Adhere - TTML2 Audio Description Implementation

What this is and how to use it

Adhere is a demonstration page for the adhere-lib ES6 implementation of the audio features of TTML2. The library uses the Web Audio API and the Web Speech API, with timing events cued using Text Track Cues.

This page demonstrates Adhere in a client-side browser-based video player.

To use it, for each of Video and TTML, choose whether you want one of the provided samples, or one from your local file system or a URL, choose which one, and click the appropriate "Load" button. When video and TTML have both been loaded, press Play in the video to see and hear the results.

Demo TTML2 files are provided for the Adhere demo video. Alternatively the TTML2 test suite is also provided.

This page has some limitations: relative paths from local file links to TTML2 files are not honoured; in that case resources must have absolute paths. This limitation does not apply to served TTML2 files where the URL is provided.

Select inputs

Video file

Adhere Demo Video:

Local file:

URL:

Click "Load Video" to load chosen video.

TTML2 file

Adhere demo and TTML2 tests:

Local file:

URL:

Debug options

Cache <audio> resources (helps with playback of many <audio> elements with the same source URL on Firefox)

Click "Load TTML" to load chosen TTML.

Player

AD volume:

Currently active:

Logs:

Enable logging

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