KR100927859B1 - Determination of Abnormal State of Slab Management Number Marking Device Using Digital Image Processing Technique - Google Patents

Abstract

An abnormal state determination method of a slab management number marking apparatus using a digital image processing technique of the present invention forms a string by marking the slab management number on the slab by a marking apparatus, and includes a common region including the string and a background region other than the string. After extracting only the text area portion from the area, the value of the height, width and width / height ratio of the character string of the text area portion and the reference value having the height, width and width / height ratio value of the character string corresponding to each of the values are compared. Marking device by identifying the abnormal condition of the slab management number marking device and the remaining amount of paint by providing a method of determining whether there is an abnormal state due to lack of paint remaining and abnormal state due to nozzle abnormality of the marking device. There is an advantage that can be managed efficiently.

Description

METHOOD FOR CHECKING ERROR OF SLAB ADMINISTRATION NUMBER MARKING DEVICE BY USING DIGITAL IMAGE PROCESSING}

The present invention relates to a method for determining an abnormal state of a marked symbol or the like using a digital image processing technique. More particularly, the present invention relates to an abnormality of a nozzle state of a marking apparatus for marking a slab management number using a digital image processing technique. The present invention relates to a method of determining whether an abnormal state is caused by a lack of paint.

In the current steel industry, it is determined by the manager whether the slab control number marking device is abnormal.In general, the marking is left unattended for 2 to 3 hours after the abnormality of the marking device. It is a fundamental cause of lowering the recognition rate of control number recognition system.

 Digital Image Processing (DIP) is a projection profile analysis method that is mainly used to separate individual characters from a string with strong intensity in a limited space. The method of using the projection profile analysis generally proceeds as follows.

First, a color image is converted into a brightness image, and a brightness image is converted into a binary image.

Second, the binary image data is regarded as a two-dimensional matrix, and data is added in the vertical or horizontal direction, and the data value added in the vertical direction represents a vertical projection profile (hereinafter referred to as "VPP"), and is added in the horizontal direction. The data value represents a horizontal projection profile ("HPP").

Third, a sudden change in coordinate values is detected in the vertical projection profile VPP or the horizontal projection profile HPP.

Such a method exists within a limited space, and when there is no other noise having characteristics similar to a character string, the principle and structure are very simple compared to other character string detection algorithms, and thus, the method is used to detect a specific target.

However, since the result of the 'projection' process loses information on the two-dimensional space of the projected portion, there is a disadvantage that the detection performance of the object is deteriorated when the noise is severe.

The technical problem to be solved by the present invention is to extract only the slab management number from the entire image of the slab is not fixed position of the slab, the binarized horizontal projection profile (HPP) and vertical projection profile ( By analyzing the VPP), there is provided a method for determining whether or not an abnormality of the marking state with respect to the slab management number due to the nozzle abnormality of the marking apparatus.

In addition, the technical problem to be solved by the present invention is to perform the operation of separating each individual character from the extracted character string of the slab management number, and the binarized horizontal projection profile (HPP) and vertical projection for the separated individual characters By analyzing the profile (VPP), there is provided a method for determining whether an abnormality in the marking state for the slab control number due to insufficient paint remaining.

In order to determine the abnormal state of the slab management number marking apparatus using a digital image processing technique according to the present invention for forming the technical problem, by marking the slab management number on the slab by the marking device to form a string, the string and the string After extracting only the text area portion from the common area including the background area other than the above, the height, width and width / height ratio value of the character string of the character area portion and the height, width and width / height of the character string corresponding to each of the values By comparing a reference value having a ratio value, there is provided a method for determining whether an abnormal state due to a nozzle abnormality of the marking apparatus and an abnormal state due to insufficient paint remaining.

The present invention has the advantage that it is possible to efficiently manage the marking device by grasping the nozzle abnormal state and the remaining paint state of the slab management number marking device to inform the administrator.

Hereinafter, specific embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 shows photographing a slab management number marked by a marking apparatus according to the present invention with a camera.

Referring to FIG. 1, the present invention includes a marking device 110, a marking device nozzle 115, a slab 120, a slab management number 125, and a camera 130. Paint is embedded in the marking device 110, and the paint is sprayed to the front surface of any one side of the hot slab 120 freshly made in the steel mill through the outlet of the marking device nozzle 115 to manage the slab. Mark number 125. The camera 130, when the marking device 110 moves to the side after marking the slab management number 125 on the slab 120, the slab management number 125 is marked on the slab 120 to mark the slab Get the full image.

2 illustrates extracting only a text area portion from the entire slab image according to the present invention.

2 and 1, the entire slab image 210 includes not only the slab 120 but also other backgrounds, and the slab letters are slightly changed in position for each slab to be marked. However, since it does not deviate from the common area 220 statistically, image processing is started from the common area 220 instead of the entire slab image 210 to extract the text part.

