Challenges in Audio Processing of Terrorist-Related Data.

Much information in multimedia data related to terrorist activity can be extracted from the audio content. Our work in ongoing projects aims to provide a complete description of the audio portion of multimedia documents. The information that can be extracted can be derived from diarization, classification of acoustic events, language and speaker segmentation and clustering, as well as automatic transcription of the speech portions. An important consideration is ensuring that the audio processing technologies are well suited to the types of data of interest to the law enforcement agencies. While language identification and speech recognition may be considered as ’mature technologies’, our experience is that even state-of-the-art systems require customisation and enhancements to address the challenges of terrorist-related audio documents.