Unfortunately, it doesn't look like you can generate code from this class. Perhaps you can separate out the call to the filter into a separate function and generate a MEX-file from the rest of your code?
PS: For a function unsupported for code-generation, I would have recommended declaring it as |coder.extrinsic>, but according to the documentation, "You cannot use coder.extrinsic to declare a class or method as extrinsic."
