A Study Of The Combined Technique Of Digital Watermarking

The rapid growth of the information the increasingly technology, development of e-commerce, easy access the to digital media and the increasingly powerful digital media manipulation tools have made media security a very important issue. In recent years, some new concepts of in formation security have been proposed, especially in the application of intellectual property right protection, copyright protection and Tamper-proofing. Information hiding and digital watermarking are new measures of digital media protection, which are processes of embedding hidden messages within digital media such as text, images, video and audio. The hidden messages could be copyright information, user distributor identification number, company logo, personal signature, control bits, or any information considered useful for a specific application. Digital watermarking has recently been proposed as a new mean to provide copyright protection of multimedia data and image authentication.This text mainly studied the current development condition of digital watermarking, a technique of image scrambling, Discrete Cosine Transform, a technique of digital watermarking based on DCT, Discrete Wavelet Transform, and technique of digital watermarking based on DWT. The approach of digital watermarking on both DCT and DWT was realized. This kind of approach adopted to embed the digital watermark information based on various areas. The approach has higher concealment and higher robustness of watermarking.