Research Of Watermark Certification Based On The Image Characteristics

In recent years, along with the computer network communications and the rapid development of multimedia technologies, digital media transmission and processing becomes very convenient. However, everything has both positive and negative aspects. Digital media to bring people to the convenience, but also introduced a number of potential risks, they can be easily modified. Therefore, how to protect the integrity of a variety of digital media content and authenticity has become an urgent problem to be sloved. Digital watermarking technology to address these issues provides an effective way. Digital watermarking is a technology to embed specific information into the host digital media. As a new type of digital media copyright protection and content authentication, it has aroused great concern and developed very rapidly in recent years. In which digital watermarking for image content authentication general requirements: both robust and fragile, transparency of perception, sensitivity and location of tamper, blind detection and security.This paper studies the image content authentication technology based on digital watermarking algorithm. Firstly, introduces the research background and significance, research status and basic principles, aggressive behavior analysis and development direction. Then we carried out a systematic analysis and description to the home and abroad research fruit and problems. This paper's research work and related fruits include the following aspects:(1) Proposed a watermark authentication algorithm in DCT domain based on coefficients characteristics. The algorithm embedded the watermark into the other sub-block pseudo-randomly by key, and improved the tamper positioning accuracy by nine neighborhood detection. The algorithm has a high resistance to JPEG lossy compression capacity, tampering with positioning accuracy and security.(2) Proposed DWT domain watermark authentication algorithm based on image edge features. The algorithm carried the color image brightness component to two discrete wavelet decomposition, and extraction the LL2 sub-band image edge features as the watermark by Canny operator, then the watermark embedded into the HL1 and LH1 mid sub-belt, by forcing the two adjacent sub-band the size of the relationship between coefficients to embed watermark information. The algorithm has a good resistance to JPEG 2000 compression and noise, tampered with accurate positioning and security.The watermark authentication algorithm presented in this paper is simplely designed,and is secure and reliable with accurate authentication ability.