- From: Robert J Burns <rob@robburns.com>
- Date: Sat, 3 May 2008 13:13:23 +0000
- To: HTML4All group <list@html4all.org>, HTML Working Group <public-html@w3.org>
Looking over the lengthy discussions on the alt issue, it seems to me there's some fundamental misunderstandings going on: especially regarding the omission examples. Since alt is properly used as an alternative when the doc.ument is not available (leaving longdesc and other mechanisms for other textual content), then the often sited Flickr example doesn't really apply. I'm more familiar with iPhoto (and its integration with .mac), so let me use that as an example. iPhoto extracts sometimes hundreds of photos from my camera in a bulk operation. With a few clicks I can publish those photographs to the web as a web gallery. These photographs are presented as a web gallery along my other web galleries. A visitor to the web gallery sees the following: 1) the initial web gallery page with a 'key' photograph for each gallery (like a photo album). This key photo constitutes a navigable link to view the thumbnails of all of the photos in the gallery. It is a photo that should therefore have appropriate value for its alt attribute. Something along the lines of "view entire x gallery", where x is the name I've given to the gallery in iPhoto. 2) next on the gallery page, each photo in the gallery is represented by a thumbnail. By clicking on the thumbnail a higher resolution and larger photo is loaded. Again, these thumbnails require alt text. Something like "view fullsize image" or view image y fullsize" where y is the name of the photo. The initial name of the photo is automatically generated by iPhoto or my camera and usually in the form IMG_####.jpg. This means the alt attribute would look like this: ‘alt='view image "IMG_1234" fullsize”. If I changed the name of the photo to be more title-like it might instead be: ‘ alt='view image "Joe at the Beech" fullsize' ’. 3) Finally the image is displayed full size with a series of controls for downloading and viewing the next image. Here the image "Joe at the Beech" would properly have the attribute ‘alt='return to contact sheet of the entire gallery '’. Here the alt is easily generated by the software authoring tool. The controls on the page are iconic and therefore also require alt text: and again it is alt text automatically derived from the title of the photos (or simply "download photo", "next photo", and "previous photo" to avoid adding the titles of the relevant three photos). In this iPhoto scenario it is very rudimentary for iPhoto to add the appropriate alt text to every one of these photos. It doesn't matter that I'm adding hundreds or even thousands of photos to my html document with just a few clicks in a GUI authoring tool. The user of iPhoto need not know anything about HTML4, HTML5, or have ever heard of the W3C. Where things might matter is with the optional longdesc attribute, or with the image format supported description and title metadata. Here, iPhoto allows me to add descriptions to my photos and give them appropriate titles. However, that information remains in the image supported metadata (inside the jpeg file) and is not included as a document fragment with a longdesc attribute reference pointing to the document fragment. Here, it may be cumbersome for user (author) to provide descriptions of every photo of hundreds uploaded to the web. However, it is even more disappointing for an author who has already included such descriptions to have their authoring tool leave them out of the generated content. Again, this has nothing to do with the @alt attribute however. The @longdesc attribute is optional in HTML4 (and clearly some mechanism to explicitly associate embedded media with semantically rich descriptions should be included in HTML5) If Flikr has something different that I'm missing, then I think someone needs to elaborate how Flikr works that would necessitate some different approach and an optional alt. Take care, Rob
Received on Saturday, 3 May 2008 13:14:02 UTC