Cryptanalyzing Some Multimedia Encryption Schemes

Low efficiency of the traditional text encryption schemes to protect the multimedia data makes designing secure and efficient multimedia encryption schemes become urgent. Many specific multimedia encryption schemes were designed by adopting some related nonlinear theories. However, shortage of security scrutiny of multimedia encryption schemes frustrated progress of their security level. As a digital image is a typical form of multimedia data and it can show performance of an encryption scheme effectively, many multimedia (chaos-based) encryption schemes adopt images as the encryption object. This book focuses on evaluating the security of six image schemes against some common attack methods, such as brute-force attack, known/chosen-plaintext attack and differential attack. Both rigorous theoretical analyses and detailed experimental results are provided to support the security defects. In addition, some general recommendations for designing secure multimedia encryption scheme are concluded. The cryptanalysis work presented in this book will help cryptanalysts and designers of multimedia encryption schemes understand how to analyze the security of an encryption scheme.