One of the most common questions we receive is “if I have this kind of media, which properties should I set?” This page endeavors to answer that in as clear a way as possible for both the absolute must-have properties and the optional. It’s easiest to look at these for each class of content.
- Audio
- Video
- Web pages
- Electronic Books
- Web Applications
- Mobile applications
Terms that are used on this page, which are defined further in the Access for All specifications and the best practices guide, include the following. Note that there is a great web accessibility page that describes these terms in much more detail.
- Captioned: Captions are text versions of the spoken word. Captions allow the content of web audio and video to be accessible to those who do not have access to audio. Though captioning is primarily intended for those who cannot hear the audio, it has also been found to help those that can hear audio content and those who may not be fluent in the language in which the audio is presented.
- AD – Audio Description: Audio descriptions provide additional information about what is visible on the screen. This allows video content to be accessible to those with visual disabilities. (Note: we need to describe extended vs.non-extended descriptions)
- Transcript: Transcripts also provide an important part of making web multimedia content accessible. Transcripts allow anyone that cannot access content from web audio or video to read a text transcript instead. Transcripts do not have to be verbatim accounts of the spoken word in a video. They can contain additional descriptions, explanations, or comments that may be beneficial.
Note that we are trying to support all of the types of media that may be used with accessibility in mind. While many of these are electronic, there are also a number of physical forms that would be described in a catalog page, but delivered through physical means. If you have an interesting content type, please relate it in comments, which we have enabled for this page for a short time until June 19, or in the google groups discussion.
On this page:
- Audio that lacks captions
- Audio with captions
- Audio with transcript
- HTML document with images, has text description
- HTML document with images, lacks text description
- HTML Interactive with images, has text description, mouse & keyboard accessible
- HTML interactive with images, lacks text description, mouse & keyboard accessible
- HTML interactive with images, lacks text description, requires mouse
- HTML interactive with sound & images, lacks text description, requires mouse
- Image with text description
- Image with text description, with color-coding
- Image without text description
- Interactive without sound, keyboard or mouse accessible, lacks image description
- Interactive without sound, mouse required, lacks image description
- Interactive without sound, mouse required, with image description
- PDF with images and text description
- PDF with images, lacks text description
- PDF with no images
- PDF with scanned image of text
- Text with no images
- Video that has no audio
- Video that lacks captions
- Video with CC
- Video with CC and AD (non-extended)
- Video with CC and extended AD
- Video with CC and transcript
- Video with CC, transcript, and AD (non-extended)
- Video with CC, transcript, and extended AD
- Video with transcript
HTML document with images, has text description
Should have transformable text. Description of images might be in content itself, not alt text.
- Access Modes
-
- textual
- visual
- Media Features
-
- alternativeText
- displayTransformability
Example
<meta itemprop="accessMode" content="textual"/>
<meta itemprop="accessMode" content="visual"/>
<meta itemprop="mediaFeature" content="alternativeText"/>
<meta itemprop="mediaFeature" content="displayTransformability"/>
HTML document with images, lacks text description
Should have transformable text.
- Access Modes
-
- textual
- visual
- Media Features
-
- displayTransformatability
Example
<meta itemprop="accessMode" content="textual"/>
<meta itemprop="accessMode" content="visual"/>
<meta itemprop="mediaFeature" content="displayTransformability"/>
HTML Interactive with images, has text description, mouse & keyboard accessible
Should have transformable text.
Schema.org Object: WebApplication
- Access Modes
-
- textual
- visual
- Media Features
-
- altText
- longDescription
- displayTransformatability
- Control Flexibility
-
- fullKeyboardControl
- fullMouseControl
Example
<meta itemprop="accessMode" content="textual"/>
<meta itemprop="accessMode" content="visual"/>
<meta itemprop="mediaFeature" content="alternativeText"/>
<meta itemprop="mediaFeature" content="longDescription"/>
<meta itemprop="mediaFeature" content="displayTransformability"/>
<meta itemprop="controlFlexibility" content="fullKeyboardControl"/>
<meta itemprop="controlFlexibility" content="fullMouseControl"/>
HTML interactive with images, lacks text description, mouse & keyboard accessible
Should have transformable text.
