KR101940519B1 - Apparatus and method for automatic water level measurement - Google Patents

Abstract

An automatic water level measuring device and method are provided that irradiate a reference light pattern to a pattern irradiation object such as a pier or a bank, input a light pattern in real time through an image acquisition device, analyze / process the image, and automatically measure the current water level do. The proposed apparatus includes a light pattern irradiating unit for irradiating a pattern irradiation object with a reference light pattern, an image acquiring unit acquiring an image including a reference light pattern irradiated on the pattern irradiating object, and an image acquired through the image acquiring unit, And a water level analysis unit for measuring the water level.

Description

[0001] Apparatus and method for automatic water level measurement [

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to an automatic level measuring apparatus and method, and more particularly, to an apparatus and a method for automatically measuring a level using an optical pattern irradiation.

Conventionally, the water level of a river was measured by installing a water level table on a pier or a bank installed in a river, and then checking the scale of the water level table through an image acquisition device.

However, there is a concern such as contamination, damage and loss due to changes in the external environment, especially in the case of the water table installed outside.

Also, if the visibility can not be secured due to smog, fog, smoke, etc., the water table itself may not be recognized through the image acquisition device. In addition, installation of additional facilities may be necessary in situations where it is difficult to install a lighting and near-vision acquisition system for water mark recognition.

To solve this problem, several inventions have been introduced to automatically measure river water level. There is a method of measuring the height of rivers by using pixel gradient based image processing without using a water level table and a method of measuring the water level by FFT method using water characteristic frequency.

Korean Patent Laid-Open No. 10-2012-0011505 discloses a method of measuring pollution in a surveillance area, providing a level measurement method corresponding thereto, configuring the system as an embedded board and providing wired / wireless communication, Is shortened.

The aforementioned Korean Patent Laid-Open Publication No. 10-2012-0011505 is a passive method of recognizing and processing a neck board (water mark) installed on an object (a bank, a bridge, etc.).

Korean Patent Laid-Open No. 10-2014-0023131 discloses a method of measuring the water level of a river based on image data including a QR code and a river installed on a pier or a bank and measuring the water level of the river using an unmanned contactless method The contents which can utilize the fixed surveillance camera as it is are described.

In Korean Patent Laid-Open No. 10-2008-0013442, since the change in the height of the liquid can be known through the contrast of the image itself without buried in a separate standard such as a water table, the water level table due to external factors such as natural disasters And the liquid level can be measured without the problem of loss or damage of the standardizer.

SUMMARY OF THE INVENTION The present invention has been proposed in order to solve the above-mentioned problems of the prior art, and it is an object of the present invention to irradiate a pattern irradiation object such as a pier or a bank with a reference light pattern, input a light pattern in real time through an image acquisition device, The present invention also provides an automatic level measuring apparatus and method for automatically measuring a level of a fluid.

According to another aspect of the present invention, there is provided an automatic level measuring apparatus comprising: a light pattern irradiating unit for irradiating a pattern irradiated object with a reference light pattern; An image acquiring unit acquiring an image including a reference light pattern irradiated to the pattern irradiated object; And a water level analyzer for analyzing the image acquired through the image acquisition unit and measuring the current water level.

Wherein the level analyzer comprises: a light pattern output unit for providing a reference light pattern to be irradiated to the light pattern irradiating unit; A light pattern generator for generating a reference light pattern to be irradiated on the basis of a shape of a plurality of previously stored reference light patterns and providing the reference light pattern to the light pattern output unit; An image input unit for receiving the image acquired by the image acquisition unit; And an image processor for processing the input image to measure the current water level.

The level analyzer may further include a user interface unit, and the image processor may process the image of interest set through the user interface unit in the image input through the image input unit and measure the current water level based on the image.

The image processing unit binarizes an image in the ROI, performs pattern edge detection on the binarized image, performs labeling of the unit pattern of the reference light pattern, and labels the reference pattern on the X- and Y- Performing an interpolation on an error region by comparing each of the clustered regions, generating a virtual watermark table including virtual horizontal lines based on the interpolated result, The current water level can be predicted based on the current water level.

