- From: Boris Zbarsky <bzbarsky@MIT.EDU>
- Date: Wed, 14 May 2008 16:07:27 -0500
- To: Matt Morgan-May <mattmay@adobe.com>
- CC: HTML Working Group <public-html@w3.org>, W3C WAI-XTECH <wai-xtech@w3.org>
Matt Morgan-May wrote: > Visual UAs wouldn't require any new behavior. I don't believe that's necessarily true. Visual UAs care about @alt in various situations; at the very least any time images are disabled, if the image data can't be loaded for some reason, or if the image is in a graphics format the UA doesn't support. Granted, these are somewhat corner cases for visual UAs in terms of how often our users hit them, but nevertheless they are ones we try to take pretty seriously. > And not whether that is intentional, for which I'm proposing @noalt, or > accidental, in which case AT would need to attempt to repair the missing > data. The implications for these two scenarios is very different at the > UA/AT level. I'm finding this argument somewhat compelling, as our armchair Aristotelian arguments have gone, to be honest. So if I understand correctly, the proposal here is that from a validator's standpoint, precisely one of @alt and @noalt must be present on every <html:img>. Is that correct? I think I saw an argument go by that claimed that this is equivalent to having lack of @alt imply @noalt, but that claim does assume that everyone is producing valid documents... The other concern I can see here is that authors would sprinkle the @noalt pixie dust the way some claim the sprinkle the alt="" or bogus alt value pixie dust. This part could use a bit of validator usability study. > There's nothing wrong with getting content providers to show their colors, > IMO. True, as long as it doesn't interfere with actual accessibility improvements (both in the sense of resource diversion and in the sense of color-showing involving changes that actually reduce accessibility). Evaluating whether such interference occurs can be nontrivial, of course. -Boris
Received on Wednesday, 14 May 2008 21:08:16 UTC