Stone of Orthanc
================

General Information
-------------------

This repository contains the source code of Stone of Orthanc.

Stone of Orthanc is a lightweight, cross-platform C++ framework for
the rendering of medical images. It is a companion toolkit to the main
Orthanc DICOM server. It notably features support for MPR (multiplanar
reconstruction of volume images), PET-CT fusion, and accurate physical
world coordinates.

Stone of Orthanc can take advantage of OpenGL/WebGL to accelerate 2D
rendering using the GPU. 3D operations such as reslicing are done
using CPU.

Stone of Orthanc is compatible with any GUI framework (such as Qt,
wxWidgets, MFC...). The provided sample applications use the SDL
framework.

Very importantly, Stone of Orthanc is compatible with WebAssembly,
which makes it suitable to render medical images in Web applications.

As a library for medical imaging, Stone of Orthanc also comes with
primitives to download, parse and handle DICOM images. These
primitives can use either the REST API of the Orthanc server, or the
DICOMweb protocol. Primitives to deal with radiotherapy or nuclear
medicine studies are available as well (image fusion using layers).

Besides the low-level Stone of Orthanc library, this repository also
contains the Stone Web viewer. The Stone Web viewer is a
fully-featured Web viewer that can be either used as a plugin to
Orthanc, or as a standalone viewer if using DICOMweb.


Comparison
----------

Stone of Orthanc is quite similar to two other well-known toolkits:

* Cornerstone, a client-side JavaScript toolkit to display medical
  images in Web browsers, by Chris Hafey <chafey@gmail.com>:
  https://github.com/chafey/cornerstone

  Contrarily to Cornerstone, Stone of Orthanc is written in C++ and
  can be embedded into native, heavyweight applications.

* VTK, a C++ toolkit for scientific visualization, by Kitware:
  http://www.vtk.org/

  Contrarily to VTK, Stone of Orthanc is much more simple, and only
  uses the GPU for 2D rendering.


Dependencies
------------

Stone of Orthanc is based upon the following projects:

* Orthanc, a lightweight Vendor Neutral Archive (DICOM server):
  http://www.orthanc-server.com/

* Cairo and pixman, a cross-platform 2D graphics library:
  https://www.cairographics.org/

* Optionally, SDL, a cross-platform multimedia library:
  https://www.libsdl.org/

  On Ubuntu, you would use:

  $ sudo apt-get install -y libcairo-dev libpixman-1-dev libsdl2-dev

* Optionally, Emscripten, the official compiler for WebAssembly:
  https://emscripten.org/


Installation and usage
----------------------

Build instructions and usage details are available as part of the
Orthanc Book:
https://orthanc.uclouvain.be/book/developers/stone.html

Stone of Orthanc comes with several sample applications in the
"Applications/Samples" folder. Please check the
"Applications/Samples/README.md" file for information on the samples
building and running procedure.

The source code of the Stone Web viewer is located in folder
"Applications/StoneWebViewer".


Technical information
---------------------

- For situations where OpenGL is not available, Stone of Orthanc comes
  bundled with its own software-based rendering engine (based upon
  cairo and pixman). This engine will use CPU hardware acceleration if
  available (notably SSE2, SSSE3, and NEON instruction sets), but not
  the GPU. This makes Stone a highly versatile framework that can run
  even on low-performance platforms.

- Stone of Orthanc is compatible with desktop software, with native
  mobile apps and with Web applications. To achieve this
  compatibility, the rendering loop of Stone of Orthanc is
  single-threaded, and abstracts network transfers and other
  asynchronous events thanks to a so-called "Oracle". The Oracle is
  the place where architecture-specific operations/computations can
  take place (for instance, multi-threading).


Contributing
------------

Instructions for contributing to the Orthanc project are included in
the Orthanc Book:
https://orthanc.uclouvain.be/book/developers/repositories.html


Licensing
---------

Stone of Orthanc is licensed under the AGPLv3+ license.

The files in the "./OrthancStone/Sources/" sub-directory are licensed
under the LGPLv3+ (Lesser GPL). The related COPYING file can be found
in "./OrthancStone/".

We also kindly ask scientific works and clinical studies that make use
of Orthanc to cite Orthanc in their associated publications.
Similarly, we ask open-source and closed-source products that make use
of Orthanc to warn us about this use. You can cite our work on the
Stone of Orthanc using the two following BibTeX entries:

@Article{Jodogne2018,
 title = {The Orthanc Ecosystem for Medical Imaging},
 author = {Jodogne, S{\'e}bastien},
 journal = {Journal of Digital Imaging},
 volume = {31},
 number = {3},
 pages = {341-352},
 issn = {1618-727X},
 doi = {10.1007/s10278-018-0082-y},
 publisher = {Springer Science and Business Media LLC},
 year = {2018},
 url = {https://doi.org/10.1007/s10278-018-0082-y}
}

@Article{Jodogne2023,
 title = {On the Use of WebAssembly for Rendering and Segmenting Medical Images},
 author = {Jodogne, S{\'e}bastien},
 journal = {Biomedical Engineering Systems and Technologies},
 volume = {1814},
 number = {1},
 pages = {393-414},
 issn = {1865-0937},
 doi = {10.1007/978-3-031-38854-5_20},
 year = {2023},
 url = {http://hdl.handle.net/2078.1/277125}
}