According to the present invention, there is provided a processing device (10) which includes a sound collection unit (11) that collects an environmental sound outside a vehicle, a filter unit (14) that performs filtering for emphasizing a sound characterizing a current position of the vehicle of which the environmental sound is collected, from the environmental sound collected by the sound collection unit (11), and a processing unit (12) that causes the environmental sound including the filtered sound to be output to the inside of the vehicle.