A water level identification method and monitoring method, a water level identification system and a monitoring system

Abstract

This invention relates to the field of water level measurement, specifically a water level identification method, comprising: acquiring a target point in an image; determining the percentage of a first number of pixels below the target point in the vertical direction relative to a second number of pixels in the vertical direction of the image; determining a first angle between the image acquisition device and the target point based on the percentage of pixels; determining a first distance in the horizontal direction between the image acquisition device and the target point based on the target surface width of the image acquisition device and the image width or image height; and determining the water level of the target point based on the first distance and the first angle. This invention solves the technical problems of existing computer vision-based water level monitoring relying on auxiliary equipment and having a high monitoring error rate. It eliminates the need for additional equipment and effectively balances the computational load and accuracy in the image recognition process.

Description

Technical Field

[0001] This invention relates to the field of water level measurement, specifically to a water level identification method and monitoring method, a water level identification system and a monitoring system. Background Technology

[0002] Existing water level monitoring products using computer vision typically require auxiliary physical equipment, such as water level gauges and buoys. These devices, placed in the water, are prone to aging, damage, submersion, or drifting away due to complex water conditions and environmental influences. Furthermore, machine vision-based recognition of water level gauges and buoys is susceptible to weather conditions, particularly lighting, which can lead to inaccurate or non-functional readings. While methods using sonar or sensors for accurate water level monitoring are generally expensive, they add unnecessary costs to the system. Summary of the Invention

[0003] To address the technical problems of reliance on auxiliary equipment and high monitoring error rate in computer vision-based water level monitoring, this invention proposes a water level identification method and monitoring method, as well as a water level identification system and monitoring system.

[0004] A first aspect of the present invention provides a water level identification method, comprising:

[0005] Obtain the target points of the image;

[0006] Determine the percentage of the number of pixels below the position of the target point in the vertical direction of the image, relative to the total number of pixels in the vertical direction of the image;

[0007] The first angle between the image acquisition device and the target point is determined based on the percentage of the number of pixels.

[0008] The first horizontal distance between the image acquisition device and the target point is determined based on the target width of the image acquisition device and the image width or image height; the ratio of the target width to the first distance is equal to the ratio of the pixel width to the imaging width; or, the ratio of the target width to the first distance is equal to the ratio of the pixel height to the imaging height.

[0009] The water level at the target point is determined based on the first distance and the first included angle.

[0010] In one embodiment, the water level identification method further includes setting a reference point during the configuration of the image acquisition device and obtaining the reference point water level height; the reference point water level height is used to determine the height of the image acquisition device and obtain parameters of the image acquisition device; the parameters include the width of the pixel and / or the height of the pixel.

[0011] In one embodiment, determining the water level of the target point based on the first distance and the first included angle includes: calculating the ratio of the first distance to the tangent of the second included angle, which is used as the second distance between the image acquisition device and the target point in the vertical direction, wherein the second included angle is the sum of the first included angle and the installation angle of the image acquisition device.

[0012] In one embodiment, the water level at the target point is the difference between the height of the image acquisition device and the second distance.

[0013] In one embodiment, determining the first angle between the image acquisition device and the target point based on the percentage of the number of pixels includes: using the product of the percentage of the number of pixels and the vertical angle of the image acquisition device as the first angle.

[0014] A third aspect of the present invention provides a water level identification system, comprising:

[0015] Image acquisition device;

[0016] An angle calculation unit is configured to determine the percentage of a first number of pixels below the position of the target point in the image in the vertical direction, relative to the total number of pixels in the image in the vertical direction.

[0017] And, based on the percentage of the number of pixels, determine the first angle between the image acquisition device and the target point;

[0018] The distance calculation unit determines a first distance between the image acquisition device and the target point based on the target width and the image width or image height of the image acquisition device; the ratio of the target width to the first distance is equal to the ratio of the pixel width to the imaging width; or, the ratio of the target width to the first distance is equal to the ratio of the pixel height to the imaging height.

[0019] The water level calculation unit is configured to determine the water level of the target point based on a first distance and a first angle.

[0020] In some embodiments, the water level identification system further includes setting a reference point during the configuration of the image acquisition device and obtaining the reference point water level height; the reference point water level height is used to determine the height of the image acquisition device and obtain parameters of the image acquisition device; the parameters include the width of the pixel and / or the height of the pixel.

