Aided design method of long-side banknote feeding magnetic feature authentic identification module

Abstract

The invention discloses an aided design method of a long-side banknote feeding magnetic feature authentic identification module, and the method comprises the steps: feeding banknotes along a long side, scanning the banknotes along a short side direction through a magnetic image sensor, and obtaining a banknote magnetic image; setting the detection width, the channel number and the sensitivity of the magnetic characteristic sensor; a sequence intensity value is selected from a banknote magnetic image sequence, and a magnetic characteristic sensor scanning signal is simulated; morphological expansion of structural elements in the long edge direction is carried out on the paper money magnetic image, and a magnetic characteristic sensor scanning image is simulated; and selecting the long side position of the paper money to carry out multi-mode magnetic characteristic sensor scanning signal simulation. According to the method, a banknote magnetic image and a simulated magnetic characteristic sensor scanning image are displayed, and a position suitable for scanning can be selected from the displayed banknote magnetic image and the simulated magnetic characteristic sensor scanning image; meanwhile, outputting three groups of signal references according to the selected position, and finally confirming whether the signal references are suitable or not to complete aided design.

Description

Technical Field

[0001] The invention relates to the technical field of banknote counterfeiting identification, and in particular to an auxiliary design method of a long-side banknote magnetic feature counterfeiting identification module. Background Art

[0002] With the continuous development of magnetic sensor technology, magnetic image sensors have been successfully developed and have begun to be used in the field of banknote counterfeiting. Through magnetic image sensors, the complex magnetic distribution on banknotes can be detected in conjunction with a uniform paper feed device and converted into a magnetic image, thereby providing the possibility for quantitative counterfeiting of banknote magnetic characteristics. Therefore, quantitative analysis and counterfeiting of the magnetic distribution on banknotes through magnetic images has important research value and has great application potential in the field of counterfeiting. Summary of the invention

[0003] In order to solve the above technical problems, the purpose of the present invention is to provide an auxiliary design method for a long-side banknote magnetic feature counterfeit detection module.

[0004] The purpose of the present invention is achieved through the following technical solutions:

[0005] An auxiliary design method for a long-side banknote magnetic feature counterfeit detection module, comprising:

[0006] A banknote is fed along the long side and scanned along the short side by the magnetic image sensor to obtain a magnetic image of the banknote;

[0007] B. Set the detection width, number of channels and sensitivity of the magnetic feature sensor;

[0008] C. Selecting the intensity values ​​of the series from the banknote magnetic image series to simulate the magnetic feature sensor scanning signal; performing morphological expansion of the structural elements in the long side direction of the banknote magnetic image to simulate the magnetic feature sensor scanning image;

[0009] D. Select the long side position of the banknote to simulate the multi-mode magnetic feature sensor scanning signal.

[0010] Compared with the prior art, one or more embodiments of the present invention may have the following advantages:

[0011] The method will display the magnetic image of the banknote and the simulated scanning image of the magnetic feature sensor, and can select a suitable scanning position on the displayed magnetic image of the banknote and the simulated scanning image of the magnetic feature sensor; at the same time, according to the selected position, 3 groups of signal workers are output for reference, and finally whether it is suitable is confirmed to complete the auxiliary design. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 The invention is a flow chart of an auxiliary design method of a long-side-feeding magnetic feature counterfeit detection module;

[0013] Figure 2 It is a magnetic image of a certain banknote;

[0014] Figure 3 It is to directly take the intensity value on the magnetic image to simulate the magnetic characteristic signal and compare it with the actual magnetic characteristic signal;

[0015] Figure 4 The comparison between the simulated magnetic characteristic signal and the actual magnetic characteristic signal in claim 4;

[0016] Figure 5 The comparison between the simulated magnetic characteristic signal and the actual magnetic characteristic signal in claim 5;

[0017] Figure 6 This is a schematic diagram of the inconsistency between long-side scanning and short-side scanning using a magnetic image sensor. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention will be further described in detail below in conjunction with embodiments and drawings.

[0019] Example: Assume that the magnetic image sensor detects width B image :180mm;Number of channels (number of pixels) C image :720; Sensitivity S image : 60dB.

[0020] Target magnetic feature sensor detection width B sensor : 180mm, number of channels C sensor :18;Sensitivity 60dB.

