Information processing system, information processing method, information processing apparatus and control method and control program thereof, and communication terminal and control method and control program thereof

An information processing system, comprising a processor and a memory, which includes:

• a first local feature storing unit configured to store, in association with each other, a search object and m-number of first local features which are respectively constituted by a feature vector of 1 dimension to i dimensions and which are generated for each of m-number of local areas including each of m-number of feature points in an image of the search object;
• a second local feature generating unit configured to extract an n-number of feature points from an image of a video captured by a first imaging unit, and that generates n-number of second local features respectively constituted by a feature vector of 1 dimension to j dimensions for n-number of local areas including each of the n-number of feature points;
• and
• a recognizing unit that is configured to select a smaller number of dimensions among the number of dimensions i of the feature vector of the first local feature and the number of dimensions j of the feature vector of the second local feature, and that recognizes that the search object exists in the image in the video when determining that a prescribed ratio or more of the m-number of first local features constituted by a feature vector up to the selected number of dimensions corresponds to the n-number of second local features constituted by a feature vector up to the selected number of dimensions.