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HTML and XHTML Techniques - Providing Text Alternatives for Functional Images

From: WCAG 2.0 Techniques Submission Form <nobody@w3.org>
Date: Wed, 4 Jun 2008 17:06:06 +0000 (UTC)
To: public-wcag2-techs@w3.org
Message-Id: <20080604170606.8ACB51AB5A4@spiderpig.w3.org>


Submitter's Name: Laura Carlson
Submitter's Email: laura.lee.carlson@gmail.com

Technique ID: UNKNOWN
Short Name: Providing Text Alternatives for Functional Images
Technique Category: HTML and XHTML Techniques
Guideline Reference: text-equiv
Success Criterion Reference: UNKNOWN

Applicability:
Applies to HTML

UA Issues:
None known

Description:
The objective of this technique is explain and demonstrate how to markup functional images. Functional images are images that allow the user to &#039;do&#039; things. They provide functionality. Activating or selecting a functional image causes something to happen, such as activating a link that causes a resource to be retrieved.



To provide the same functionality to the user, emphasize the action performed by the image or the link purpose. For instance, if a search button is a magnifying glass or binoculars, appropriate alt text could be &quot;search&quot; or &quot;find&quot;; not &quot;magnifying glass&quot;, &quot;binoculars&quot; or &quot;button&quot;. For navigation images, use the destination of the link as alt text. &quot;Previous page&quot; or &quot;Next page&quot; would be appropriate alt text for navigation images; not &quot;picture of an arrow&quot;. By default, on receiving focus, a screen reader will announce to the user that it is link. So for navigation images, it is unnecessary to say &quot;Link to previous page&quot;. &quot;Previous page&quot; will suffice. If a redundant text link of a navigation image is provided, the value of the alt attribute of the image can be null (alt=&quot;&quot;).



Examples

* Navigation Links

* Buttons 

Example 1 Head: Navigation link
Example 1 Description:
&lt;a href=&quot;page1.html&quot;&gt;&lt;img src=&quot;leftarrow.png&quot; alt=&quot;Previous page&quot;&gt;&lt;/a&gt;

Example 2 Head: Navigation link with text content.
Example 2 Description:
&lt;a href=&quot;page1.html&quot;&gt;&lt;img src=&quot;leftarrow.png&quot; alt=&quot;&quot;&gt;Previous page&lt;/a&gt;

Resource 1 Title: Web Design References: Accessibility
Resource 1 URI: http://www.d.umn.edu/itss/support/Training/Online/webdesign/accessibility.html#alt

Related Techniques:
H36
H37

Test Procedure:
1. remove, hide, or mask the non-text content

2. replace it with the text alternative

3. Check that nothing is lost (the purpose of the non-text content is met by the text alternative)

4. If the non-text content contains words that are important to understanding the content, the words are included in the text alternative.

Expected Result:
Check #3 is true. If the non-text content contains words that are important to understanding the content, check #4 is also true.

Additional Notes:
This technique is part of the HTMLWG&#039;s Action 54: First Draft

http://esw.w3.org/topic/HTML/Action54AltAttribute



If it is accepted by WCAG we hope to remove it from our document as stated in the second draft

http://esw.w3.org/topic/HTML/Action54AltAttributeSecondDraft#head-f0bf2ebf9f3e1fa190974101c6b70700ff176772



The Action 54 first draft provides much non-normative guidance in the application of the ALT attribute, which may not be appropriate for inclusion in a markup language specification, and which moreover could be seen as usurping the role of WCAG 2.0 and its techniques documents. A format specification is not a tutorial. It would be very helpful if the Techniques for WCAG 2.0. could incorporate this information or a variation of it. Then the HTML5 spec could link to it. As PF has said, &quot;WCAG WG is chartered to set Accessibility guidelines and HTML WG is not&quot;.

http://lists.w3.org/Archives/Public/public-html/2008Feb/0082.html



Thank you,



The HTMLWG Action 54 Team:

Steven Faulkner

Joshue O Connor

Laura Carlson



Peer reviewers:

Gez Lemon

Gregory Rosmaita

No resource 2 title submitted!
No resource 2 URI submitted!
No test file 1 was submitted!
No test file 1 pass/fail was submitted!
No test file 2 was submitted!
No test file 2 pass/fail was submitted!


