Accessibility

In a PNG or a JPG the text is pixels: TalkBack, VoiceOver or Narrator cannot read it. In an .oim every text layer travels as real text, in every language, inside the signed file. <oim-player> uses that to make the work readable by a screen reader, with no extra work for most layers.

What a screen reader hears

1. The work, announced as a figure. Its name is the document description in the active language; without one, the first text; without any text, "Image".
2. The texts, in visual reading order: top to bottom, then left to right (layers within 8 px vertically count as one row). Each is read in the active language, with its lang set, so the voice changes with it.
3. Pictures with a description (image and svg layers with alt), at their place in that order.
4. Interactive layers with active actions, as buttons named by their text or alt, reachable with the keyboard (Enter or Space does what a click does).

Skipped: layers marked decorative, pictures without a description, the flattened base image and the duplicated tracks of a scene loop.

The reading layer is built once when the work loads and again when the language changes. It costs nothing per frame.

Describing a work

Field	Where	Type	Meaning
alt	layer style	{ [lang]: string }, up to 300 characters each	What the picture shows
decorative	layer style	boolean	Screen readers skip it; wins over alt
description	document root	{ [lang]: string }, up to 1000 characters each	Summary of the whole work

• Missing language in alt: the document's primary language is used; if that is missing too, the picture is skipped.
• A blank description counts as none.
• All three are inside the signature: changing them breaks it, like any other field.
• They are plain text. The player writes them with textContent/setAttribute, never as HTML.

Texts need nothing: they are read as they are.

In OIM Studio and the MCP

• Studio: select an image or SVG → Accessibility: a description per language and a Decorative checkbox. A warning shows while a picture has neither. The work's description is typed in the export dialog.
• MCP: alt and decorative are accepted when creating or updating layers; tools return accessibility: [{ id, mensaje }] for pictures left without either.

Added in contract 1.16.0. Files written before it are read the same way, minus the descriptions they do not have.