Magnetic ink printing digital watermark (below)

Digital watermark anti-counterfeiting new trick

With the development of digitalization and networks, the infringement, piracy and arbitrary alteration of digital products have become increasingly serious. A technology that helps copyright protection was born, that is digital watermarking.

What is a digital watermark?

The so-called digital watermark is to add some digital information to multimedia data (images, sounds, video signals, etc.) to achieve the authenticity of the document authentication, copyright protection and other functions.

The digital watermarking process is to add certain information that can be used to prove copyright ownership or trace infringing content to protected digital objects (such as still images, video, audio, etc.), and may be the author's serial number, company logo, meaningful text, and the like. It can be used to identify the source, version, original author, owner, publisher, legitimate user's ownership of digital products for documents, images or music products. They are hidden as a kind of invisible data in the original image to achieve the purpose of protecting all copyright without harming the subjective quality and integrity of the image. The water-saturated image can maintain the original image's image format and other information without affecting the normal information. Copy and handle.

In terms of subjective quality, the difference between the two images is so subtle that they cannot be detected with the naked eye. Only through a specific decoder can the hidden information be presented from it.

How to protect the copyright of digital products

Digital watermarks protect the ownership of digital images, video, sound, and more. When using Photoshop 7.0 to edit images, digital watermark filters can be used to protect their own work, the general use of the filter is Digimarc.

The Digimarc filter consists of two components, namely Embed Watermark (embedded digital watermarking component) and Read Watermark (reading digital watermarking component). Their main role is to add copyright information to Photoshop format images. When the user uses this kind of filter-processed image, it will remind the user that the image is protected by a digital watermark.

The digital watermark is added to the image in the form of a streaky pattern, which does not affect the image characteristics, but it can shield a variety of image operations such as color correction, filter effects, and printing.

Using an embedded digital watermark filter

Use Embed Watermark filters to add information to the image. When other users use the image, they will be reminded that the image has been embedded in the image using Digimarc Picture Marc technology. This means that the copyright has been protected. . This watermark effect is added in the form of streaks, which are not easily detectable by the eyes and can be permanently stored on a computer or in printed publications. The Embed Watermark filter can only be used with CMYK, RGB, Lab or Grayscale images.

Based on the protection of copyright, the watermark effect cannot be cancelled. In other words, images that have been watermarked by Digimarc cannot be watermarked, otherwise there is no copyright at all. Therefore, before embedding a watermark, it is a good idea to make a copy to back up as an accessory. In addition, the following must be considered before embedding the watermark in the image: image color change, image pixel number, workflow, etc. Embed Watermark filter is generally used in the final image. Since many editing operations will be limited after embedding the watermark, all the image editing operations must be completed before using this filter.

Digimarc filters are supplied by Digimarc. To embed a digital watermark in an image, you must first register with Digimarc, get a Creator ID, and then insert this ID number along with the copyright information (such as creating year and time) into the image.

First execute the Filter |Digimarc| Embed Watermark filter, click the Personalize button, open the Embed Creator ID dialog box, and then click the Register button to find the Digimarc Web page via the Internet, and apply for a user-specific license number (ID Number ). The returned page will provide a PIN (two digits) and an ID number. The PIN code you want to keep well, the ID number is public, others read your number. At the same time, this ID number is your password for entering Digimarc.com's personal information maintenance. Then enter the ID number in the Creator ID text box and click the "OK" button to return to the Embed Watermark dialog. If the user has created an ID number, the “Personalize” button of the Embed Watermark dialog becomes a Change button, allowing the user to enter a new Creator ID. After the ID is obtained, you can type the annual logo of the image creation in the Copyright Year(s) text box in the Copyright Information option group to embed it as a watermark.

Of course, to truly embody the role of digital watermark protection, we need to set the following attributes of the image according to our needs in the Image Attributes option group:

1. Restricted Use: Restrict other users' right to use the image, that is, the copyright is already in place.

2. Do Not Copy: When selected, copying of the image file is not allowed.

3. Adult Content: After selection, the watermark will indicate the inclusion of restricted content to limit minors from viewing restricted content.

4. Target Output: The Target Output option determines the type of watermark that this image is written in. Print is included for printing. Its watermark has the strongest effect and has the greatest impact on the image. After the photo is printed, it passes through the scan. Shooting and other imaging methods will weigh

Newly imported into the computer, Digimarc can also be used to read the watermark.

5. Watermark Durability: Set the value 1-4. The larger the value, the greater the effect on the image quality, but the less likely it is to be damaged. Levels 1-2 can be used for high-quality print output, while grades 3-4 are mostly used for multimedia and online publishing. Although the image quality is large, it is not easy to see the difference on the screen.

After completing the above procedure, click the "OK" button to end the operation of embedding the digital watermark effect.

Use reading digital watermark filter

Read Watermark filter is mainly used to read the digital watermark content in the image. When an image contains a digital watermark effect, a (c) symbol appears on the image window title bar and status bar.

To use this filter, just execute the Filter|Digimarc| command. Photoshop analyzes the image content and finds the contained digital watermark data. If you find the ID and related data, you can connect to Digimarc's Web site. , According to the ID number, find the author's contact information and rent (ie rent this image with the right to do) fees.

The original digital watermarking technology was used only to identify digital images and has now been developed to include other forms of digital media, especially sound and video. Recently, sound files have received widespread attention due to the desire of the music industry to implement MP3 digital watermarking schemes. A typical example of such an application is the DVD copy protection system, which adds watermark information to DVD data so that the DVD player can determine the legitimacy and copyability of the DVD data by detecting the watermark information in the DVD data, thereby protecting the manufacturer's Commercial interests.

Digital watermarking opens up a new approach to information security. Its invisible concealment and ability to resist various attacks can achieve the integrity protection and falsification of digital products. It can also be used in digital anti-counterfeiting. Digital watermarking is bound to become one of the core technical measures for copyright protection and authenticity authentication of digital works, and it plays an irreplaceable role in e-commerce transactions.

Source: Guangzhou Printing Network