Median filter and data types

Dear all,
I tried to applied the Median filter and got an error message I can not interprete:
Starting from unstructured polygonal data, I the GenerateNormalSurface and ExtractComponent filter, I create a scalar data array of type float. By using the ResampleToImage filter, I further create a number of structured points that should be later on the grid of the output data. If I now apply the Median filter on the grid points and select the previously generated input array data, I get the error message:

input data type 10, must match out ScalarType 5

If I looked it up correctly, data type 10 is float (=my input data) and 5 is unsigned integer. Does that mean that only unsigned integers can be used as input data for the Median filter ? Do I need to change the output data type to make the filter working properly and if so, where can I change it ?

Kind regards,