDog, Kiloview, AJA) into your favourite hi-res switcher — Barco E2 / S3, Spyder X80, PixelHue Q8 / F4 / F8, etc.
• HDMI from the Mac — run the clock app full-screen on a second display and plug that HDMI straight into your favourite hi-res switcher or any HDMI-capable monitor wall. No network configuration at all.

Plus an OSC forwarder as a bonus utility — Mitti can only feed one OSC destination natively, so the app re-broadcasts every packet to a downstream listener like Bitfocus Companion. Handy when Companion needs Mitti's data too. (This isn't a clock output; it's a separate utility feature.)

2. Install

1. You'll receive a .zip in your trial email. Download it and double-click to unzip.
2. Drag R1 Playout Clock for Mitti.app into your /Applications/ folder.
3. Double-click the app to launch it.

The first time you open the app, macOS may ask you to confirm because it's downloaded from the internet — click Open in that dialog. Future launches skip this step.

3. Set up Mitti to send OSC

Mitti needs to be told where to send OSC. In Mitti:

1. Open Preferences → OSC.
2. Enable OSC Feedback.
3. Set the feedback port to 9999 (the clock's default).
4. Set the feedback target:
   • Same Mac as the clock → 127.0.0.1
   • Different Mac → that Mac's IP address on your network. Both machines must be on the same network.

Once Mitti starts playing a cue, the clock's status bar should show OSC live and the time fields should start updating.

4. The interface at a glance

• Stage — the clock display itself (Elapsed / Remaining / TRT, plus a progress bar).
• Status bar at the bottom — OSC status dot, NDI status dot, NDI sender stats when running, and the version number on the right.
• Settings panel ⚙ — slides in from the right when you click the gear icon in the top-right of the stage.

5. Settings

All settings live in one panel, organized into five sections: OSC Input, OSC Forwarding, NDI Output, Display, and About. Most changes take effect immediately. Anything that needs an Apply button is noted below.

5.1 OSC Input

• Listen Port — UDP port the clock listens on. Must match Mitti's feedback port. Default 9999.
• Elapsed Address — defaults to /mitti/cueTimeElapsed.
• Remaining Address — defaults to /mitti/cueTimeLeft.
• Duration Address — leave blank for Mitti. Mitti has no real cue-duration OSC address, so the clock derives Total automatically from Elapsed + Remaining.

Click Apply to restart the OSC listener with the new settings.

5.2 OSC Forwarding

Mitti can only feed one OSC destination at a time. If you also want Companion (or another OSC consumer) to see the same Mitti packets, enable forwarding here. The clock receives Mitti's stream, drives the display, and re-broadcasts every packet verbatim to the destination below.

• Enable forwarding — checkbox to turn it on or off.
• Destination IP — where to forward to. 127.0.0.1 for the same Mac, or a LAN IP for another machine.
• Destination Port — the port the downstream listener is on (e.g. Companion's OSC server port).

Click Apply to start or stop forwarding. The status line below updates once per second and shows one of: "forwarding: disabled", "forwarding to 192.0.2.10:8000 — N sent", or "forwarding error: …".

5.3 NDI Output

The NDI feed is a 1920×1080 progressive Full NDI^® source — uncompressed BGRA, not NDI HX. Both Full NDI and NDI HX receivers can ingest it.

• Source Name — how this NDI feed appears in NDI receivers. Default Mitti Clock.
• Frame Rate — match this to your program output. Choices include 23.976, 24, 25 (PAL), 29.97 (NTSC, default), 30, 50, 59.94, 60.
• NDI Clock Size — size of the clock digits in the 1920×1080 NDI feed (default 350). Independent of the operator window's size — tune the NDI feed for the surface receivers will display it on (video wall, FOH monitor, etc.) without affecting your close-up operator view. Applies on the next Start NDI.

Click Start NDI to begin broadcasting. The button changes to Stop NDI while running, and the status bar shows NDI on with a sent / dropped counter.