Schema.org Object: WebApplication
- Access Modes
-
- textual
- visual
- Control Flexibility
-
- fullKeyboardControl
- fullMouseControl
Example
<meta itemprop="accessMode" content="textual"/>
<meta itemprop="accessMode" content="visual"/>
<meta itemprop="controlFlexibility" content="fullKeyboardControl"/>
<meta itemprop="controlFlexibility" content="fullMouseControl"/>
HTML interactive with images, lacks text description, requires mouse
Should have transformable text.
- Access Modes
-
- textual
- visual
- Control Flexibility
-
- fullMouseControl
Example
<meta itemprop="accessMode" content="textual"/>
<meta itemprop="accessMode" content="visual"/>
<meta itemprop="controlFlexibillity" content="fullMouseControl"/>
HTML interactive with sound & images, lacks text description, requires mouse
Should have transformable text.
- Access Modes
-
- auditory
- textual
- visual
- Control Flexibility
-
- fullMouseControl
Example
<meta itemprop="accessMode" content="auditory"/>
<meta itemprop="accessMode" content="textual"/>
<meta itemprop="accessMode" content="visual"/>
<meta itemprop="controlFlexibility" content="fullMouseControl"/>
Image with text description
Image files with text descriptions built-in or in an html alternative to a flash slideshow. No color-coding or important text on image.
- Access Modes
-
- visual
- Media Features
-
- longDescription
Example
<meta itemprop="accessMode" content="visual"/>
<meta itemprop="mediaFeature" content="longDescription"/>
Image with text description, with color-coding
Image that has a text alternative. Image contains information encoded in color.
- Access Modes
-
- visual
- color
- Media Features
-
- longDescription
Example
<meta itemprop="accessMode" content="color"/>
<meta itemprop="accessMode" content="visual"/>
<meta itemprop="displayTransformability" content="fullMouseControl"/>
Image without text description
Image with no alternative text available. No color-coding or important text on image.
- Access Modes
-
- visual
Example
<meta itemprop="accessMode" content="visual"/>
Interactive without sound, keyboard or mouse accessible, lacks image description
Non-html interactive, text not transformable, lacks text description of images.
- Access Modes
-
- textual
- visual
- Display Transformability
-
- fullKeyboardControl
- fullMouseControl
Example
<meta itemprop="accessMode" content="textual"/>
<meta itemprop="accessMode" content="visual"/>
<meta itemprop="displayTransformability" content="fullKeyboardControl"/>
<meta itemprop="displayTransformability" content="fullMouseControl"/>
Interactive without sound, mouse required, lacks image description
Non-html interactive, text not transformable, lacks text description of images.
- Access Modes
-
- textual
- visual
- Display Transformability
-
- fullMouseControl
Example
<meta itemprop="accessMode" content="textual"/>
<meta itemprop="accessMode" content="visual"/>
<meta itemprop="displayTransformability" content="fullMouseControl"/>
Interactive without sound, mouse required, with image description
Non-html interactive, text not transformable, with alternate text description of images.
- Access Modes
-
- textual
- visual
- Media Features
-
- longDescription
- Display Transformability
-
- fullMouseControl
Example
<meta itemprop="accessMode" content="textual"/>
<meta itemprop="accessMode" content="visual"/>
<meta itemprop="mediaFeature" content="longDescription"/>
<meta itemprop="displayTransformability" content="fullMouseControl"/>
PDF with images and text description
PDF with readable text, with images that have text description OR the document text is sufficient to replace the images.
- Access Modes
-
- textual
- visual
- Media Features
-
- longDescription
Example
<meta itemprop="accessMode" content="textual"/>
<meta itemprop="accessMode" content="visual"/>
<meta itemprop="mediaFeature" content="longDescription"/>
PDF with images, lacks text description
A PDF where the text is readable by screen reader, but images lack text description and the document text is not sufficient to replace the images.
- Access Modes
-
- textual
- visual
Example
<meta itemprop="accessMode" content="textual"/>
<meta itemprop="accessMode" content="visual"/>
PDF with no images
PDF with only text, which is readable by screen reader.