[0021] In some embodiments, determining the first angle between the image acquisition device and the target point based on the percentage of the number of pixels includes: multiplying the percentage of the number of pixels by the vertical angle of the image acquisition device as the first angle; calculating the ratio of the first distance to the tangent of the second angle as the second distance between the image acquisition device and the target point in the vertical direction, wherein the second angle is the sum of the first angle and the installation angle of the image acquisition device;

[0022] The method for determining the first distance between the image acquisition device and the target point based on the target width and the image width is as follows: calculating the magnification based on the imaging width and the pixel width, or calculating the magnification based on the imaging width and the pixel width; the first distance is the product of the target width of the image acquisition device and the magnification.

[0023] A fourth aspect of the present invention provides a water level monitoring system, based on any of the water level identification systems described above, further comprising: an early warning unit configured to issue an early warning if the water level is higher than a threshold.

[0024] This invention identifies water level conditions based on the angle and distance relationship between the target point and the image acquisition device, eliminating the need for additional auxiliary equipment and avoiding the impact of equipment damage or loss. The invention determines the angle based on the pixel ratio above and below the target point and establishes the relationship between the target surface imaging within the image acquisition device and the image itself, improving the accuracy of water level identification. It effectively balances the computational load and accuracy in the image recognition process, further enabling real-time and rapid early warning for the rapid identification and sensitive response to water level anomalies. Attached Figure Description

[0025] One or more embodiments are illustrated by way of example with reference numerals in the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements with the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0026] Figure 1 This is a flowchart of the water level identification method provided in Embodiment 1 of the present invention;

[0027] Figure 2 This is a flowchart of the water level monitoring method provided in Embodiment 2 of the present invention;

[0028] Figure 3 This is a block diagram of the water level identification system provided in Embodiment 3 of the present invention;

[0029] Figure 4 This is a block diagram of the water level monitoring system provided in Embodiment 4 of the present invention. Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the various embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, those skilled in the art will understand that many technical details are presented in the various embodiments of the present invention to facilitate a better understanding of this application. However, the technical solutions claimed in this application can be implemented even without these technical details and various changes and modifications based on the following embodiments. The division of the various embodiments below is for ease of description and should not constitute any limitation on the specific implementation of the present invention. The various embodiments can be combined with and referenced by each other without contradiction.

[0031] The first embodiment of the present invention provides a water level identification method; please refer to [link to relevant documentation]. Figure 1 .

[0032] Deploying a device that provides a water level identification method includes fixing an image acquisition device at a high position along the edge of the water flow. When the object of water level identification is a river, the image acquisition device is deployed at a high position on the side of the river, at a height that allows for a clear view of the water surface and covers a range of elevations where the water surface fluctuates. In some embodiments, the image acquisition device is a camera, such as a 2-megapixel camera, an 8-megapixel camera, etc.

[0033] Record the deployment location of the image acquisition device and use it as part of the preset data for water level identification. The preset data for water level identification includes at least: the installation height of the image acquisition device, the focal length of the image acquisition device, the installation angle γ of the image acquisition device, the number of pixels of the image acquisition device, and the chip information of the image acquisition device. If the recorded installation height of the image acquisition device is the height difference between the device and the current water level, the current water level should also be recorded for subsequent water level identification calculations.

[0034] Images are captured using a pre-deployed image acquisition device. Based on image recognition, the intersection of the water flow and the edge on the horizontal central axis of the captured image is determined as the target point. When the object being identified as a river, the target point is the intersection of the river water and the riverbank on the horizontal central axis of the image.

[0035] S1 calculates the elevation angle of the water level.

[0036] Based on the focal length of the image acquisition device in the preset data, the upper and lower angles α are found according to the focal length of the image acquisition device and the chip of the image acquisition device. A table showing the correspondence between the focal length of common image acquisition devices, the chip of the image acquisition device, and the angle is shown in Table 1.

[0037] Table 1. Correspondence between focal length, chip, and angle of image acquisition device

[0038] The height ratio angle β is calculated based on the vertical angle α. The height ratio angle β is calculated as a percentage of the number of pixels in the image segmented from the target point. Specifically, the number of first pixels below the target point's position in the image in the vertical direction is obtained, the total number of pixels in the image in the vertical direction is obtained, and the percentage p of the number of first pixels below the target point's position in the image in the vertical direction is calculated relative to the total number of pixels in the image in the vertical direction.

[0039] In some embodiments, the height ratio angle β is calculated as follows: β = p × α. Where β is the height ratio angle, p is the percentage of the number of pixels below the target point in the vertical direction relative to the total number of pixels in the vertical direction of the image, and α is the vertical angle.

