Signal processing device and signal processing method

摘要

A signal processing device includes: a filter processing unit configured to execute noise reduction operations by subjecting sound-collected signals from a sound-collecting unit to filtering processing based on preset filter properties and providing with signal properties for noise reduction; a noise-unreduced signal obtaining unit configured to obtain noise-unreduced signals obtained in a state where noise reduction operations by the filter processing unit are stopped; and a filter property selecting unit configured to obtain a difference between the noise-unreduced signals and noise-reduced signals obtained at the time of executing noise reduction operations with preset filter properties set to the filter processing unit as a candidate filter property, thereby obtaining a noise reduction effect indicator regarding the candidate filter property, and selecting filter properties to be set to the filter processing unit based on the noise reduction effect indicator.