1. An information processing system, comprising: a first local feature storing unit which stores a piece of merchandise and m-number of first local feature which are respectively 1-dimensional to i-dimensional feature vectors and which are generated for each of m-number of local areas including each of m-number of feature points of an image of the merchandise after associating the piece of merchandise and m-number of first local feature with each other; an imaging unit; a second local feature generating unit which extracts n-number of feature points from an image on a video captured by the imaging unit and which generates n-number of second local feature which are respectively 1-dimensional to j-dimensional feature vectors for n-number of local areas including each of the n-number of feature points; and a recognizing unit which selects a smaller number of dimensions among the number of dimensions i of the feature vectors of the first local feature and the number of dimensions j of the feature vectors of the second local feature, and recognizes that the merchandise exists in the image on the video when determination is made that a prescribed proportion or more of the m-number of first local feature which are feature vectors up to the selected number of dimensions correspond to the n-number of second local feature which are feature vectors up to the selected number of dimensions.