A New Trade System Of Products Based On Asymmetric Double Digital Watermarking

With the development of network technology, the method of use and dissemination of multimedia products has undergone a fundamental change, digital products can be seen everywhere, but digital piracy, copyright disputes and other issues comes on its heels, as an important method for digital copyright protection and piracy detection, digital watermarking technology was born. The digital watermark was first proposed in the1990s, after decades of development, this technology has benn improved increasingly, a variety of method of spatial domain and transform domain have been proposed and perfected continually.Digital product transaction on the internet brings a great impact to multimedia copyright on proprietary, regional and practice. The original methods of registration and management are helplessness. On the one hand, due to the lack of information query institutions in recognition of the copyrights of digital products and the disordered of the network market, on the other hand, because of the reliability of contracting parties is unwarrantably, the copyright of lots of digital products is out of or different to protection that greatly restrains the new development of the multimedia industry and the culture industry. In a word.establishing a complete set of digital trading system to guarantee the legitimate rights of the contracting parties become an urgent problem.Digital watermarks often contain proprietary information such as identity mark, the transaction time, the serial number and so on, and it can be perceived when embedded into digital products, in addition, watermark with information of buyers is allowed to be embedded before sell to achieve the tracking of the source of illegal copies. Using the advantage of digital watermarking technology in the protection of multimedia products and combining with the advantages and disadvantages of the proposed trading system, this paper proposes a new digital product trading system based on asymmetric double watermark technology,the program provides the responsibilities and requirements of contracting parties and also the watermark certification center clearly to prevent the watermark be embezzled, and to ensure the equities of the both sides. The main research work and achievements are as follows:1. Do depth analysis on the possible several attacks on existing system, we discussed some deficiencies and vulnerabilities; then improve the basic design requirements for digital watermarking technology, and complete the supervision of the both parties’ right throughout the trading by taking full advantage of the third parties.2. Construct a complete and effective digital product trading scheme based on asymmetric dual digital watermarking technology and RSA encryption technology:First, the asymmetric robust watermark with identity information of distributor and user is embedded into the product to achieve statement of copyright and to resistance to malicious attacks for watermarking; then embed the unique identification information of the commodities into the product using the fragile watermarking technique, when the product is modified maliciously, the third parties can detect the tampering through extract the fragile watermark.3. The digital products of existing trading system maybe faced the problem of geometric attacks which would result in extracting isn’t accurately due to the watermark can’t locate well, the program improve the resistance of geometric attack through an improved template algorithm, and further to ensure that the product with copyright won’t be suffer the geometric attack such as distort or change the size by illegal buyers.4. A digital watermarking protocol which can be applied in multiple transactions is proposed, which made the seller can transmit transaction information and digital products to multiple buyers by multicast, the proposed protocol can prevent the collusion attacks effectively between the buyer or the seller and the third-party in the case of the third party is encryption, as well as the attack of the intermediary. So it can guarantee the legitimate rights of both the sellers and the buyers effectively.5. The feasibility and effectiveness of the proposed program is analyzed by the example of images of product in Taobao mall, the experimental results show that the watermark which represent the owner’s copyright information still can be extracted accurately when the products are facing with common attacks or geometrical attacks. So it can guarantee the legitimate rights of businesses, at the same time it can identify the behavior of inculpation by sellers.