Summary:
An itk UnaryImageFilter that computes the modulus of an image.

Evidence:
The figures in the paper illustrate the technique. A test is also provided with both input and output images.

Open Science:
All the code is present.

Reproducibility:
I downloaded the code. It compiled on both Visual Studio 7 and Borland.
I had to edit the CMakeLists.txt file to add ${EXECUTABLE_OUTPUT_PATH} to the ADD_TEST command so that I could run the tests with ctest.

ADD_TEST(Modulus ${EXECUTABLE_OUTPUT_PATH}/modulus ${CMAKE_SOURCE_DIR}/Spots.png out.png distance.png)

ADD_TEST(CompareImage ${EXECUTABLE_OUTPUT_PATH}/ImageCompare out.png ${CMAKE_SOURCE_DIR}/modulus.png)

Use of Open Source Software:
The author used CMake and itk.

Open Source Contributions:
All source and test code was provided.

Code Quality:
Programming style conforms to itk style. Name of class and methods are acceptable. A PrintSelf method is provided.

Suggestions for future work:
Before adding to itk, the operator== and operator!= methods should be added to the Functor. This corresponds to recent changes in itk. Also, the test should be modified to use the itk testing framework before adding to itk. This work can be done by the itk Shepard for this code.

Summary:
Unary functor filter to perform the modulus operator per pixel.


Use of Open Source Software:
This is subclass of UnaryFunctorImageFilter

Code Quality:
Visual inspection of the code looks fine.


Suggestions for future work:
Should probably use the ConceptChecking facilities to ensure the input image type is integral.