IIIF Tools (src/tools/iiif.js)

Helper functions for converting IIIF manifests into MEI XML documents, validating manifests, and extracting pages.

addPage(canvas, canvases, dimension, n, file, meiSurfaceTemplate, hasItems)

Adds a page (<surface>) to the MEI file from a IIIF canvas.

Parameters:

  • canvas {Object} — IIIF canvas object
  • canvases {Array} — Array of all canvases (for dimension lookup)
  • dimension {Array} — [width, height] for the image
  • n {number} — Page number (1-based)
  • file {Document} — The MEI XML document to modify
  • meiSurfaceTemplate {Document} — MEI surface template XML
  • hasItems {boolean} — true if IIIF Presentation 3 (items), false if Presentation 2 (images)

Behavior:

  • Extracts the label and dimensions of the canvas.
  • Determines the info.json URI based on IIIF version.
  • Generates unique IDs for <surface> and <graphic>.
  • Clones the surface template, sets attributes, and appends it to the MEI <facsimile>.

iiifManifest2mei(json, url, parser, state)

Converts a IIIF manifest JSON object into an MEI XML document.

Parameters:

  • json {Object} — IIIF manifest JSON
  • url {string} — Manifest URL
  • parser {DOMParser} — XML parser instance
  • state {Object} — Application state (for page dimensions)

Behavior:

  • Loads MEI file and surface templates asynchronously.
  • Sets up MEI metadata (title, source, date, etc.) from the IIIF manifest.
  • Attempts to extract shelfmark and composer from IIIF metadata.
  • Iterates over canvases (Presentation 2) or items (Presentation 3) and adds each as a surface/page using addPage.

Returns:

  • Promise<Document> — Resolves to the generated MEI XML document.

checkIiifManifest(json)

Checks if a given JSON object is a valid IIIF manifest (Presentation 2 or 3).

Parameters:

  • json {Object} — IIIF manifest JSON

Returns:

  • {boolean} — true if the manifest is valid, otherwise false.

Validation logic:

  • Verifies IIIF context (@context)
  • Checks manifest type (sc:Manifest)
  • Ensures an ID (@id) is present
  • Confirms presence of sequences (IIIF v2) or items (IIIF v3)

getPageArray(mei)

Extracts an array of page objects from an MEI XML document.

Parameters:

  • mei {Document} — MEI XML document

Returns:

  • {Array} — Array of page objects with:
    • uri — Image target URI
    • id — MEI surface ID
    • n — Page number
    • width, height — Dimensions
    • hasSvg — Whether the surface has an embedded SVG
    • hasZones — Whether the surface contains zones

Example Usage

import { iiifManifest2mei, checkIiifManifest, getPageArray } from '@/tools/iiif.js'

// Validate a manifest
const isValid = checkIiifManifest(manifestJson)

// Convert IIIF manifest to MEI
const meiDoc = await iiifManifest2mei(manifestJson, manifestUrl, parser, state)

// Extract page data
const pages = getPageArray(meiDoc)