From entertainment to court decision, from broadcasting to surveillance, and from investigation agencies to smart classes, video applications have already infiltrated into many aspects of our lives. In the past decade, video based industry has flourished at an unparalleled speed. However, as a spin-off of this exciting development, many security issues have inevitably emerged. In video industry, in contrast to the copyright issue, the issue of video content integrity concerns not only the content provider, but also the content receiver. As compared to other applications such as text and audio, the video applications have greater popularity due to its redundancy and credibility of information. However, this credibility is losing its ground to video counterfeits due to the rapid development in digital technology, which makes malicious attacks on videos more possible than ever. In this book, two secure, robust and local-features based intelligent video authentication algorithms, aiming at different video applications have been proposed and discussed. In general, both the algorithms are useful for forensic investigation of digital videos and can be employed in Investigation Agencies.