The light pattern generator may finely adjust the pattern pattern selected by the user interface unit to coincide with the pattern irradiation object, and then provide the light pattern to the light pattern output unit.

The level analyzer may further include a transmitter for outputting the current level measured by the image processor to the outside.

The reference light pattern may be shaped differently depending on the external shape, width, height, and distance of the pattern irradiation object.

The reference light pattern includes a plurality of unit patterns, and the center distances between the unit patterns may have a predetermined interval.

The light pattern irradiating unit may include a laser projector or an optical sensor.

The automatic level measuring method according to a preferred embodiment of the present invention includes the steps of: the light pattern irradiating unit irradiating the pattern irradiated object with a reference light pattern; An image acquiring unit acquiring an image including a reference light pattern irradiated to the pattern irradiated object; And analyzing the acquired image to measure a current water level.

Wherein the step of measuring the current level comprises: generating a reference light pattern to be inspected based on a shape of a plurality of previously stored reference light patterns and providing the reference light pattern to the light pattern inspection unit; Receiving an image obtained by acquiring the image; And processing the input image to measure the current water level.

In the step of measuring the current water level, the user can perform an image processing on a region of interest set through the user interface unit in the input image, and measure the current water level based on the image.

Wherein the step of measuring the current water level comprises: binarizing an image in the ROI; Performing pattern edge detection on the binarized image to perform labeling of the unit pattern of the reference light pattern; Clustering and labeling the label regions having similar coordinates for the X axis and the Y axis; Comparing each of the clustered regions and interpolating an error region; Generating a virtual watermark table including virtual horizontal lines based on the interpolated result; And predicting the current water level based on the virtual water table.

The step of generating the reference light pattern to be inspected and providing the reference light pattern to the light pattern inspection unit may finely adjust the pattern shape selected by the user interface unit to coincide with the pattern inspection object, .

The step of measuring the current water level may further include outputting the measured water level to the outside.

According to the present invention having such a configuration, a water level measurement can be automatically performed by generating a virtual water level table from an input pattern by actively irradiating a pattern to an object.

Such an active pattern illumination method has the advantage that it can be robustly recognized even in a naked-eye environment (light smoke or foggy environment), can be used at night, and requires no separate illumination.

Conventionally, a manual type in which a water level table installed on a pier or a bank or a recognition device installed separately is inputted and processed through a camera, but the present invention can be used in an environment where a water level table is not installed on a pier or a bank, Cost is low.

1 is a configuration diagram of an automatic level measuring apparatus according to an embodiment of the present invention.
FIG. 2 is a diagram comparing the magnifications of the unit patterns of the reference light pattern shown in FIG.
3 is a configuration diagram of the water level analysis unit shown in FIG.
4 is a network configuration diagram of an automatic level measuring apparatus according to an embodiment of the present invention.
5 is a flowchart for explaining a process of irradiating the light pattern in the embodiment of the present invention.
6 is a flowchart illustrating an automatic level measurement method according to an embodiment of the present invention.
Figs. 7 to 14 are views employed in the description of Fig.

While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail.

It should be understood, however, that the invention is not intended to be limited to the particular embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

The terminology used in this application is used only to describe a specific embodiment and is not intended to limit the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In the present application, the terms "comprises" or "having" and the like are used to specify that there is a feature, a number, a step, an operation, an element, a component or a combination thereof described in the specification, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the relevant art and are to be interpreted in an ideal or overly formal sense unless explicitly defined in the present application Do not.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In order to facilitate the understanding of the present invention, the same reference numerals are used for the same constituent elements in the drawings and redundant explanations for the same constituent elements are omitted.

