- From: James Graham <jg307@cam.ac.uk>
- Date: Sat, 16 Aug 2008 18:33:51 +0100
- To: Steven Faulkner <faulkner.steve@gmail.com>
- CC: Ian Hickson <ian@hixie.ch>, W3C WAI-XTECH <wai-xtech@w3.org>, "public-html@w3.org WG" <public-html@w3.org>
Steven Faulkner wrote: > hi jgraham, > yes, my bad you are correct on the title/description. > > >> I believe the spec currently requires that flickr set @alt={photo} or >> similar. >> > > so does this mean it is what is required in these cases or you are not > clear on what is required? > Well I guess I was wrong in a sense because it depends entirely on what context the photo appears in. I was only considering the individual photo page case but actually there are a fairly large number of distinct cases. On the user's home page (e.g. [1]) the photos are the sole contents of a link so per section 4.7.2.1.1. the alt text must "convey the purpose of that link". This suggests that the alt text in this case could be "Photo page" or similar. I guess adding the title of the photo e.g. "Photo page for Mario's Bike" would help in the case where someone wanted to query the images out of context but would be repetition in the case where the page was being read linearly. However I'm not sure that the spec has anything to say on the topic. On the individual photo page (e.g. [2]) the photo is not a link and the image is clearly a key part of the surrounding content. Therefore Section 4.7.2.1.8. applies. At this point the alt text should contain a textual equivalent of the image unless no such alternate text is available. Clearly (from observing flickr) none of the fields provided are reliably used to provide textual equivalents of images. Therefore we are always in the case where there is no textual equivalent avaliable so we must supply an alt that provides a categorization of the image delimited by curly braces e.g. alt={photo} (there is no requirement that the exact string {photo} be used but it must be a classification of the image). On some aggregate photo pages such as a group pool or a user's set (e.g. [3], [4]) the images are again the sole contents of links and so 4.7.2.1.1. again applies. In this case however, there is no context to give e.g. the name of the photo so using something like alt="Photo Page for New Forest Pony". Arguably the text "Photo Page" is unnecessary although this does create a (relatively common) edge case when the photo has no title (note also the requirement to be careful here to avoid using titles that are delimited by curly braces directly in @alt). On some search pages, explore pages calendar pages and explore front page (e.g. [5], [6], [7]) the photo is again the sole contents of a link but the other information about the photo is already supplied. This case is quite close to the user's stream page case. Did I miss any cases? [1] http://flickr.com/photos/jgraham [2] http://www.flickr.com/photos/andrerabelo/70458366 [3] http://flickr.com/groups/utata/pool/ [4] http://flickr.com/photos/rebba/sets/72157594157565155/ [5] http://flickr.com/search/?q=sigur+ros&s=int [6] http://flickr.com/explore/interesting/2008/08/15/ [7] http://flickr.com/explore/
Received on Saturday, 16 August 2008 17:34:29 UTC