Orthanc project status as of February 2022 - and why we are on OpenCollective
Published on February 4, 2022 by Alain Mazy

Dear Orthanc Community,

As many of you have observed, the activity of Osimis around the Orthanc ecosystem has reduced in Q3 and Q4 2021.  I would like to inform you about the current project situation and tell you about my plans for the future of Orthanc.

First a very quick history of Orthanc and its maintainers:
  • 2011 : Sébastien Jodogne created and developed Orthanc alone while working at the University Hospital of Liège – Belgium (CHUL).
  • 2015 : Together with myself (Alain Mazy) and other stakeholders, Sébastien founded Osimis to provide professional services around or on top of Orthanc, as well as to propose certified products that can be deployed within US/EU hospitals.
  • 2021 : Both Sébastien and I left the Osimis management team. Sébastien became professor at University of Louvain – Belgium (UCLouvain) and I went back to freelancing as a Software Developer.

The situation in February 2022 is as follows:
  • Osimis has decided to reduce its support to Orthanc development and focus on AI integration.  Therefore, I’m willing to find a new sustainability model for the Orthanc eco-system.
  • Sébastien continues to develop Orthanc for research and teaching purposes as part of his work at the University, and to maintain the project according to the mission statement of the Orthanc project: “Share technical knowledge about medical imaging.”
  • I will maintain Orthanc with a focus on general community users like software vendors integrating Orthanc in their apps or users running Orthanc as a small PACS.
  • Osimis is still providing the build/hosting infrastructure for the Orthanc project and is funding me a few days a month to keep the project active from an industrial point of view.
  • The Orthanc IP belongs to CHUL – Osimis – UCLouvain and this will remain.  Although this hinders accepting external contributions, this situation is currently fine for the maintainers. Should the project sustainability require it, the maintainers would have the opportunity to fork the project to make sure it keeps going forward. A fork is annoying for everyone, users and maintainers, so it is best to stay away from it.

Unfortunately, with only a few days funded each month, I do not have enough time to create real new features in Orthanc or to effectively maintain it. For instance, there has not been any new Orthanc releases for the last 5 months because making an official release would almost entirely consume the monthly allocation (note that I’ve spent about 30h to automate part of the release procedures to be able to provide releases faster in the future).

Therefore, I am calling for the community to help fund the Orthanc project and mutualize the development cost between as many backers/sponsors/donators as possible.

If you are a Medical Doctor using Orthanc in your daily activity or a freelancer providing Orthanc support, remember that you have paid for your desk or your printer but, so far, you have probably not paid anything for Orthanc. If you think Orthanc is as important to your business as your desk or your printer, then feel free to become a backer of the Orthanc project on Open Collective.

If you are a small clinic using Orthanc in your daily activity, a software company that is integrating Orthanc in its solution, remember that you have paid for your X-Ray, office coffee machine or cloud infrastructure but, so far, you have probably not paid anything for Orthanc. If you think Orthanc is as important to your business as your X-Ray, your office coffee machine or your cloud infrastructure then feel free to become a sponsor of the Orthanc project on Open Collective.

My first goal in funding is to reach 5.600 EUR a month in order to pay 80h a month to maintainers so as to get back to more regular bug fixes, new features, and community support!

Note that, when contributing financially to a free and open-source project, you are not hiring the maintainers for your own needs. You are invited to suggest new features and request bug fixes, but the maintainers are driving the development and roadmap, trying to accommodate the needs of the whole community.

Now that I’ve covered the funding topic, let’s talk about projects!

Let’s release Orthanc 1.10.0! 

There is a bunch of small improvements waiting to be released:
  • A new Python callback to modify/sanitize instances as they are received,
  • A new Lua callback to filter instances received through C-Store,
  • Some optimizations (memory cache + number of DICOM threads count + zip archive),
  • Support for numpy in the REST API for artificial intelligence,
  • And invisible changes to keep the project up-to-date (e.g upgrade to OpenSSL 3).

Orthanc Explorer 2!

I have started to work on a new Orthanc Explorer Interface. I can only share a simple screenshot now just to show you that there is some work in progress, but I plan to release a first version in the next 4-6 weeks.

Over the last few years, a lot of users have requested small/large improvements in the Orthanc Explorer interface.  So far, Orthanc Explorer has always been considered as a low-level interface for developers and system administrators (cf. FAQ). Now, Orthanc Explorer 2 will be a real User Interface.


Here is a very quick list of “short-term” features that I plan to include in the new Orthanc Explorer:
  • Generally more user-friendly (including responsive interface),
  • Customization (data-displayed, menus),
  • Translations,
  • Improved upload interface.
  • Interface to modify tags and improved control of anonymization

And some “long-term” features:
  • Simple User/role management for standalone Orthanc.
  • User/role management through integration with e.g Keycloak.
  • User interface to configure the parameters of Orthanc.

Apple M1 binaries

I have recently received a request to provide binaries for the Apple M1 processor. To this end, I need to purchase a new Apple M1 computer and update the build procedures. This comes with a cost and I have created a specific Open Collective project to fund this task.  Any users interested in Apple M1 binaries are invited to fund this project directly.



As you can see, the Orthanc project and its associated community are at a turning point. People now realize that free and open-source software is at the core of their businesses, and they realize it is “normal” to participate in the funding of these projects to ensure product quality and security. There are numerous examples of projects that are now fully funded by their community; let’s do this with Orthanc, too!


Alain Mazy