Re: [whatwg] Proposal for an addition to the authoring guidance regarding the alt attribute
On Tue, 3 Aug 2010, Markus Ernst wrote: Section 4.8.1.1.9 describes how alternative text for content images should be written: http://www.w3.org/TR/html5/embedded-content-1.html#a-key-part-of-the-content (Note that the /TR/ copy is very out of date. I recommend using the dev.w3.org copy or the whatwg.org/html5 copy.) Then, there is a general guideline about writing alternative texts in section 4.8.1.1.12: 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 information. IMO the wording of 4.8.1.1.9 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 4.8.1.1.12 and provides any useful information for e.g. a blind user. Sure they can. It's certainly not easy or quick to do so, but it's possible. 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 4.8.1.1.12. Agreed. 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). That's A graphical representation of some of the surrounding text, which is an earlier section. So I propose to: - Explicitly treat these two cases in 4.8.1.1.9, requiring to insert no alt text there On the contrary, alt text should be given for the first case. The second case is already handled in a more specific section (and indeed requres empty alt=). - In the part Images whose contents are not known, remove the word unfortunate at the beginning (In some cases), and the first note. I disagree; it is unfortunate. -- Ian Hickson U+1047E)\._.,--,'``.fL http://ln.hixie.ch/ U+263A/, _.. \ _\ ;`._ ,. Things that are impossible just take longer. `._.-(,_..'--(,_..'`-.;.'
[whatwg] Proposal for an addition to the authoring guidance regarding the alt attribute
Section 4.8.1.1.9 describes how alternative text for content images should be written: http://www.w3.org/TR/html5/embedded-content-1.html#a-key-part-of-the-content Then, there is a general guideline about writing alternative texts in section 4.8.1.1.12: 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 information. IMO the wording of 4.8.1.1.9 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 4.8.1.1.12 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 4.8.1.1.12. 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 4.8.1.1.9, 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 4.8.1.1.6 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 4.8.1.1.9, 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.)
