JP7161925B2 - Image processing method and system for line drawing pattern - Google Patents

Description

The present invention provides an image processing method for distinguishing (extracting) a drawing line having at least a first line width from a line drawing pattern including two or more drawing lines having different line widths printed on a base material, and an image processing method therefor. Regarding the system.

In particular, from the image data of the line drawing pattern, the primary intensity of each object along the scanning line that crosses each object is obtained as a waveform component, and from the waveform component, the value of the waveform width of each object and the value of the primary intensity are obtained. By multiplying the area value of the area surrounded by the peak value and the waveform component, a drawing line having at least a first line width is discriminated (extracted) from a line drawing pattern including two or more drawing lines with different line widths. An image processing method and system for generating and discriminating (extracting) a score of each drawing suitable for image processing.

Conventionally, in order to prevent counterfeiting and alteration of securities such as stock certificates and cards such as credit cards, background patterns, colorful patterns, relief patterns, etc. consisting of a collection of complicated lines have been applied to the surface of securities and cards. Or, a latent image is applied to the ground pattern, colored pattern, relief pattern, etc., and these patterns are made to appear by a copying machine, etc., or image data is read by a dedicated reading device. A method of acquiring, analyzing, and discriminating is known.

For example, in Japanese Patent Application Laid-Open No. 2012-121247 (Patent Document 1), lines consisting of image lines and non-image lines arranged alternately with a line width of a specific ratio, which are visually recognized with the naked eye at a constant density A printed matter authentication method using image processing for extracting a predetermined frequency component by frequency-analyzing the is disclosed. In Japanese Patent Application Laid-Open No. 2012-187738 (Patent Document 2), frequency analysis is performed on intervals in a specific area of a plurality of image line units arranged concentrically, and based on information embedded in the area, A method for authenticating a printed matter using image processing for extracting frequency components is disclosed. Further, in Japanese Patent Application Laid-Open No. 8-212418 (Patent Document 3), the image information of the image line of the portion where the latent image is applied is removed by binarization, and the position of the image line of the portion where the latent image is not applied is disclosed. A reading inspection method using image processing is disclosed for discriminating authenticity by recognizing, comparing, and collating remaining binary image shapes.

On the other hand, due to the rapid development of digital devices in recent years, image data such as background patterns, colored patterns, and relief patterns can be acquired using mobile devices such as smartphones equipped with general-purpose small cameras, and general-purpose small digital cameras. If a line having a certain line width can be discriminated from the image data, it can be easily used for authenticity determination, which is convenient.

However, in the authentication methods described in Patent Documents 1 to 3 above, a dedicated high-precision digital camera is used to acquire image data from background patterns, colored patterns, relief patterns, and the like. In order to capture image data with stable chroma, a dedicated lighting fixture is often used together. As described above, the current situation is that the authentication methods described in Patent Documents 1 to 3 do not use a general-purpose small camera built in a mobile device such as a smart phone as described above.

This is because when using a small general-purpose camera built into a mobile device such as a smartphone or a small general-purpose digital camera, the exposure is not stable and the resolution is low compared to a dedicated camera for acquiring image data. Furthermore, since the shooting environment such as illumination is not constant, defects such as blurring and chipping occur in the acquired image data, making it impossible to acquire accurate and stable image data.

JP 2012-121247 A JP 2012-187738 A JP-A-8-212418

Therefore, according to the present invention, even if a general-purpose small camera or a general-purpose small digital camera built in a mobile device such as a smartphone is used, a specific line width can be obtained from a line drawing pattern such as a background pattern, a colored pattern, or a relief pattern. An object of the present invention is to provide an image processing method and system capable of accurately and stably extracting and discriminating a streak.

The inventors of the present invention have found an image effective for accurately and stably extracting a drawing line having a specific line width from image data of a line drawing pattern obtained using a general-purpose small camera built in a smartphone or the like. As a result of intensive studies on data correction methods, etc., the line width of each image line is obtained from the image data as the intensity of the waveform component, and the intensity of the waveform component is scored using elements representing the characteristics of the waveform component. For example, the inventors have found that an object line having a specific line width can be accurately and stably discriminated (extracted) from a group of object lines, and have completed the present invention.

That is, according to the present invention, an image processing method for determining a drawing line having at least a first line width from a line drawing pattern including two or more drawing lines having different line widths printed on a base material. a step of acquiring image data of a line drawing pattern including two or more lines of different line widths printed on a base material by an imaging unit; a step of acquiring, as a waveform component, the primary intensity of each object line along a scanning line crossing each object line, and obtaining a certain primary intensity threshold value from the waveform component of the primary intensity by a waveform width analysis unit obtaining the waveform width of the waveform component corresponding to each drawing line in the step of obtaining the waveform width of the waveform component corresponding to each drawing line, and the first order of the waveform component corresponding to each drawing line above the threshold value from the waveform component of the first order intensity by the first order intensity analysis unit obtaining the peak value of the intensity; obtaining, from the waveform component of the primary intensity, the area of the region above the threshold value and surrounded by the waveform component corresponding to each drawing line by the area analysis unit; The generation unit multiplies the waveform width value, the primary intensity peak value, and the area value of the waveform component of each image line to obtain a score representing the line width of each image line along the scan line. An image processing method is provided, comprising the steps of: generating, and determining, from the score of each image, an image line having at least a first line width by a determination unit.

Further, the present invention can be configured as an image processing system by incorporating the image processing method described above into hardware.

