A method and device for correcting preset positions of monitoring cameras in a substation

Abstract

The present invention relates to a method and device for pre-position correction of a substation monitoring camera. The method obtains an initial panoramic image, obtains initial pre-position reference parameter data of all devices from the initial panoramic image, and extracts the initial pre-position reference parameter data of one device as the first initial pre-position reference parameter data; obtains a panoramic image to be detected, and reversely infers the pre-position parameter data to be detected of the remaining devices in the panoramic image to be detected according to the first initial pre-position reference parameter data; compares the initial pre-position reference parameter data with the pre-position parameter data to be detected, and determines the type of pre-position offset; performs pre-position correction according to the type of pre-position offset. Compared with the prior art, the present invention has the advantages of effectively improving the pertinence and accuracy of the pre-position correction method.

Description

Technical Field

[0001] The present invention relates to the technical field of substation remote viewing systems, and in particular to a method and device for correcting preset positions of substation monitoring cameras. Background Art

[0002] With the continuous development of the power industry, the continuous expansion of the scale of the power network, the increasingly updated equipment, and the basic formation of the power communication network, the information application of my country's power industry has been continuously deepened many years ago. At present, most substations use "five remote" (telemetry, telecommunication, remote control, remote adjustment, and remote viewing) monitoring, which basically realizes the unmanned operation with few people, greatly improving the production efficiency of my country's power industry. Directly understand and grasp the situation of each substation and communication station, so as to respond to the situation very quickly and timely.

[0003] At present, after installing, configuring and debugging the camera, the PTZ in the substation often saves the camera's shooting position at different angles, focal lengths, exposure and other parameters into the system. However, due to the inherent error of the PTZ transmission structure, the invasion of foreign objects into the PTZ transmission structure, the displacement of the PTZ fixed frame and other factors, the PTZ preset parameters in the initial state will no longer be applicable, and the PTZ preset position needs to be recalibrated and the preset position parameters updated.

[0004] However, different factors have different effects on the camera, and the correction methods are also different. The transmission error of the gimbal itself is an inherent factor, which should exist throughout the entire gimbal use cycle. In the initial state, the meshing between the gears is relatively sufficient and the error is small. As the running time goes by, the wear between the gears, the loosening of the transmission structure, etc., the error will gradually increase; foreign body intrusion is obviously different from the transmission error of the gimbal. It suddenly intervenes in the system at a certain moment, causing a large error to the system, and due to the irregularity of the foreign body and the random structural characteristics, its impact on each preset position will be different, presenting an irregular error; unlike the above two factors, the offset of the gimbal fixed frame is a fixed offset applied to the gimbal system, which is reflected as a regular error. However, the existing gimbal preset position recalibration method can often only deal with a single influencing factor, resulting in an increase in the misjudgment rate. Therefore, how to achieve more targeted preset position correction and reduce the misjudgment rate has become a problem that needs to be solved in this field. Summary of the invention

[0005] The purpose of the present invention is to overcome the defect of the above-mentioned prior art that the preset position of the camera of the substation remote viewing system lacks a more reasonable re-calibration means, and to provide a substation monitoring camera preset position correction method and device, which can diagnose the cause of the deviation of the substation camera preset position and adopt different re-calibration methods for the preset position deviation caused by different reasons.

[0006] The purpose of the present invention can be achieved by the following technical solutions:

[0007] According to a first aspect of the present invention, there is provided a method for pre-position correction of a substation monitoring camera, comprising the following steps: S1, obtaining an initial panoramic image, obtaining initial pre-position reference parameter data of all devices from the initial panoramic image, and extracting the initial pre-position reference parameter data of one of the devices as first initial pre-position reference parameter data; S2, obtaining a panoramic image to be detected, and reversely calculating the pre-position parameter data to be detected of the remaining devices in the panoramic image to be detected according to the first initial pre-position reference parameter data; S3, comparing the initial pre-position reference parameter data with the pre-position parameter data to be detected to determine the type of pre-position offset; S4, performing pre-position correction according to the type of pre-position offset.

[0008] As a preferred technical solution, the initial preset position reference parameter data includes a horizontal rotation angle, a vertical rotation angle and a focal length.

[0009] As a preferred technical solution, S1 specifically includes: S11, quantification of the initial panoramic image preset position, including determining the rotation reference of the initial panoramic image in the horizontal and vertical directions; S12, initial panoramic image feature extraction, including extracting the initial panoramic image structural features using the SURF algorithm; S13, preset position reference parameter calculation, including obtaining the inventory data of all equipment in the substation and calculating the corresponding initial preset position reference parameter data.

[0010] As a preferred technical solution, S2 further includes: extracting structural features of the panoramic image to be detected by using a SURF algorithm, and comparing them with the structural features of the initial panoramic image to remove unmatched objects.

[0011] As a preferred technical solution, the preset position offset types include gimbal fixed frame offset, gimbal transmission error offset and gimbal foreign body intrusion offset.

[0012] As an optimal technical solution, S3 specifically includes: respectively calculating the difference between the initial preset position reference parameter data of the remaining devices in the initial panoramic image and the preset position parameter data to be detected of the corresponding devices in the panoramic image to be detected; obtaining the comprehensive calculation results of the corresponding differences of all devices, and judging the type of preset position offset according to the comprehensive calculation results: if the comprehensive calculation result meets the first preset condition, it is judged as the gimbal fixed frame offset; if the comprehensive calculation result meets the second preset condition, then judging whether the difference calculation results of a single device meet the third preset condition: when the third preset condition is met, it is judged as the gimbal's own transmission error offset, otherwise it is judged as the gimbal foreign body intrusion offset.