[0021] Figure 1 The flowchart of the auxiliary design method of the long-side banknote magnetic feature counterfeit detection module is as follows:

[0022] A banknote is fed along the long side, and the magnetic image sensor is used to scan along the short side to obtain the magnetic image of the banknote; see Figure 2 .

[0023] Both magnetic image sensors and magnetic feature sensors are directional. Different banknote inputs correspond to different scanning methods, and the obtained magnetic images and magnetic feature signals are different.

[0024] The magnetic image sensor scans along the short side direction, and the angle error must be controlled within the range of ±10°.

[0025] The detection width B of the magnetic image sensor image , Number of channels (number of pixels) C image , Sensitivity S image .

[0026] B. Set the detection width, number of channels and sensitivity of the magnetic feature sensor;

[0027] Target magnetic feature sensor detection width B sensor 、Number of channels C sensor , generally consistent with products on the market.

[0028] Sensitivity S of magnetic characteristic sensor sensor (Magnification) can be adjusted via factory settings.

[0029] C selects the intensity values ​​of the position surrounding the magnetic image series of the banknote to simulate the scanning signal of the magnetic feature sensor; performs morphological expansion of the structural elements in the long side direction of the banknote magnetic image to simulate the scanning image of the magnetic feature sensor.

[0030] Data is acquired from the magnetic image of the banknote, processed, and the scanning signal of the parameter magnetic feature sensor is simulated.

[0031] Specifically, the magnetic image of the banknote is high with the short side as the height and long side as the length, denoted as I mag (determinant), then the number of columns of the image is equal to the number of pixels C of the magnetic image sensor image ; Total C image Let all pixels in the nth column of the image be denoted by I mag (:,n).

[0032] Then, from the banknote magnetic image series, the strength values ​​of the position surrounding the series are selected to simulate the scanning signal of the magnetic feature sensor:

[0033] Calculate the number of columns N required acq :

[0034]

[0035] Then when the analog magnetic characteristic sensor is at the Nth pos Magnetic characteristic signal X of column position scanning sensor When:

[0036]

[0037] The element E of the morphological dilation is a 1×41 matrix.

[0038] E = [1, 1…1, 1] (3)

[0039] In addition, the point spread function (PSF) of various magnetic feature sensors was obtained through experiments. sensor . Assume that the point spread function is a matrix with equal and odd number of rows and columns. For the point spread function PSF of the magnetic feature sensor not recorded in the database sensor , the normal distribution function is used for simulation.

[0040] The simulated magnetic feature sensor scanning image I sensor_sim :

[0041]

[0042] Where: is the image morphological dilation operation; * is the image convolution operation;

[0043] Indicates that the image Inverse image convolution.

[0044] D. Select the position on the long side to realize the multi-mode magnetic feature sensor scanning signal simulation, and let the experts select the appropriate signal to complete the auxiliary design.

[0045] The magnetic image of the banknote will be displayed. mag , simulated magnetic feature sensor scanning image I sensor_sim .

[0046] At the same time, according to the selected position N pos Column, output 3 groups of signals, respectively:

[0047] (1) Magnetic image of banknote N pos Magnetic characteristic signal I mag (:,N pos ); For comparison between simulated signal and actual signal, see Figure 3 .

[0048] (2) Simulate the magnetic characteristic sensor at the Nth pos Magnetic characteristic signal X of column position scanning sensor ; Comparison between simulated signal and actual signal Figure 4 .

[0049] (3) Scanning image I of the simulated magnetic feature sensor sensor_sim Nth pos Magnetic characteristic signal I sensor_sim (:,N pos ). For comparison between simulated signal and actual signal, see Figure 5 .

[0050] Then the magnetic image of the banknote I can be displayed mag , simulated magnetic feature sensor scanning image I sensor_sim On the top, select a position on the long side that is suitable for scanning; and based on 3 groups of signals (including 2 groups of simulation values), finally confirm whether it is suitable and complete the auxiliary design. Figure 6 This is a schematic diagram of the inconsistency between long-side scanning and short-side scanning using a magnetic image sensor.

[0051] Although the embodiments disclosed in the present invention are as above, the above contents are only embodiments adopted for facilitating the understanding of the present invention and are not intended to limit the present invention. Any technician in the technical field to which the present invention belongs can make any modifications and changes in the form and details of the implementation without departing from the spirit and scope disclosed in the present invention, but the patent protection scope of the present invention shall still be subject to the scope defined in the attached claims.

