New Feature: Closed Captions for videos
ArcGIS StoryMaps now supports closed captions for videos! This new capability helps members of your audience with low or impaired hearing and improves the accessibility of your content.
How to add closed captions
Upload a video to your story or briefing.
Once the video is uploaded, open the Video options.
In the Accessibility tab, click the Upload closed captions button.
Choose the corresponding .vtt file for the uploaded video from the file picker.
Click Save in the Video options window.
The closed captions have been added to the video player!
Expected support
Some things to note about this feature:
You can provide captions via a WebVTT file for uploaded videos. If you are using videos from a 3rd party service, like Vimeo or YouTube, you may be able to add captions through that service.
Any added closed captions are on by default on the videos until the reader turns off the closed captions.
Videos uploaded directly to collections do not support adding closed captions.
Captions are not currently supported for cover videos. Please let us know in the comments if you would like this to be added in the future and how you would use it.
Closed captions file formatting
ArcGIS StoryMaps supports WebVTT (Visual Text Track) files to be uploaded for closed captions. This text document outlines the text narrations and descriptions, and the times throughout the video they should be displayed.
The WebVTT files must be created externally and then uploaded for each video that requires captions. This file must be created for the specific video file it is referencing, as the content within the closed caption file will not be checked against the video for which it is uploaded.
WebVTT files must adhere to the standard format defined by the W3C here: W3C: WebVTT: The Web Video Text Tracks Format. If you upload a WebVTT file and captions do not work as expected please verify the validity and formatting of the file.
Styling Closed caption text
Through CSS additions to your WebVTT file, closed captions can use certain styling like bolding text, underlining, or changing the positioning of the caption within the video. Check out the WebVTT creation tutorials/tricks section below for more information on how to take advantage of these formatting techniques.
External resources
If you don’t already have a WebVTT closed caption file for your desired video, there are many places to create and validate them! Here are some options for other locations on the web to support your .vtt file creation/validation process:
WebVTT support documentation
.VTT file requirements - W3C Candidate Recommendation
The official documentation regarding the formatting of a successfully parsed WebVTT file
WebVTT creation tutorials/tricks
Web Video Text Tracks Format (WebVTT) - mdn web docs
This page walks through the individual lines of the WebVTT file, the caption (also called cue) creation, and the basic styling options of the lines.
Improving Video Accessibility with WebVTT - CSS-Tricks
This blog provides a more basic overview of the WebVTT format, with visual examples of different styling implementations.
Controlling Captions with WebVTT - meryl.net
Meryl Evans, an accessibility consultant, gives an example of simple captions, with a bit of input on how to keep the styling of your captions accessible.
WebVTT validator
Copy and paste the content of your WebVTT file into this live validator to check the formatting of the file and ensure the captions will play as expected