TW201732732A - Method of deploying heterogeneous anti-counterfeit mesh points and virtual grey balance based on image segmentation for utilizing different high-frequency and low-frequency mesh point distributions in a colored image of a valuable security to facilitate authenticity verification - Google Patents

Abstract

The present invention relates to a method of deploying heterogeneous anti-counterfeit mesh points and virtual grey balance based on image segmentation. The method mainly utilizes different high-frequency and low-frequency mesh point distributions in a colored image of a valuable security to facilitate authenticity verification by a naked-eye or an image captured by a mobile phone camera. The method segments an image into different zones, and deploys heterogeneous mesh points of different shapes, line counts and frequencies in each zone, so as to achieve an anti-counterfeit function. Furthermore, the method utilizes virtual grey balance, refers to the shapes and line counts of the mesh points in different zones of the image, appoints a mesh point condition or a virtual way as a reference of grey balance, and modifies the mesh points in different images to make them close to a virtual curve, so as to adjust a problem of mesh point color inconsistency caused by high-contrast frequency differences, and thereby further harmonizing a colored pattern to achieve excellent practical value.

Description

Method for arranging heterogeneous anti-counterfeiting dots and virtual gray balance by image partitioning

The invention provides a method for arranging heterogeneous anti-counterfeit dots and virtual gray balance by image partitioning, mainly by partitioning the color images of the securities, and adopting different high-frequency and low-frequency dot distributions to facilitate the image capturing of the naked eye or the mobile phone camera. Judging its authenticity, in order to make the color consistency of each area, the virtual gray balance is used to adjust the heterogeneous dot to overcome the problem of different colors caused by different dot shapes and lines.

Since securities, such as stamps, banknotes, stocks, gift certificates, tickets, etc., have their economic and exchange value, anti-counterfeiting designs are added to the production to avoid being copied and suffered losses. The general anti-counterfeiting method is to use the same dot shape and a line number for copying when the color image of the securities is produced in the Ripping process. Therefore, the printed matter is also a single dot structure, so the forgery It is also easy to copy and print into a single dot shape and line number of prints, which is difficult for ordinary people to detect the difference between authenticity and authenticity.

It is known that the Republic of China invented No. I298231, the method of mixed dot digital watermarking, Patent B, has improved, and the technology used is to make the anti-counterfeit graphic into an invisible technology, and it is difficult to form a fairly shallow AM and FM dot. The hidden information that is perceived is difficult to be copied and achieves a certain degree of anti-counterfeiting. However, when it is judged by securities, it needs the assistance of other instruments, and it must be experienced by professionals with considerable experience. Discrimination of the average person It is obviously insufficient to understand convenience. The invention is based on the above-mentioned known technical premise, and then improved design, and proposes an anti-counterfeiting method for arranging heterogeneous dots by image partitioning, and can arrange high-frequency and low-frequency dot shapes and lines with different contrasts in different regions of the color image. The number can be provided by the general public to obtain the image by the naked eye or the mobile phone camera, and the authenticity of the securities can be easily judged, and the convenience and recognition of the forensicness can be improved to obtain the intended effect.

The invention relates to a method for arranging heterogeneous anti-counterfeit dots and virtual gray balance by image partitioning, which mainly adopts different high-frequency and low-frequency dot distributions in color images of securities, which can facilitate image taking by naked eyes or mobile phone cameras. It can be judged by the fact that the different areas of the image are demarcated, and the heterogeneous dots of different shapes, lines and frequencies are arranged in each area to achieve the anti-counterfeiting function, and the virtual gray balance is adopted, and the different areas in the image are referenced. The shape and number of dots, specify a kind of dot condition or the basis of gray balance in a virtual way, and then adjust the dot correction value in other different images to a virtual curve, which can adjust the color difference of the dot caused by the large difference of the contrast. To make the color pattern more harmonious.

Fig. 1 is a schematic view showing the arrangement of heterogeneous dots in the image partitioning of the present invention.

Figure 2: Schematic diagram of the invention using Fourier transforms of dots of different frequencies and shapes.

Figure 3 is a flow chart of an embodiment of the present invention.

Figure 4: Schematic diagram of the process of the vector path cutting method of the present invention.

Figure 5: Schematic diagram of the result of the vector path cutting in the present invention.

Figure 6: The present invention uses a heterogeneous dot and a virtual gray balance to adjust the color.

Figure 7: Schematic diagram of the method of the present invention for controlling gray balance to obtain stable color.