[0040] The elevation angle θ of the water level is calculated based on the elevation ratio angle β. In some embodiments, the elevation angle θ of the water level is calculated as follows: Elevation angle θ of water level = Elevation ratio angle β + Installation angle γ of the image acquisition device. Wherein, θ is the elevation angle of the water level, β is the elevation ratio angle, and γ is the installation angle of the image acquisition device.

[0041] In some embodiments, a water level point during the configuration process of the image acquisition device is used as a reference point to capture an image and determine the water level height at the reference point. Based on the water level height at the reference point, parameters in the image acquisition device, such as pixel width and pixel height, are determined. The pixel width is calculated as the product of the image resolution and the image width; the pixel height is calculated as the product of the image resolution and the image height.

[0042] S2 calculates the first horizontal distance from the image acquisition device to the target point.

[0043] A first distance between the image acquisition device and the target point is determined based on the target width of the image acquisition device and the image width or image height. The ratio of the target width to the first distance is equal to the ratio of the pixel width to the imaging width; or, the ratio of the target width to the first distance is equal to the ratio of the pixel height to the imaging height.

[0044] S3 calculates the water level at the target point.

[0045] In some embodiments, the ratio of the first distance to the tangent of the elevation angle θ is calculated as the second distance in the vertical direction between the image acquisition device and the target point. The water level at the target point is the difference between the height of the image acquisition device and the second distance. That is, the second distance M in the vertical direction between the image acquisition device and the target point is calculated as: M = L / tanθ. Where M is the second distance in the vertical direction between the image acquisition device and the target point, L is the first distance in the horizontal direction between the image acquisition device and the target point, and θ is the elevation angle of the water level. In some embodiments, if the installation height of the image acquisition device acquired when deploying preset data is the height difference from the current horizontal plane as the installation height of the image acquisition device, then the water level H is calculated as: H = Y + XM. Where H is the water level, Y is the height difference of the current horizontal plane of the image acquisition device at installation, X is the water level of the reference point at installation, and M is the second distance in the vertical direction between the image acquisition device and the target point.

[0046] A second embodiment of the present invention provides a water level monitoring method based on the water level identification method provided in the first embodiment. When deploying preset data, an upper limit threshold, a lower limit threshold, and an early warning method are set for water level warnings. The upper and lower limit thresholds determined by the water level identification method provided in the first embodiment are compared; if the water level is higher than the upper limit threshold or lower than the lower limit threshold, an early warning is issued. Early warning methods include, but are not limited to, system warnings, SMS warnings, and telephone notification warnings.

[0047] In some embodiments, the frequency of horizontal monitoring and the frequency of image acquisition by the image acquisition device for water level identification and monitoring are adjusted based on weather and environmental conditions. In some embodiments, the water level is identified and monitored once every hour by default. In severe weather conditions, it can be set to identify and monitor the water level once every 30 seconds to promptly identify abnormal water level conditions and take effective measures.

[0048] The third embodiment of the present invention provides a water level identification system; please refer to [link / reference]. Figure 3 It includes an image acquisition device, an angle calculation unit, a distance calculation unit, and a water level calculation unit.

[0049] The image acquisition device is configured to acquire images for water level identification after deployment.

[0050] The image acquisition device is fixed at a high position along the edge of the water flow. When the object being identified is a river, the image acquisition device is deployed at a high position on the side of the river, at a height that allows for a clear view of the water surface and covers the range of water surface fluctuations. In some embodiments, the image acquisition device is a camera, such as a 2-megapixel camera or an 8-megapixel camera.

[0051] Record the deployment location of the image acquisition device and use it as part of the preset data for water level identification. The preset data for water level identification includes at least: the installation height of the image acquisition device, the focal length of the image acquisition device, the installation angle γ of the image acquisition device, the number of pixels of the image acquisition device, and the chip information of the image acquisition device. If the recorded installation height of the image acquisition device is the height difference between the device and the current water level, the current water level should also be recorded for subsequent water level identification calculations.

[0052] In some embodiments, a water level point during the configuration process of the image acquisition device is used as a reference point to capture an image and determine the water level height at the reference point. Based on the water level height at the reference point, parameters in the image acquisition device, such as pixel width and pixel height, are determined. The pixel width is calculated as the product of the image resolution and the image width; the pixel height is calculated as the product of the image resolution and the image height.

[0053] Images are captured using a pre-deployed image acquisition device. Based on image recognition, the intersection of the water flow and the edge on the horizontal central axis of the captured image is determined as the target point. When the object being identified as a river, the target point is the intersection of the river water and the riverbank on the horizontal central axis of the image.

