DWV (DICOM Web Viewer) is an open source zero footprint medical image viewer. It uses only javascript and HTML5 technologies, meaning that it can be run on any platform that provides a modern browser (laptop, tablet, phone and even modern TVs). It can load local or remote data in DICOM format (the standard for medical imaging data such as MR, CT, Echo, Mammo, NM...) and provides standard tools for its manipulation such as contrast, zoom, drag, possibility to draw regions on top of the image and imaging filters such as threshold and sharpening.
