- From: Leif Halvard Silli <xn--mlform-iua@xn--mlform-iua.no>
- Date: Wed, 18 Aug 2010 20:27:32 +0200
- To: Mark Birbeck <mark.birbeck@webbackplane.com>
- Cc: Ivan Herman <ivan@w3.org>, Shane P McCarron <shane@aptest.com>, martin@weborganics.co.uk, W3C RDFa WG <public-rdfa-wg@w3.org>
Mark Birbeck, Wed, 18 Aug 2010 16:23:54 +0100: > I'm not ignoring your email Leif. :) In fact I was in the middle of > replying when I saw Ivan's response below, and since I think he has > captured perfectly the current stage of the debate, I won't run the > risk of causing confusion! I do not think that *not* thinking about @alt when you makes use of a concrete RDFa vocabulary, makes you create better @alt texts. I will illustrate that by looking at some code of yours: [1] 1.<div about="#me" typeof="foaf:Person"> 2. <span property="foaf:name">Mark Birbeck</span> 3. <a rel="foaf:weblog" href="http://internet-apps.blogspot.com/"> XForms and Internet 4. Applications</a> 5. <a rel="foaf:knows" href="http://www.w3.org/People/Ivan/#me"> Ivan Herman</a> 6. <span rel="foaf:img"> 7. <img src="http://www.formsplayer.com/files/pictures/picture-11.jpg" 8. alt="Picture of Mark Birbeck"/> 9. </span> 10.</div> Critique: A user with a non-visual user agent will have to read the name "Mark Birbeck" twice - once as foaf:name and once inside @alt. But given that the above construct/microformat is foaf:Person, then why should it be necessary to repeat the name? Repeated text is can be a boring for screen reader users. Also, a word such as "picture" also isn't very telling. If you took your use of @alt into the overall picture when creating you foaf:Person microformat, then it is possible that you could have gotten rid of the repetition, perhaps you could have had an entirely empty @alt, and perhaps you could - if RDFa supported it - constructed a useful triple with @alt as object. Examples. (1) Empty @alt example + no repetition: <span role="img"> <span property='foaf:name'>Mark Birbeck</span> <span rel='foaf:img'> <img src='http://www.example.com/i.png' alt=''/> </span> </span> (2) Non-empty @alt with useful info + no repetition + another triple. <span role="img"> <span property='foaf:name'>Mark Birbeck</span> <span rel='foaf:img'> <img src='http://www.example.com/i.png' property='foaf:Image' alt='Portrait photo.' content="Portrait photo" /> </span> </span> (3) The result in (2) can actually be achieved without using @role or extra span elements: <span rel='foaf:img'> <img src='http://www.example.com/i.png' property='foaf:Image' alt='Portrait photo' content="Portrait photo" /> </span> Of course, the reason I repeat @alt inside @content, is due to how RDFa works today. [1] http://webbackplane.com/mark-birbeck/blog/2009/04/getting-started-with-rdfa -- leif halvard silli
Received on Wednesday, 18 August 2010 18:28:10 UTC