- Access Modes
-
- textual
Example
<meta itemprop="accessMode" content="textual"/>
PDF with scanned image of text
Scanned image of a text document, but no screen-reader readable text (i.e. historic document). May have images lacking text description.
- Access Modes
-
- visual
- textOnImage
Example
<meta itemprop="accessMode" content="textOnImage"/>
<meta itemprop="accessMode" content="visual"/>
Text with no images
Text, Word, spreadsheet, any character-based doc with no images
- Access Modes
-
- textual
Example
<meta itemprop="accessMode" content="textual"/>
Video that has no audio
Video with no audio track; it doesn’t need captions. No audio description.
- Access Modes
-
- visual
Example
<meta itemprop="accessMode" content="visual"/>
Video that lacks captions
Video that has a meaningful sound track but does not have captions (or audio descriptions).
- Access Modes
-
- auditory
- visual
Example
<meta itemprop="accessMode" content="auditory"/>
<meta itemprop="accessMode" content="visual"/>
Video with captions
Video with audio track and captions. No audio description.
- Access Modes
-
- auditory
- visual
- Media Features
-
- captions
Example
<meta itemprop="accessMode" content="auditory"/>
<meta itemprop="accessMode" content="visual"/>
<meta itemprop="mediaFeature" content="captions"/>
Video with captions and AD (non-extended)
Video with sound track, captions and non-extended audio description.
- Access Modes
-
- auditory
- visual
- Media Features
-
- audioDescription
- captions
Example
<meta itemprop="accessMode" content="auditory"/>
<meta itemprop="accessMode" content="visual"/>
<meta itemprop="mediaFeature" content="audioDescription"/>
<meta itemprop="mediaFeature" content="captions"/>
Video with captions and extended AD
Video with audio track, captions and extended audio description (audio begins before visuals or pauses visuals in the middle).
- Access Modes
-
- auditory
- visual
- Media Features
-
- audioDescription
- captions
Example
<meta itemprop="accessMode" content="auditory"/>
<meta itemprop="accessMode" content="visual"/>
<meta itemprop="mediaFeature" content="audioDescription"/>
<meta itemprop="mediaFeature" content="captions"/>
Video with captions and transcript
Video with audio track, captions and text of video in separate doc or pane.
- Access Modes
-
- auditory
- textual
- visual
- Media Features
-
- captions
- transcript
Example
<meta itemprop="accessMode" content="auditory"/>
<meta itemprop="accessMode" content="textual"/>
<meta itemprop="accessMode" content="visual"/>
<meta itemprop="mediaFeature" content="captions"/>
<meta itemprop="mediaFeature" content="transcript"/>
Video with captions, transcript, and AD (non-extended)
Video with audio track captions, text of video in separate doc or pane, and non-extended audio description.
- Access Modes
-
- auditory
- textual
- visual
- Media Features
-
- audioDescription
- captions
- transcript
Example
<meta itemprop="accessMode" content="auditory"/>
<meta itemprop="accessMode" content="textual"/>
<meta itemprop="accessMode" content="visual"/>
<meta itemprop="mediaFeature" content="audioDescription"/>
<meta itemprop="mediaFeature" content="captions"/>
<meta itemprop="mediaFeature" content="transcript"/>
Video with captions, transcript, and extended AD
Video with audio track, captions, text of video in separate doc or pane, and audio description.
- Access Modes
-
- auditory
- textual
- visual
- Media Features
-
- audioDescription
- captions
- transcript
Example
<meta itemprop="accessMode" content="auditory"/>
<meta itemprop="accessMode" content="textual"/>
<meta itemprop="accessMode" content="visual"/>
<meta itemprop="mediaFeature" content="audioDescription"/>
<meta itemprop="mediaFeature" content="captions"/>
<meta itemprop="mediaFeature" content="transcript"/>
Video with transcript
Text of video in separate doc, not captions
- Access Modes
-
- auditory
- visual
- Media Features
-
- transcript
Example
<meta itemprop="accessMode" content="auditory"/>
<meta itemprop="accessMode" content="visual"/>
<meta itemprop="mediaFeature" content="transcript"/>