The first comprehensive and detailed presentation of techniques for authenticating digital images.
Photographs have been doctored since photography was invented. Dictators have erased people from photographs and from history. Politicians have manipulated photos for short-term political gain. Altering photographs in the predigital era required time-consuming darkroom work. Today, powerful and low-cost digital technology makes it relatively easy to alter digital images, and the resulting fakes are difficult to detect. The field of photo forensics—pioneered in Hany Farid's lab at Dartmouth College—restores some trust to photography. In this book, Farid describes techniques that can be used to authenticate photos. He provides the intuition and background as well as the mathematical and algorithmic details needed to understand, implement, and utilize a variety of photo forensic techniques.
Farid traces the entire imaging pipeline. He begins with the physics and geometry of the interaction of light with the physical world, proceeds through the way light passes through a camera lens, the conversion of light to pixel values in the electronic sensor, the packaging of the pixel values into a digital image file, and the pixel-level artifacts introduced by photo-editing software. Modeling the path of light during image creation reveals physical, geometric, and statistical regularities that are disrupted during the creation of a fake. Various forensic techniques exploit these irregularities to detect traces of tampering. A chapter of case studies examines the authenticity of viral video and famously questionable photographs including “Golden Eagle Snatches Kid” and the Lee Harvey Oswald backyard photo.
Hardcover$75.00 S | £58.00 ISBN: 9780262035347 336 pp. | 9 in x 8 in 207 color photos, 74 halftones
Photo Forensics [is] likely to become the bible of the field.
Hany Farid is one of the world's foremost experts in image forensics, having authored several key algorithms for detecting visual forgeries. The book offers a comprehensive technical introduction to this increasingly important field.
Alexei A. Efros
Associate Professor, Department of Electrical Engineering and Computer Sciences, University of California, Berkeley
Hany Farid provides new insights and intuitive explanations about everything you may want to know about image forensics. The combined use of physical and geometrical model, mathematical analysis, and pseudocode samples is beautiful. A great reference and must-read for every researcher or practitioner in this field.
The Richard Dicker Professor of Telecommunications, Columbia University
Through every step of the imaging process, Hany Farid asks, 'How can we exploit this step to reveal image tampering?' The result is a unique and delightful book, a tour of computational photography by a forgery sleuth. I loved it. Hany Farid, preeminent in this field, offers code, case studies, and advice to help readers find manipulated images.
William T. Freeman
Thomas and Gerd Perkins Professor of Electrical Engineering and Computer Science, MIT; Research Scientist, Google