Specifically, according to the present invention, an image for distinguishing a drawing line having at least a first line width from a line drawing pattern including two or more drawing lines having different line widths printed on a base material. A processing system, comprising: an imaging unit that acquires image data of a line drawing pattern including two or more lines with different line widths printed on a base material; and a wired or wireless transmission of the image data to an image processing device. a receiving unit for receiving the image data transmitted from the image acquiring device; and from the image data of the line drawing pattern along a certain scanning line that crosses each drawing line. a drawing intensity reading unit for acquiring the primary intensity of each drawing as a waveform component; and obtaining the waveform width of the waveform component corresponding to each drawing at a certain primary intensity threshold from the waveform component of the primary intensity. a waveform width analysis unit, a primary intensity analysis unit for obtaining, from the waveform component of the primary intensity, a peak value of the primary intensity of the waveform component that is above the threshold value and corresponds to each drawing line; an area analysis unit for obtaining, from the waveform component, the area of a region above the threshold value and surrounded by the waveform component corresponding to each drawing line, the waveform width value of the waveform component of each drawing line, and the primary intensity a score generator that multiplies the peak value and the area value to generate a score representing the line width of each image for each image along the scan line; and from the score for each image, at least a first There is provided an image processing system comprising an image processing apparatus including a discriminating unit that discriminates an image line having a line width of 1.

In the image processing method and image processing system of the present invention, image data is obtained from a line drawing pattern including two or more lines with different line widths printed on a base material, such as a background pattern, a colored pattern, and a relief pattern. to get In this case, the image capturing unit basically does not depend on the resolution of the image, and can use a compact camera built into a mobile device such as a smartphone or a general-purpose digital camera. There is no need for special lighting fixtures or enclosures to keep the lines constant, and variations in the distance, tilt, and brightness between the line drawing pattern and the camera are acceptable. Further, when the line drawing pattern is in color, in order to reduce the load of image processing, the image data may be converted to gray scale of 256 gradations after acquiring the image data.

The drawing lines included in the line drawing pattern are obtained from the image data by the drawing line intensity reading unit as waveform components of the primary intensity of each drawing line along a scanning line crossing each drawing line. Then, from the waveform component of the primary intensity of each object, the waveform width of the waveform component corresponding to each object at a certain threshold value of the primary intensity is obtained as an index representing the characteristics of each object (the waveform component of the primary intensity). , the area of the region surrounded by the peak value of the primary intensity of the waveform component corresponding to each drawing line above the threshold and the waveform component corresponding to each drawing line above the threshold is the waveform width analysis. section, primary strength analysis section, and area analysis section.

In the present invention, in order to more clearly and emphasize the features of each drawing line (the waveform component of the primary intensity), the score generator generates the waveform width value of the waveform component of each drawing line, the peak value of the primary intensity, and the It is processed by multiplying by the area value to produce a score representing the line width of each streak along the scan line.

Then, the score of each image line emphasized by the score generation unit can be obtained by using a general-purpose small camera built in a mobile device such as a smartphone with unstable exposure and low resolution, or by lighting. Even when photographing is performed under an inconsistent photographing environment, it is possible to accurately reproduce and emphasize the characteristics such as the line width of each actual drawing line based on the obtained image data of the line drawing pattern.

For this reason, in the image processing method and image processing system of the present invention, when the score generation unit generates a score representing the line width of each object line, the difference in the actual line width of each object line is small. Even so, by comparing the score of each drawing line in the discriminating unit, it is possible to accurately and stably discriminate the difference in line width (for example, thick or thin) of each drawing line in the line drawing pattern.

For example, according to the image processing method and image processing system of the present invention, by comparing the score of each image, the image having the largest line width among the images in the line drawing pattern, the image having the second It is possible to accurately and stably discriminate and extract an image line having a thick line width, an image line having the thinnest line width, and the like.

Further, according to the present invention, if it is possible to accurately and stably determine and extract a drawing line having at least the first line width from among the drawing lines in the line drawing pattern, the first line width is It is also possible to accurately and stably discriminate and extract objects having different second line widths. and the 3rd thickest line width, 1st to 3rd thinnest line widths, 1st, 3rd and 4th thinnest line widths, etc. can be discriminated and extracted.

In the present invention, a specific code such as a two-dimensional code such as a QR code (registered trademark) or a geometric/non-geometric figure may be printed on the substrate together with the line drawing pattern. The image data can include image data relating to specific codes and graphics acquired by the photographing section, and the arrangement of scanning lines with respect to the line drawing pattern is determined by the scanning line designating section based on the image data of the specific codes and graphics. can be done.

For example, if a line drawing pattern is arranged in a predetermined positional relationship with respect to a specific code printed on a base material, the scanning line designating unit can set the specific code or figure in the image data as a reference point. Based on this, it is possible to calculate and determine the arrangement of scanning lines with respect to the line drawing pattern in the image data. Alternatively, the scanning line designating section may read and determine the predetermined scanning line layout for the line drawing pattern in the image data from a predetermined scanning line layout pattern table based on the specific code or graphic in the image data. .

Also, the scan lines are preferably determined or arranged to cross each image line at the same angle. If the scanning line intersects each image line at a different angle, even if the image line has the same line width, the waveform width analysis unit, primary intensity analysis unit, and area analysis unit may cause different waveform widths, different peak values, This is because detection of primary intensity waveform components having different area areas leads to erroneous determination that the lines have different line widths. In the specification of the present application, the "angle" at which a scanning line crosses an image line means the intersection angle between the image line and the scanning line when the image line is a straight line, and when the image line is a curved line. means the intersection angle between the tangent to the image line and the scanning line at the portion crossed by the scanning line.

In the image processing method and image processing system of the present invention, the threshold of each image line can be corrected according to the brightness of each corresponding image line based on the image data. For example, based on the image data, the threshold of each object can be corrected so that the corresponding objects have the same brightness. Instead of correcting the threshold value of each image line, the waveform component of the primary intensity of each image line may be corrected based on the image data so that the corresponding image lines have the same brightness.