The present invention employs a method in which a light irradiation apparatus is provided at the same position or at a different position from the image acquisition apparatus and the reference light pattern is directly irradiated to the pier or a bank instead of installing a water level table on a pier or a bank. This is to eliminate the problems such as contamination, damage and loss of the water table of the existing system, and to make the water level measurement more accurate even in the case of the visible range restriction due to the smog due to the use of the mark pattern which is much stronger than the existing water level table. In addition, the present invention utilizes a ratio method between internal patterns so that a water level can be measured irrespective of the installation distance between a pattern inspection object such as a pier or a bank, and an image acquisition device.

That is, since the present invention utilizes a specific reference light pattern for automatic level measurement, it is very robust against external noise environments such as pier porosity and visual distance uncertainty. Further, since the present invention uses a ratio comparison between respective regions in a light pattern, it has a feature of being able to offset a problem of increasing or decreasing a pattern size according to a distance change with a pattern irradiation object.

FIG. 1 is a configuration diagram of an automatic level measuring apparatus according to an embodiment of the present invention, and FIG. 2 is a diagram comparing magnifications between unit patterns of the reference light pattern shown in FIG.

The automatic level measuring apparatus according to the embodiment of the present invention includes a light pattern irradiating apparatus 10, an image acquiring apparatus 20, and a water level analyzing unit 50.

The light pattern irradiating apparatus 10 irradiates the pattern irradiating object 40 such as a pier or a bank with a reference light pattern 30. [ Here, the reference light pattern is different in shape (that is, array size of the pattern) depending on the external shape, width, height, distance, and the like of the pattern irradiation object 40.

As the distance d between the unit patterns in the reference light pattern incident on the image acquiring device 20 increases, the resolution of the water level measurement decreases. Conversely, as the distance d between the unit patterns in the reference light pattern incident on the image acquiring device 20 approaches, the resolution increases. Accordingly, it is preferable that the distance T _d between the unit patterns in the reference light pattern 30 irradiated on the pattern irradiation object 40 has a constant interval.

The light pattern irradiating apparatus 10 may be composed of, for example, a laser projector or an optical sensor.

The light pattern irradiating apparatus 10 is an example of the light pattern irradiating unit described in the claims of the present invention.

The image acquiring device 20 acquires a light pattern image irradiated on the pattern irradiating object 40 such as a pier or a bank. Of course, the image acquired by the image acquisition device 20 may include only the reference light pattern 30, or the reference light pattern 30 and the image of water may be present together.

The image acquisition device 20 may be an image sensor such as a camera.

The image acquisition device 20 is an example of the image acquisition unit described in the claims of the present invention.

The level analyzer 50 analyzes the optical pattern image acquired through the image acquiring device 20 and measures the current water level.

On the other hand, the shape of each unit pattern in the reference light pattern 30 is defined in advance as shown in Fig. In addition, since the area of each unit pattern is reliably recognized by comparing the ratio with the adjacent unit patterns, even if a change in the area of the unit pattern occurs largely according to the distance D, there arises a problem in processing and recognizing the entire pattern Do not.

However, since the distance d between the unit patterns in the reference light pattern 30 incident on the image acquisition device 20 determines the resolution of the final water level measurement result, the unit patterns in the image processing overlap each other The closer the distance between the two unit patterns is, the better.

In FIG. 1, the light pattern irradiating apparatus 10, the image acquiring apparatus 20, and the water level analyzing unit 50 can be interlocked into a single system through the enclosure 60.

In Fig. 1, H means the original height of the pier, and ph means the height from the pier to the water level. D represents the distance between the pattern irradiated object 40 and the level analysis unit 50. [

3 is a configuration diagram of the water level analysis unit shown in FIG.

The water level analysis unit 50 includes a light pattern output unit 510, a light pattern generation unit 520, a user interface unit 530, a database 540, a transmission unit 550, a timer 560, an image input unit 570 And an image processing unit 580. [

The light pattern output unit 510 provides a reference light pattern to the light pattern irradiating apparatus 10. Accordingly, the light pattern irradiating apparatus 10 irradiates the reference light pattern from the light pattern outputting section 510 to the pattern irradiating object 40 such as a pier or a bank.

