1. An information processing apparatus comprising: a musical composition section extracting unit which extracts musical composition sections with tempos which are close to a preset reference tempo based on tempo information indicating a tempo of each section constituting musical compositions; a harmonization level calculating unit which calculates a harmonization degree for a pair of musical composition sections extracted by the musical composition section extracting unit, based on chord progression information indicating chord progression of each section constituting musical compositions; and a harmonization section extracting unit which extracts a pair of sections with a high harmonization degree for the musical compositions calculated by the harmonization level calculating unit from among sections extracted by the musical composition section extracting unit, wherein the harmonization level calculating unit weights the harmonization degree for the musical compositions such that a large value is set to the harmonization degree between musical compositions with a predetermined relationship.