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.
Applies whenever SMIL 1.0 player is available
This technique relates to:
The objective of this technique is to provide a way for people who are deaf or otherwise have trouble hearing the dialogue in audio visual material to be able to view the material. With this technique all of the dialogue and important sounds are available in a sign-language interpretation video that is displayed in a caption area.
With SMIL 1.0, separate regions can be defined for the two videos. The two video playbacks are synchronized, with the content video displayed in one region of the screen, while the corresponding sign-language interpretation video is displayed in another region.
Example Code:
<?xml version="1.0" encoding="UTF-8"?>
<smil xmlns:qt="http://www.apple.com/quicktime/resources/smilextensions"
xmlns="http://www.w3.org/TR/REC-smil" qt:time-slider="true">
<head>
<layout>
<root-layout width="320" height="300" background-color="black"/>
<region top="0" width="320" height="240" left="0" background-color="black"
id="videoregion"/>
<region top="240" width="320" height="60" left="0" background-color="black"
id="signingregion"/>
</layout>
</head>
<body>
<par>
<video dur="0:01:20.00" region="videoregion" src="salesdemo.mov"
alt="Sales Demo"/>
<video dur="0:01:20.00" region="signingregion" system-captions="on"
src="salesdemo_si.mov" alt="Sales Demo Sign Language Interpretation"/>
</par>
</body>
</smil>Example Code:
<?xml version="1.0" encoding="UTF-8"?>
<smil xmlns="http://www.w3.org/TR/REC-smil">
<head>
<layout>
<root-layout background-color="black" height="310" width="330"/>
<region top="0" width="320" height="240" left="0" background-color="black"
id="videoregion"/>
<region top="240" width="320" height="60" left="0" background-color="black"
id="signingregion"/>
</layout>
</head>
<body>
<par>
<video dur="0:01:20.00" region="videoregion" src="salesdemo.mov"
alt="Sales Demo"/>
<video dur="0:01:20.00" region="signingregion" system-captions="on"
src="salesdemo_si.mov" alt="Sales Demo Sign Language Interpretation"/>
</par>
</body>
</smil> The example shows a <par> segment
containing two <video> tags. The
system-captions attribute indicates that the sign language video
should be displayed when the user's player setting for captions
indicates the preference for captions to be displayed. The
<layout> section defines the regions
used for the main video and the sign language interpretation video.
Resources are for information purposes only, no endorsement implied.
Enable control in content or player to turn on sign language interpretation (unless it is always shown)
Play file with sign-language interpretation
Check whether sign language interpretation is displayed
#3 is 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.