The light pattern generating unit 520 generates a reference light pattern to be irradiated to the pattern irradiating object 40 and provides the same to the light pattern outputting unit 510. At this time, the reference light pattern to be irradiated to the pattern irradiation object 40 is selected from various pattern types stored in the database 540 through the user interface unit 530 in accordance with the width, distance, and the like of the pattern irradiation object 40.

That is, the light pattern generator 520 fine-adjusts the pattern pattern selected by the user interface unit 530 to exactly match the pattern irradiated object 40, and then provides the light pattern to the light pattern output unit 510.

The user interface unit 530 can selectively input a reference light pattern to be irradiated to the pattern irradiation object 40. [

Meanwhile, the user interface unit 530 may set an ROI in the optical pattern image acquired through the image acquisition device 20. [

The database 540 stores various types of reference light patterns. Accordingly, the user interface can select one of various types of reference light patterns stored in the database 540 based on the width, distance, and the like of the pattern inspection object 40.

The image input unit 570 receives the optical pattern image acquired by the image acquisition device 20 (that is, the image including the reference light pattern) through a cable for image transmission or a network.

The timer 560 adjusts the output time interval of the transmission unit 550 that transmits the input image frame rate and the final processed level measurement result.

The image processing unit 580 performs image processing on the ROI set through the user interface unit 530 on the image received through the image input unit 570. [ Then, the image processing unit 580 finally calculates the predicted water level and outputs it to the transmission unit 550. Accordingly, the transmission unit 550 sends the final predicted water level to the integrated control center through a network or the like.

4 is a network configuration diagram of an automatic level measuring apparatus according to an embodiment of the present invention.

The automatic level measuring apparatus can transmit the predicted water level analyzed by the water level analysis unit 50 to the integrated control center 70 through the network 80 such as the Internet.

Accordingly, the integrated control center 70 can perform integrated monitoring for river and flow volume check.

5 is a flowchart for explaining a process of irradiating the light pattern in the embodiment of the present invention.

First, the user interface unit 530 selects one of various patterns stored in the database 540 according to the external shape, width, height, distance, and the like of the pattern inspection object 40. Then, the light pattern generator 520 generates a reference light pattern in which the selected pattern form is adjusted so that the height and width of the pattern form exactly match the pattern object 40 (S10). At this time, the distance (T _d ) between the unit patterns according to the pattern and the distance (D) between the pattern inspected object 40 are adjusted together and stored in the database 540 (see Table 1 below) ).

Pattern Num. Region Distance in Pattern (T _d : pixels) Region Distance in Pattern (T _d : cm)  Distance to Bridge (D)       One      10 pixels         1cm           20m       One      20 pixels         2cm           15m       One      30 pixels         3cm           10m       2      12 pixels        1.2cm           18m       2      15 pixels        1.5cm           14m       2      18 pixels        1.8cm           10m      ...            ...          ...            ...

Table 1 above shows the distance relation table between the intra-pattern area distance and the bridge pier. The distance T _d between the unit patterns in the reference light pattern is represented by pixels in the image, and is converted into cm in the actual distance measurement. The database 540 has a mapping table therefor.

The light pattern generator 520 sends the generated reference light pattern to the light pattern output unit 510. Accordingly, the light pattern output unit 510 irradiates the pattern irradiated object 40 with the light pattern through the light pattern irradiating apparatus 10 (S20).

FIG. 6 is a flowchart for explaining an automatic level measurement method according to an embodiment of the present invention, and FIGS. 7 to 14 are views employed in the description of FIG.

First, as shown in Fig. 5, the pattern irradiation object 40 is irradiated with the light pattern.

