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Does WCAG allow AT to be used to meet the SC?

From: Bailey, Bruce <Bailey@Access-Board.gov>
Date: Fri, 22 Jun 2012 00:01:52 +0000
To: Gregg Vanderheiden <gv@trace.wisc.edu>, GLWAI Guidelines WG org <w3c-wai-gl@w3.org>
Message-ID: <C18AC41C570F214AAD320947DF8D16CE6DF44593@BLUPRD0810MB354.namprd08.prod.outlook.com>
On the call earlier I asserted that the qualifier in 1.4.4 Resize Text of “without assistive technology” is superfluous.  By way of demonstration, I have inserted the phrase in several SC below.  I think you will agree that in all cases, the phrase is pointless, and does not change the intent or meaning.  On the other hand, allowing AT to be considered renders many SC moot.

Proof by demonstration, Part the First (adding the phrase makes no difference):

1.2.2 Captions (Prerecorded):  Captions are provided without assistive technology for all prerecorded audio content in synchronized media, except when the media is a media alternative for text and is clearly labeled as such.  (Level A)

1.2.6 Sign Language (Prerecorded):  Sign language interpretation is provided without assistive technology for all prerecorded audio content in synchronized media.  (Level AAA) 

1.4.3 Contrast (Minimum):  The visual presentation of text and images of text has a contrast ratio of at least 4.5:1 without assistive technology, except for the following:…  (Level AA)

1.4.4 Resize text:  Except for captions and images of text, text can be resized without assistive technology up to 200 percent without loss of content or functionality. (Level AA) 

1.4.6 Contrast (Enhanced):  The visual presentation of text and images of text has a contrast ratio of at least 7:1 without assistive technology, except for the following:  (Level AAA)

1.4.8 Visual Presentation:  For the visual presentation of blocks of text, a mechanism is available to achieve the following without assistive technology:…  (Level AAA) 

2.1.1 Keyboard:  All functionality of the content is operable through a keyboard interface without assistive technology and without requiring specific timings for individual keystrokes, except where the underlying function requires input that depends on the path of the user's movement and not just the endpoints.  (Level A)

2.1.3 Keyboard (No Exception):  All functionality of the content is operable through a keyboard interface without assistive technology and without requiring specific timings for individual keystrokes.  (Level AAA) 

2.2.2 Pause, Stop, Hide:  For moving, blinking, scrolling, or auto-updating information, all of the following are true without assistive technology:…  (Level A) 

2.4.7 Focus Visible:  Any keyboard operable user interface has a mode of operation where the keyboard focus indicator is visible without assistive technology.  (Level AA)


Proof by demonstration, Part the Second (reductio ad absurdum, with appropriate assistive technology, all the following are satisfied, so they are rendered moot, and can be disregarded):

1.2.2 Captions (Prerecorded):  Captions are provided for all prerecorded audio content in synchronized media, except when the media is a media alternative for text and is clearly labeled as such.  (Level A)

This one is a stretch at present since the AT is not there yet, but it is easy to image technology like Google machine-generated automatic captions (but that works for media besides YouTube) being a paid application.

1.2.6 Sign Language (Prerecorded):  Sign language interpretation is provided for all prerecorded audio content in synchronized media.  (Level AAA) 

Since an author can assume people who need it have AT like Signing Avatar from VCom3D, this SC can be assumed to be satisfied.

1.4.3 Contrast (Minimum):  The visual presentation of text and images of text has a contrast ratio of at least 4.5:1, except for the following:…  (Level AA)

Since an author can assume people who need it have AT like ZoomText or MAGic, this SC can be assumed to be satisfied.

1.4.4 Resize text:  Except for captions and images of text, text can be resized up to 200 percent without loss of content or functionality.  (Level AA) 

Since an author can assume people who need it have AT like ZoomText or MAGic, this SC can be assumed to be satisfied.

1.4.6 Contrast (Enhanced):  The visual presentation of text and images of text has a contrast ratio of at least 7:1, except for the following:  (Level AAA)

Since an author can assume people who need it have AT like ZoomText or MAGic, this SC can be assumed to be satisfied.

1.4.8 Visual Presentation:  For the visual presentation of blocks of text, a mechanism is available to achieve the following:…  (Level AAA) 

Since AT productsT like ZoomText or MAGic provide such features for most content, this SC can be assumed to be satisfied by authors.

2.1.1 Keyboard:  All functionality of the content is operable through a keyboard interface without requiring specific timings for individual keystrokes, except where the underlying function requires input that depends on the path of the user's movement and not just the endpoints.  (Level A)

Since there are numerous AT products that emulate mouse functions through the keyboard or even switches, this SC can be assumed by authors to be sufficiently addressed.

2.1.3 Keyboard (No Exception):  All functionality of the content is operable through a keyboard interface without requiring specific timings for individual keystrokes.  (Level AAA)

Since there are numerous AT products that emulate mouse functions through the keyboard or even switches, this SC can be assumed by authors to be sufficiently addressed.

2.2.2 Pause, Stop, Hide:  For moving, blinking, scrolling, or auto-updating information, all of the following are true:…  (Level A)

Since there are numerous products for slowing down computers (both for old games and as AT), this SC can be assumed to be addressed by authors.

2.4.7 Focus Visible:  Any keyboard operable user interface has a mode of operation where the keyboard focus indicator is visible.  (Level AA)

Since AT products like ZoomText and MAGic provide enhanced cursors, this SC can be assumed to be satisfied by authors.
Received on Friday, 22 June 2012 00:02:48 GMT

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