- From: Alan Chuter <achuter@technosite.es>
- Date: Mon, 23 Nov 2009 14:12:31 +0100
- To: Public BPWG <public-bpwg@w3.org>
- CC: achuter@technosite.es
I would like to emphasise that my comments on this matter (of some weeks ago now) should not be taken to call for any changes to the document and I do not expect them to be addressed by the group. best regards, Alan Alan Chuter wrote: > The document says "Canvas ... is not inherently accessible and so should > not be used as the sole means of conveying information." [1] > > Perhaps the word "alternative" is needed here, "If you need to use > canvas, then provide an alternative." > > I think that as this is about dynamic graphics the document should also > add the proviso that the alternative should be updated as the image is > redrawn, if that changes its meaning. How this is done in canvas I don't > know, probably by the same script that updates the image. Updates to the > DOM (which would be used for the alternative) are detected by some > current mobile screen readers. This also applies to SVG. SVG supports > accessibility but in practice it requires a text alternative for the > whole image. > > Another solution might be to require that it be used in an > accessibility-supported way, as defined by WCAG [2]. > > [1] http://www.w3.org/TR/mwabp/#bp-canvas > [2] http://www.w3.org/TR/WCAG20/#accessibility-supporteddef > -- Alan Chuter Departamento de Usabilidad y Accesibilidad Consultor Technosite - Grupo Fundosa Fundación ONCE Tfno.: 91 121 03 30 Fax: 91 375 70 51 achuter@technosite.es http://www.technosite.es
Received on Monday, 23 November 2009 13:16:36 UTC