Close_caption setting on livestream status Meeting API call

[ruben.gaspar.aparici (Ruben)]

Dear All,

I’m trying to make use of the close_caption setting in the Meetings REST API [1]. Since we have an in-house Wowza infrastructure, we’d like to provide Zoom captions during our webcast events when they originate from Zoom meetings or webinars.

To do this, I need to understand which standard is used to embed captions in the stream, and how I should configure my Wowza application to support and display them correctly. Currently, this isn’t working as expected—when using standard HLS players [2], I only see very small caption fragments displayed at the top of the screen.

Thank you,
Ruben

[2] hls.js demo
[1] Meetings APIs

[gianni.zoom (Gianni)]

@ruben.gaspar.aparici

To do this, I need to understand which standard is used to embed captions in the stream, and how I should configure my Wowza application to support and display them correctly. Currently, this isn’t working as expected—when using standard HLS players [2], I only see very small caption fragments displayed at the top of the screen.

Hi @ruben.gaspar.aparici ,

This is a good question. Zoom automated captions are based on transcription from automated speech recognition. I believe it is relaying what one would receiving in the VTT or TXT files for speakers. However, I believe 708 is being used because you have the ability to customize the captions
in a meeting or webinar.

Here’s a closed captioning guide that could also be useful: Live Streaming with RTMP - #4 by MaxM

There may be a few UI differences in the references, but it should be generally accurate still.