What is this product?

The Digital Video Authenticator (DVA) is a device for verifying the "data integrity" of digital video. Digital video is quite easy to edit. Before a digital video can be used as evidence in a court of law, prosecutors must have a method of proving that it has not been modified or edited. Because there has been no accepted technique for proving that a digital video has not been altered, courts have been forced to rely on analog video systems.

The DVA system can be used to prove that a digital video has not been modified since it was first recorded. The software is implemented on a commercial laptop or on a palmtop that works with any standards-compliant digital camcorder. While the camcorder is recording, the system simultaneously generates and records three digital signatures per frame—one each for the video and audio and one for the time stamp of the frame. The signatures are encrypted via public key cryptography, and they make it possible to prove that the original video and the video offered as evidence in court are identical.

Engineering prototype of the Digital Video Authenticator with palmtop and standards-compliant camcorder.

© 2003 The Johns Hopkins University