Viewer Technology

The scroll viewer technology used in this website is an extension of the standard Seadragon JavaScript image viewer named HandscrollViewer.  HandscrollViewer is optimized to provide a high-level API for viewing very wide Asian handscroll images correctly and with needed additional features.

Below is a list of the optimizing features:

  • Initial display and Home start at the right edge of the image (per handscroll tradition)
  • The navigation control image with a fixed usable height
  • Horizontal auto scroll with custom scroll speed control
  • Optional annotation addition and control for specific images
  • Annotation creation aide
  • Standardized user interface including custom buttons and navigation control
  • Image and annotation information are specified in separate metadata for ease of updating
  • Standard OpenSeadragon functionality (zoom in and out, image drag, full screen mode, etc.) still fully available

The HandscrollViewer source and associated documentation is available in a public open-source project on GitHub (