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Re: LONGDESC in HTML5?

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From: E.J. Zufelt
Date: Sep 25, 2010 3:48AM

On 2010-09-25, at 5:25 AM, Vlad Alexander (XStandard) wrote:

> I wrote: "Unfortunately, we are still talking about @alt and @longdesc as "image descriptions" with the only difference being the number of characters typed."
>
> Josh wrote: "What else would you like them to do?"
>
> Let's take a look at the text from this article:
> http://webaim.org/techniques/images/longdesc
>
> Article text: "In some instances, an image is too complex to describe in a few words."
>
> The purpose of alt is not to "describe" images but to replace them. Alternate text can be quite different than a description of an image.
>
> Article text: "Although there does not appear to be any limit to the length of text in an alt attribute, alt text is meant to be relatively short, so it would be an abuse of this attribute to write more than a few words, or, at most, a few short sentences."
>
> Why? @alt is part of document content just like paragraphs. If you don't impose arbitrary limits on paragraphs, why impose them on alt. The author should decide on the length of alt text.
>
> Article text: "The answer, then, is to provide a brief alt text description of the image and then provide a longer description elsewhere."
>
> This statement implies that alt and longdesc are the same except one is longer than the other.
>
> We need to start calling content in the @alt attribute "textual substitute" for an image, and content appearing in the @longdesc as a "description" if we ever want alt to be authored correctly and longdesc to be used.
>
I agree completely that we need to call content in the alt attribute ""textual substitute" in order for there to be a clear differentiation, The difference is * not * short and long description, but image replacement text and image description text.

Image description text is relative to the image, whereas image replacement text is relative to a specific usage of an image within a specific piece of content.

I think that we also need to specify that alt ought to be able to point to structured content, in case the image replacement needs to be structured text (lists, etc.).


Everett