Patent ID: 11971906
Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
Field: Computer technology (Electrical engineering)
Classification: CPC G | IPC G

Claim 3:
4. The computer-implemented method of claim 1, the method further comprising:
storing a variable transposed file obtained by removing the feature pair including a first non-zero element of a mean feature vector corresponding to an invariant cluster indicating a cluster in which an object feature vector belonging to the cluster has not changed before and after the assignment from the transposed file; and
determining, for generating an inner product associated with the determined distance, a product of:
the second non-zero feature quantity in the object feature vector in sparse representation, and
a first non-zero feature quantity stored in an array element of an index based on a feature identifier corresponding to the second non-zero feature quantity among array elements in the transposed file or the variable transposed file according to whether the cluster to which the object feature vector in sparse representation belongs is an invariant cluster.