Provided is a signal processing device performing filter processing operations on an input signal using a plurality of filters to generate an output signal, including a filter processing unit configured to perform a filter processing operation on the input signal using a filter and a generating unit configured to generate the output signal by adding a correction value determined on the basis of each sign and each absolute value of each difference between each of filtered output signals obtained by the filter processing operations performed using a plurality of the above mentioned filter processing units and the input signal, to the input signal.