REQUIREMENT	How does IIIF support this?	OpenSeadragon	Digirati Universal Viewer (Wellcome)	Mirador	IA BookReader	Diva.js
IIIF Compliant	n/a	Yes	Yes	Yes	Not in the form most of us know it, but apparently there is an IIIF-compliant fork under construction - https://github.com/aeschylus/IIIFBookReader	Yes (as of Sep 2015)
Images in sequence (regular sized)	sequence informally, viewingHint might help with regularity/irregularity distinction	Yes: Sequence Mode (does not care about size)		Yes	Yes	Yes
Images in sequence (irregular sized)	sequence informally, viewingHint might help with regularity/irregularity distinction	Yes: Sequence Mode (does not care about size)		?	Yes, but there are problems displaying irregular sized images in 2-page mode.	Yes
Images side-by-side (book pages)	sequence viewingHint = "paged"	Yes Multi image		Yes	Yes	Yes
Single images	supported	Yes		Yes	Yes	Yes. But still have page nav chrome.
Manuscripts with foldouts and inserts		With local development		?	Yes, but this is a variation of "irregular sized" images with no animations/transitions going from opened/closed states. An example can be found here: http://pudl.princeton.edu/objects/9880vq97z	No
Transcripts and translations, overlaid or shown side-by-side	external Annotation Lists referenced in the otherContent property	Not natively. Side-by-side could be achieved with Multi image. Overlay can be used for HTML.		Not Yet	Not natively. The LSE in London have patched it to do this. http://digital.library.lse.ac.uk/	Not natively. Duke extended it with some JS, e.g.: http://library.duke.edu/digitalcollections/rubenstein_hdims01001/
Pan and zoom		Yes	Yes	Yes	Yes	Yes
Navigate by thumbnail grid		Not natively.	Yes	Not Yet	Yes	Yes
Jump to page		Not natively.	Yes			Yes
Keyword search of text (OCR'd), highlight search term		No	Yes		Yes in the full (PHP-enhanced) version	Not natively, but possible, e.g. "Search Manuscript" tab on http://cantus.simssa.ca/manuscript/133/?folio=001r
Export/download JPG or PDF of single page, range of pages or whole item		No			Yes	JPG of single page: Yes Range of pages: No Whole item: No PDF (any): No
Swipe/gesture navigation for tablet/mobile		To an extent			No but someone was working on this?	Yes
Structural navigation (links for TOC, chapters, etc)		No	Yes	Yes	No	No
Page # input		No			Yes (via the url... adding an interface would be trivial)	Yes
Slider navigation		Yes Image Reference Strip and Collection Mode			Yes	Yes (iframe scroll bar; this is the primary means for nav)
Embed links		No				No
Embed viewer		Yes	Yes (https://vimeo.com/126596158)			No
Keyboard shortcuts		Yes			Yes	Yes
1up view		Not Natively		Yes	Yes	Yes
2up view		Not Natively		Yes	Yes	Yes
Plain text view		No				No
Horizontal scroll mode		Yes			Yes	Yes
Vertical scroll mode		No?			No	Yes
Full screen view		Yes		Yes	Navigation etc can be hidden	Yes
Help text		Yes			? In principle.	Not natively.
Image rotation		Yes			No	Yes

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