Fig. 8 is a schematic view showing the adjustment method of the virtual gray balance of the present invention.

Figure 9: Schematic diagram of the expansion of the dot of the present invention to meet the virtual gray balance.

Figure 10: The present invention completes the image partitioning arrangement of heterogeneous dots and corrects the color of the printed matter.

The invention provides a method for arranging heterogeneous anti-counterfeit dots and virtual gray balance by image partitioning, mainly as shown in the third and sixth figures, wherein the heterogeneous anti-counterfeit dots are arranged firstly, and the gray balance of one of the mesh conditions is used as a reference value. The gray balance correction value of other dot conditions, or the plate correction value of different dot conditions, and then the adjustment of the target value by the virtual gray balance of the dot signals of each zone, and the adjustment into the image partition area to obtain the final Image signals and outlets. The detailed steps are as follows:

1. In the production of color securities, the high-frequency and low-frequency dots are used in the same image. When color images set heterogeneous dots in different blocks, each region is clearly divided. The logical operation of the vector path is used to ensure that there are no discontinuous white or black edges on the boundary. That is, in general commercial printing, when heterogeneous dots are set in different blocks, if the boundary function of Photoshop image processing software is used to process the boundary, there will be a phenomenon of discontinuous white (black) edges (such as Figure 1 (c). As shown in the figure, the method for solving the boundary problem in the present invention is to adopt a vector path logical cutting method at the image partition boundary to obtain a closed partition image. For example, the green path in Figure 4 can be imagined as a die, and the red path will be cut by the green die. The result is shown in Figure 5. The closely visible partition image can be clearly seen to facilitate the different frequency points. Distribution status.

2. Each region can be arranged with different high frequency and low frequency dot shape and line number of heterogeneous dots, such as As shown in Fig. 2, the shape is different frequency and dot, and after conversion into a frequency domain by Fourier, it can be clearly seen that the two high-frequency regions of different densities are located at the central position, which proves the present invention. The technology can be taken by the naked eye or the mobile phone camera, that is, the authenticity of the pattern can be judged.

However, for most of the color prints of securities, such as stamps, in addition to anti-counterfeiting capabilities, color consistency must be maintained. However, when different dot shapes and line numbers appear in the same image, color inconsistencies will occur. The main reason is that according to the Border Zone Theory, when the high-numbered dots are printed on the paper, the periphery of each dot is squeezed and expanded to cause the dot to expand. The dot enlargement indicates the color of the color. It has become deeper. Therefore, it is necessary to solve the problem of inconsistent colors. Another feature of the present invention is a method for adjusting the color consistency of heterogeneous dots by using virtual gray balance. Generally, the colors of thousands of colors on the printed matter are combined by CMYK different dots, and the base is equal by CMY is constructed, and the equivalent CMY can be replaced by K, and the expression is C+M+Y=K, as shown in Fig. 7. The invention is based on the theory of gray balance, in which a gray balance condition of a region of a heterogeneous network dot of an image partition is set as a target value, or a set of virtual gray balance data is customized as a target value, and then different dot shapes and lines of other regions are selected. The gray balance is adjusted to this virtual gray balance target value, and the image with the same color can be copied. Please take the figures 8 and 9 as an example. The method values are as follows:

1. Set a virtual gray balance target value, where f(Xc)=acX ³ +bcX ² +ccX+dc.....the gray balance curve of the green c is (Xm)=amX ³ +bmX ² +cmX+ Dm.....male red version m gray balance curve f(Xy)=ayX ³ +byX ² +cyX+dy.....the yellow balance y gray balance curve X represents the dot area of 0~100, ac represents The coefficient of the green version, and so on.

2. The gray balance formula of the dot shape and the number of lines intercepting any region is: f'(Xc)=a ^' cX ³ +b ^' cX ² +c ^' cX+d ^' c.....青版 c The gray balance curve f'(Xm)=a ^' mX ³ +b ^' mX ² +c ^' mX+d ^' m...the gray balance curve f' (Xy) of the magenta m = a ^' yX ³ +b ^' yX ² +c ^' yX+d ^' y.....the gray balance curve of the yellow version y

3. With the virtual gray balance as the target value, multiply the gray balance values of other areas by the adjustment value kc, km, ky to adjust to the target value.

f(Xc)=kc*f'(Xc) f(Xm)=km*f'(Xm) f(Xy)=ky*f'(Xy)

4. Substitute the dot correction value of each area into the area of the image partition to adjust the size of the dot signal with the same color after printing.

