Question Answering from Lecture Videos based on an Automatic Semantic Annotation

摘要

The number of digital lecture video recordings has increased dramatically. The accessibility, usability and the traceabil-ity of their content for students-use is limited. Therefore retrieval of audiovisual lecture recordings is a complex task. Speech recognition is applied to create a tentative and deficient transcription of the video recordings. The imperfect transcription is sufficient to generate semantic metadata serialized in an OWL file. A question answering system based on the automatically generated semantic annotations and a semantic search engine are presented. The annotation process is discussed, evaluated and compared to a perfectly annotated OWL file and, further, to a corrected transcript of the lecture.