Details of Research Outputs

Recently, unsupervised approaches were introduced to analyze the structure of TV programs, relying on the discovery of repeated elements within a program or across multiple episodes of the same program. These methods can discover key repeating elements, such as jingles and separators, however they cannot infer the entire structure of a program. In this paper, we propose a hierarchical use of grammatical inference to yield a temporal grammar of a program from a collection of episodes, discovering both the vocabulary of the grammar and the temporal organization of the words from the vocabulary. Using a set of basic event detectors and simple filtering techniques to detect repeating elements of interest, a symbolic representation of each episode is derived based on minimal domain knowledge. Grammatical inference based on multiple sequence alignment is then used in a hierarchical manner to provide a temporal grammar of the program at various levels of details. Experimental validation is performed on 3 distinct types of programs on 4 datasets. Qualitative analyses show that the grammars inferred at the different levels of the hierarchy are relevant and can be obtained from a fairly limited number of episodes.