If there is a variation in brightness even within the same line drawing pattern, the drawing line intensity reading unit will change the primary intensity (for example, density) of the waveform component of each drawing line obtained from the image data of the line drawing pattern. Variation may occur. Therefore, by correcting the waveform component of the primary intensity or its threshold so that the brightness of each image line is the same so that the characteristics such as the line width of each image line can be accurately reproduced, the image line can be obtained. It is possible to improve the accuracy of the waveform component of the primary intensity of each drawing obtained by the intensity reading unit and the score of each drawing emphasized by the score generating unit.

According to the image processing method and system of the present invention, from image data of a line drawing pattern, the primary intensity of each drawing line along a scanning line that crosses each drawing line is obtained as a waveform component, and each waveform component is obtained from the waveform component. At least a first It is possible to obtain a score for each streak suitable for discriminating (extracting) streaks having a line width of .

In addition, the score of each emphasized image line is not stable even if the exposure and exposure are not stable, and even if you use a general-purpose small camera built in a mobile device such as a smartphone with low resolution, or if the lighting etc. is constant. Even when the image is captured in an unfavorable environment, it is possible to accurately reproduce and emphasize the line width and other characteristics of each line drawing based on the obtained image data of the line drawing pattern.

1 is a schematic diagram showing the system configuration of an image processing system of the present invention; FIG. 4 is a flow chart showing the procedure of the image processing method of the present invention; 1 is a schematic diagram showing a line drawing pattern (color pattern) and a QR code (registered trademark) printed on a substrate used in the present invention; FIG. FIG. 4 is a schematic diagram illustrating a method of arranging scanning lines from the line drawing pattern and QR code (registered trademark) image data shown in FIG. 3 ; 5 is an enlarged view partially enlarging the schematic diagram of the method of arranging scanning lines shown in FIG. 4; FIG. FIG. 6 is a schematic diagram showing waveform components of primary intensity obtained by scanning lines crossing each drawing line from the image data of the line drawing pattern shown in FIG. 5 ; FIG. 7 is a schematic diagram showing a primary intensity waveform component obtained from the image data of the line drawing pattern shown in FIG. 6 and a method of obtaining a waveform width of the waveform component corresponding to each drawing line at a certain primary intensity threshold; . FIG. 7 is a schematic diagram showing the waveform component of the primary intensity shown in FIG. 6 and a method of obtaining the peak value of the primary intensity of the waveform component above the threshold value and corresponding to each drawing line; FIG. 7 is a schematic diagram showing how to obtain the area of the area surrounded by the waveform component of the primary intensity shown in FIG. 6 and the waveform component above the threshold and corresponding to each drawing line; Illustrates how to generate a score representing the line width of each streak by multiplying the waveform width value, the primary intensity peak value and the area value to discriminate streaks with a first line width. 1 is a schematic diagram.

An image processing method and an image processing system according to an embodiment of the present invention will be described in detail below with reference to the drawings. The present invention is not limited to the embodiments shown below, and various modifications are possible without departing from the technical idea of the present invention.

The schematic diagram of FIG. 1 shows the system configuration of an image processing system 1 of this embodiment.

As can be understood with reference to FIG. 1, the present embodiment extracts at least a first line width from a line drawing pattern 40 including two or more drawing lines 42 of different line widths printed on a substrate 4. The image processing system 1 for discriminating a drawing 42 having a base material 4 is roughly divided into an image acquisition device 2 for obtaining information about the drawing 42 from a base material 4, a line drawing pattern 40, etc., as image data 5, and an image data 5. is processed into information related to the image line 42 suitable for distinguishing (extracting) the image line.

The image acquisition device 2 includes an imaging unit 20 for acquiring image data 5 of a line drawing pattern 40 including two or more drawing lines 42 having different line widths printed on a base material 4 and a two-dimensional code 41; to the image processing apparatus 3 by wire or wirelessly.

The imaging unit 20 basically does not depend on the resolution of the image, and can use a compact camera or a general-purpose digital camera built into a mobile device such as a smartphone. There is no need for special lighting fixtures or enclosures to achieve this, and variations in the distance, tilt, and brightness between the line drawing pattern 40 and the camera do not matter. Further, when the line drawing pattern 40 is in color, in order to reduce the load of image processing, the image data 5 may be converted into gray scale of 256 gradations after obtaining the image data 5 .

The image processing device 3 includes a receiving unit 30 for receiving the image data 5 transmitted from the image acquisition device 2 in order to acquire the waveform component 7 of the primary intensity of each drawing line 42 of the line drawing pattern 40 from the image data 5; A scanning line specifying unit 32 that determines the arrangement of scanning lines 52 with respect to the line drawing pattern 40 based on the image data 51 of the two-dimensional code 41; and an image line intensity reading unit 31 for acquiring the primary intensity of each image line 42 along the line as a waveform component 7 . In the image processing system 1 of the present embodiment, transmission and reception of the image data 5 between the image acquisition device 2 and the image processing device 3 are not limited to wired or wireless, and may be performed using an Internet line or the like.

If the scanning line 52 crosses each image line 42 at a different angle, even if the image line 42 has the same line width, the waveform width analysis unit 33, the primary intensity analysis unit 34, and the area analysis unit 35, which will be described later. Since there is a risk that the objects 42 having different line widths may be detected depending on the conditions, the objects 42 are determined or arranged so as to traverse the objects 42 at the same angle (see FIG. 4).

Further, the image processing apparatus 3 extracts a certain 1 A waveform width analysis unit 33 that obtains a waveform width 70 of a waveform component corresponding to each object 42 at the threshold value 73 of the next intensity, and a waveform width analysis unit 33 that obtains the waveform component 7 of the first intensity that corresponds to each object 42 above the threshold value 73 . A primary intensity analysis unit 34 for obtaining a peak value 71 of the primary intensity of the waveform component, and an area above the threshold value 73 and surrounded by the waveform component corresponding to each drawing line 42 from the waveform component 7 of the primary intensity. and an area analysis unit 35 for obtaining the area 72 .

