  Testing software is often costly due to the need of mass-producing test cases
and providing a test oracle for it. This is often referred to as the oracle
problem. One method that has been proposed in order to alleviate the oracle
problem is metamorphic testing. Metamorphic testing produces new test cases by
altering an existing test case, and uses the metamorphic relation between the
inputs and the outputs of the System Under Test (SUT) to predict the expected
outputs of the produced test cases. Metamorphic testing has often been used for
image processing software, where changes are applied to the image's attributes
to create new test cases with annotations that are the same as the original
image. We refer to this existing method as the image-based metamorphic testing.
In this research, we propose an object-based metamorphic testing and a
composite metamorphic testing which combines different metamorphic testing
approaches to relatively increase test coverage.
