See Understanding Techniques for WCAG Success Criteria for important information about the usage of these informative techniques and how they relate to the normative WCAG 2.0 success criteria. The Applicability section explains the scope of the technique, and the presence of techniques for a specific technology does not imply that the technology can be used in all situations to create content that meets WCAG 2.0.
All technologies that present live audio-only information
This technique relates to:
The objective of this technique is to allow users who cannot hear to be able to access real-time audio broadcasts. It is more difficult to create accurate real-time alternatives because there is little time to correct mistakes, to listen a second time or to consult someone to be sure the words are accurately reproduced. It is also harder to simplify or paraphrase information if it is flowing too quickly.
Real-time typing text entry techniques exist using stenographic and rapid typing technologies. Re-voicing speech-to-text (where a person listens to speech and then carefully re-voices it into a computer trained to their speech) is used today for telephone relay services and may be used in the future for captioning. Eventually speech-to-text with correction will be possible.
A radio station uses Web based captioning services to provide alternatives for live sporting events; the output from the service is incorporated in a viewport of the Web page which also includes a streaming audio control.
Check that a procedure and policy is in place to ensure that text alternatives are delivered in real-time.
Check that procedure and policy are working by conducting a random sample to see if text alternatives appear.
Both #1 and #2 are true.
If this is a sufficient technique for a success criterion, failing this test procedure does not necessarily mean that the success criterion has not been satisfied in some other way, only that this technique has not been successfully implemented and can not be used to claim conformance.