In this case, the image processing system 1 of the present embodiment can correct the threshold value 73 of each object line 42 according to the brightness of each corresponding object line 42 based on the image data 50 . For example, based on the image data 50, the threshold value 73 of each object line 42 can be corrected so that each corresponding object line 42 has the same brightness. Instead of correcting the threshold value 73 of each object 42, the waveform component 7 of the primary intensity of each object 42 is corrected based on the image data 50 so that the corresponding objects 42 have the same brightness. can be corrected.

The image processing device 3 reproduces and emphasizes the characteristics such as the line width of each image line 42 from the acquired image data 50 of the line drawing pattern 40, and reproduces and emphasizes each image line so that the difference between them can be determined. a score generator 36 that generates a score 8 for each streak 42 along the scan line 52 by multiplying the waveform width value 70, the primary intensity peak value 71 and the area value 72 of the waveform components of 42; A discrimination unit 37 is provided for discriminating a drawing line 42 having at least the first line width from the score 8 of each drawing line 42 .

As described above, in the image processing system 1 of the present embodiment, the score generation unit 36 obtains the score 8 representing the line width of each object line 42, so that the difference in the actual line width of each object line 42 is small. Even in such a case, the discrimination unit 37 can compare the score 8 of each drawing line 42, and the difference in line width (for example, thick or thin) of each drawing line 42 in the line drawing pattern 40 can be determined. Accurate and stable determination is possible.

For example, by comparing the score 8 of each object line 42, the object line 42 having the largest line width and the object line 42 having the second thickest line width among the respective object lines 42 in the line drawing pattern 40 are determined. . . , the image line 42 having the thinnest line width can be accurately and stably discriminated and extracted.

Further, if it is possible to accurately and stably discriminate and extract the drawing line 42 having at least the first line width from among the drawing lines 42 in the line drawing pattern 40, the second line width different from the first line width can be extracted. can be accurately and stably identified and extracted. and the third thickest line width, the third to third thinnest line widths, the first, third, and fourth thinnest line widths, etc. Moreover, it can be stably discriminated and extracted.

The flowchart of FIG. 2 shows the procedure of the image processing method of this embodiment. Each step in the image processing method of this embodiment will be described with reference to FIG.

This embodiment is an image processing method for determining a drawing line 42 having at least a first line width from a line drawing pattern 40 including two or more drawing lines 42 having different line widths printed on a base material 4. and
a step of acquiring image data 5 of a line drawing pattern 40 including two or more drawing lines 42 having different line widths printed on a base material 4 and a two-dimensional code 41 by an imaging unit 20 (S1);
a step (S2) of determining the arrangement of the scanning lines 52 with respect to the image data 50 of the line drawing pattern 40 based on the image data 51 of the two-dimensional code 41 by the scanning line designating unit 32;
a step (S3) of obtaining, as a waveform component 7, the primary intensity of each image line 42 along a scanning line 52 crossing each image line 42 from the image data 50 of the line drawing pattern 40 by the image line intensity reading unit 31; ,
A step (S4) in which the waveform width analysis unit 33 obtains the waveform width 70 of the waveform component corresponding to each image line 42 at a certain primary intensity threshold value 73 from the waveform component 7 of the primary intensity;
A step (S5) of obtaining, from the waveform component 7 of the primary intensity, the peak value 71 of the primary intensity of the waveform component corresponding to each image line 42 and above the threshold value 73 by the primary intensity analysis unit 34;
A step (S6) in which the area analysis unit 35 obtains the area 72 of the area surrounded by the waveform component corresponding to each image line 42 above the threshold value 73 from the waveform component 7 of the primary intensity;
The score generator 36 multiplies the waveform width value 70, the primary intensity peak value 71, and the area value 72 of the waveform component of each image line 42 to obtain the line width of each image line 42 along the scanning line 52. and a step (S8) of determining, from the score 8 of each image line 42, the image line 42 having at least the first line width by the determination unit 37 .

As described above, in the image processing method of the present embodiment, the score 8 representing the line width of each object line 42 is obtained by the score generator 36, so that the difference in the actual line width of each object line 42 is small. Even in such a case, the discrimination unit 37 can compare the score 8 of each drawing line 42, and the difference in line width (for example, thick or thin) of each drawing line 42 in the line drawing pattern 40 can be accurately determined. And it can be determined stably.

Next, the image processing method in each step of this embodiment will be described in detail below with reference to the drawings.

The schematic diagram of FIG. 3 shows a line drawing pattern (color pattern) 40 and a QR code 41 (registered trademark) printed on the base material 4 used in this embodiment.

As shown in FIG. 3, the colored pattern 40 used in this embodiment is arranged at a predetermined position with respect to the QR code 41 (registered trademark). The colorful pattern 40 means a fine pattern that combines geometric patterns such as wavy lines, arcs, and circles composed of streaks or figures. It may include a combination of geometric patterns regardless of the shape, such as a shape or a linear shape.

In the colorful pattern 40, one part of the colorful pattern waveform corresponds to one character of the code, as shown in FIG. 3, for example. In this embodiment, the number of lines and the line arrangement pattern composed of 0.3-point thin lines and 0.6-point thick lines are assigned to correspond to numbers from the colored pattern waveforms.

