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<!DOCTYPE html><html lang="en" xml:lang="en" xmlns="http://www.w3.org/1999/xhtml"><head><title>G157: Incorporating a live audio captioning service into a Web page | WAI | W3C</title> <meta name="viewport" content="width=device-width, initial-scale=1"> <link rel="stylesheet" href="https://w3.org/WAI/assets/css/style.css"> <link rel="stylesheet" href="../base.css"> </head><body dir="ltr"> <a href="#main" class="button button--skip-link">Skip to content</a> <div class="minimal-header-container default-grid"> <header class="minimal-header" id="site-header"> <div class="minimal-header-name"> <a href="https://www.w3.org/WAI/WCAG22/Techniques/">WCAG 2.2 Techniques</a> </div> <div class="minimal-header-subtitle">Examples of ways to meet WCAG; not required</div> <a class="minimal-header-link" href="https://www.w3.org/WAI/WCAG22/Techniques/about">About WCAG Techniques</a> <div class="minimal-header-logo"> <a href="http://w3.org/" aria-label="W3C"> <svg xmlns="http://www.w3.org/2000/svg" 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45.5h-1.816l-2.784-9.355c-.41-1.394-.65-2.334-.722-2.823-.104.749-.332 1.71-.684 2.881L129.04 45.5h-1.817l-3.779-14.277h1.875l2.217 8.72c.3 1.14.527 2.272.684 3.399.143-1.068.397-2.237.761-3.506l2.52-8.613h1.855l2.627 8.681c.339 1.127.6 2.272.781 3.438.105-.899.336-2.038.694-3.418l2.207-8.701h1.875zm14.57 0l-1.718-4.424h-5.664l-1.7 4.424h-1.816l5.576-14.336h1.621l5.567 14.336zm-2.256-6.016l-1.601-4.326-.684-2.138c-.195.78-.4 1.494-.615 2.138l-1.621 4.326zm10.098 6.016h-5.156v-1.035l1.68-.381V32.658l-1.68-.4v-1.035h5.156v1.035l-1.68.4v11.426l1.68.38z"></path> </g> </g> </svg> </a> </div> </header> </div> <div class="default-grid with-gap leftcol"> <aside class="box nav-hack sidebar standalone-resource__sidebar"> <header class="box-h">Page Contents</header> <div class="box-i"> <nav aria-label="page contents" class="navtoc"> <ul><li><a href="#technique">About this Technique</a></li> <li><a href="#description">Description</a></li> <li><a href="#examples">Examples</a></li> <li><a href="#resources">Related Resources</a></li> <li><a href="#related">Related Techniques</a></li> <li><a href="#tests">Tests</a></li> </ul> </nav> </div> </aside> <main id="main" class="standalone-resource__main"> <h1><span>Technique G157:</span>Incorporating a live audio captioning service into a Web page</h1> <section id="technique" class="box"> <h2 class="box-h box-h-icon">About this Technique</h2> <div class="box-i"> <p> This technique relates to <a href="https://www.w3.org/WAI/WCAG22/Understanding/audio-only-live">1.2.9: Audio-only (Live)</a> (<strong>Sufficient</strong>).</p> <p>This technique applies to all technologies that present live audio-only information.</p> </div> </section> <section id="description"><h2>Description</h2> <p>The objective of this technique is to use a real-time caption service to provide a text version of live audio content. Such services use a trained human operator who listens in to what is being said and uses a special keyboard to enter the text with only a small delay. They are able to capture a live event with a high degree of fidelity, and also to insert notes on any non spoken audio which is essential to understanding the event. The viewport containing the caption text is available on the same Web page as the live audio content.</p> </section><section id="examples"><h2>Examples</h2> <ul> <li>An internet radio station provides a viewport on its Web page for its news services. Live news reports, especially emergency reports, are transcribed by a real-time caption service and displayed in the viewport.</li> <li>A conferencing or screen-sharing service includes a window with running real-time transcription of the verbal presentation. This is achieved by arranging ahead of time with a remote relay audio-teleconference captioning service. The online web conferencing or screen-sharing service needs to be designed with this possible usage in mind because using a separate window for the live text would be a significant usability barrier.</li> <li>A recurring audio conference uses an online hand-raising utility to assist with queuing. In order to facilitate use of this product in conjunction with an on-line relay conference captioning service, the queuing utility is designed to be fully operational in a narrow viewport. For additional enhancement, a website is created to bring up both viewports within a single Web page.</li> </ul> </section><section id="resources"><h2>Related Resources</h2> <p style="margin-bottom: 1.5em;"><em><small>No endorsement implied.