OpenSeadragon - Web-based viewer for zoomable images, implemented in pure JavaScript

OpenSeadragon is an open-source, web-based viewer for high-resolution zoomable images, implemented in pure JavaScript, for desktop and mobile. It supports several image serving protocols out of the box and is actively adding support for more. It has support for Zoom and Pan, Overlay, Rotation, International Image Interoperability Framework, Open street maps, Tiled map service and lot more.