Patent ID: 7478104

Claim:
An information processing apparatus for clustering a plurality of pieces of data in clusters corresponding respectively to nodes on layers in a tree structure by assigning each of said pieces of data to a leaf node of said tree structure, said information processing apparatus comprising: metadata acquisition means for acquiring metadata of said pieces of data; and tree-structure processing means for finding a first distance and a second distance on the basis of said metadata and adding a new node to said tree structure on the basis of said first and second distances as a node having an attention node, which is assigned to attention data placed at an attention-receiving position in an array of said pieces of data arranged on the basis of said metadata of said pieces of data, as a child node where, said first distance is a distance based on a predetermined distance scale as the distance between two adjacent pieces of data selected among pieces of data pertaining to a cluster selected among clusters corresponding to nodes of said tree structure as a cluster adjacent to said attention data placed at said attention-receiving position, and said second distance is a distance based on said predetermined distance scale as the distance between said attention data and a piece of data selected among said pieces of data pertaining to said cluster adjacent to said attention data as a piece of data adjacent to said attention data.