Hereinafter, how to perform image processing in detail from the common area 220 will be described in detail.

The present invention utilizes the Otsu's method, which is widely used when evolving a brightness image as a binarization method to implement binarization image processing.

First, a method of obtaining the upper and lower boundary (y-coordinate) boundary area of the character area using the horizontal projection profile (HPP) will be described.

After extracting the binarized image to extract the character portion from the common region 220, a horizontal character region is extracted using a horizontal projection profile (HPP). In other words, the image data can be viewed in the form of a two-dimensional matrix to perform a row sum.

E.g,

일 경우, y-index가 1,2,3,4로 주어질 경우 y(1)= 0 +1 +2 +3 =6 (1행의 각각의 값을 더하는 row sum을 수행)의 값을 가지며, 마찬가지 방식으로 각각은 y(2)= 15, y(3)= 18, y(4)= 6 의 값을 갖는다. 여기서 상기 값들은 글자부분을 표현하는 백색(이진화 값 1) 픽셀의 개수를 의미한다.A =

If y-index is given as 1,2,3,4, it has the value of y (1) = 0 +1 +2 +3 = 6 In a similar manner each has a value of y (2) = 15, y (3) = 18, y (4) = 6. Here, the values refer to the number of white (binarization value 1) pixels representing the character portion.

In general, the HPP is expressed as Equation 1 below.

Here, as shown in FIG. 2, width represents a width in the horizontal direction (x axis), and height represents a height in the vertical direction (y axis).

3 is a graph illustrating a process of extracting the upper and lower direction (y-coordinate) letter region parts and performing image processing.

Referring to FIG. 3, in order to convert the image into a binary image represented by black (0) and white (1), the X and Y axes are displayed in pixels (pixels, unit dpi). The graph is shown. In the graph below, the X-axis represents the Y-axis index of the actual image, and the Y-axis represents the result of performing row sum as described in the above example. The first displayed area of the graph represents the approximate y-top of the string, and the second displayed area represents the approximate y-bottom of the string. A boundary area can be obtained.

4 shows a leveling operation of HPP (y) using a graph obtained by image processing.

Referring to FIG. 4, for example, when an experimentally determined constant threshold value is 10, binarization 1 when having a value greater than the threshold value, and binarization 0 when having a number greater than or equal to the threshold value, is 0. The graph shows the results of binarization. Here, the letter boundary area and the lowest point of the vertical height of the string in the vertical direction of the string through the coordinate values of the leftmost part (about 35 points on the X axis) and the rightmost part (about 110 points on the X axis) with respect to the long axis of the ellipse. It is possible to accurately determine the letter boundary area of the height (y-bottom).

Similarly to the method of finding the upper and lower letter boundary regions using the horizontal projection profile HPP, the method of finding the character boundary regions in the left and right directions (x-coordinates) using the vertical projection profile VV will be described below. . At this time, use the image cut into the upper and lower letter boundary area.

E.g,

일 경우, x-index가 1,2,3,4로 주어질 경우 x(1)= 0 +4 +1 +2 =7 (1열의 각각의 값을 더하는 column sum을 수행)의 값을 가지며, 마찬가지 방식으로 각각은 x(2)= 16, x(3)= 20, x(4)= 4 의 값을 갖는다. 여기서 상기 값들은 글자부분을 표현하는 백색(이진화 값 1) 픽셀의 개수를 의미한다.A =

If x-index is given as 1,2,3,4, it has the value of x (1) = 0 +4 +1 +2 = 7 Each has a value of x (2) = 16, x (3) = 20 and x (4) = 4. Here, the values refer to the number of white (binarization value 1) pixels representing the character portion.

In general, the VPP is represented by Equation 2 below.

Here, as shown in FIG. 2, width represents a width in the horizontal direction (x axis), and height represents a height in the vertical direction (y axis).

5 is a graph illustrating a process of image processing by extracting a text area portion in a horizontal direction.

Referring to FIG. 5, the X axis in the graph represents a result of performing a column sum in the manner described in the above example.

6 illustrates a leveling operation of VPP (x) using a graph obtained by image processing.

Referring to FIG. 6, for example, when an experimentally determined constant threshold value is 5, binarization 1 when having a value greater than the threshold value, and binarization 0 when having a number greater than or equal to the threshold value, the binarization value is 0. FIG. The graph shows the results of binarization. Here, the character boundary area and the end point of the horizontal start point (x-start) of the character string through the coordinate values of the leftmost part (approximately 210 points on the X axis) and the rightmost part (approximately 710 points on the X axis) with respect to the long axis of the ellipse. character boundary of x-end) can be determined accurately.

Figure 7 shows the normal state and abnormal state of the binarized slab management number.