The schematic diagram of FIG. 4 exemplifies a method of arranging the scanning lines 52 from the image data 5 of the line drawing pattern 40 and the QR code 41 (registered trademark) (thick arrow portion). The enlarged view of FIG. 5 shows a partially enlarged view of the fifth digit in the method of arranging the scanning lines 52 shown in FIG. In the schematic diagram of FIG. 6, a waveform component 7 of the primary intensity obtained from the image data 5 of the line drawing pattern 40 by scanning lines 52 (thick arrow portions shown in FIG. 5) crossing each drawing line 42. is schematically shown. 5 illustrates the case where the scanning line 52 crosses each of the seven image lines 42, seven waveform components 7 are also obtained in FIG. When crossing the streak 42 (FIG. 4), six waveform components 7 are acquired, although not shown. 6, the vertical axis represents the intensity (brightness) of the waveform component 7, and the horizontal axis represents the position (number of dots) of each waveform component 7. In FIG.

As shown in FIGS. 4 to 6, the primary intensity waveform component 7 obtained from the image data 50 of the colored pattern 40 is obtained as follows.
Step 1: Convert the color image data 5 of the colored pattern 40 and the QR code 41 (registered trademark) acquired by the photographing unit 20 into grayscale image data (256-gradation grayscale).
Step 2: The position of the QR code 41 (registered trademark) is detected by the scanning line designating unit 32, and the position of the scanning line 52 with respect to the image data 50 of the line drawing pattern 40 is calculated from the position of the QR code 41 (registered trademark).
Step 3: For one digit, waveform components are obtained from the grayscale data of the primary intensity of each image line (7 or 6 image lines 42 in this embodiment, see FIG. 4) on the scanning line 52. get.

Also, the position of the scanning line 52 with respect to the image data 50 of the line drawing pattern 40 from the position of the QR code 41 (registered trademark) is obtained as follows.
Step 1A; Movement of coordinates can be realized by multiplication of matrices.
Step 2A: XY coordinate movement of the horizontal axis X and the vertical axis Y can be realized with a 3×3 matrix using a perspective transformation matrix. A perspective transformation matrix can be calculated by giving 4 points before transformation and 4 points after transformation. and Step 3A; using the 4 points (or 3 points) of the QR Code 41 (registered trademark) position of the master image and the 4 points (or 3 points) of the QR Code 41 (registered trademark) position of the decoded image, transform Compute a matrix. By multiplying the coordinate point A of the master image by the transformation matrix, the corresponding coordinate point on the decoded image can be calculated.
Step 4A: This mechanism makes it possible to obtain which coordinates (X', Y') in the decoded image correspond to the analysis scanning line coordinates (X, Y) set in the master image.

In the schematic diagram of FIG. 7, the waveform component 7 of the primary intensity obtained from the image data 50 of the colorful pattern 40 and the waveform width 70 of the waveform component corresponding to each image line 42 at a certain threshold value 73 of the primary intensity. FIG. 8 is a schematic diagram showing the determination of the primary intensity waveform component 7 and the primary intensity peak value 71 of the waveform component above the threshold value 73 and corresponding to each drawing line 42. 9 shows the area 72 of the area surrounded by the waveform component 7 of the primary intensity and the waveform component corresponding to each streak 42 above the threshold value 73. direction is indicated. 5 illustrates the case where the scanning line 52 crosses seven image lines 42, seven waveform components 7 are also obtained in FIGS. 4 (FIG. 4), six waveform components 7 are obtained (not shown). 7 to 9, the vertical axis represents the intensity (brightness) of the waveform component 7, and the horizontal axis represents the position (number of dots) of each waveform component 7. FIG.

From the obtained image data 50 of the colorful pattern 40, the waveform width analysis unit 33 extracts a certain 1 The waveform width 70 of the waveform component corresponding to each object 42 at the threshold value 73 of the next intensity is obtained, and the first intensity analysis unit 34 determines the width of each object 42 above the threshold value 73 from the waveform component 7 of the first intensity. Then, the area analysis unit 35 determines the peak value 71 of the primary intensity waveform component 7 that is above the threshold value 73 and is surrounded by the waveform component corresponding to each image line 42. The area 72 of the truncated region is determined.

In the image processing system 1 of this embodiment, in order to improve the accuracy of the waveform width 70, the peak value 71, and the area 72 obtained from the waveform component 7 of the primary intensity, the threshold value 73 of each image line 42 is calculated based on the image data 5. can be corrected according to the brightness of each corresponding image line 42 . Further, instead of correcting the threshold value 73 of each object 42, the waveform component 7 of the primary intensity of each object 42 is corrected based on the image data 5 so that the corresponding objects 42 have the same brightness. can be corrected.

Next, a method for analyzing the above-described primary intensity waveform component 7 (hereinafter also referred to as a “waveform graph”) will be described more specifically. In the image processing method and image processing system 1 of the present embodiment, the analysis of the intensity of the waveform component 7 of the primary intensity (hereinafter also referred to as "brightness") is performed, for example, by the following procedure.

First, based on the measurement of the waveform component 7 of the image data 50 representing the intensity (brightness) of the colored pattern 40, the waveform width analysis unit 33 calculates the waveform width _fn of each waveform component 7 from the number of dots. (See FIG. 7). The waveform width _fn of each waveform component 7 is measured from right to left facing the waveform graph of FIG.

In the waveform graph of FIG. 7, the vertical axis represents the intensity (brightness) of the waveform component 7, the horizontal axis represents the position (number of dots) of each waveform component 7, and the upper side of the vertical axis represents the number of dots. It represents a state of high intensity (state of low brightness, dark state, dark state). As a measurement object, when measuring the line drawing pattern (color pattern) 40 in the width direction, the intensity changes from a weak state to a strong state (from a high lightness state to a low lightness state, from a whitish state to a blackish state). ) and waveform components 7 are observed, each waveform component 7 represents the characteristics of each image line 42 of the color pattern.

Specifically, if the maximum value among all the waveform components 7 in the waveform _graph of FIG. is the lowest value of _b1 . Then, if the position obtained by distributing the difference between the lowest value _bn of each waveform component 7 and the maximum value a among all the waveform components 7 at a ratio of 7:3 is set as the threshold value _cn of each waveform component 7, for example, in the first waveform _The threshold becomes c1.

