Audio and Video Related Content

Make audio and video related content fully accessible to vision and hearing impaired users.

Video Content with Audio (prerecorded)

Users who are deaf, hard of hearing, or having trouble understanding the audio information must be provided with a text based alternative. 

Captioning should be provided for the audio portion of a video. 

The captioning must be synchronized with the audio so that someone reading the captions could also watch the speaker and associate relevant body language with the speech. 

Example:

https://www.w3.org/WAI/media/av/captions/

Provide a text based transcript for any prerecorded video content with audio.

Audio-Only Content with No Video 

Audio files with no video are not considered multimedia. However, since audio is a non-text element one of the following text-equivalents must be provided for deaf or hearing impaired users.  

  • HTML based transcript 

  • Text transcript 

  • A text or HTML summary 

https://www.w3.org/WAI/media/av/captions/

Provide a Description of the Visual Content in Videos (prerecorded)

Provide vision impaired users access to the visual information in a synchronized media presentation.

Alternative One

One approach is to provide audio description of the video content. The audio description augments the audio portion of the presentation with the information needed when the video portion is not available. During existing pauses in dialogue, audio description provides information about actions, characters, scene changes, and on-screen text that are important and are not described or spoken in the main sound track.

Alternative Two

The second approach involves providing all of the information in the synchronized media (both visual and auditory) in text form. An alternative for time-based media provides a running description of all that is going on in the synchronized media content.

Live Audio and Real Time Presentations

Provide hearing impaired users with synchronized captions for any live audio and real time presentations.

Flashes

Ensure that video related content does not contain anything that flashes more than three times in any one second period, or the flash is below the general flash and red flash thresholds.

Allow users to access the full content of a site without inducing seizures due to photosensitivity.

Individuals who have photosensitive seizure disorders can have a seizure triggered by content that flashes at certain frequencies for more than a few flashes