[whatwg] Proposal for an addition to the authoring guidance regarding the alt attribute
derernst at gmx.ch
Tue Aug 3 03:55:06 PDT 2010
Section 22.214.171.124.9 describes how alternative text for content images
should be written:
Then, there is a general guideline about writing alternative texts in
section 126.96.36.199.12: "A corollary to this is that the alt attribute's
value should never contain text that could be considered the image's
caption, title, or legend. It is supposed to contain replacement text
that could be used by users instead of the image; it is not meant to
supplement the image. The title attribute can be used for supplemental
IMO the wording of 188.8.131.52.9 is somehow contradictive to the general
guidance in two cases:
1. The image is the information itself, it does not convey any
information beyond it's visuals. This is a very common case, for example
in photo galleries. Unlike the examples given under "The general case"
(where lack of the image is lack of information), the images in a
wedding photo gallery cannot be described in a way that matches
184.108.40.206.12 and provides any useful information for e.g. a blind user.
The information "Me, Gary, and his parents eating the cake" is rather
useful for those who actually see the image, and should go to the
caption, as correctly stated in 220.127.116.11.12.
2. The image illustrates what is discussed in the surrounding text, or
has a caption describing it. Inserting alt text would actually duplicate
the information, but not convey anything useful for those who don't see
the image. IMO alternative text should be omitted in this case (as e.g.
Wikipedia does: http://en.wikipedia.org/wiki/Squirrel - the alt
attribute values of all content images are empty).
So I propose to:
- Explicitly treat these two cases in 18.104.22.168.9, requiring to insert no
alt text there
- In the part "Images whose contents are not known", remove the word
"unfortunate" at the beginning ("In some cases"), and the first note.
(Apparently, the W3C itself is not so sure about alt text in content
images; http://www.w3.org/Consortium/mission illustrates this: There is
a picture of Tim Berners-Lee, with no direct reference in the text. It
does not seem to be decorative, as according to 22.214.171.124.6 the alt
attribute should be empty in this case; but the alt text says: "Tim
Berners-Lee speaking at W3C10", which is not an information conveyed by
the image itself if you don't know how Tim Berners-Lee looks like. Thus,
according to 126.96.36.199.9, this information should be displayed in a
caption, and the alt attribute should say something like "A male speaker
in front of a display containing the text 'W3C10 Tenth Anniversary' and
some sponsor logos" - which is of course stupid. The empty string would
IMO be the appropriate value for the alt attribute here.)
More information about the whatwg