Next, the image input unit 570 receives the optical pattern image acquired by the image acquisition device 20 through a cable for image transmission or a network. That is, the image input unit 570 receives the light pattern image irradiated from the image acquisition device 20 on the pattern irradiation object 40 in real time on a frame-by-frame basis. The image input unit 570 sends the received optical pattern image to the image processing unit 580.

Accordingly, the image processing unit 580 receives the ROI set in the user interface unit 530 (S30). That is, in order to reduce the measurement error due to the image processing time and the error, ROI (Region of Interest) 5 as shown in FIG. 7 is inputted only to the light pattern irradiated region of the input image.

The image processing unit 580 performs the following image processing on the ROI set through the user interface unit 530 in the image received through the image input unit 570 to calculate the final predicted water level .

For example, the image processor 580 acquires a pattern image within the region of interest (S40). Here, the pattern image means an image composed of a reference light pattern existing in the region of interest 5.

Then, the image processor 580 binarizes the pattern image using adaptive thresholding to obtain a binarized image as shown in FIG. 8 (S50). For example, a morphology (CLOSE) operation is performed on a set ROI based on a kernel (for example, a 5 * 5 kernel) to remove noise, and then an adaptive threshold process is performed. Here, the elimination of noise is necessary to eliminate unnecessary scattered spot areas in later labeling. The adaptive threshold value T _{x , y} is a weighted average calculated by assigning Gaussian weight values to predetermined blocks (for example, 11 * 11 blocks) around the (x, y) pixels of the ROI image.

After the pattern edge detection, the image processing unit 580 labels each area in the pattern to obtain a labeled image as shown in FIG. 9 (S60). Labeling refers to attaching the same number of labels to adjacent pixels and assigning different numbers to other elements that are not connected. In other words, in order to perform labeling of a unit pattern based on a contour, for example, Suzuki's Border Following Algorithm (BFA) (S. Suzuki and K. Abe, " Topological structural analysis of digitized binary images by border following , Computer Vision, Graphics, and Image Processing, vol. 30, num. 1, pp. 32-46, 1985). BFA is used to calculate the label area, perimeter, topology structure, etc. based on the pixel unit connection element in the image. For reliable area labeling with robustness in the false detection region, for example, after applying the BFA technique, an Iterative end-point Fit technique (U. Ramer, "An iterative procedure for the polygonal approximation of plane curves" Douglas & T. Peucker, " Algorithms for the Number of Points Required to Represent a Digitized Line or Its Caricature ", The Canadian Cartographer < RTI ID = 0.0 > , vol. 10, num. 2, pp. 112-122, 1973.), and selectively labeling only three or four areas with the same number of corners as the unit pattern. This allows us to know the center coordinates of each label and the size of the area.

Then, the image processing unit 580 performs clustering (clustering) on the X-axis and the Y-axis, respectively, and groups them by groups having similar X-coordinate values or Y-coordinate values (S70). In other words, the start coordinates of each unit pattern input to the image input unit 570 through the image acquisition device 20 are not all the same with respect to the Y coordinate. Accordingly, the order of the labeled areas is not listed in order from left to right or top to bottom as shown in FIG. Therefore, label regions having similar Y coordinates are clustered and ordered. A similar Y coordinate reference is obtained by finding an average distance d between each unit pattern in one image frame, then selecting one arbitrary unit pattern and referring to the area located within the upper and lower (1/2) d with respect to the center coordinates of the corresponding label do. Therefore, all the unit patterns in this area are processed in the same cluster and re-labeled. All of the unit patterns except for the re-labeled unit pattern are selected, and the same process is repeated to group all the unit patterns. The labels are rearranged in order by sorting based on the Y coordinates of the clustering labels. Although the above description has been made on the basis of the Y coordinate alone, the same process is also performed on the basis of the X coordinate. As a result, a re-ordered label is obtained based on the X and Y coordinates as shown in FIG.