</small></em></p> <ul> <li> <a href="http://webaim.org/techniques/captions/realtime">Real-time Captioning</a> </li> <li> <a href="http://www.captionedtext.com/">Captioned Text</a> (provider for relay conference captioning)</li> <li> <a href="https://en.wikipedia.org/wiki/Communication_Access_Real-Time_Translation">Wikipedia entry for CART</a> (variously Computer Assisted Real-time Captioning or Communication Access Real-time Translation)</li> <li> <a href="http://www.ncra.org/">Communication Access Information Center</a> </li> <li> <p>Web conferencing products with integrated support for captioning viewport</p> <ul> <li> <a href="http://www.adobe.com/products/adobeconnect/apps/closed-captioning.html">Adobe Connect</a> </li> <li> <a href="http://captionfirst.com/">Caption First</a> </li> <li> <a href="http://sovo-tech.com/">Sovo Closed Captioning and Audio Description Services </a> </li> </ul> </li> </ul> </section> <section id="related"><h2>Related Techniques</h2><ul> <li><a href="../general/G150">G150: Providing text based alternatives for live audio-only content</a></li> <li><a href="../general/G58">G58: Placing a link to the alternative for time-based media immediately next to the non-text content</a></li> <li><a href="../general/G69">G69: Providing an alternative for time based media</a></li> </ul></section> <section id="tests"><h2>Tests</h2> <section class="procedure" id="procedure"><h3>Procedure</h3> <ol> <li>Check that the Web page contains a viewport associated with the live audio content.</li> <li>Check that the text of the live audio content appears in the viewport with less than 30 seconds delay.</li> </ol> </section> <section class="results" id="expected-results"><h3>Expected Results</h3> <ul> <li>All checks above are true.</li> </ul> </section> </section> <a class="button button-backtotop" href="#top"> <span> <svg focusable="false" aria-hidden="true" class="icon-arrow-up " viewBox="0 0 26 28"> <path d="M25.172 15.172c0 0.531-0.219 1.031-0.578 1.406l-1.172 1.172c-0.375 0.375-0.891 0.594-1.422 0.594s-1.047-0.219-1.406-0.594l-4.594-4.578v11c0 1.125-0.938 1.828-2 1.828h-2c-1.062 0-2-0.703-2-1.828v-11l-4.594 4.578c-0.359 0.375-0.875 0.594-1.406 0.594s-1.047-0.219-1.406-0.594l-1.172-1.172c-0.375-0.375-0.594-0.875-0.594-1.406s0.219-1.047 0.594-1.422l10.172-10.172c0.359-0.375 0.875-0.578 1.406-0.578s1.047 0.203 1.422 0.578l10.172 10.172c0.359 0.375 0.578 0.891 0.578 1.422z"></path> </svg> Back to Top </span> </a> </main> <aside class="box box-icon box-space-above" id="helpimprove" style="grid-column: 2 / 8; grid-row: 3"> <header class="box-h box-h-icon box-h-space-above box-h-icon"> <svg focusable="false" aria-hidden="true" class="icon-comments" viewBox="0 0 28 28"> <path d="M22 12c0 4.422-4.922 8-11 8-0.953 0-1.875-0.094-2.75-0.25-1.297 0.922-2.766 1.594-4.344 2-0.422 0.109-0.875 0.187-1.344 0.25h-0.047c-0.234 0-0.453-0.187-0.5-0.453v0c-0.063-0.297 0.141-0.484 0.313-0.688 0.609-0.688 1.297-1.297 1.828-2.594-2.531-1.469-4.156-3.734-4.156-6.266 0-4.422 4.922-8 11-8s11 3.578 11 8zM28 16c0 2.547-1.625 4.797-4.156 6.266 0.531 1.297 1.219 1.906 1.828 2.594 0.172 0.203 0.375 0.391 0.313 0.688v0c-0.063 0.281-0.297 0.484-0.547 0.453-0.469-0.063-0.922-0.141-1.344-0.25-1.578-0.406-3.047-1.078-4.344-2-0.875 0.156-1.797 0.25-2.75 0.25-2.828 0-5.422-0.781-7.375-2.063 0.453 0.031 0.922 0.063 1.375 0.063 3.359 0 6.531-0.969 8.953-2.719 2.609-1.906 4.047-4.484 4.047-7.281 0-0.812-0.125-1.609-0.359-2.375 2.641 1.453 4.359 3.766 4.359 6.375z"></path> </svg> <h2>Help improve this page</h2> </header> <div class="box-i"> <p>Please share your ideas, suggestions, or comments via e-mail to the publicly-archived list <a href="mailto:public-agwg-comments@w3.org?subject=%5BUnderstanding%20and%20Techniques%20Feedback%5D">public-agwg-comments@w3.org</a> or via GitHub</p> <div class="button-group"> <a href="mailto:public-agwg-comments@w3.org?subject=%5BUnderstanding%20and%20Techniques%20Feedback%5D" class="button"><span>E-mail</span></a> <a href="https://github.com/w3c/wcag/issues/" class="button"><span>Fork & Edit on GitHub</span></a> <a href="https://github.com/w3c/wcag/issues/new" class="button"><span>New GitHub Issue</span></a> </div> </div> </aside> </div> <footer id="wai-site-footer" class="page-footer default-grid" aria-label="Page"> <div class="inner" style="grid-column: 2 / 8"> <p><strong>Date:</strong> Updated 02 April 2024.</p> <p><strong>Developed by</strong> <a href="https://www.w3.org/groups/wg/ag/participants">Accessibility Guidelines Working Group (AG WG) Participants</a> (Co-Chairs: Alastair Campbell, Charles Adams, Rachael Bradley Montgomery. 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