How to Build a Local Translation Server on Mac Mini | Real-Time On-Device AI

Recommended Hardware & Audio Input

To ensure smooth performance when running Language Models for transcription & translation, we recommend the following specifications:

• Processor: Apple Silicon is required (M1 or higher). The Neural Engine in these chips is what handles the AI processing.
• Memory (RAM): 16GB is highly recommended for "Multilingual" models to prevent lag during long sessions.
• Audio Input: MacOS should recognizes the source as a Microphone/Input device, the software will work.
  
  • Pro Tip: Use a high-quality USB Audio Interface or an XLR-to-USB converter to bring clean audio from the room’s sound mixer into the Mac Mini.
  • Verification: Go to System Settings > Sound > Input. Ensure the input level bars move when audio is played.

Initial Setup & Activation

1. Install: Download the latest version of ConferenceCaptioning from the Mac App Store.
2. Activate Premium:
   
   • Open the app → Select Event Organizer.
   • Click the Info button (top right) → Select Activate.
   • Log in or Sign Up. Once done, "Allow" the browser to redirect back to the app. You should see "Premium Stream Activated."
3. Download AI Models:
   
   • Check the box "Use On-Device AI".
   • Set Accuracy to Multilingual. This is crucial for being able to swap between languages (Eg: Arabic-to-English & English-to-Arabic)
   • Click Download AI Model. This may take a few minutes depending on your internet speed.

Once the base AI model is ready, you need to configure the specific translation pair:

1. Select the language you wish to translate into (e.g., Arabic) and click Create Premium Stream.
2. On the Stream page, check the box for Translation+.
3. Download the Translation Model: Specifically download the Arabic and English modules until the status shows "Active."
4. Set the Direction: Toggle the languages correctly. Eg: It should read "Arabic to English" for Arabic-to-English translation
5. Go Live: Tap Start Live Streaming.
6. The QR Code: Expand the QR code. You can print this or display it on the classroom door; it will remain the same for this stream. Check "Start streaming immediately" to bypass the landing page for students.

Remote Management (The "Headless" Server)

Because the Mac Mini often sits in a server rack without a monitor, you can manage it from any laptop/tablet/device on the same local network.

1. On the Mac Mini app, click the Info (i) button on the Stream Page.
2. Copy the provided URL (e.g., http://192.168.1.50:8080/index.html).
3. Replace the word index in the URL with control (e.g., http://192.168.1.50:8080/control.html).
4. Open this URL on your phone or laptop. You can now Swap Languages (English ↔ Arabic) or Start/Stop the stream remotely without needing a mouse or keyboard attached to the Mac.

Automation: Auto-Restart on Power Failure

To ensure the translation service is always available even after a power outage or system reboot:

1. Create a new text file named "auto-restart.sh"
2. Paste the contents of this GitHub gist into the file
3. Open Terminal and run "sh auto-restart.sh"
4. This script monitors the app and ensures that if the Mac Mini reboots, the software launches and resumes streaming automatically.

Depending on your classroom setup, you have two ways to show the translations:

• For Students: They simply get the stream URL or scan the QR code and watch the live translations & transcript on their own devices (phones/tablets).
• For In-Room Displays:
  
  • Simple: Use our Slide Deck Overlay guide to show captions over a Canva/Slides/Keynote.
  • Advanced: Use ProPresenter integration for professional-grade video mixing on auditorium screens.