With rapid progress in Internet and digital imaging technology, there are more and more ways to easily create, publish, and distribute images. Considered the first book to focus on the relationship between digital imaging and privacy protection, Visual Cryptography and Secret Image Sharing is a complete introduction to novel security methods and sharing-control mechanisms used to protect against unauthorized data access and secure dissemination of sensitive information.Image data protection and image-based authentication techniques offer efficient solutions for controlling how private data and images are made available only to select people. Essential to the design of systems used to manage images that contain sensitive datasuch as medical records, financial transactions, and electronic voting systemsthe methods presented in this book are useful to counter traditional encryption techniques, which do not scale well and are less efficient when applied directly to image files.An exploration of the most prominent topics in digital imaging security, this book discusses:Potential for sharing multiple secretsVisual cryptography schemes based either on the probabilistic reconstruction of the secret image, or on different logical operations for combining shared imagesInclusion of pictures in the distributed sharesContrast enhancement techniquesColor-image visual cryptographyCheating preventionAlignment problems for image sharesSteganography and authenticationIn the continually evolving world of secure image sharing, a growing number of people are becoming involved as new applications and business models are being developed all the time. This contributed volume gives academicians, researchers, and professionals the insight of well-known experts on key concepts, issues, trends, and technologies in this emerging field"-- "Preface Secure digital imaging is an important research area combining methods and techniques coming from cryptography and image processing. Visual cryptography and in general secret image sharing techniques enable distributing sensitive visual materials to involved participants through public communication channels, as the generated secure images do not reveal any information if they are not combined in the prescribed way. In visual cryptography, the decoding process is performed directly by the human eyes, while in general, the shared images need some processing to reconstruct the secret image. The increasing number of possibilities to create, publish, and distribute images calls for novel protection methods, o ering new sharing and access control mechanisms for the information contained in the published images. Secure image sharing techniques overcome the traditional cryptographic approach, providing new solutions for the development of new and secure imaging applications. Since both digital imaging and privacy protection are two research themes that involve a continuously growing number of people and applications, the book focuses on secure image sharing techniques, o ering an interesting reference point for studying and developing solutions needed in such areas. This book aims to ll the existing literature gap, providing a valid guide for professional people and/​or researchers interested in such elds of research. It provides a scienti cally and scholarly sound treatment of state-of-the-art techniques to students, researchers, academics, and practitioners who are interested or involved in the study, research, use, design, and development of image sharing techniques