Multi-page digital content handling
|Design||This page proposes a new feature and reviews design options|
|Development||This page describes a feature that is currently in development|
|Documentation||This page documents an existing feature|
 Base Use-Case
- Contributor uploads a multi-page digital object, such as a book, as a multi-page PDF or JPEG.
- System creates multiple single-page information object+digital object children of book information object. Child IO title = page 1, page 2, etc.
- Researcher can view a child (page) information object and has an easy way to switch to the prev/next page (page turner, coverflow, etc.)
 Other possible features
- Flag to activate page turner for only selected IO's?
- Prompt contributor before creating child objects? (i.e. Allow contributor to say "no" and create children manually)
- Prompt contributor for title pattern (grep, placeholder) for "page" names (e.g. "sheet 1, sheet 2...", "photo 1, photo 2...")
 External libraries
- the OpenLibrary project has an AJAX Book Reader which we could integrate
However, we could have a license conflict. The Book reader is licensed under Affero GPL v3, whereas Qubit uses "GPL v2 or later" This makes Qubit forwards-compatible but the BookReader may not be backwards compatible (e.g. the Affero GPL v3 may be viral on the rest of the Qubit project, making it all GPL v3), see http://www.fsf.org/licensing/licenses/gpl-faq.html#v2v3CompatibilityAs of Qubit 1.2, license is AGPL v3 (compatible)
The OAI-ORE standard refers to digital objects containing multiple sub-objects (e.g. multi-page tif or pdf files) as "Compound Digital Objects", so we've chosen to follow this language.
 See Also
- Google reader for design ideas
 Libraries for manipulating multi-page documents
Jpeg and Jpeg2000 do not support multi-page images .
- Can manipulate (convert) and return meta-data (identify) for multi-page tiffs. Meta-data needs to be parsed separately.
With GD lib:
- May be possible to extract multi-page TIFF meta-data via the iptcparse() function though it's unclear what proportion of TIFFs will contain IPTC IIM data. iptcparse() appears to be incompatible with XMP and or "IPTC Core Schema for XMP" data formats.
- Unclear if GD lib allows manipulation of multi-page TIFF files
Note: Multi-page viewing of PDF files is available in most browsers via Adobe Reader.
- GD lib has no support for PDFs. See pdflib below.