------------------------------------------------

<technique id="UNKNOWN">
<short-name>Providing Text Alternatives for Functional Images</short-name>
<applies-to>
<guideline idref="text-equiv" />
<success-criterion idref="UNKNOWN" />
</applies-to>

<applicability>
Applies to HTML
</applicability>
<ua_issues>
None known
</ua_issues>
<description>
The objective of this technique is explain and demonstrate how to markup functional images. Functional images are images that allow the user to &#039;do&#039; things. They provide functionality. Activating or selecting a functional image causes something to happen, such as activating a link that causes a resource to be retrieved.



To provide the same functionality to the user, emphasize the action performed by the image or the link purpose. For instance, if a search button is a magnifying glass or binoculars, appropriate alt text could be &quot;search&quot; or &quot;find&quot;; not &quot;magnifying glass&quot;, &quot;binoculars&quot; or &quot;button&quot;. For navigation images, use the destination of the link as alt text. &quot;Previous page&quot; or &quot;Next page&quot; would be appropriate alt text for navigation images; not &quot;picture of an arrow&quot;. By default, on receiving focus, a screen reader will announce to the user that it is link. So for navigation images, it is unnecessary to say &quot;Link to previous page&quot;. &quot;Previous page&quot; will suffice. If a redundant text link of a navigation image is provided, the value of the alt attribute of the image can be null (alt=&quot;&quot;).



Examples

* Navigation Links

* Buttons 
</description>

<examples>
<ex_head_1>
Navigation link
</ex_head_1>
<ex_desc_1>
<a href=&quot;page1.html&quot;><img src=&quot;leftarrow.png&quot; alt=&quot;Previous page&quot;></a>
</ex_desc_1>
<ex_head_2>
Navigation link with text content.
</ex_head_2>
<ex_desc_2>
<a href=&quot;page1.html&quot;><img src=&quot;leftarrow.png&quot; alt=&quot;&quot;>Previous page</a>
</ex_desc_2>
</examples>

<resources>
<resources_title1>
Web Design References: Accessibility
</resources_title1>
<resource_uri1>
http://www.d.umn.edu/itss/support/Training/Online/webdesign/accessibility.html#alt
</resource_uri1>
<resources_title2>

</resources_title2>
<resource_uri2>

</resource_uri2>
</resources>

<related_techniques>
<related_technique>
H36
</related_technique>
<related_technique>
H37
</related_technique>
</related_techniques>

<tests>
<procedure>
1. remove, hide, or mask the non-text content

2. replace it with the text alternative

3. Check that nothing is lost (the purpose of the non-text content is met by the text alternative)

4. If the non-text content contains words that are important to understanding the content, the words are included in the text alternative.
</procedure>
<expected_result>
Check #3 is true. If the non-text content contains words that are important to understanding the content, check #4 is also true.
</expected_result>
<test_file_1>

</test_file_1>
<pass_fail_1>

</pass_fail_1>
<test_file_2>

</test_file_2>
<pass_fail_2>

</pass_fail_2>
</tests>

</technique>

Additional Notes:

This technique is part of the HTMLWG&#039;s Action 54: First Draft

http://esw.w3.org/topic/HTML/Action54AltAttribute



If it is accepted by WCAG we hope to remove it from our document as stated in the second draft

http://esw.w3.org/topic/HTML/Action54AltAttributeSecondDraft#head-f0bf2ebf9f3e1fa190974101c6b70700ff176772



The Action 54 first draft provides much non-normative guidance in the application of the ALT attribute, which may not be appropriate for inclusion in a markup language specification, and which moreover could be seen as usurping the role of WCAG 2.0 and its techniques documents. A format specification is not a tutorial. It would be very helpful if the Techniques for WCAG 2.0. could incorporate this information or a variation of it. Then the HTML5 spec could link to it. As PF has said, &quot;WCAG WG is chartered to set Accessibility guidelines and HTML WG is not&quot;.

http://lists.w3.org/Archives/Public/public-html/2008Feb/0082.html



Thank you,



The HTMLWG Action 54 Team:

Steven Faulkner

Joshue O Connor

Laura Carlson



Peer reviewers:

Gez Lemon

Gregory Rosmaita
Received on Wednesday, 4 June 2008 17:06:48 GMT

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