On the receiving side, open NDI Studio Monitor (or OBS with obs-ndi, or vMix's NDI input). The source named above will appear in the NDI source list once Start NDI has been clicked.

5.4 Display

• Layout — Side by side or Stacked. Stacked is the default; works better on tall, narrow displays and second-screen outputs. Side by side fits a wider operator monitor.
• Operator Clock Size — base size in pixels for the digits in the operator window (default 350). The clock auto-scales with window height; this is the size at 1080-tall. Separate from the NDI Clock Size in the NDI Output section.
• Accent Color — color of the time digits when running normally.
• Show fields — independently toggle Elapsed, Remaining, TRT, the progress bar, and the Now-playing pill. Hide what you don't want on screen or in the NDI feed.

5.5 About

Shows the app version, NDI^® attribution (NDI^® is a registered trademark of Vizrt NDI AB), and a link to the down-low page for full credits and licenses.

6. Running a show

1. Open the clock app.
2. Confirm the status bar shows the OSC indicator going live once Mitti starts playing a cue.
3. If you want NDI output, open Settings, set the source name and frame rate, click Start NDI.
4. If Companion (or another OSC consumer) needs Mitti's stream too, enable OSC Forwarding with the destination IP and port. Click Apply and watch the N sent counter climb.
5. Drag the clock window to the display you want, or fullscreen it via the OS-level window controls.
6. Start cues in Mitti. The on-screen clock, NDI output, and any forwarded OSC all carry the same data.

7. Troubleshooting

Status bar shows "no OSC" and never goes live

Mitti isn't sending OSC, or it's sending to the wrong place. Check:

• OSC Feedback is enabled in Mitti's preferences (not just the port filled in).
• The feedback target in Mitti is correct (127.0.0.1 for same Mac; otherwise the IP of the Mac running the clock).
• The feedback port in Mitti matches the clock's listen port (default 9999).
• Mitti is actively playing a cue — Mitti only sends OSC feedback during playback.

"Cannot bind to port" error

Another app is already using the listen port. Either quit that app, or change the clock's listen port in Settings → OSC Input (and update Mitti's feedback port to match).

Receiving OSC from another Mac, but no data arriving

Both machines need to be on the same network, and macOS's firewall on the clock Mac must allow incoming UDP on the listen port. Check System Settings → Network → Firewall.

NDI source doesn't show up in OBS / vMix / Studio Monitor

• Make sure Start NDI was clicked — the status bar should show NDI on.
• Confirm the receiving app is on the same network as the clock Mac. NDI relies on multicast / discovery on the local subnet; it doesn't cross routers without additional configuration.
• Check the source name. It's whatever is set in the Settings panel under NDI Output → Source Name. The full discovery name shown in receivers usually combines the Mac's name with the source name.
• If the receiver supports an NDI Discovery Server, make sure both ends are using the same one (or both have discovery server disabled and rely on local broadcast).

OSC Forwarding shows an error

The status line under the OSC Forwarding section reports errors as "forwarding error: …". Most common causes:

• Destination IP unreachable — wrong address, or the downstream machine is offline.
• Destination port closed — the downstream OSC consumer isn't actually listening there. Forwarding will report the error but won't affect the clock display.
• Network or firewall blocking outbound UDP. Less common, but worth checking on locked-down networks.

Times look wrong (e.g. negative or huge)

Confirm in Settings → OSC Input that the addresses match what Mitti is actually sending. Mitti's defaults match the clock's defaults — only change them if you've customized Mitti's OSC output.

Color warnings (yellow / red) don't appear

The warnings trigger only when Remaining is at or below 10 seconds and above 0. If Remaining is 0 (no cue playing) or above 10 seconds, the value stays in the normal accent color.

8. Getting help

If something's not working and the troubleshooting above didn't sort it, reply to your trial email — that's the fastest way to reach us during the testing period. For anything else, see the contact page.