Osimis Web Viewer plugin

This plugin by Osimis extends Orthanc with a Web viewer of medical images, with more advanced features than the basic Orthanc Web viewer plugin. The Osimis plugin adds tools for measuring, for viewing multiple series, and for split-pane.

Importantly, contrarily to the basic Orthanc Web viewer, CE marking is available. By buying such a CE marking, this viewer can be used for diagnostic purpose.

For general information, check out the official homepage of the plugin. Also check out the source code.

How to get it

The Osimis Web viewer is part of the Windows installers.

For Linux users, you’ll find it in the osimis/orthanc Docker images or you can download the LSB (Linux Standard Base) binaries here.

The compilation process is quite complex since it requires to build first the frontend and then the backend. All information can be found in the source code.


On Windows, the plugin is enabled by default and will work out-of-the-box.

If you’re using the osimis/orthanc Docker image, you’ll have to define the WVB_ENABLED environment variable to true.

On plain GNU/Linux distributions (i.e. if not using Docker), the Osimis Web viewer will only work with LSB (Linux Standard Base) Orthanc binaries that can be downloaded from here (that will work with most recent GNU/Linux distributions). Once Orthanc is installed, you must change the configuration file to tell Orthanc where it can find the plugin: This is done by properly modifying the Plugins option. You could for instance use the following configuration file:

  "Name" : "MyOrthanc",
  "Plugins" : [

Orthanc must of course be restarted after the modification of its configuration file.

Once a DICOM study is opened using Orthanc Explorer, a yellow button entitled Osimis Web Viewer will show up. It will open the Web viewer for that particular study. See also the interactive demonstration on the official homepage of the plugin.

Advanced options

The configuration of the Web viewer can be fine-tuned by adapting some options in the configuration file.


  • What video formats are supported by the Osimis Web Viewer ?

    The set of codecs supported by the Osimis Viewer is an intersection of the sets of codecs supported by the DICOM standard and those supported by the web browsers. In short, this mostly comes down to just MPEG-4.

  • Where are the annotations stored ?

    Annotations are stored in metadata (id 9999) in a custom format. Note that annotation storage is disabled by default and can be enabled by setting "AnnotationStorageEnabled": true in the configuration file.

CE marking

Legally, in Europe, the Osimis Web viewer cannot be used for medical usage unless you purchase the CE marked version by Osimis. If you are located outside of Europe, you should check your local regulation: However, you are most likely not allowed to use it for medical usage as well.

Although the free and open-source version of the Osimis Web viewer offers the same feature scope, CE marking requires a “supplier-end user” agreement in which the supplier guarantees that:

  • the viewer has been tested for medical use against all possible patient risk,
  • the end user receives regular updates on new features and bug fixes,
  • the end user can be informed of any bug in the medical device.