ImageJ Ops is a framework for reusable image processing operations. Ops extends Java's mantra of "write once, run anywhere" to image processing algorithms.
The central goal is to enable programmers to code an image processing algorithm in the Ops framework, which is then usable as-is from any SciJava-compatible software project, such as ImageJ, CellProfiler, KNIME, OMERO and Alida.
Ops has three major design goals:
- Easy to use and extend. There must be a wealth of easy-to-use image processing operations ("ops"), as well as an easy framework for extending those ops in new directions.
- Powerful and general. An op should be able to consist of any number of typed input and output parameters, operating on arbitrary data structures, including images of N dimensions stored in a myriad of different ways: as files on disk, programmatically generated in memory, or in remote databases. Using the powerful ImgLib2 library achieves this ambitious goal.
- Very fast. Even though ImgLib2 is vastly more general than ImageJ 1.x's data model, that generality should not come at the expense of performance. Otherwise, users must pay a time tax to do the same things they could already do in ImageJ 1.x. The ImageJ Ops framework needs to provide a means to override any general-but-slow op with a faster-but-more-specific alternative, fully transparently to the user.
An op is a function which takes a list of typed inputs, produces a list of typed outputs, and has no side effects.
Tutorials and workshops
- ImageJ Tutorial: Using Ops
- For external developers: adapting your code Ops
- ImageJ Tutorial: Create A New Op
- "ImageJ2 scripts: Parameters + ImageJ Ops" (ImageJ conference 2015) – slides, video 1, video 2
- "The ImageJ Ops Framework: Image processing made easy" (January 2015) – slides
- "Intro to ImageJ Ops - Usage and Development" (November 2015) – slides
Why not implement algorithms as "plain old Java" methods?
The Ops matching framework provides extensibility. Ops are plugins, so any developer can override the behavior of a particular op as needed—e.g., for improved performance of a special case. See "Design goals" above.
- 2014-04-04 - Announcing ImageJ Ops news post