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Re: Question about image in the alt attribute

for

From: Jonathan Metz
Date: Aug 1, 2014 1:21PM

On 8/1/14, 2:01 PM, "Jukka K. Korpela" < <EMAIL REMOVED> > wrote:


>What? That sounds hopelessly abstract.

I'm not sure I comprehend your statement. If you didn't understand me,
please just say so. I was saying a supporting document expanding something
a spec document states does not imply that that the supporting document is
preferring technology over users.

>
>>For one thing, Jukka only linked to it's relationship with the <src> tag,
>>and seems to be hung up on the phrase "...when not available".
>
>No, I did not mention the <src> tag

The link you originally provided…

>>"alt - Replacement text for use when images are not available"
>>http://www.w3.org/TR/html5/embedded-content-0.html#attr-img-alt

…references the src attribute:

"The image given by the src attributes is the embedded content; the value
of the alt attribute provides equivalent content for those who cannot
process images or who have image loading disabled."

Then immediately following that is:

"The requirements on the alt
<http://www.w3.org/TR/html5/embedded-content-0.html#attr-img-alt>;
attribute's value are described in the next section
<http://www.w3.org/TR/html5/embedded-content-0.html#alt>;."


>(there is no such tag),


::rolling eyes, shaking head::




>and yes, I
>am advocating the use of an alt attribute for the purpose it was
>designed for and has been defined in HTML specifications.


But that is not where you were linking to. The definition is found here:
<http://www.w3.org/TR/html5/embedded-content-0.html#alt>;



>
>>The requirements for the attribute is actually explained under 4.7.1.1,
>>which
>>references WCAG: alt attributes "are a primary way of making visual
>>information accessible, because they can be rendered through any sensory
>>modality (for example, visual, auditory or tactile) to match the needs of
>>the user."
>
>This simply means that the alt attribute is to be rendered *instead of*
>the image. The phrase "making visual information accessible" is poorly
>formulated, since alt attributes are not meant to make blind people see.


I guess if WCAG were written for the sole purpose of helping blind people
access content, that comment might make more sense to me. Yet WCAG is not
implying that "making visual information accessible" means "providing the
gift of sight". Instead it is implying more than one way of providing
information.


>Instead, they are the way to make *some* information available to people
>who do not see the image.


Yeah, true… That would be ONE reason for using alternate text. But there
are other reasons too:

4.7.1.1.1 Examples of scenarios where users benefit from text alternatives
for images

* They have a very slow connection and are browsing with images disabled.
* They have a vision impairment and use text to speech software.
* They have a cognitive impairment and use text to speech software.
* They are using a text-only browser.
* They are listening to the page being read out by a voice Web browser.
* They have images disabled to save on download costs.
* They have problems loading images or the source of an image is wrong.

Clearly, the specification states multiple benefits of using text
alternatives.



>Realistically speaking, when the image is a
>photo, for example, the alt text *cannot* correspond to the visual
>information very well.


I don't think I understand you here. Are you saying that if a photo is
included, there is no way to describe what is going on in the photo?



>Authors should do their best, but they should not
>be required to do more.


"Doing their best" is a really vague concept, and runs a risk of relying
on a person's level of laziness.

If authors are having a difficult time understanding what content makes
for good alt text, there are plenty of techniques for text alternatives.
Here's an authoritative example:

http://www.w3.org/WAI/WCAG20/quickref/#text-equiv



>The alt attribute is most useful when there is a simple text replacement
>for an image, so obvious that anyone who sees the image and understands
>its context can write the text in a second.

I happen to disagree. In my opinion, alt text is the most useful when it
clearly describes non-text in as succinctly as possible. If that happens
to mean a longer description, then so be it.

>Purely decorative images and
>text as images are the most obvious cases. This is where the alt
>attribute does its job well when written to act as a replacement, not a
>description (say, "item" or "bullet", not "red fancy bullet with
>blinking eyes").

Wait. What? Why would you provide information for purely inconsequential
items?

>
>>>>"Pure decoration." Too ambiguous a term. Undefined. Nearly everything
>>>>that
>>>>isn't text could end up classified as "pure decoration."
>>
>>Explained a little further down the page
>><http://www.w3.org/TR/WCAG20/#puredecdef>; as a definition: "Pure
>>decoration: serving only an aesthetic purpose, providing no information,
>>and having no functionality. Note: Text is only purely decorative if the
>>words can be rearranged or substituted without changing their purpose.
>>Example: The cover page of a dictionary has random words in very light
>>text in the background."
>
>That's a manifestly poor example. Those random words are excerpts from
>the dictionary. When I look at them, I can see that it is an English
>dictionary, or a French dictionary, or a Greek dictionary, or whatever
>it might be. It's far from being "pure decoration".


Sorry, I didn't write the example: it's from WCAG. Still, if you came
across a subtle background of a seashell pattern on a web site about coral
plant life, would you really want to be notified that the designer used a
repeating clip art graphic?