In the _first waveform, it rises from the lowest value b1, which is the starting point of the waveform component ₇ , and the crossing _point with the threshold value c1 is set to d1. Assuming that the point at which the threshold value c1 intersects is e1, the distance (the _number of dots) between the intersection _point d1 and the intersection _point e1 is the waveform width f1 of the waveform component ₇ in the _first waveform.

Then, the waveform component 7 in the first waveform descends as it is, and the point at which the lowest value is reached is the starting point (lowest value) b2 of the waveform component 7 in the _second waveform. Similarly, the threshold value c2 of the _second waveform is calculated from the difference between the lowest value b2 and the maximum value a in all the waveform components 7, and the rise and fall of the waveform component 7 in the _second waveform are traced. Thus, the intersection points d2 and e2 with the threshold value c2 _are measured, and the waveform width f2 of the waveform component ₇ in the _second waveform is calculated from the distance ₍ dot number). By repeating the above measurement for the number of waveforms, the waveform width f ₁ to f ₇ (FIG. 7) from the first waveform to the seventh waveform or the waveform width f from the first waveform to the sixth waveform ₁ to f ₆ (not shown) are calculated.

As a result, in the waveform graph of FIG. 7, the waveform width fn of each waveform component 7 is "7" for the waveform width _f1 of the _first waveform on the right end, and "7" for the waveform width f1 of the second waveform from the right. _The waveform width f2 of the waveform component is "7", the waveform width f3 of the _third waveform component is "6", and the waveform width f4 of the _fourth waveform component is "6". , the waveform width f5 of the waveform component of the _fifth waveform is "7", the waveform width f6 of the waveform component of the sixth _sixth waveform is "10", and the seventh waveform The waveform width _fn of the waveform component of is "7".

Next, based on the measurement of the waveform component 7 of the image data 50 of the colorful pattern 40 expressing the intensity (brightness and darkness), the primary intensity analysis unit 34 calculates the peak value _jn of each waveform component 7 (Fig. 8 reference). In the waveform graph of FIG. 8, the vertical axis represents the intensity (brightness) of the waveform component 7, and the horizontal axis represents the position (number of dots) of each waveform component 7, as in FIGS. be.

Specifically, let _gn be the inflection point at which the waveform component 7 in each waveform exceeds the threshold cn and turn from rising to descent, and _let h be the minimum value in all the waveform components 7. Then, the inflection point _gn and the entire waveform The difference from the minimum value h in the component 7 becomes the peak value _jn of the waveform component 7 in each waveform.

For example, in the first waveform, if the inflection point at which the waveform component 7 rises beyond the intersection _point d1 with the threshold value c1 and reaches _a peak and turns downward is g1, then the inflection _point g1 and the _entire waveform The difference from the minimum value h in the component 7 becomes the peak value j1 of the waveform component 7 in the _first waveform.

In the _second waveform, if the inflection point at which the waveform component ₇ rises beyond the intersection point d2 with the threshold value c2 and reaches a peak and turns downward is _g2 , then the inflection point _g2 and all the waveform components The difference from the minimum value h in 7 is the peak value j2 of the waveform component 7 in the _second waveform. By repeating the above measurement for the number of waveforms, the peak values j ₁ to j ₇ (FIG. 8) from the first waveform to the seventh waveform or the peak value j from the first waveform to the sixth waveform ₁ to j ₆ (not shown) are calculated.

As a result, in the waveform graph of FIG. 8, the peak value _jn of _each waveform component 7 is "0.56×255" for the peak value j1 of the waveform component of the first waveform on the right end, and The peak value j2 of the waveform component of the _second waveform is "0.58×255", the peak value j3 of the waveform component of the _third waveform is "0.53×255", the fourth waveform The peak value j4 of the waveform component of the waveform is "0.68 × 255", the peak value _j5 of the waveform component of the _fifth waveform is "0.70 × 255", the sixth waveform The peak value _j6 of the waveform component was "1.0×255", and the peak value _jn of the waveform component of the seventh waveform was "0.73×255".

Further, the area _kn of each waveform component 7 is calculated based on the measurement of the waveform component 7 of the image data 50 of the colored pattern 40 expressing the intensity (brightness and darkness) (see FIG. 9). In the waveform graph of FIG. 9, the vertical axis represents the intensity (brightness) of the waveform component 7, and the horizontal axis represents the position (number of dots) of each waveform component 7, as in FIGS. be.

Specifically, the waveform component 7 in each waveform rises beyond the intersection point _dn with the threshold value _cn , passes the peak, descends, and reaches the intersection point en _where it intersects the threshold value _cn again. The integrated value from the minimum value h to the measured value of the waveform component 7 is the area _kn of the waveform component 7 in each waveform.

For example, in the _first waveform, the area k1 of the waveform component ₇ in the _first waveform is the waveform area (shaded area) between the intersections d1 and _e1 with the threshold value c1. In the second waveform, the waveform area (hatched portion) between the intersections d ₂ and e ₂ with the threshold value c ₂ is the area k ₂ of the waveform component 7 in the second waveform. By repeating the above measurement for the number of waveforms, the areas k ₁ to k ₇ from the first waveform to the seventh waveform (FIG. 9) or the areas k ₁ to k 7 from the first waveform to the sixth waveform k ₆ (not shown) is calculated.

As a result, in the waveform graph of FIG. 9, the area (hatched portion) kn of each waveform component 7 is such that the area _k1 of the waveform component of the _first waveform on the right end is "3.31×255" and the second from the right. The area k2 of the waveform component of the _second waveform is "3.24×255", the area k3 of the waveform component of the _third waveform is "2.75×255", the fourth The area k4 of the waveform component of the waveform is "3.14 × 255", the area _k5 of the waveform component of the _fifth waveform is "4.07 × 255", the waveform component of the sixth waveform The area _k6 of the waveform component of the seventh waveform was "6.73×255", and the area k7 of the waveform component of the _seventh waveform was "4.16×255".