Then, the image processing unit 580 compares the clustered regions along the Y-axis direction, and performs interpolation on the error region (S80). In other words, interpolation is performed on the missing unit pattern area due to errors in the reference light pattern inspection process or the image acquisition process. The reliability of the currently processed label region is very high because we have already removed the error region through preprocessing such as Morphology (CLOSE) and Iterative End-point Fit technique. However, as shown in FIG. 2, the reliability of the current label region is re-evaluated through comparison of magnification with the adjacent unit pattern. If the size of the neighboring label region located at the upper, lower, left, and right sides is 4 times or 1/4 times larger than the size of the current label region like the reference light pattern, the current label region is classified as a reliable "effective label". If the current label area (i, j) is empty as shown in Fig. 13, it is confirmed whether three or more adjacent label areas are " valid labels ", and a new label area (i, j) is generated through interpolation. In Fig. 11, the points 90 indicate the existing " effective label " area and the newly interpolated label area location. In FIG. 11, reference numeral 90 is assigned to several points. In FIG. 11, all the points indicated by the reference numeral 90 are given reference numeral 90.

))를 기준으로 현재 보간 수행된 레이블 영역에서의 X축 상의 "유효 레이블" 개수(즉, 유사한 Y좌표를 갖는 k번째 군집에서의 ‘유효 레이블’ 개수 (

))와 비교한다. 비교 결과, 임계치(α)이상이면 Y축에 수직으로 해당 X축 기준의 가상 라인을 생성한다(하기의 수학식 1 참조). Thereafter, the image processing unit 580 compares the number of regions on the X-axis of the reference light pattern with the number of trust regions on the X-axis belonging to the currently processed Y-axis direction clusters. If the number of the trust regions in the current cluster is more than a predetermined number, the image processing unit 580 generates a virtual horizontal line of the cluster on the virtual watermark table (S90). In other words, the total number of unit patterns having the same Y coordinate of the reference light pattern (i.e., the total number of unit patterns on the X-axis

(I.e., the number of " effective labels " in the k-th cluster having similar Y-coordinates)

)). As a result of comparison, if the difference is equal to or larger than the threshold value?, A virtual line based on the X axis is generated perpendicular to the Y axis (see Equation 1 below).

Axis is repeatedly performed for all the clusters perpendicular to the Y-axis, and a virtual watermark is generated as shown in FIG.

이고, 도 1에서 교각 상단에서 수위까지의 높이 ph는 "ph = T_d * N"이 된다. 여기서, T_d는 패턴조상대상물(40)에 조사된 참조 광패턴에서의 각 단위패턴 간 거리를 의미한다. 그에 따라, 최종 예측 수위 WH는 교각의 원래 높이 H에서 ph를 뺀 것이 된다. 즉, 최종 예측 수위 WH는 "WH = H-ph"가 된다.Next, the image processing unit 580 calculates the final predicted water level based on the virtual water table in which the virtual horizontal line is generated (S100). For example, when the total number of horizontal lines of the reference light pattern is M, the sum N of the generated virtual horizontal lines is

1, the height ph from the upper end of the pier to the water level becomes " ph = T _d * N ". Where, T _d denotes the distance between each of the unit patterns in the irradiated reference light pattern to the pattern ancestor object 40. Accordingly, the final predicted level WH is obtained by subtracting ph from the original height H of the bridge pier. That is, the final predicted level WH becomes " WH = H-ph ".

Next, the image processing unit 580 measures a distance D between the pattern irradiation object 40 and the image acquisition device 20. [ 14, the focal length of the camera is f, the distance between the unit patterns in the reference pattern light irradiated to the pattern irradiation object 40 is _Td , the distance between the unit patterns in the image frame input to the image acquisition device 20 Is d, D can be obtained through the following equation (2).

When illuminating the reference light pattern, T _d should be measured in the field to meet the minimum pixel distance criterion of d. At this time, the f value is fixed and can be confirmed by numerical values. Finally, by calculating the value of d through image processing, D can be obtained.