>But it's an image for which alt="" is adequate, on the simple grounds
>that this is the only no-nonsense approach. There is no way (or at least
>I cannot see a way) to present the same information in a non-visual way
>in a similarly non-disruptive manner.


So… You're agreeing that this was a good example then? Excuse me for
sounding obtuse, but are we just arguing now?


>If you make a speech browser speak
>those words, or a Braille device present them, or a text-only browser
>display them, you would be giving the same information, but in a wrong
>way, disturbing the user rather than helping him.


I completely agree with you here.

There are often times when I come across a web page and I see something
that is artsy. These things are generally ignored. Often times I will go
to a very technical document and start reading it. A lot of times, I have
difficulty understanding what they are talking about, and sometimes an
image will be helpful to convey the information. If I encounter an image
with it that doesn't make sense to the rest of the content, I'll inspect
the element and see if there is alternate description. If I see that the
content is basically describing what is going on in the photo but has
nothing to do with what I'm reading about, I'm still as lost as I was
before, only several minutes later and now also distracted about why that
image was included as a reference.

However, if I come across content I don't understand and inspect an
accompanied photo to learn it doesn't have alternate text, I assume that
it's just filler. I'm still lost, but now I can focus on trying to
understand the information in the content rather than how the content
relates to a stock photo.

Jon




On 8/1/14, 2:01 PM, "Jukka K. Korpela" < <EMAIL REMOVED> > wrote:

>2014-08-01 20:06, Jonathan Metz wrote:
>
>> In my opinion, there is no correlation between a specification
>>addressing
>> the purpose of an attribute and a supporting document's extrapolation of
>> accessibility benefits for providing that attribute that would infer a
>> preference for user agents.
>
>What? That sounds hopelessly abstract.
>
>> For one thing, Jukka only linked to it's relationship with the <src>
>>tag,
>> and seems to be hung up on the phrase "...when not available".
>
>No, I did not mention the <src> tag (there is no such tag), and yes, I
>am advocating the use of an alt attribute for the purpose it was
>designed for and has been defined in HTML specifications.
>
>> The requirements for the attribute is actually explained under 4.7.1.1,
>>which
>> references WCAG: alt attributes "are a primary way of making visual
>> information accessible, because they can be rendered through any sensory
>> modality (for example, visual, auditory or tactile) to match the needs
>>of
>> the user."
>
>This simply means that the alt attribute is to be rendered *instead of*
>the image. The phrase "making visual information accessible" is poorly
>formulated, since alt attributes are not meant to make blind people see.
>Instead, they are the way to make *some* information available to people
>who do not see the image. That information is to be written by the
>author, and it *should* correspond, as far as possible, the visual
>information in the image. Realistically speaking, when the image is a
>photo, for example, the alt text *cannot* correspond to the visual
>information very well. Authors should do their best, but they should not
>be required to do more.
>
>The alt attribute is most useful when there is a simple text replacement
>for an image, so obvious that anyone who sees the image and understands
>its context can write the text in a second. Purely decorative images and
>text as images are the most obvious cases. This is where the alt
>attribute does its job well when written to act as a replacement, not a
>description (say, "item" or "bullet", not "red fancy bullet with
>blinking eyes").
>
>>>> "Pure decoration." Too ambiguous a term. Undefined. Nearly everything
>>>> that
>>>> isn't text could end up classified as "pure decoration."
>>
>> Explained a little further down the page
>> <http://www.w3.org/TR/WCAG20/#puredecdef>; as a definition: "Pure
>> decoration: serving only an aesthetic purpose, providing no information,
>> and having no functionality. Note: Text is only purely decorative if the
>> words can be rearranged or substituted without changing their purpose.
>> Example: The cover page of a dictionary has random words in very light
>> text in the background."
>
>That's a manifestly poor example. Those random words are excerpts from
>the dictionary. When I look at them, I can see that it is an English
>dictionary, or a French dictionary, or a Greek dictionary, or whatever
>it might be. It's far from being "pure decoration".
>
>But it's an image for which alt="" is adequate, on the simple grounds
>that this is the only no-nonsense approach. There is no way (or at least
>I cannot see a way) to present the same information in a non-visual way
>in a similarly non-disruptive manner. If you make a speech browser speak
>those words, or a Braille device present them, or a text-only browser
>display them, you would be giving the same information, but in a wrong
>way, disturbing the user rather than helping him.
>
>It would be a different matter if the cover page did not contain a
>normal title of the dictionary at all, just those random words. Then the
>information conveyed by those words, in a rather implicit way, would be
>too important for the context to be simply omitted. Then you should find
>out what the dictionary really is about and say that in the alt
>attribute, e.g. alt="An English dictionary of obscene words" or alt="A
>French dictionary of cooking terms". If you cannot do that, and cannot
>get help on it, the least of evils would be to write an alt attribute
>that contains the words or some subset of them.
>
>Yucca
>
>
>>>