Hi Bertug,
As you are using image files, you need to use the "Parameter Overrides" section to change the name of the image you are importing with the Image From File block. This will take the place of the input and you can leave the "Inputs" section of the test case empty. See this doc page for more details: https://www.mathworks.com/help/sltest/ug/specify-test-properties-in-the-test-manager.html#bulu9hh
As for determining if your test passed or failed, "Baseline Criteria" is just one way to do it. The best approach will depend on how you assess whether your test passes or not. One option is to do any necessary post processing in the test harness with Simulink blocks, and then compare then expected output with your block output using an Assertion block. Another option is to use a Test Assessment block. This example here should be helpful: https://www.mathworks.com/help/sltest/ug/connecting-blocks-for-verify-statements.html
Hope this helps.
