1. An information processing apparatus comprising: learning means for performing Adaptive Boosting Error Correcting Output Coding learning using image feature values of a plurality of sample images each being assigned a class label to generate a multi-class classifier configured to output a multi-dimensional score vector corresponding to an input image; registration means for inputting a register image to the multi-class classifier, and registering a multi-dimensional score vector corresponding to the input register image in association with identification information about the register image; and determination means for inputting an identification image to be identified to the multi-class classifier, and determining a similarity between a multi-dimensional score vector corresponding to the input identification image and the registered multi-dimensional score vector corresponding to the register image, wherein the learning means performs Adaptive Boosting Error Correcting Output Coding learning using image feature values of a plurality of sample images each being assigned one of K class labels to generate an entire-image multi-class classifier configured to output a K-dimensional score vector corresponding to an input image, and performs independent Adaptive Boosting Error Correcting Output Coding learning using an image feature value of each of segment images obtained by dividing each of the sample images into M parts to generate M part-based multi-class classifiers each configured to output a K-dimensional score vector corresponding to the input image.