1. A method of automatically classifying images in a consumer digital image collection, comprising: (a) generating an event representation of the image collection; (b) computing global time-based features for each event within the hierarchical event representation; (c) computing content-based features for each image in an event within the hierarchical event representation; (d) combining content-based features for each image in an event to generate event-level content-based features; and (e) using time-based features and content-based features for each event to classify an event into one of a pre-determined set of semantic categories.