[0054] The angle calculation unit is configured to calculate the elevation angle of the water level.

[0055] Based on the focal length of the image acquisition device in the preset data, the upper and lower angles α are found according to the focal length of the image acquisition device and the chip of the image acquisition device. A table showing the correspondence between the focal length of common image acquisition devices, the chip of the image acquisition device, and the angle is shown in Table 1.

[0056] Table 2. Correspondence between focal length, chip, and angle of image acquisition device

[0057]

[0058]

[0059] The height ratio angle β is calculated based on the vertical angle α. The height ratio angle β is calculated as a percentage of the number of pixels in the image segmented from the target point. Specifically, the number of first pixels below the target point's position in the image in the vertical direction is obtained, the total number of pixels in the image in the vertical direction is obtained, and the percentage p of the number of first pixels below the target point's position in the image in the vertical direction is calculated relative to the total number of pixels in the image in the vertical direction.

[0060] In some embodiments, the height ratio angle β is calculated as follows: β = p × α. Where β is the height ratio angle, p is the percentage of the number of pixels below the target point in the vertical direction relative to the total number of pixels in the vertical direction of the image, and α is the vertical angle.

[0061] The elevation angle θ of the water level is calculated based on the elevation ratio angle β. In some embodiments, the elevation angle θ of the water level is calculated as follows: Elevation angle θ of water level = Elevation ratio angle β + Installation angle γ of the image acquisition device. Wherein, θ is the elevation angle of the water level, β is the elevation ratio angle, and γ is the installation angle of the image acquisition device.

[0062] The distance calculation unit is configured to calculate a first distance in the horizontal direction from the image acquisition device to the target point.

[0063] A first distance between the image acquisition device and the target point is determined based on the target width of the image acquisition device and the image width or image height. The ratio of the target width to the first distance is equal to the ratio of the pixel width to the imaging width; or, the ratio of the target width to the first distance is equal to the ratio of the pixel height to the imaging height.

[0064] The water level calculation unit is configured to calculate the water level at the target point.

[0065] In some embodiments, the ratio of the first distance to the tangent of the elevation angle θ is calculated as the second distance in the vertical direction between the image acquisition device and the target point. The water level at the target point is the difference between the height of the image acquisition device and the second distance. That is, the second distance M in the vertical direction between the image acquisition device and the target point is calculated as: M = L / tanθ. Where M is the second distance in the vertical direction between the image acquisition device and the target point, L is the first distance in the horizontal direction between the image acquisition device and the target point, and θ is the elevation angle of the water level. In some embodiments, if the installation height of the image acquisition device acquired when deploying preset data is the height difference from the current horizontal plane as the installation height of the image acquisition device, then the water level H is calculated as: H = Y + XM. Where H is the water level, Y is the height difference of the current horizontal plane of the image acquisition device at installation, X is the water level of the reference point at installation, and M is the second distance in the vertical direction between the image acquisition device and the target point.

[0066] The fourth embodiment of the present invention provides a water level monitoring system, which is based on the water level identification system provided in the third embodiment, and further includes an early warning unit, which is configured to issue an early warning if the water level is higher than a threshold.

[0067] When deploying pre-set data, upper and lower threshold values ​​for water level warnings and warning methods are set. The upper and lower threshold values ​​are compared with those determined by the water level identification method provided in the first embodiment. If the water level is higher than the upper threshold or lower than the lower threshold, a warning is issued. Warning methods include, but are not limited to, system warnings, SMS warnings, and telephone notification warnings.

[0068] In some embodiments, the frequency of horizontal monitoring and the frequency of image acquisition by the image acquisition device for water level identification and monitoring are adjusted based on weather and environmental conditions. In some embodiments, the water level is identified and monitored once every hour by default. In severe weather conditions, it can be set to identify and monitor the water level once every 30 seconds to promptly identify abnormal water level conditions and take effective measures.

[0069] The above embodiments identify water level conditions based on the angle and distance relationship between the image acquisition device and the target point reflecting the water level, eliminating the need for additional auxiliary equipment and avoiding the impact of equipment damage or loss. These embodiments determine the angle based on the pixel ratio above and below the target point and establish the relationship between the target surface imaging within the image acquisition device and the image itself, improving the accuracy of water level identification. This effectively balances the computational load and accuracy in the image recognition process, further enabling real-time and rapid early warning for the rapid identification and sensitive response to water level anomalies.

