- From: Aryeh Gregor <Simetrical+w3c@gmail.com>
- Date: Mon, 18 Apr 2011 18:35:16 -0400
- To: Maciej Stachowiak <mjs@apple.com>
- Cc: HTMLWG WG <public-html@w3.org>
On Mon, Apr 18, 2011 at 4:33 PM, Maciej Stachowiak <mjs@apple.com> wrote: > After considering all these arguments, it seems established that there > is a valid use case for allowing the alt attribute to be omitted when > the generator mechanism is specified. This use case makes for a > moderately strong objection. However, the claim of negative > consequences to disallowing this use case was somewhat weakened by the > lack of concrete evidence that bogus values have been used in the past > or would be used in the future. It doesn't affect the validity of the decision, but I'd like to provide some concrete evidence on this point, in case this decision winds up being reopened. Both MediaWiki and vBulletin (the two web software packages I'm most familiar with) automatically add alt="" to all user-provided images. For MediaWiki, hitting "Random article" a couple of times on Wikipedia gets an article with an image. You can look at the HTML for the current version and note that the two images on the bottom right all have alt="": http://en.wikipedia.org/w/index.php?title=Cwm_Penmachno&oldid=383061670 If you look in the source code, you'll find that the lines generating these images are as follows: """ [[File:Cwm Penmachno - geograph.org.uk - 147746.jpg|thumb|Houses in Cwm Penmachno, showing the quarry behind.]] [[Image:cwmpenmachno1969.jpg|thumb|Cwm Penmachno from the south (quarry in foreground), 1969.]] """ http://en.wikipedia.org/w/index.php?title=Cwm_Penmachno&action=edit Since no alt text was provided using the "|alt=" parameter, empty alt text is automatically inserted so that the page validates. In older MediaWiki versions, the caption would be repeated in the alt text, leading to the caption being read twice by screen readers -- again, the motivation being to ensure that it validates. This was changed to empty alt text so that at least it wouldn't be repeated. <https://bugzilla.wikimedia.org/show_bug.cgi?id=368> As for vBulletin, you can look at the signature images here (for instance) to see that they automatically have alt="": http://www.twcenter.net/forums/showthread.php?t=410326 vBulletin (unlike recent MediaWiki versions) doesn't allow users any way to provide alt text even if they wanted to. The image syntax is "[img]http://...[/img]", with no place to provide alt text.
Received on Monday, 18 April 2011 22:43:10 UTC