Captions - Providing Text Alternatives for Multimedia (pre-recorded)
Shawn Sandy (Ally.Cafe) ~
Captions (prerecorded)
Captions are a text alternative for multimedia content that is synchronized with the audio and visual content. They provide a textual representation of the spoken words, sound effects, and other relevant audio information. Captions are essential for making multimedia content accessible to individuals who are deaf or hard of hearing, as well as those who prefer or need to consume content without audio.
WCAG 2.2 Guidelines
The Web Content Accessibility Guidelines (WCAG) 2.2 provide specific guidelines related to captions for prerecorded multimedia content:
1.2.2 Captions (Prerecorded) (Level A): Captions are provided for all prerecorded audio content in synchronized media, except when the media is a media alternative for text and is clearly labeled as such.
This guideline ensures that individuals who are deaf or hard of hearing can access the auditory information in prerecorded multimedia content.
Purpose and Best Practices
The purpose of providing captions for prerecorded multimedia content is to ensure equal access to information and entertainment for individuals with hearing impairments or those who prefer or need to consume content without audio.
Best practices for implementing captions include:
- Providing accurate and complete captions that capture all spoken words, sound effects, and other relevant audio information.
- Synchronizing captions with the corresponding audio and visual content.
- Ensuring that captions are easily readable and legible, with appropriate font size, color contrast, and positioning.
- Providing options for users to adjust caption settings, such as font size, color, and background opacity.
- Offering captions in multiple languages, if applicable, to accommodate diverse audiences.
Code Examples
<!-- Example 1: Using the <track> element to provide captions for a video -->
<video src="video.mp4" controls>
<track src="captions.vtt" kind="captions" srclang="en" label="English Captions">
</video>
This example demonstrates how to use the <track> element to provide captions for a video. The kind attribute is set to “captions”, and the srclang attribute specifies the language of the captions. The label attribute provides a user-friendly name for the captions.
<!-- Example 2: Using the aria-describedby attribute to associate captions with audio -->
<audio src="audio.mp3" controls aria-describedby="audio-captions"></audio>
<div id="audio-captions">
<p>[Music]</p>
<p>Speaker 1: Welcome to the podcast.</p>
<p>Speaker 2: Thank you for having me.</p>
</div>
This example shows how to use the aria-describedby attribute to associate captions with an audio element. The aria-describedby attribute references the ID of the element containing the captions, providing a programmatic relationship between the audio and its captions.
<!-- Example 3: Providing a transcript for a video -->
<video src="video.mp4" controls></video>
<div>
<h2>Video Transcript</h2>
<p>[Visual description of the video]</p>
<p>Speaker 1: Welcome to the tutorial.</p>
<p>Speaker 2: In this video, we'll learn about...</p>
</div>
In this example, a transcript is provided for a video. While not strictly captions, a transcript can serve as an alternative for users who prefer to read the content instead of watching the video. The transcript should include all relevant visual and auditory information.
Relevant Resources
Understanding WCAG 2.2 Success Criterion 1.2.2: Captions (Prerecorded)
Web Accessibility Initiative (WAI) - Audio and Video Content
3Play Media - Closed Captioning Resources
Summary
By following the WCAG 2.2 guidelines and implementing best practices for captions, you can ensure that your prerecorded multimedia content is accessible to individuals with hearing impairments and provide an inclusive experience for all users. Captions (prerecorded)
1.2.5 Audio Description (Prerecorded)
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