1. A high-quality content generation system comprising: a feature extractor that extracts features of contents from a plurality of the contents; a content grouping unit that collates the features of a plurality of the contents extracted by said feature extractor with each other, groups the identical contents and the derived contents produced by using the above identical contents to be included in said plurality of the contents, and calculates identical/derived content grouping information; and a high-quality content generator that selects the contents to be grouped with said identical/derived content grouping information from among said plurality of the contents, and generates the contents of which a quality is more excellent by employing the selected contents.