Image pages/Data syntax

Proposals for syntax for the data to be stored on Image pages

Requirements:

Image caption, which may include wiki links or formatting (optional)
ALT text, which will be plain (required)
link to an optional larger image, so that the article page which displays a thumnail can append to the caption "See a Template:Larger image"

Unresolved questions:

is it safe to assume that all instances of an image will want the same caption?
might some instances want no caption?
- These can both be resolved by allowing for specification of multiple captions, and allowing some selection of any (or none) of them.

Old proposal

all text up to the first ------- on the image page becomes the caption.

Old proposal with added ALT

We can do better than that: make all text up to the first ---- be the caption, and all text between the first ---- and the second ---- be the "alt text" (text when no image downloaded). That way we'll do better with blind or partially sighted readers who are using text-to-speech interfaces and the like. The title (mouseover text) could be something like "click here for a description", I guess - or a repeat of the caption.

For instances with no caption, simply make ---- the first text in the page. I think it's safe to assume that all instances of an image will want the same caption, in practice if not in theory.

Brackets and keywords

Several blocks delimited by "----" is starting to get messy, but you're right -- we need to provide ALT text. How about:

Caption{ }

Alt{ }
Larger{ }

on the image page?

Heading markup & #LARGER

Another option:

#LARGER [[larger-version.lpg]]

== Caption goes here ==
This is alt text

This is not alt text.

I like the idea of using == == to delineate a caption, which seems intuitive to me. No == == - no caption (but first para is still alt text). MyRedDice

Some of my thoughts: --Brion VIBBER 05:50 12 May 2003 (UTC)

Caption

This is a caption section. It's not alt text, but a caption that will appear below the image if there is a section with a header so named in the desc page.

The caption may even be multiple lines or paragaphs; it is terminated by the end of the page or the next section header.

Alternate caption

Multiple captions can be provided, and selected among when the image is used. Perhaps something like [[Image:Some image.png|caption:Alternate caption]]?

Image map

If there's an "Image map" section, the image will be a clickable image map. Lines in a bullet list like this:

rect 0,0 80,20 Some captioned thing
circle 100,120, 60 Alt text here...
poly 1,1, 50,60, 90,70, 40,20 Nowhere else please we're done

Cf HTML client-side image map syntax. The text between the section header and the list will be inserted as alternate text in the map.

Technical notes

The caption and image map data probably will be parsed on page save and then stored in the image table, so loading a page that uses images doesn't have to load up and parse a gajillion pages.

An image with no caption can go directly in as an inline <img> tag. An image with a caption will be a <div>, necessarily a block-level element. We should extract the size of image files via php's getimagesize() so we can generate appropriate width and height attributes; this is helpful for the browser to set up layout, and necessary to keep long captions from grossly exceeding the width of their images.

Localization

The "Caption" and "Image map" section names should be localizable, as the "image" namespace is.
The "rect", "circle", and "poly" for image maps are specific to HTML. It's possible they should be left as-is, but they could be localizable as well.
None of the above should be case-sensitive.