Claims

1. An auxiliary design method for a long-side banknote magnetic feature counterfeit detection module, characterized in that: include: A banknote is fed along the long side and scanned along the short side by the magnetic image sensor to obtain a magnetic image of the banknote; B. Set the detection width, number of channels and sensitivity of the magnetic feature sensor; C. Selecting the intensity values ​​of the series from the banknote magnetic image series to simulate the magnetic feature sensor scanning signal; performing morphological expansion of the structural elements in the long side direction of the banknote magnetic image to simulate the magnetic feature sensor scanning image; D. Select the long side position of the banknote to simulate the multi-mode magnetic feature sensor scanning signal.

2. The auxiliary design method of the long-side banknote magnetic feature counterfeit detection module according to claim 1, characterized in that: The magnetic image sensor and the magnetic characteristic sensor are both directional, and different banknotes are fed in corresponding to different scanning modes, so the obtained magnetic images and magnetic characteristic signals are different.

3. The auxiliary design method of the long-side banknote magnetic feature counterfeit detection module according to claim 1, characterized in that: In the A: The magnetic image sensor scans along the short side direction, and the angle error is controlled within the range of ±10°; The detection width of the magnetic image sensor is B image , the number of channels is C image , sensitivity is S image .

4. The auxiliary design method of the long-side banknote magnetic feature counterfeit detection module according to claim 1, characterized in that: In said B: The detection width of the target magnetic feature sensor is B sensor , the number of channels is C sensor , the sensitivity of the magnetic characteristic sensor is S sensor .

5. The auxiliary design method of the long-side banknote magnetic feature counterfeit detection module according to claim 3 or 4, characterized in that: In the above-mentioned C, data is obtained from the magnetic image of the banknote, processed, and the scanning signal of the parameter magnetic feature sensor is simulated, including: The magnetic image of the banknote is high by the short side and long by the long side, denoted by I mag , then the number of columns of the image is equal to the number of pixels C of the magnetic image sensor image ; Total C image Column; let all pixels in the nth column of the image be denoted by I mag (:,n); Then, from the banknote magnetic image series, the strength values ​​of the position surrounding the series are selected to simulate the scanning signal of the magnetic feature sensor: Calculate the number of columns N required acq : Then when the analog magnetic characteristic sensor is at the Nth pos Magnetic characteristic signal X of column position scanning sensor When:

6. The auxiliary design method of the long-side banknote magnetic feature counterfeit detection module according to claim 5, characterized in that: In the above C, the morphological expansion of the structural elements in the long side direction of the banknote magnetic image is performed to simulate the scanning image of the magnetic feature sensor, including: The element E of morphological expansion is 1×(2N acq +1) matrix, N acq The number of rows to be obtained is calculated by formula (1): E＝[1，1…1，1] (3) In addition, the point spread function (PSF) of various magnetic feature sensors was obtained through experiments. sensor , assuming that the point spread function is a matrix with equal and odd number of rows and columns; for the point spread function PSF of the magnetic feature sensor not recorded in the database sensor , the normal distribution function is used for simulation; The simulated magnetic feature sensor scanning image I sensor_sim : Where: is the image morphological dilation operation; * is the image convolution operation; Indicates that the image Inverse image convolution.

7. The auxiliary design method of the long-side banknote magnetic feature counterfeit detection module according to claim 6, characterized in that: The D includes: displaying the magnetic image I of the banknote mag , simulated magnetic feature sensor scanning image I sensor_sim ; At the same time, according to the selected position N pos Column, output 3 groups of signals, respectively: (1) Magnetic image of banknote N pos Magnetic characteristic signal I mag (:,N pos ); (2) Simulate the magnetic characteristic sensor at the Nth pos Magnetic characteristic signal X of column position scanning sensor ; (3) Scanning image I of the simulated magnetic feature sensor sensor_sim Nth pos Magnetic characteristic signal I sensor_sim (:,N pos ); The expert can then display the magnetic image of the banknote I mag , simulated magnetic feature sensor scanning image I sensor_sim On the top, select a position on the long side that is suitable for scanning; and based on the three groups of signals, including two groups of simulation values, finally confirm whether it is suitable and complete the auxiliary design.

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