The Harvard Library Viewer is a new image viewing platform based on the open source Mirador project and compatible with the IIIF (International Image Interoperability Framework) standard. Harvard Library Viewer provides access to book-like digital objects (manuscripts, broadsides, photograph albums, musical scores, etc.) hosted by the Harvard Library Digital Repository Service (DRS) or any other repository that is IIIF-compatible. 

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What functions are available? 

Besides core page-viewing capabilities such as page-turning navigation, table of contents, full text search and print (PDF download), the Harvard Library Viewer implements frequently-requested features, including:

• Two-page and scroll views
• Improved page image rotation, zooming and panning
• Comparison of IIIF-compatible documents
  

And the new Viewer is a platform that can be expanded in the future to support new capabilities for research and teaching, such as annotation and document portfolios, as well as expanded comparison of compatible text and images from collections at Harvard and internationally.

Switching between the Viewer and Old PDS

The new Viewer interface will automatically display for page-turned objects discovered through Harvard Library catalogs and websites. For the time being, access to the old Page Delivery Service (PDS) interface will remain available via a "View in PDS" link in the Viewer top menu.

Large documents and serials with 5000 pages or more will continue to display in the old PDS interface for now, until migration to PDS list objects is complete.

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Navigating an object

This screenshot shows basic options for navigating pages in an image object. Click the image to enlarge.

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The near operator will match terms that are within 100 words of each other, regardless of their order.

Tip: Use * as a wildcard. Examples: cat*, oper* and Harv*

Viewing multiple image objects

You can use the Viewer workspace to compare multiple image objects. This can include image objects at Harvard or external sources, as long as they come from a IIIF-compatible repository. At this time, page-turned objects stored in DRS and delivered by the Harvard Library Page Delivery Service (PDS) are IIIF-compatible. 

In this release of the Viewer, compatible image objects can be loaded directly into the viewer if you know the object’s manifest url. This url retrieves a manifest – a collection of presentation and structural metadata that the Viewer uses to display the object.  (A future release will let you search for compatible image objects.)

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