Asqatasun v4 - RGAA 3.0 - Rule 1.4.2
Summary
This test consists in detecting captcha area and thus defining the applicability of the test.
Human check will be then needed to determine whether the alternative is pertinent.
Business description
Criterion
Test
Description
Does each area (area
tag) of an image map used as a CAPTCHA or test image, with an alt
attribute, meet the following conditions?
- The content of the
alt
attribute describes the nature and purpose of the image - If present, the value of the
title
attribute matches the value of thealt
attribute
Level
A
Technical description
Scope
Page
Decision level
Semi-Decidable
Algorithm
Selection
Set1
All the <area>
tags, defined within a <map>
tag whose the "id"
attribute corresponds to the "usemap"
attribute of an <img>
tag, with a "href"
and an "alt"
attribute
Set2
All the elements of Set1 identified as a CAPTCHA (see Notes for details about CAPTCHA characterisation).
Process
Test1
For each element of Set2, raise a MessageA
MessageA : Check captcha alternative
- code : CheckCaptchaAlternative
- status: Pre-Qualified
- parameter :
"alt"
attribute,"href"
attribute, tag name, snippet - present in source : yes
Analysis
Not Applicable
The page has no <area>
tag with a "href"
and an "alt"
attribute identified as a captcha (Set2 is empty)
Pre-qualified
In all other cases
Notes
Captcha detection
An element is identified as a CAPTCHA when the "captcha" occurrence is found :
- on one attribute of the element
- or within the text of the element
- or on one attribute of one parent of the element
- or within the text of one parent of the element
- or on one attribute of a sibling of the element
- or within the text of a sibling of the element