RGAA 3.0 - Rule 1.5.1

Summary

This test consists in detecting images associated with an image used as a CAPTCHA.

Business description

Criterion

1.5

Test

1.5.1

Description

Does each image (img, area, object, embed, svg, canvas tags) used as CAPTCHA meet one of the following conditions? Another non graphic form of CAPTCHA is available, at least

Level

A

Technical description

Scope

Page

Decision level

Semi-Decidable

Algorithm

Selection

Set1

All the <img> tags of the page not within a link (css selector : img:not(a img))

Set2

All the elements of Set1 identified as a CAPTCHA (see Notes for details about CAPTCHA characterisation).

Set3

All the <object> tags with a "type" attribute that starts with “image/…”, not within a link (css selector : object[type^=image]:not(a object))

Set4

All the elements of Set2 identified as a CAPTCHA (see Notes for details about CAPTCHA characterisation).

Set5

All the <embed> tags of the page not within a link and with a "type" attribute that starts with image/... (css selector : embed[type^=image]:not(a embed))

Set6

All the elements of Set5 identified as a CAPTCHA (see Notes for details about CAPTCHA characterisation).

Set7

All the <svg> tags of the page not within a link (css selector : svg:not(a svg))

Set8

All the elements of Set7 identified as a CAPTCHA (see Notes for details about CAPTCHA characterisation).

Set9

All the <canvas> tags of the page not within a link (css selector : canvas:not(a canvas))

Set10

All the elements of Set9 identified as a CAPTCHA (see Notes for details about CAPTCHA characterisation).

Set11

All the <area> tags, defined within a <map> tag whose the "id" attribute corresponds to the "usemap" attribute of an <img> tag

Set12

All the elements of Set11 identified as a CAPTCHA (see Notes for details about CAPTCHA characterisation).

Process

Test1

For each element of Set2, Set4, Set6, Set8, Set10 and Set12, raise a MessageA

MessageA
  • code : CheckCaptchaAlternativeAccess
  • status: Pre-Qualified
  • parameter : tag name, snippet
  • present in source : yes

Analysis

Not Applicable

No <img>, <area>, <object> with a "type" attribute equals to “image”, <embed> with a type attribute equals to image, <canvas> or <svg> identified as a CAPTCHA has been found on the page (Set2 AND Set4 AND Set6 AND Set8 AND Set10 AND Set12 are empty)

Pre-qualified

At least one <img>, <area>, <object> with a "type" attribute equals to “image”, <embed> with a type attribute equals to image, <canvas> or <svg> identified as a CAPTCHA has been found on the page (Set2 OR Set4 OR Set6 OR Set8 OR Set10 OR Set12 is not empty)

Notes

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

TestCases

TestCases files for rule 1.5.1