Guide to Guideline 1.2 Level 1 Success Criterion 1

Intent of this success criterion

The intent of this success criterion is to enable people who are deaf or hard of hearing to watch multimedia presentations. Captions provide the part of the content available via the audio track. Captions not only include dialog, but identify who is speaking and notate sound effects and other significant audio.

Techniques for addressing 1.2 L1 SC1

The following combinations of techniques are deemed to be sufficient by the WCAG Working Group for meeting success criterion 1.2 L1 SC1.

Use a technology-specific technique to create a caption for the multimedia content AND @@do we need conditions or discussion on how to write good captions?

Technology-Specific Techniques for 1.2 L1 SC1

Captions in SMIL 1.0

Provide captions as text stream elements where the system-captions test attribute has the value on

Video with caption area underneath.

<smil xmlns="http://www.w3.org/TR/REC-smil">

<head>
   <layout>
     <root-layout background-color="black" height="266" width="320"/>
     <region id="video" background-color="black" top="26" left="0" height="144" width="320"/>
     <region id="captions" background-color="black" top="186" height="80" left="0" width="320"/>
   </layout>
</head>

<body>	
   <par>
     <textstream src="captions.rt" region="captions" system-captions="on" title="captions"/>
     <video src="movie.rm" begin="00:00.0" region="video" title="video"/>
   </par>	  
</body>

</smil>

Captions in SMIL 2.0

Provide captions as text streams where the systemCaptions test attribute has the value on

Video with captions.

<smil xmlns="//www.w3.org/2001/SMIL20/Language">

<head>
   <layout>
     <root-layout backgroundColor="black" height="266" width="320"/>
     <region id="video" backgroundColor="black" top="26" left="0" height="144" width="320"/>
     <region id="captions" backgroundColor="black" top="186" height="80" left="0" width="320"/>
   </layout>
</head>

<body>	
  <par>
    <textstream src="captions.rt" region="captions" systemCaptions="on" title="captions"/>
    <video src="movie.rm" region="video" title="video"/>
  </par>
</body>

</smil>

Common Failures Identified by the Working Group

The following are common mistakes which are considered failures of this success criterion by the working group.

@@

Optional Techniques (Advisory) for 1.2 L1 SC1

Although not required for conformance, the following additional techniques should be considered in order to make content more accessible. Not all techniques can be used or would be effective in all situations.

Additional SMIL 1.0 Techniques (Advisory)

Provide captions in multiple languages by providing text streams with system-captions=on and the system-language attribute set to the language name of the language used in that text stream.