7. A computer-implemented method for content recognition, search, and retrieval in visual data, the method comprising an act of causing a processor to perform operations of: receiving unlabeled visual data as an input; extracting a set of activity-agnostic content descriptors from the unlabeled visual data with a hierarchical content descriptor module having a plurality of levels, resulting in a set of generated activity-agnostic content descriptors, wherein each level of the hierarchical content descriptor module generates a distinct set of activity-agnostic content descriptors; indexing the generated activity-agnostic content descriptors with a hierarchical content indexing module having a plurality of levels corresponding to the plurality of levels of the hierarchical content descriptor module, resulting in a set of indexed content descriptors; wherein each level of the content indexing module comprises a distinct set of indexed content descriptors from a corresponding level in the hierarchical content descriptor module; storing the unlabeled visual data, the set of generated activity-agnostic content descriptors, and the set of indexed content descriptors in a storage module; searching the storage module and retrieving visual data containing a content of interest based on a user query; refining the user query based on feature weighting; and presenting the visual data containing the content of interest to the user.
7. A computer-implemented method for content recognition, search, and retrieval in visual data, the method comprising an act of causing a processor to perform operations of: receiving unlabeled visual data as an input; extracting a set of activity-agnostic content descriptors from the unlabeled visual data with a hierarchical content descriptor module having a plurality of levels, resulting in a set of generated activity-agnostic content descriptors, wherein each level of the hierarchical content descriptor module generates a distinct set of activity-agnostic content descriptors; indexing the generated activity-agnostic content descriptors with a hierarchical content indexing module having a plurality of levels corresponding to the plurality of levels of the hierarchical content descriptor module, resulting in a set of indexed content descriptors; wherein each level of the content indexing module comprises a distinct set of indexed content descriptors from a corresponding level in the hierarchical content descriptor module; storing the unlabeled visual data, the set of generated activity-agnostic content descriptors, and the set of indexed content descriptors in a storage module; searching the storage module and retrieving visual data containing a content of interest based on a user query; refining the user query based on feature weighting; and presenting the visual data containing the content of interest to the user. 8. The method for content recognition, search, and retrieval in visual data as set forth in claim 7 , wherein the query is an unlabeled video clip containing a content of interest.