Digital watermarking technology is the latest information hiding technology in the world. The so-called digital watermarking technology is to embed copyright information such as numbers, serial numbers, text, and image signs into multimedia data to play the role of copyright tracking and copyright protection. In addition, digital watermarking also has important application value in authenticity authentication, covert communication, sign concealment, and electronic identity authentication. The research of digital watermarking technology involves research fields such as informatics, cryptography, mathematics, computer science, pattern recognition, etc., which makes the hidden information more concealed, safe, and also has symmetry and error correction. The research indicates that digital watermarking has huge and broad application prospects, and has aroused widespread concern in academia, industry and the military.
In order to identify the authenticity of banknotes in daily life, people usually face the banknotes against the light source, and they will find that clear image information is displayed in the real banknotes. This is the familiar "watermark". The reason why the watermark technology is adopted is because the watermark has its unique properties: the first watermark is an almost invisible mark, which must be placed in a specific environment to be seen without affecting the use of items; the production and reproduction of the second watermark It is more complicated, requires special processes and materials, and the watermark on the printed matter is difficult to be removed. Therefore, watermarks are often used in important prints such as checks, certificates, passports, and invoices. For a long time, an important method to determine the authenticity of printed matter is to check whether it contains a watermark.
With the advent of the digital age, the multimedia digital world is rich and colorful, and digital products affect almost everyone's daily life. How to protect these digital products that are closely related to us, such as copyright protection, information security, data authentication, and access control, etc., is increasingly valued and becomes urgently needed. Drawing on the meaning and function of ordinary watermarks, people adopt similar concepts to protect multimedia data such as digital images and digital music, so the concept of "digital watermarks" has emerged. The so-called "digital watermark" is some digital information added to the multimedia data, for example, the information of the producer will be added to the digital photo, and the information of the movie company will be added to the digital video disc. Similar to the characteristics of ordinary watermarks, digital watermarks are almost invisible in multimedia data (such as digital photos) and are difficult to destroy. Therefore, digital watermarking is very promising in today's computer and Internet era.
What digital watermark can do
The concept and method of digital watermarking were first proposed to protect the copyright of multimedia data. With the development of computers and the Internet, more and more works of art, inventions or ideas are beginning to be expressed in the form of multimedia data, such as photography with digital cameras, watching movies with digital cinema, listening to music with MP3 players, and painting with computers Painting and so on. The multimedia data involved in all activities contains a lot of valuable information. Compared with the hardship the author spends creating these multimedia data, tampering, forgery, copying and illegally publishing original works have become a breeze in the information age. Anyone can easily create a copy of the multimedia data. Compared with the original data, the copied multimedia data will not have any quality loss, that is, it can completely "clone" the multimedia data. Therefore, how to protect the "intellectual property rights" attached to these data is an urgent problem to be solved. Then digital watermarking is just an effective means to solve this kind of "copyright problem". For example, the former painter used the seal or signature to identify the author of the work, so today he can add his name to the work through digital watermarking to complete the copyright identification. Similarly, audiovisual companies can also add company names, logos and other information to published tapes and CDs. In this way, the copyright of the multimedia data is protected by tracking the digital watermark information in the multimedia data.
In addition to the application of copyright protection, digital watermarking technology also has great uses in authenticity verification of documents (printed materials, electronic documents, etc.), such as red-headed documents issued by government departments. , Stamps or steel stamps meet the specifications and standards, the disadvantage is that no matter paper, stamps or steel stamps are easily forged. Especially for seals, although government departments have strict regulations on the management and production of seals, there is still a saying in the society that "one radish engraves one seal". This shows that the traditional method has very imperfections. Using digital watermarking technology can effectively solve this problem. Using digital watermark as an information carrier, some information is added to the red-headed file, so that the file not only has a seal or steel stamp, but also has difficult to detect digital watermark information, thereby greatly increasing the difficulty of forging the file. Adding digital watermark information to a document also means that certain information can be written twice in the document. For example, the name of the passport holder is clearly printed in the passport, or it can be hidden as a digital watermark in the avatar. If someone wants to forge a passport by changing the avatar, it is possible to detect the concealment by scanning the passport The watermark information in the avatar does not match the name printed on the passport, so the forged passport is found.
In addition, digital watermarking is also used for access control and copy control of multimedia data. For example, the secret digital watermark information in the CD data disk can conditionally control who can access the content in the CD disk. At present, DVD has become popular in the domestic electronics market, and many large companies have begun to study how to use digital watermarking systems to improve DVD access and copy control. For example, I hope that the DVD player in the consumer's hands allows unlimited copying of home videos or expired TV programs. The digital watermark added to the home video does not contain any control logo. The digital watermark logo in the TV program is "copy once", " Copy multiple times ", and commercial video programs are marked as" not allowed to copy ", the relevant playback equipment will identify these digital watermark marks and play a corresponding role. This not only guarantees consumers the freedom to copy and exchange programs in private, but also effectively controls commercial infringements. At present, all solutions have been formed. The problem is that the security, effectiveness, and simplicity of this solution need to be further tested, and they cannot be provided to DVD manufacturers and users for the time being.
Digital watermark technology can also be applied to the secure communication of information. Since it is difficult for people to perceive the existence of digital watermark information in multimedia data, some important information can be hidden in ordinary multimedia data during transmission, thereby avoiding eavesdropping and monitoring by third parties. Foreign newspapers reported that terrorist leader bin Laden used publicly released digital watermark technology to hide the instructions given to Al Qaeda in ordinary digital photos through digital watermarks, and then posted them on some websites' BBS. Al Qaeda members agreed according to the agreement The rules extract digital watermark information from digital photos. Compared with ordinary telephone communications, e-mail communications, and encrypted communications, this approach is highly concealed, difficult to monitor, and difficult to detect.
Quadruple Rotors Watch Winder has a built-in smart timer that will wind then rest and repeat the cycle in either clockwise, counter clockwise or bi-directional directions. Quadruple rotors watch winder can hold 4 watches, increased interior space to accommodate large size watches, microfiber cleaning cloth, microfiber protective storage bag, and a matte black storage box. The watch winder will not only wind your automatic watches but also store it as well. Each watch winder is hand made and developed to wind all popular brands of time pieces. This watch winder use Japanese Mabuchi Motor to work, it's very quiet, even if you're sleeping, leaving it in your bedroom won't wake you up. All the above are the characteristics of our watch
Mens Watch Winder,Motion Watch Box,Used Watch Winder,10 Watch Winder
GUANGZHOU T.WING-PAK MFG.CO.,LTD , https://www.twing-pak.com