Finally, based on the measurement of the waveform component 7 of the image data 50 of the colored pattern 40 expressing the intensity (brightness and darkness), the waveform width f _n , the peak value j _n and the area obtained from each waveform component 7 by the area analysis unit 35 From kn, the score _mn of each waveform component 7 is calculated ₍ see FIG. 10). In the bar graph of FIG. 10, the vertical axis indicates the ratio of the waveform width _fn of each waveform component 7 to the maximum value fn(max) in all waveform widths fn, and the maximum value _{jn (max) in} all peak values _jn . ₎ , the ratio of the area _kn of each waveform component 7 to the maximum value kn _{(max) in} the total area kn _, and the maximum value _{mn ( max)} of each waveform component 7 is represented by _percentage (%), and the horizontal axis represents each waveform component 7 .

The line width difference (for example, thick or thin) of each drawing line 42 in the line drawing pattern 40 is determined by multiplying the waveform width _fn obtained from each waveform component 7, the peak value _jn , and the area _kn . Based on the score _mn of each waveform component 7 obtained by the measurement, the characteristics of each waveform component 7 measured relative to the score _mn are observed.

Specifically, the score _mn of the waveform component 7 in each waveform _is obtained by multiplying the waveform width fn obtained from each waveform component 7 by the score generator 36, the peak value _jn , and the area _kn . It is calculated by

For example, the score m1 of the waveform component 7 in the _first waveform is calculated by multiplying the waveform width f1 obtained from the waveform component ₇ of the _first waveform, the peak value _j1 , and the area k1. be. Similarly, the score _m2 of the waveform component 7 in the _second waveform is obtained by multiplying the waveform width f2 obtained from the waveform component ₇ of the _second waveform, the peak value j2, and the area k2. Calculated. By repeating the above calculation for the number of waveforms, the scores m ₁ to m ₇ (FIG. 10) from the first waveform to the seventh waveform or the scores m ₁ to m 1 from the first waveform to the sixth waveform m ₆ (not shown) is calculated.

As a result, when the first to seventh waveforms are measured, as shown in the bar graph of FIG. 10, the score _mn of _each waveform component 7 is the score m1 is "12", the score _m2 of the waveform component of the second waveform from the right is "13", the score m3 of the waveform component of the _third waveform is "8", the fourth The score m4 of the waveform component of the fifth waveform is " ₁₂ ", the score m5 of the waveform component of the _fifth waveform is "20", the score m6 of the waveform component of the sixth _sixth waveform is "64" ”, and the score m ₇ of the waveform component of the seventh seventh waveform became “21”.

That is, in the present embodiment, among the seven waveform components 7, the score _mn of the waveform component 7 of the primary intensity is "64", which is the maximum value of the score m6 of the waveform component 7 in the _sixth waveform. When converted to 100%, for example, the value "12" of the score m1 of the waveform component 7 in the _first waveform is about 19% of the score m6 of the waveform component ₇ , and the score m The value of ₂ "13" is about 20% to the score m6 of waveform component 7, and the value " ₈ " of score m3 of waveform component ₇ in the _third waveform is 12% to the score m6 of waveform component 7. The score m4 of waveform component 7 in the _fourth waveform "12" is about 19% of the score m6 of waveform component ₇ in the fifth waveform, and the score m5 of waveform component 7 in the _fifth waveform is about 19%. The value "20" is about 31% for the score m6 of waveform component ₇ , and the value "21" for score m7 of waveform component ₇ in the seventh waveform is about 33% for score m6 of waveform component ₇ . % (see FIG. 10).

In this embodiment, the number of drawing lines 42 of the line drawing pattern (color pattern) 40 per digit to be measured is 7 or 6 (see FIG. 4), and only one line is thick. , all others are thin, so for example, when the number of drawing lines 42 to be measured is 7, the score _mn of each waveform component 7 shown in FIG. 10 is calculated. Based on the result, the determination unit 37 determines that the thick line is the waveform component 7 of the sixth waveform, that is, the sixth image line 42 from the right, and the other waveform components 7 of the first to fifth and seventh waveforms. are all thin lines.

Therefore, in the image processing method and image processing system 1 of the present embodiment, rather than comparing the waveform width f ₁ , the peak value j ₁ or the area k ₁ obtained from the waveform component 7 of each object 42, each Comparing the scores m to _n of the stylized lines 42 increases the difference in the score values while accurately reflecting the thickness ratio of the stylized lines 42. Therefore, the actual line width difference of the stylized lines 42 is Even in the case where the .DELTA.

Furthermore, in the present embodiment, in order to convert the discrimination result obtained by comparing the scores m to _n of each stylus 42 into a specific character, the discrimination result and the specific character are associated in advance as shown in Table 1, for example. Predefined tables are available.

Specifically, in the case of this embodiment, by scanning the color pattern 40 (image data 50) from the inside to the outside by the image intensity reading unit 31 (see FIG. 4), seven or six image lines 42 are obtained. 7 (FIG. 6) or 6 (not shown) waveform components 7 corresponding to . Then, by the method described above, based on the calculation results of the scores m ₁ to m ₇ of the seven waveform components 7 (FIG. 10) or the calculation results of the scores m ₁ to m ₆ of the six waveform components 7 (not shown), each A distinction between thick and thin lines of the waveform component 7 can be derived. Then, by applying the obtained combination pattern of thick lines and thin lines to Table 1, it becomes possible to derive a specific character from a pattern consisting of a combination of seven or six drawing lines 42 . Of course, there is no limit to the number of the image lines 42 forming the colorful pattern 40 or the number of the waveform components 7 acquired by the image intensity reading unit 31, and arbitrary n image lines 42 and arbitrary n waveforms A specific character can also be derived by calculating scores m ₁ to m _n for a pattern consisting of a combination of components 7 .

