1. An information processing apparatus for carrying out an information registration process to register preference information of a user for an item determined in advance, said information processing apparatus comprising: image feature quantity extraction means for extracting a feature quantity of a taken object image of a photographing object determined in advance from said object image; an object image feature quantity database for storing a feature quantity of each comparison image as a feature quantity to be compared with said feature quantity of said object image by associating said feature quantity of said comparison image with an image ID assigned to said comparison image; an object image preference information database for storing preference information for each comparison image by associating said preference information with an image ID assigned to said comparison image; matching image detection means for detecting the image ID of a matching image defined as a comparison image having a feature quantity matching said feature quantity of said object image from said feature quantity database; and preference information acquisition means for acquiring preference information associated with said image ID of said matching image from said object image preference information database as said preference information of said user for said item if said image ID of said matching image is detected from said object image feature quantity database and outputting said extracted preference information.