Section 508 Web Standards
(b) Equivalent alternatives for any multimedia presentation shall be synchronized with the presentation.
What does it mean?
Multimedia includes video, audio, music, Flash animation, real-time streaming media, and prerecorded audio and video presentations. Captioning for the audio portion and audio description of visual information of multimedia presentations are considered equivalent alternatives. When an audio portion of a multimedia production is captioned, as required, the captioning must be synchronized with the audio. Synchronized captioning would be required so someone reading the captions could also watch the speaker and associate relevant body language with the speech.
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How to evaluate
Synchronized captions are provided for video, Flash animations, and audio/visual presentations. Audio presentations only (with no video) are not required to be synchronized; a text transcript will suffice. A silent web slide show does not require audio description, but would need accompanying text alternatives associated with the graphics.
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Design Resources