1. A fully-automatic method of producing a set of tags for an input audiovisual file, the set of tags indicating values of a plurality of attributes of an audiovisual work of a defined type represented by said audiovisual file, the method comprising: analyzing properties of the audiovisual work represented by said input audiovisual file and evaluating a set of one or more features characterizing said properties of said audiovisual work; providing an initial estimate of said set of tags by automatically converting said set of features evaluated in the analyzing step to said initial estimate based on first correlations between physical properties of audiovisual works of said defined type and tags applicable to audiovisual works of said defined type; automatically applying, to the tags of said initial estimate, a set of one or more correlation functions defining a correlation among different tags of a set of training examples, to produce a revised tag estimate, said training examples being audiovisual works of said defined type corresponding to manually-tagged audiovisual files; and outputting a final result of the applying step as the set of tags for said input audiovisual file; wherein the correlation-function application step applies said correlation functions selectively to the tags of said initial estimate by applying said correlation functions to tags having a correlation with the physical properties of audiovisual works of said defined type and not applying said correlation functions to tags that are poorly correlated with the physical properties of audiovisual works of said defined type.