- From: Lachlan Hunt <lachlan.hunt@lachy.id.au>
- Date: Mon, 19 Nov 2012 13:19:31 +0100
- To: public-html <public-html@w3.org>
At the HTML F2F, I was asked to provide rationale for my previously filed formal objection to "HTML5: Techniques for providing useful text alternatives" (alt-techniques). (Note: The objection was filed on my own behalf, not on behalf of my employer) http://dev.w3.org/html5/status/formal-objection-status.html http://lists.w3.org/Archives/Public/www-archive/2011May/0051.html This email covers both of my objections to the alt-techniques spec, regarding publishing on the Rec track and contradicting HTML5. This outlines a few areas of contention and compares equivalent sections of both the alt-techniques and HTML5 drafts. In each case, the section heading and normative requirement from Alt-Techniques, and (where applicable) the equivalent heading and requirement HTML5 are stated, followed by a comment about the problem and proposed solutions. I have not had time to go through and analyse the complete specification for differences, so the following are selected examples sufficient to illustrate my problem with the alt-techniques draft and justify my objections. --- Alt-Techniques: *Abstract* "All normative content in the HTML5 specification, unless specifically overridden by this specification, is intended to be the basis for this specification." I object to any normative content of the alt-techniques draft overriding normative requirements in HTML5. Proposed Solution: 1. Remove this clause "unless specifically overridden". 2. Resolve any significant differences (some of which are discussed below) by either changing alt-techniques, or by pursuing relevant changes in HTML5. --- Alt-Techniques: *A link or button containing only an image* "When an a element that is a hyperlink, or a button element, has no text content but contains one or more images, the alt attributes must contain text that together convey the purpose of the link or button." HTML5: *A link or button containing nothing but the image* "When an a element that creates a hyperlink, or a button element, has no textual content but contains one or more images, the alt attributes must contain text that together convey the purpose of the link or button." -- html5 This section contains an unnecessary normative redefinition of a requirement in HTML5. The requirements are phrased slightly differently, but have effectively the same meaning. Proposed solutions: 1. Mark this section in alt-techniques as non-normative to ensure that HTML5 takes precedence in the event of any conflict. 2. Include a link to the equivalent section in HTML5. --- Alt-Techniques: *Graphical representations: charts, diagrams, graphs, maps, illustrations* "The full text alternative may be provided in the alt attribute, or a shorter text alternative may be provided in the alt attribute or in a programmatically associated element, and a longer programmatically associated text alternative provided in the same document or in a linked document." HTML5: *A phrase or paragraph with an alternative graphical representation: charts, diagrams, graphs, maps, illustrations* "The text must be given in the alt attribute, and must convey the same message as the image specified in the src attribute." This section is incompatible with the requirements in HTML5 because it provides conflicting advice to users about the same types of images. Proposed solutions: 1. Mark this section in alt-techniques as non-normative to ensure that HTML5 takes precedence in the event of any conflict. 2. Make the advice compatible by either changing alt-techniques, or by pushing for a compatible change in HTML5. (I take no position with regards to which advice is better - just that the normative requirements in HTML5 and the advice in alt-techniques should be not contradict each other.) 3. Include a link to the equivalent section in HTML5. --- Alt-Techniques: *Images of text* "Sometimes, an image only contains text, and the purpose of the image is to display text using visual effects and /or fonts. It is strongly recommended that text styled using CSS be used, but if this is not possible, in most of these cases, the content of the alt attribute should consist of the same text as written in the image itself." HTML5: *Text that has been rendered to a graphic for typographical effect* "Sometimes, an image just consists of text, and the purpose of the image is not to highlight the actual typographic effects used to render the text, but just to convey the text itself. "In such cases, the alt attribute must be present but must consist of the same text as written in the image itself." This section contains an unnecessary normative redefinition of a requirement in HTML5. The requirements are phrased slightly differently, but have effectively the same meaning. Proposed solutions: 1. Mark this section in alt-techniques as non-normative to ensure that HTML5 takes precedence in the event of any conflict. 2. Include a link to the equivalent section in HTML5. --- Alt-Techniques: *Images that include text* "Sometimes, an image consists of a graphics such as a chart and associated text. In this case it is recommended that the text in the image is included in text alternative." It's not entirely clear if this is meant as a normative requirement or not. Although the term "recommended" is included, it is not highlighted as an RFC2119 term. But for the purposes of this email, I will assume it is intended to be a normative requirement. I could not identify any specific section in HTML5 that correlates with this advice specifically, but HTML5 does require, for charts and graphs, that the alt text convey the same message as the image. It seems, therefore, that this section in alt-techniques is a more specific application of the general technique required in HTML5, and is thus effectively a redefinition of existing requirements. Proposed solutions: 1. Mark this section in alt-techniques as non-normative to ensure that HTML5 takes precedence in the event of any conflict. --- Alt-Techniques: *A purely decorative image that doesn't add any information* "Purely decorative images must be marked up so they can be ignored by assistive technology with a null alt attribute (alt="") or preferably use CSS techniques. If the image isn't providing the user any informative content or enhancing greater understanding of the content, then the alt attribute must be empty." HTML5: *A purely decorative image that doesn't add any information* "If an image is decorative but isn't especially page-specific ... the image should be specified in the site's CSS, not in the markup of the document. "However, a decorative image that isn't discussed by the surrounding text but still has some relevance can be included in a page using the img element. Such images are decorative, but still form part of the content. In these cases, the alt attribute must be present but its value must be the empty string." This section contains an unnecessary normative redefinition of a requirement in HTML5. The requirements are phrased slightly differently, but have effectively the same meaning. Proposed solutions: 1. Mark this section in alt-techniques as non-normative to ensure that HTML5 takes precedence in the event of any conflict. 2. Include a link to the equivalent section in HTML5. --- Alt-Techniques: *Icons* "In some cases, the icon is supplemental to a text label conveying the same meaning. In those cases, an empty alt attribute must provided. "In other cases the icon adds emphasis to text content that needs to be conveyed textually, In such cases a text alternative must be provided." HTML5: *A short phrase or label with an alternative graphical representation: icons, logos* "In some cases, the icon is supplemental to a text label conveying the same meaning. In those cases, the alt attribute must be present but must be empty. "In other cases, the icon has no text next to it describing what it means; the icon is supposed to be self-explanatory. In those cases, an equivalent textual label must be given in the alt attribute." This section contains an unnecessary normative redefinition of a requirement in HTML5. The requirements are phrased slightly differently, but have effectively the same meaning. Proposed solutions: 1. Mark this section in alt-techniques as non-normative to ensure that HTML5 takes precedence in the event of any conflict. 2. Include a link to the equivalent section in HTML5. -- Lachlan Hunt http://lachy.id.au/
Received on Monday, 19 November 2012 12:19:58 UTC