1. An information processing device comprising: circuitry configured to recognize a predetermined part of a body of a person from an input image including the person; evaluate a difference between a recognized input part and a reference part serving as a basis; and notify information relating to the difference of the input part from the reference part based on an evaluation result by superimposing an image of the input part and one of a guide line indicating movement of the input part toward the reference part and an image of the reference part, and displaying a resulting image, wherein the input image is a moving image, the circuitry compares time length of an input action specified by one of an angle and a position of a joint in the input part, obtained in a time-series manner, with time length of a reference action specified by one of an angle and a position of the joint in the reference part, and evaluates a difference of speed of the input action from the reference action, and the circuitry displays information relating to the evaluated difference of the speed.