1. An information processing device that is connected to a projecting device that projects an annotation image input from an external terminal onto a projection area including an object and a background, and is connected to an image capture device that captures an image of the projection area including the object and the background, the information processing device comprising: a detecting unit that detects movement of the object from an image captured by the image capture device; an extracting unit that extracts a changed region that is caused in the captured image by the movement of the object; and a processing unit that performs processing on at least one of the captured image and the annotation image, when the annotation image exists in the changed region.