Referring to FIG. 7, 701 denotes a normal marking state, and 702 denotes a state in which marking characters are flowed out by irregularly flowing paint over nozzles having no nozzle wear or nozzle life. 703 shows a state in which most of the characters are lost when the amount of paint remaining is insufficient, which shows the state immediately after the marking, and is hardly considered to be lost by heat. The paint generally uses water-based paint, and the amount of paint consumed varies depending on the amount of work. Therefore, it is difficult to accurately predict the remaining amount of water shortly automatically, and the manager has to manually check the remaining amount of paint based on experience.

On the other hand, the slab management number should be marked for slabs with different front sizes, so that the slab control number is a reference value with a range of heights, widths, and width / height ratios of the string to be marked so that normal marking is possible for narrow slabs. It is predetermined.

It can be seen that the control number of the normal marked state 701 has a value of a substantially constant height, width and width / height ratio when compared to the reference value when the character string is extracted through the profile analysis.

On the other hand, in case of the abnormal state (701, 702), it can be seen that when compared to the reference value when extracting the character string through the profile analysis, it does not have the values of normal height, width, and width / height ratio.

Based on the above description, the following summary conclusion can be made.

First, the height, width, and width / height ratio of the string of the extracted slab management number do not belong to the range defined by the reference value, or the value of the white pixel (binary value 1) representing the character string by binary image is the common value. If it does not reach a predetermined range of reference area values for the total area of the area, it can be determined that the abnormal state due to insufficient paint remaining.

Second, if it is determined that the lack of paint state is not abnormal, Calculate the HPP and VPP, and proceed with the process of separating the individual characters constituting the respective character strings. By judging whether or not there is, it is possible to determine whether or not normal marking has been made.

Third, when the result of the marking state of the character string is determined to be an abnormal state by moving out of the range of the reference value, it has a function of detecting and notifying the corresponding administrator through an alarm device such as an alarm, and so on. Repair and maintenance work can be performed quickly.

In the above description, the technical idea of the present invention has been described with the accompanying drawings, which illustrate exemplary embodiments of the present invention by way of example and do not limit the present invention. In addition, it is apparent that any person having ordinary knowledge in the technical field to which the present invention belongs may make various modifications and imitations without departing from the scope of the technical idea of the present invention.

1 shows photographing a slab management number marked by a marking apparatus according to the present invention with a camera.

2 illustrates extracting only the text area portion from the entire slab image according to the present invention.

3 is a graph illustrating a process of extracting the upper and lower direction (y-coordinate) letter region parts and performing image processing.

4 shows a leveling operation of HPP (y) using a graph obtained by image processing.

5 is a graph illustrating a process of image processing by extracting a text area portion in a horizontal direction.

6 illustrates a leveling operation of VPP (x) using a graph obtained by image processing.

Figure 7 shows the normal state and abnormal state of the binarized slab management number.

Claims (8)

A method of determining an abnormal state of a marked symbol using a digital image processing method, (a) marking the slab management number on the slab by the marking device to form a character string; (b) extracting only a text area portion from a common area including the text string and a background area other than the text string; (c) comparing a height, width, and width / height ratio value of the character string of the character area portion with a reference value having a height, width, and width / height ratio value of the character string corresponding to each of the values; And (d) determining that the height, width, and width / height ratio of the extracted character string are abnormal due to insufficient paint remaining when the value does not fall within the range defined by the reference value; After obtaining a horizontal projection profile (HPP) and a vertical projection profile (VPP) from the binary image of the character string, the character string when the height, width, and width / height ratio value of the character string exceed the corresponding range of the reference value. Determining that each character constituting the attached to each other comprising the step of determining that the abnormal state due to the abnormality of the nozzle of the marking device, characterized in that the abnormal state determination method of the slab management number marking device using a digital image processing technique. delete According to claim 1, The abnormal state due to the nozzle abnormality of the marking device  And determining the abnormal state of the slab management number marking apparatus by using the digital image processing technique. delete delete The method of claim 1, wherein the horizontal projection profile (HPP) A digital image processing technique is characterized by obtaining a text boundary region of a y-top and a y-bottom height in a vertical direction of the string by using a coordinate value of binarization. Determination of abnormal state of the slab management number marking device. The method of claim 1, wherein the vertical projection profile (VPP) The slab using the digital image processing technique, characterized by obtaining the character boundary region of the start point (x-start) and the character boundary region of the end point (x-end) in the horizontal direction of the string by using the coordinate value of the binarization operation. How to determine the abnormal state of control number marking device. The method of claim 1, The abnormal state of the slab management number marking apparatus using a digital image processing technique, characterized in that it further comprises the step of notifying the administrator of the abnormal state due to the lack of the remaining amount of paint and the abnormal state due to the nozzle abnormality. Discrimination method.

Images