Digital media-such as pictures, movies, and music-have become widely available due to their advantages over analog media. However, copyright infringement, information leaks, and alteration remain problematic with digital content because it can easily be modified, copied, and sent illegally over the Internet.

　Our goal is to establish content security technologies and systems for fair use of digital content. We have developed and continue to develop fundamental content security technologies, such as information hiding and content anonymization, content security systems that provide copyright protection, information leakage protection, and authenticity assurance, and other security measures. Below are example research projects of our laboratory.

Security technologies for overcoming analog-hole problem　Read More >>>

　Technologies for preventing unauthorized copying through encryption are widely used to prevent the disclosure of personal and confidential information and to protect the copyright of pictures and images. However, once digital information has been converted to analog format and shown on a display or a screen, a digital camera can capture the displayed analog information and invalidate the encryption (the analog-hole problem).

　There are already frequent occurrences of copyright infringement in which digital cameras are used for unauthorized copying of footage shown on screens in movie theaters, and copies are then illegally sold or made available on movie distribution sites or as bootleg copies. In Japan alone, losses due to unauthorized copying of films is said to be 18 billion yen a year. There has also been a case in which national secrets were disclosed by an air traffic controller at Haneda Airport who used a digital camera to photograph displays showing flight information, including Air Force One flight plans, and then posted the photographs on his blog.

　In addition, there are concerns about the increasingly high quality of unauthorized images due to continuing improvements in the functions of display devices and photographic equipment. The prevention of unauthorized copying of displays and screens is an essential countermeasure, requiring urgent steps to prevent information disclosure and to protect copyrights.

• Technology to prevent unauthorized copying of screens
• Technology to prevent unauthorized copying of displays

Privacy-enhancing technologies for resolving trade-offs between data anonymity and utility　Read More >>>

• Privacy Visor
• Fingerprinting technologies for anonymizing data
• Privacy in business processes

Information hiding　Read More >>>

• Color picture Watermarking Survivability to Wide Range of Geometrical Transformations
• Maintaining picture quality of color picture watermarking based on human visual system
• Reversible acoustic information hiding for integrity verification