Development and application of the hottest digital

Development and application of digital watermarking technology (I)

1 Introduction

in recent years, with the rapid increase of Internet users, the circulation of multimedia information is also popular. Because it is easy to play back images and sounds with computers, most users can send and receive multimedia information after they have their own pages

it can be said that this indicates the possibility of a new business using Internet. On the other hand, because the duplication of digital information will not cause the deterioration of information quality, illegal duplication and tampering and other infringement problems also occur from time to time. As a means to solve this kind of infringement problem, digital watermarking technology has attracted much attention in issuing detection reports. This paper mainly introduces the development status, standard formulation and application examples of digital watermarking technology

2 what is digital watermarking technology?

digital watermarking technology refers to a technology that uses the redundancy of media such as image and sound to reuse other information imperceptibly in the information content. In other words, embed some other information in multimedia information such as images and sounds, and hide it. The function of digital watermarking

technology is to embed copyright information or user information in the circulating information content, so as to protect the copyright of information content, but not weaken the advantages of digital information

digital watermarking technology has three characteristics. One is that the embedded watermark cannot be removed. Even after the information content is compressed, filtered or otherwise processed, the watermark remains in the information content. If someone wants to forcibly remove it, the overall quality of the information content is expected to perform well and will deteriorate, so that it cannot be applied. Second, it is difficult for ordinary people to determine where the watermark is embedded in the information content. When they watch images or listen to music, it is difficult for them to find watermarks. The last feature is that the information content will not change due to the addition of watermark, which is different from ordinary scrambling or encryption. The above characteristics of digital watermarking technology are very suitable for the copyright protection of information content, so the development of copyright protection system using digital watermarking is gradually booming

3 two ways of copyright protection

in the copyright protection system using digital watermarking technology, it is large but does not affect users' use. It can be divided into the following two ways:

(1) the way of embedding copyright information

if the information content is broadcast by satellite or ground waves, or the information content is distributed by CD, DVD and other storage media, Then we can consider embedding copyright information and using rule information in the information content in advance. The use rule information mentioned here refers to the marking information used to manage the input/output of data on the player and video recorder. The content provider entrusts the copyright management center to carry out digital watermark processing in its information content, so as to remind users of copyright and restrict the use of received information

(2) method of embedding user information

if the information content is sent on Internet or a service like VOD, the content provider may embed the user's ID in the information content and send the information content at the same time after receiving the user's request. In addition, even in the above-mentioned digital broadcasting and information content supply services using storage media, it can be considered to embed the serial number (number) of the user's receiver and playback machine when using the content. In this way, even if piracy occurs, its source can be investigated, so as to receive the effect of restraining illegal replication

Table 1 lists several requirements for the above copyright protection system