REFERENCE SIGNS LIST 1 image processing system 2 image acquisition device 20 imaging unit 21 transmission unit 3 image processing device 30 reception unit 31 image line intensity reading Part 32... Scanning line indication part 33... Waveform width analysis part 34... Primary intensity analysis part 35... Area analysis part 36... Score generation part 37... Discrimination part 4...・ Base material 40 ... Line drawing pattern (color pattern)
41 ... two-dimensional code (QR code (registered trademark))
42... Drawing line 5... Image data 50... Line drawing pattern image data 51... Two-dimensional code (QR code (registered trademark)) image data 52... Scanning line 6... - Arrangement data of scanning lines 7: Primary intensity (waveform component)
70 Waveform width 71 Peak value 72 Area 73 Threshold 8 Score

Claims (18)

An image processing method for determining a drawing line having at least a first line width from a line drawing pattern including two or more drawing lines having different line widths printed on a base material,
Acquiring image data of a line drawing pattern including two or more lines of different line widths printed on a base material by an imaging unit;
a step of obtaining, as a waveform component, a primary intensity of each image line along a scanning line crossing each image line from the image data of the line drawing pattern by an image line intensity reading unit;
obtaining a waveform width of a waveform component corresponding to each drawing line at a certain primary intensity threshold value from the waveform component of the primary intensity by the waveform width analysis unit;
obtaining a peak value of the primary intensity of the waveform component corresponding to each image line above the threshold from the waveform component of the primary intensity by the primary intensity analysis unit;
obtaining the area of the region above the threshold value and surrounded by the waveform components corresponding to each drawing line from the waveform component of the primary intensity by the area analysis unit;
A score representing the line width of each image line along the scanning line is obtained by multiplying the waveform width value, the primary intensity peak value, and the area value of the waveform component of each image line by the score generating unit. and determining, by a determining unit, an object line having at least a first line width from the score of each image line. The drawing line having the first line width is the drawing line having the thickest line width among two or more drawing lines having different line widths, or the drawing line having the thinnest line width among two or more drawing lines having different line widths. 2. The image processing method according to claim 1, wherein the object line has a line width. 3. The image processing method according to claim 1, wherein said determining unit further includes a step of determining an image line having a second line width different from said first line width. 4. The image processing method according to any one of claims 1 to 3, wherein the threshold value for each image line is corrected according to the brightness of each corresponding image line based on the image data. . The image data further includes image data of a specific code printed on the base material acquired by the photographing unit, and the arrangement of the scanning lines with respect to the line drawing pattern is determined by a scanning line designating unit, 5. The image processing method according to any one of claims 1 to 4, wherein the code is determined based on the image data of the specific code. 6. The image processing method according to claim 5, wherein said specific code is a two-dimensional code. 7. An image processing method according to any one of claims 1 to 6, wherein said scanning lines are defined to traverse each image line at the same angle. 8. The image processing method according to any one of claims 1 to 7, wherein the line drawing pattern is a colored pattern. 9. The image processing method according to any one of claims 1 to 8, further comprising the step of converting the image data into 256-gradation gray scale after acquiring the image data. An image processing system for determining a drawing line having at least a first line width from a line drawing pattern including two or more drawing lines having different line widths printed on a base material,
an imaging unit that acquires image data of a line drawing pattern including two or more lines with different line widths printed on a base material;
an image acquisition device comprising a transmission unit that transmits the image data to an image processing device by wire or wirelessly; and a reception unit that receives the image data transmitted from the image acquisition device;
an image line intensity reading unit that obtains, as a waveform component, a primary intensity of each image line along a certain scanning line crossing each image line from the image data of the line drawing pattern;
a waveform width analysis unit that obtains, from the waveform components of the primary intensity, waveform widths of waveform components corresponding to each drawing line at a certain threshold value of the primary intensity;
a primary intensity analysis unit that obtains, from the waveform components of the primary intensity, a peak value of the primary intensity of the waveform component that is above the threshold value and that corresponds to each drawing line;
an area analysis unit that obtains the area of a region above the threshold value and surrounded by waveform components corresponding to each drawing line from the waveform component of the primary intensity;
generating a score representing the line width of each streak along the scan line by multiplying the waveform width value, the primary intensity peak value and the area value of the waveform component of each streak; and a determination unit configured to determine a drawing line having at least a first line width from the score of each drawing line. The drawing line having the first line width is the drawing line having the thickest line width among two or more drawing lines having different line widths, or the drawing line having the thinnest line width among two or more drawing lines having different line widths. 11. The image processing system according to claim 10, wherein the object line has a line width. 12. The image processing system according to claim 10, wherein the discrimination unit further discriminates an image line having a second line width different from the first line width. 13. The image processing system according to any one of claims 10 to 12, wherein the threshold for each object is corrected according to the brightness of each corresponding object based on the image data. . The image data further includes image data of a specific code printed on the base material acquired by the imaging unit, and based on the image data of the specific code, the scanning line for the line drawing pattern. 14. An image processing apparatus according to any one of claims 10 to 13, further comprising a scanning line indicator for determining the placement of the . 15. The image processing system according to claim 14, wherein said specific code is a two-dimensional code. 16. An image processing system as claimed in any one of claims 10 to 15, wherein the scan lines are defined to traverse each image line at the same angle. 17. The image processing system according to any one of claims 10 to 16, wherein the line drawing pattern is a colored pattern. 18. The image processing system according to any one of claims 10 to 17, wherein said image data is converted into 256-gradation gray scale.

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