1. An image processing apparatus, comprising: a processor configured to: acquire a plurality of images from terminal devices of a plurality of users through a network for a predetermined period; analyze contents of each of the plurality of images; calculate an analysis evaluation value of each of the images based on an analysis result of each of the images; acquire evaluation information, which indicates evaluation for each of the images that is given by the plurality of users, from the terminal devices of the plurality of users through the network for the predetermined period; and form one or more groups, each of which includes a plurality of similar images, by specifying the plurality of similar images, among the plurality of images, based on the analysis result of each of the images after the predetermined period has passed, wherein the processor calculates an overall evaluation value for each of the images included in the group by adding a value to an analysis evaluation value of each of the images included in the group based on evaluation information, which indicates high evaluation given to the images in the group, for each of the groups, and wherein the processor adds a weighting, which increases as a number of pieces of evaluation information indicating the high evaluation for each of the plurality of similar images increases, to the analysis evaluation value of at least one of the similar images in the group.