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Accessibility Guidelines "Silver"
https://w3c.github.io/silver/
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"Image accessible name is descriptive" is a bad title #687

Closed johnfoliot closed 10 months ago

johnfoliot commented 1 year ago

Re: https://www.w3.org/WAI/standards-guidelines/act/rules/qt1vmo/proposed/

EDITORIAL PROPOSAL: Change the title to Image accessible name is a functional equivalent


This document is currently titled Image accessible name is descriptive, which is already off to a bad start: image alternative text(s) are intended to be a functional equivalent to the image (aka accessible NAME), and not just a "description" (aka accessible DESCRIPTION).

For example, when you see the following code pattern:

<a href="foo.html"> <img src="printer_icon.png"> </a>

...the alternative text is not (or rather should not be) "black and white printer icon" (which is a literal description of the image), but instead "Print" (or better, "Print this page"), because that is the functional intent of that image.

The current draft also shows the following:

<html lang="en">
    <img src="/test-assets/shared/w3c-logo.png" alt="W3C logo" />
</html>

Which isn't always wrong, but would certainly be wrong if used like this:

<html lang="en">
    <a href="https://w3.org"><img src="/test-assets/shared/w3c-logo.png" alt="W3C logo" /></a>
</html>

...because the link does not take the user to "W3C logo" (a thing, but not a destination). In that case the text alternative example should be:

<html lang="en">
    <a href="https://w3.org"><img src="/test-assets/shared/w3c-logo.png" alt="W3C Home" /></a> (or similar)
</html>

Likewise, this would also be wrong:

Incorrect: <img src="piechart.png" alt="A circular pie chart with 12 sections, each section is a different color and labeled January, February, March, April, May, etc." /> [that is, per the document, a "description" of the image]

Correct: <img src="piechart.png" alt="Fiscal earnings for calendar 2022" /> [accessible NAME]

<details> 
  <summary> Chart Data</summary>  [accessible DESCRIPTION]
  <p>The chart shows monthly earnings for each of the 12 months:</p>
  <ul>
    <li>January: $22,000</li>
    <li>February: $18,700</li>
    <li>March: $24,100</li>
    ...
  </ul>
</details>

As such, much of the content on that resource page that states "...describes the image" (or a variant of that) is incorrect: it's NOT a description, it's a text string that serves the equivalent function of the image (i.e., an alternative) and provides an accessible name to the image.

WilcoFiers commented 10 months ago

@johnfoliot I've copied this issue to the ACT Rules repository, which is where the source of this lives. We'll pick up the work there.