Closed captions
The Dolby OptiView Live platform supports closed captions ingest and delivery. This functionality is essential for accessibility, allowing viewers to follow along with spoken content through on-screen text.
caution
This functionality is only supported through the SRT ingest protocol.
Configuring closed captions
To deliver closed captions the following steps must be taken:
- Ensure your encoder is configured to include CEA-608/708 closed caption data in the video stream.
- Within the dashboard, configure the closed captions track by selecting the channel, language, and label.
- Start your channel and begin ingesting video with embedded caption data.
- Check the preview in the dashboard to validate the captions are being received correctly.
API example
You can also configure closed captions via the API when creating or updating an ingest. Include the captions array in your request body, where each track requires a channel number and a language.
POST https://api.theo.live/v2/channels/{channelId}/ingests
{
"name": "my-ingest",
"type": "srt-pull",
"url": "srt://your-srt-source:1234",
"region": "europe-west",
"captions": [{ "channel": 1, "language": "en", "label": "English" }]
}
Feature Compatibility and Limitations
- Only CEA-608/708 embedded captions are supported.
- Captions must be embedded in the video stream by the encoder.
Ingest
| RTMP Push | RTMP Pull | SRT Pull |
|---|---|---|
| No | No | Yes |