An alternative for time-based media or audio description of the prerecorded video content is provided for synchronized media, except when the media is a media alternative for text and is clearly labeled as such. (Level A)
Intention of 1.2.3 Audio Description or Media Alternative (Prerecorded)
In a video presentation, people who are blind or those who have visual challenges miss the information that is conveyed through visuals alone. The video only information include the pauses due to actions, characters, scene changes, and on-screen text that are important and are not described or spoken in the main sound track. 1.2.3 Audio Description or Media Alternative (Prerecorded)success criterian helps addressing this problem. The approaches available to solve this problem are
1 Providing audio description of the video content: The audio description supplement’s information conveyed through actions, characters, scene changes, and on-screen text available during the dialog pauses and which is conveyed only through visuals. Eg: The advertisements on the television that says, Order our product through the telephone numbers displayed on the screen. This information should be spoken out so that the viewers with blindness and visual challenges too benefit.
2.Providing the information available in the synchronized media in text form: This alternate for the time-based media provides the entire description of the synchronized media content not just restricted to the content during pauses like the audio description. Full descriptions are provided of all visual information, including visual context, actions and expressions of actors, and any other visual material. In addition, non-speech sounds (laughter, off-screen voices, etc.) are described, and transcripts of all dialogue are included. The sequence of description and dialogue transcripts are the same as the sequence in the synchronized media itself. The alternate for the time-based media also takes care of the interactions in the synchronized media.
In the two approaches described above the alternate for time-based media is a better one as
- Alternate for time-based media describes all the dialogs of the synchronized media including visual contexts, actions, expressions of actors etc.
- Alternate for time-based media also takes care of the non speech sounds such as laughters, off-screen voices etc.
- The dialogs and descriptions in the synchronized media are same in sequence with the alternate for time-based media.
- The interactions available as part of the synchronized media can also be taken care with alternate for time-based media.
Who benefits with 1.2.3 Audio Description or Media Alternative (Prerecorded)
- People with blindness and visual impairment.
- People with deafness or hard of hearing benefit with alternate for time-based media that is available in text form.
WCAG 2.0 techniques for 1.2.3 Audio Description or Media Alternative (Prerecorded)
- G58: Placing a link to the alternative for time-based media immediately next to the non-text content
- H53: Using the body of the object element (HTML)
- G78: Providing a second, user-selectable, audio track that includes audio descriptions
- G173: Providing a version of a movie with audio descriptions using one of the following
- G8: Providing a movie with extended audio descriptions using one of the following
- G203: Using a static text alternative to describe a talking head video