Teaching on Zoom: Automatic Subtitle Captions on a Whiteboard

In the wake of COVID-19, faculty are looking for ways in which they can extend their original in-class teaching approaches to on-line while maintaining high accessibility.

I recently saw a request by someone using Zoom for whiteboard capability with automatic, real-time captions that have subtitles for the audio. This capability does not currently exist in Zoom's native whiteboard. However, real-time subtitles are available in presentation applications like Microsoft Powerpoint. In addition, Zoom annotations (if enabled) allow a presenter (or anyone in a Zoom room) to annotate any shared screen as if it was a Zoom whiteboard. So I came up with the following solution to the whiteboard-with-subtitltes problem. Note that other variations on this solution exist, but this particular solution was crafted to be the most generalizable and prevent the most conflicts with Zoom and Microsoft competing for access to a single microphone.

Here are a list of steps to make it happen. You can also see the video below if you prefer to see a demo of these steps.

1. Open a Zoom room on a desktop machine that runs PowerPoint 2019 or later (including Office 365 versions of PowerPoint)
• Do not share audio or video
  
2. From the Zoom room, share the desktop that powerpoint will use when it goes into full-screen mode during a presentation
   
3. Start a blank PowerPoint presentation
   
4. Click on the "Toggle Subtitles" button shown in the bottom left corner of the PowerPoint presentation
• You should now see live subtitles being added to your presentation as you speak
  
5. Join your Zoom room from a tablet device
• This time, connect with audio so that your audience listens to you through your tablet presence
• You should see the shared, blank PowerPoint screen on the tablet device
  
6. Use the "Annotations" button in the bottom left of the tablet view to open the annotations
• Note that "Annotations" has to be enabled for your Zoom room
• You can find the setting to enable Annotations in the advanced settings on your Zoom web portal
• When annotations are enabled, anyone can use them, and so make sure you trust your audience
7. Use your tablet (perhaps with stylus) to draw on the white screen provided by PowerPoint as PowerPoint subtitles below your writing
• You can use the eraser and clear (trash can) buttons to get a blank screen
  
8. If you are going to record, I recommend using "Record to Cloud" from the tablet device
• Again, the goal is to take the load off of the desktop machine that is doing the live captioning

Here is a video I put together that demonstrates the above steps: