Creating and Detecting Doctored and Virtual Images: Implications to The Child Pornography Prevention Act

The 1996 Child Pornography Prevention Act (CPPA) extended the existing federal criminal laws against child pornography to include certain types of “virtual porn”. In 2002, the United States Supreme Court found that portions of the CPPA, being overly broad and restrictive, violated First Amendment rights. The Court ruled that images containing an actual minor or portions of a minor are not protected, while computer generated images depicting a fictitious “computer generated” minor are constitutionally protected. In this report I outline various forms of digital tampering, placing them in the context of this recent ruling. I also review computational techniques for detecting doctored and virtual (computer generated) images. Hany Farid, 6211 Sudikoff Lab, Computer Science Department, Dartmouth College, Hanover, NH 03755 USA (email: [email protected]; tel/fax: 603.646.2761/603.646.1672). This work was supported by an Alfred P. Sloan Fellowship, a National Science Foundation CAREER Award (IIS-99-83806), a departmental National Science Foundation Infrastructure Grant (EIA-98-02068), and under Award No. 2000-DT-CS-K001 from the Office for Domestic Preparedness, U.S. Department of Homeland Security (points of view in this document are those of the author and do not necessarily represent the official position of the U.S. Department of Homeland Security).