As described above, an optimal embodiment has been disclosed in the drawings and specification. Although specific terms have been employed herein, they are used for purposes of illustration only and are not intended to limit the scope of the invention as defined in the claims or the claims. Therefore, those skilled in the art will appreciate that various modifications and equivalent embodiments are possible without departing from the scope of the present invention. Accordingly, the true scope of the present invention should be determined by the technical idea of the appended claims.

10: light pattern irradiating device 20: image acquiring device
30: reference light pattern 40: pattern irradiated object
50: Level analysis section 60: Enclosure
70: Integrated Control Center 80: Network
510: light pattern output unit 520: light pattern generating unit
530: User Interface Unit 540: Database
550: Transmitting unit 560: Timer
570: Image input unit 580: Image processing unit

Claims (17)

A light pattern irradiating unit for irradiating a pattern irradiation object with a reference light pattern;
An image acquiring unit acquiring an image including a reference light pattern irradiated to the pattern irradiated object; And
And a water level analyzing unit for analyzing the image acquired through the image acquiring unit and measuring the current water level,
The level-
A light pattern output unit for providing a reference light pattern to be irradiated to the light pattern irradiating unit;
A user interface unit for receiving an area of interest and a pattern type;
A light pattern generator for generating a reference light pattern to be irradiated on the basis of the shape of a plurality of reference light patterns previously stored and finely adjusting the pattern shape to coincide with the pattern irradiation object, ;
An image input unit for receiving the image acquired by the image acquisition unit; And
And an image processor for performing an image process on the ROI in the input image and measuring the current water level based on the processed ROI,
The image processing unit binarizes an image in the ROI, performs pattern edge detection on the binarized image, performs labeling of the unit pattern of the reference light pattern, and labels the reference pattern on the X- and Y- Performing an interpolation on an error region by comparing each of the clustered regions, generating a virtual watermark table including virtual horizontal lines based on the interpolated result, And estimates the current water level based on the measured water level. delete delete delete delete The method according to claim 1,
Wherein the level analyzer further includes a transmitter for outputting the current level measured by the image processor to the outside. The method according to claim 1,
Wherein the reference light pattern is shaped differently according to the external shape, width, height, and distance of the pattern irradiated object. The method according to claim 1,
Wherein the reference light pattern includes a plurality of unit patterns,
And the center distances between the unit patterns have a constant interval. The method according to claim 1,
Wherein the light pattern irradiating unit includes a laser projector or an optical sensor. The light pattern irradiating unit irradiating the pattern irradiating object with a reference light pattern;
An image acquiring unit acquiring an image including a reference light pattern irradiated to the pattern irradiated object;
Generating a reference light pattern to be inspected based on a shape of a plurality of stored reference light patterns and providing the reference light pattern to the light pattern inspection unit;
And a water level analyzing step of performing image processing on a region of interest set through the user interface unit in the image and measuring a current water level based on the image area,
Wherein the step of measuring the current water level comprises:
Binarizing an image within the region of interest;
Performing pattern edge detection on the binarized image to perform labeling of the unit pattern of the reference light pattern;
Clustering and labeling the label regions having similar coordinates for the X axis and the Y axis;
Comparing each of the clustered regions and interpolating an error region;
Generating a virtual watermark table including virtual horizontal lines based on the interpolated result; And
And estimating the current water level based on the virtual water table. delete delete delete The method of claim 10,
Generating the reference light pattern to be inspected and providing the reference light pattern to the light pattern inspection unit,
Wherein the pattern type selected by the user interface unit is finely adjusted so as to coincide with the pattern irradiated object, and then provided to the light pattern irradiating unit. The method of claim 10,
Wherein the measuring the current water level further comprises outputting the measured water level to the outside. The method of claim 10,
Wherein the reference light pattern is shaped differently depending on the external shape, width, height, and distance of the pattern irradiated object. The method of claim 10,
Wherein the reference light pattern includes a plurality of unit patterns,
Wherein the center distances between the unit patterns have a constant interval.

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