- From: James Graham <jg307@cam.ac.uk>
- Date: Tue, 15 Apr 2008 23:51:01 +0100
- To: Steven Faulkner <faulkner.steve@gmail.com>
- CC: public-html@w3.org, John Foliot <foliot@wats.ca>, Tomas Caspers <tomas@tomascaspers.de>, wai-xtech@w3.org, wai-liaison@w3.org
Steven Faulkner wrote: >> There is *absolutely no practical difference* to the UA between omitting >> the alt="" attribute altogether, and having the alt="" attribute set to >> some magical reserved value. They are functionally identical, and user >> agents can get as much information from either. > > No. you are wrong. > > if <img alt=""> signals to an AT that an image can be safely ignored > (which is current usage). > then <img noalt> could signal that image should not be ignored by AT > <img> signals that neither can the image safely be ignored or that it > should not be ignored as it may contain something important. I think this makes the incorrect assumption that a UA will be able to make a useful distinction between the @noalt case and the missing alt attribute case. In practice @noalt will end up on images that should have alt="" (because e.g. of developers misunderstanding the spec) and images that should not be ignored will have neither @alt nor @noalt. Therefore in the absence of an alt attribute or in the presence of a noalt attribute, the UA should do its level best to supply some useful information about the image, hopefully using something better than the crummy "read the filename" algorithm that AT vendors have employed to date. Can you give an example of the differences in behavior you would expect? -- "Mixed up signals Bullet train People snuffed out in the brutal rain" --Conner Oberst
Received on Tuesday, 15 April 2008 22:51:52 UTC