IMAGE PROCESSING DEVICE, IMAGE PROCESSING SYSTEM, COMPUTER CONTROL METHOD, AND INFORMATION STORAGE MEDIUM

To enable a prompt switching operation by a user. An image processing device connected to an image capturing section has a process execution section for executing any of a plurality of processes, obtains area specification data for specifying an area where the user is shown in the image, based on a difference between the images sequentially captured by the image capturing section images, and switches a process to be carried out by the process execution section, depending on the position of an edge of the area specified by the area specification data obtained.