Truthfulness and trustworthiness verification of multimedia objects like audio tracks, digital images and video sequences has or should have a key role in our daily life.

Audio-visual data are nowadays valuable sources of information: due to the diffusion of digital devices able of easily acquiring audio tracks and visual contents, each of us may become an active participant in the production of knowledge; furthermore, internet and social media make this knowledge shared and distributed. We can say that we live in a network of sensors, network of people, network of knowledge.