Overview

In order to be fully accessible and compliant with WCAG 2.1 AA standards, educational multimedia are required to have audio descriptions. While users are welcome to work with vendors to pay for audio descriptions, this article describes how to create one from scratch. 

Critical Concepts

Definitions

• Audio descriptions are spoken narrations that describe key visual elements of a video such as actions, settings, or on-screen text, making the content accessible to blind or visually impaired audiences. There are two types: standard audio descriptions and extended audio descriptions. Nowadays, both standard and extended audio descriptions are narrated using text-to-speech engines within our web browsers (rather than having actors read scripts).
  • Standard audio descriptions are narrations carefully timed to fit within natural pauses in the spoken dialogue and also appear as text onscreen. Because they require careful timing to fit between dialogue without interrupting the flow of the video, producing these descriptions can be time-consuming and requires specialized skills to ensure clarity, conciseness, and relevance.
  • Extended audio descriptions are required if the pauses between pieces of spoken dialogue in the video aren't sufficient to narrate the relevant visual content. They  pause the video at certain points to allow for sufficient time.

Things to Keep in Mind

• You can only upload extended audio descriptions on the front end. At present (February 2026), Kaltura doesn't allow users to upload standard audio descriptions. That said, the vast majority of educational content requires extended audio descriptions since there often aren't enough pauses in the dialogue to fully explain the visual content. 

Steps to Take

There are three main tasks involved in generating an audio description:

1. Creating the initial file
2. Uploading it to the entry
3. Editing it in the Kaltura caption editor

Step 1: Create the Initial File

1. On your computer, open a basic text editor.

2. In your document, add the following text at the top (be sure to include the space between the lines):

WEBVTT

1
00:00:01.000 --> 00:00:02.000
Start of description.

3. Click File > Save As.
4. Name the file whatever you like, but ensure that the file ends with .vtt (e.g. audio_description.vtt).

You now have a file that Kaltura will recognize as an extended audio description. "Start of description" is just a placeholder.

Step 2: Upload the Extended Audio Description to the Entry

4. Below the media player, click the Captions tab.
5. Click Add extended audio description.
6. In the "Upload an EAD file" window that appears:
   1. Click Browse to locate and select the .vtt file you created on your computer.
   2. Click the Select Language pulldown menu to identify the language of the audio description.
   3. In the Accuracy pulldown menu, select the percentage that you believe represents its accuracy. (This will most likely be 100% since you're creating this yourself.)
   4. In the Label field, provide a name for the extended audio description. We recommend making it clear that it's an audio description, e.g. "EAD - English" or "English Extended Audio Description."
7. Click Save.

Step 3: Edit the Extended Audio Description

1. Click Edit Captions.
2. In the pull-down menu near the top of the page, select the label for your extended audio description if it's not already selected.
3. Click the play button in the media player to play the video.
4. When you come to a moment where visuals need to be described, press the pause button.
5. Click on the first timecode (the "start" timecode) and enter the timecode from the paused video. 

6. Click on the second timecode (the "end" timecode) and enter a value two seconds later than the start timecode.

7. Enter your description in the adjacent field.
8. If you have additional audio descriptions to add, hover your mouse over one of the rows and click the + Add audio description button that appears.
9. Repeat steps a-h as needed.
10. When you're done creating your extended audio description, be sure to click Save.
11. You'll be asked to update the accuracy. Select whatever value you wish and click Save again.
12. Click Back to return to the edit page.