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
Providing Text Transcript to Embedded Video Related Content
You can do one of the following.
1. Place the Transcript Next to the Video
Here is an example of how we have incorporated this to http://sf.gov .
2. Provide a Link to the Transcript
Provide a link to the transcript that is placed in close proximity to the video (example: "View video transcript")
This link could either expand and show the transcript on the page or link to a new page.
Obtaining a Transcript from YouTube
Here are the steps involved with getting the video transcript from YouTube.
Editing the Automated Transcript
Because the automatic transcript only transcribes the audio, you will need to manually review and edit.
Fix typos and errors.
Remove extra line breaks and create logical paragraphs.
Add any text that is displayed visually in your video but not spoken, such as title screens.
Indicate who is talking, especially if there is more than one speaker in the video.