[0070] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The program can be stored in a computer-readable storage medium, and when the program is executed, it can include the processes of the embodiments of the methods described above.

[0071] Those skilled in the art will understand that the above embodiments are specific examples of implementing the present invention, and in practical applications, various changes in form and detail may be made without departing from the spirit and scope of the present invention.

Claims

1. A water level recognition method characterized by, The method comprises: acquiring a target point of an image, the target point being a cross point of a water flow and an edge on a horizontal central axis of the image; determining a first number of pixels below a vertical direction of a position of the target point in the image, the first number of pixels accounting for a percentage of a total number of pixels in the vertical direction of the image; determining a first angle between the image acquisition device and the target point based on the percentage of the number of pixels, wherein the first angle is calculated based on a product of an up-down angle and the percentage; determining a first distance between the image acquisition device and the target point in a horizontal direction based on a target surface width of the image acquisition device and an image width or an image height, wherein a ratio of the target surface width to the first distance is equal to a ratio of a width of the pixel to an imaging width, or a ratio of the target surface width to the first distance is equal to a ratio of a height of the pixel to an imaging height; calculating a second distance between the image acquisition device and the target point in the vertical direction based on a ratio of the first distance to a tangent value of the first angle, and calculating a water level of the target point based on a difference between a height difference of a current horizontal plane when the image acquisition device is installed and a reference point water level height and the second distance.

2. The water level recognition method according to claim 1, characterized by, The water level recognition method further comprises setting a reference point during configuration of the image acquisition device and acquiring a reference point water level height of the reference point, wherein the reference point water level height is used to determine a height of the image acquisition device and obtain parameters of the image acquisition device, and the parameters include a width of the pixel and / or a height of the pixel.

3. The water level recognition method according to claim 1, characterized by, The water level recognition method based on the first distance and the first angle comprises: calculating a ratio of the first distance to a tangent value of a second angle as a second distance between the image acquisition device and the target point in the vertical direction, and the second angle is a sum of the first angle and an installation angle of the image acquisition device.

4. A water level monitoring method characterized by, The water level recognition method based on any one of claims 1-3 comprises: issuing a warning if the water level is higher than a threshold value.

5. A water level recognition system characterized by, The method comprises: an image acquisition device; an angle calculation unit configured to determine a first number of pixels below a vertical direction of a position of a target point in an image, the target point being a cross point of a water flow and an edge on a horizontal central axis of the image, the first number of pixels accounting for a percentage of a total number of pixels in the vertical direction of the image; and determine a first angle between the image acquisition device and the target point based on the percentage of the number of pixels, wherein the first angle is calculated based on a product of an up-down angle and the percentage; a distance calculation unit configured to determine a first distance between the image acquisition device and the target point in a horizontal direction based on a target surface width of the image acquisition device and an image width or an image height, wherein a ratio of the target surface width to the first distance is equal to a ratio of a width of the pixel to an imaging width, or a ratio of the target surface width to the first distance is equal to a ratio of a height of the pixel to an imaging height. The water level calculation unit is configured to calculate a second distance between the image acquisition device and the target point in a vertical direction based on a ratio of the first distance to the tangent value of the first included angle, and calculate the water level of the target point based on a difference between a height difference of a current horizontal plane when the image acquisition device is installed and a reference point water level height and the second distance.

6. The water level recognition system according to claim 5, characterized in that The water level recognition system further comprises setting a reference point during configuration of the image acquisition device, and obtaining a reference point water level height of the reference point; the reference point water level height is used to determine the height of the image acquisition device, and obtain parameters of the image acquisition device; the parameters include the width of the pixel, and / or the height of the pixel.

7. The water level recognition system of claim 5, wherein The method for determining the first included angle between the image acquisition device and the target point based on the percentage of the pixel number comprises: taking a product of the percentage of the pixel number and an up-down angle of the image acquisition device as the first included angle; calculating a ratio of the first distance to a tangent value of a second included angle as a second distance between the image acquisition device and the target point in a vertical direction, the second included angle being a sum of the first included angle and an installation angle of the image acquisition device. The method for determining the first distance between the image acquisition device and the target point based on the target surface width and the image width comprises: calculating a magnification based on the imaging width and the width of the pixel, or calculating a magnification based on the imaging width and the width of the pixel; the first distance being a product of the target surface width of the image acquisition device and the magnification.

8. A water level monitoring system characterized by, The water level recognition system based on any one of claims 5-7 further comprises a warning unit configured to issue a warning if the water level is higher than a threshold.

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