In the implementation state of the present invention, the embodiments and effects of the present invention will be described as follows:

1. As shown in FIG. 1 , which is a schematic diagram generated when a heterogeneous dot is arranged by image partitioning, which causes a white border or overlap of image boundaries, and when different dot shapes and lines are in the same image. Inconsistencies that result in deep and shallow colors.

2. As shown in FIG. 2, after the present invention adopts different frequencies and dot shapes to be converted into a frequency domain via Fourier, it can be clearly seen that two high-frequency regions of different densities are located at a central position, which is indicated in the present invention. Under the application, the pattern of the printed matter of the securities can be judged by the naked eye or the mobile phone camera, and the authenticity of the printed matter can be judged.

3. Figures 4 and 5 show that when performing image partitioning, vector path clipping is used to obtain the border area of the close, and no white edges and overlaps occur, as shown in Fig. 6.

4. Figure 7 shows how the virtual gray balance is used as the target value to achieve a consistent color. The figure shows that a colored dot is composed of CMY, and with the minimum dot as the base, an equal amount of CMY can be obtained to form a gray balance area, which is replaced by black ink. Therefore, as long as the gray balance is controlled, it is equal to control. The basic conditions of color.

5. In order to avoid the phenomenon that the ink on the dots on the dots is transferred to the paper by the pressure transfer, the invention adopts the innovative technology of image partitioning to arrange the heterogeneous anti-counterfeit dots, and integrates any dot shape and arbitrary dot line numbers to Within the same image. According to the Border Zone Theory, different dot sizes will increase the area around the dots after printing pressure. The larger the number of dots, the smaller the size of the dots, but the larger the expanded area is larger than the number of lines. Outlets. The invention controls the enlargement of the heterogeneous anti-counterfeit dot in the image partitioning arrangement, and adds different paper and printing machine dot enlargement correction values in the partition image, and changes the adjustment mode of the paper and the printing machine which only accept the single channel in the past. In order to accept multi-channel paper and printing machine adjustment methods at the same time, the image color can be solved at one time because of the imbalance caused by different partitions in the partition, and the color inconsistency caused by the inconsistency of the expansion of the heterogeneous anti-counterfeit dots in the image partition arrangement is overcome. The situation happened.

6. The method for virtual gray balance of the present invention mainly refers to the shape and line number of different points in different regions of the image, and specifies a network condition or a gray balance basis in a virtual manner, and then corrects the network points in other different images. The value is close to the virtual curve to achieve color consistency.

In summary, the present invention has been consistent with the requirements of the invention patent, and the patent may be approved, and the application is filed according to law, and an early approval is required. It is to be understood that the scope of the invention is to be construed as being limited by the scope of the invention.

Claims (3)

A method for arranging heterogeneous anti-counterfeit dots and virtual gray balance by image partitioning, mainly to first arrange heterogeneous anti-counterfeit dots, and use the gray balance of one of the mesh conditions as a reference value to make gray balance correction values of other mesh conditions, or different The plate correction value of the dot condition is adjusted by adjusting the virtual gray balance to the target value of each zone's dot signal, and is substituted into the image partitioning area to obtain the final image signal and the dot. For example, the method for arranging heterogeneous anti-counterfeit dots and virtual gray balance by image partitioning as described in the first aspect of the patent application, wherein the method for arranging heterogeneous anti-counterfeit dots in the image partition is: (i) when the color image of the securities print is produced, the partition is high. The frequency and low frequency points are in the same image, so that when the color image sets the heterogeneous network points in different blocks, each area is clearly divided, and the vector path logical cutting method is adopted at the image partition boundary to obtain the closely-connected partition image, and different The distribution state of the frequency dots; (ii) the heterogeneous mesh points of different high frequency and low frequency dot shapes and line numbers respectively arranged in each region of the color image, adopting different frequencies, mesh shapes, and converting into frequency domains via Fourier transform After that, the high-frequency area of two different densities is formed in the center position, and the authenticity can be judged by taking an image with the naked eye or the mobile phone camera. The method for arranging heterogeneous anti-counterfeit dots and virtual gray balance by image partitioning as described in claim 1 of the patent application scope, wherein the method of virtual gray balance is: (i) the shape and number of dots of different regions in the reference image; (ii) The gray balance condition of a certain area of the image partition heterogeneous dot is set as the target value, or a set of virtual gray balance data is set as the target value; (iii) the gray balance of the dot shape and the line number of different areas is adjusted to the virtual Gray Color balance target value, substituting the area adjustment of the image partition, and copying the image with the same color.