Re: [a11y] Requiring alt Re: fear of "invisible metadata"

On 6/21/07, Charles McCathieNevile <> wrote:
> On Thu, 21 Jun 2007 18:31:53 +0200, Laura Carlson
> <> wrote:

> > ALT should be required. The single most important thing a person can
> > do to make a web page accessible
> *to blind people* - which is a small fraction of people with disabilities.

Yes, of course. Thanks for bringing that up. Others include, but are
not  limited to :

People with Visual Impairments (not only blind - unable to see visual

* Color deficiency
 - Euteranopia - red-green deficiency
 - Protanopia - red deficiency
 - Tritanopia - blue/yellow deficit
 - Achromatopsia - total colour blindness
* Limited vision (can see but not well; may need large fonts or
magnifiers). Far-sightedness, and other vision impairments greatly
increase after the age of forty

2. People with Hearing Impairments

* Deaf
* Hard of hearing - cannot hear sounds reliably

3. People with Mobility Impairments

People with mobility impairments have difficulty moving one or more
parts of the body. Where web design is concerned, this usually
involves a disability involving the hands and/or arms. It can include:

* Total or partial paralysis
* Repetitive stress injuries (RSI)
* Arthritis
* Stroke
* ALS(Arterial Lateral Sclerosis; Lou Gehrig's Disease)
* Parkinson's disease
* Spinal cord injuries
* Cerebral palsy
* Loss of limbs or digits
* Low dexterity (unable to use a pointing device like a mouse and
instead must use keyboard or switch)

4. People with Learning Difficulties and/or Cognitive Impairments
Learning Difficulties

* Attention Deficit Disorder
* Dyslexia
* Low comprehension (having problems understanding content, textual or
* Low reading (having problems reading text)
* Other non-verbal learning difficulties

Cognitive Disabilities

* Loss of brain function
* Short term memory loss
* Epilepsy - may be subject to epileptic episodes
* Alzheimer's disease
* Parkinson's disease
* Multiple sclerosis

>> is to include alternative text for
>> images with alt attributes. "If there is no alt attribute at all
>> assistive technologies are not able to ignore the non-text content."
>> [1]
> Well, in practical terms, a user agent has to try and provide some help
> since this situation is a common accessibility problem, and it does it by
> more or less intelligent guesses.

The was a quote from WCAG 2:

Best Regards,

Laura L. Carlson

Received on Thursday, 21 June 2007 18:24:25 UTC