[0013] As a preferred technical solution, the comprehensive calculation result is:

[0014]

[0015]

[0016] In the formula, , are the angle differences of the public device pair on the rows and columns of the initial panoramic image and the panoramic image to be detected, is the sum of squares of the differences in rows and columns for each device, , are the 0° scale line angle parameter values ​​of the initial panoramic image, are the row and column angle values ​​of the 0° scale line of the panoramic image to be detected, It is the sum of squares of the errors between the 0° scale line of the panoramic image to be detected and the initial panoramic image in rows and columns.

[0017] As a preferred technical solution, the first preset condition is and , the second preset condition is and ,in, and These are all pre-set thresholds.

[0018] As a preferred technical solution, the third preset condition is:

[0019]

[0020]

[0021] In the formula, , are the angle differences between the reference device pair on the rows and columns of the initial panoramic image and the panoramic image to be detected, For device pair The corresponding image angle parameter value, j ≠1, For device pair The corresponding image angle parameter value.

[0022] According to a second aspect of the present invention, a substation monitoring camera preset position correction device includes a memory, a processor, and a program stored in the memory, and the method described is implemented when the processor executes the program.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] 1. The present invention provides a pre-position correction method for a substation monitoring camera. After obtaining the initial pre-position reference parameter data of all devices from the initial panoramic image, the parameter data of one device is extracted from it as a reference, and then the pre-position parameter data to be detected of the remaining devices in the panoramic image to be detected are reversely calculated. The pre-position offset type / error type is determined according to the comparison result between the initial pre-position reference parameter data and the pre-position parameter data to be detected, and then a corresponding correction scheme is adopted according to the judgment result, which can effectively improve the pertinence and accuracy of the pre-position correction method;

[0025] 2. The method provided by the present invention can reduce the influence of factors such as light intensity, weather, dust, etc. on the grayscale of the image by adding image binarization, making the image positioning process more accurate and reducing the possibility of misjudgment. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A schematic diagram of a method flow chart provided in an embodiment of the present invention;

[0027] Figure 2 Schematic diagram of the 0° scale line of the initial panoramic image in an embodiment of the present invention;

[0028] Figure 3 is the positional relationship between the two images in the embodiment of the present invention. DETAILED DESCRIPTION

[0029] The present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. The following embodiments are implemented based on the technical solution of the present invention, and provide detailed implementation methods and specific operation processes, but the protection scope of the present invention is not limited to the following embodiments. Example

[0030] This embodiment provides a method for calibrating the preset position of a substation surveillance camera, the core purpose of which is to diagnose the cause of the deviation of the preset position of the substation camera, propose different recalibration methods for the preset position deviation caused by different reasons, and guide the recalibration of the preset position of the substation camera. The method records images at different times, compares them with the preset position images in the initial state, analyzes the offset direction and offset of the preset position images at different positions, summarizes the regularity analysis, determines the cause of the offset, and guides the recalibration of the preset position of the substation camera.

[0031] like Figure 1 As shown, the substation monitoring camera preset position correction method provided in this embodiment specifically includes the following steps:

[0032] Step S1, initial preset position reference is established.

[0033] This step first obtains an initial panoramic image, and obtains the initial preset position reference parameter data of all devices from it, extracts the initial preset position reference parameter data of one device (first initial preset position reference parameter data), and uses it as reference data for calculating the parameters of the panoramic image to be detected in subsequent steps. Specifically, it includes:

[0034] Step S11, quantizing the initial panoramic image preset position, taking a specific camera as the object, acquiring its panoramic image, and determining the 0° scale lines in the horizontal and vertical directions, so that the camera has a rotation reference for reference;

[0035] Step S12, initial panoramic image feature extraction, extracting structural features in the image based on the SURF (Speed ​​Up Robust Features) algorithm to avoid positioning interference caused by factors such as weather and lighting;

[0036] Step S13, preset position reference parameter calculation, combining the substation equipment ledger data, calculate the initial preset position reference parameter data of the equipment within the field of view, the data includes: horizontal rotation angle, vertical rotation angle, focal length, this data is used as the reference control group.

[0037] Step S2: locating the target to be detected in the panoramic image.

[0038] This step first determines the panoramic image to be detected and performs the following steps:

[0039] Step S21, extracting features of the panoramic image to be detected, such as extracting structural features in the panoramic image to be detected using a SURF algorithm, and comparing the features extracted from the initial preset position image to remove mismatched objects;

[0040] Step S22, quantifying the preset position of the panoramic image to be detected, taking a certain device determined in step S1 as a reference, substituting the initial preset position reference parameter data of the device into the panoramic image to be detected, and reversely calculating the preset position parameter data of the remaining devices to be detected, thereby avoiding the error caused by resetting the reference 0° scale line.

[0041] Step S3, determining the preset position offset type.

[0042] Before determining the preset position offset type, the principles of several offset types / error types are first introduced:

[0043] (1) Gimbal’s own transmission error offset

[0044] The gimbal achieves horizontal and vertical rotation through motors, gears, belts and other mechanical structures. When the gears are engaged, a certain gap will be generated. This gap will cause a return difference and then cause a preset position deviation. The preset position deviation of this type of camera often starts out very small. As time goes by, the gears, belts and other transmission structures wear out and gradually increase. It is a gradual, approximately linear process.

[0045] (2) PTZ fixed frame offset

[0046] The gimbal fixed structure is affected by various factors, resulting in settlement, deformation, tilt, etc. The camera gimbal fixed on it will inevitably shift accordingly. This type of deviation is a sudden large deviation at a certain moment, and then the deviation no longer changes, which shows a step process.

[0047] (3) Gimbal foreign body intrusion deviation

[0048] Foreign objects invade the transmission mechanism such as gears and belts, or the transmission mechanism rusts, causing the transmission mechanism to become stuck and not smooth, and unable to rotate smoothly to the target position. This type of deviation is manifested in that the deviation value of each preset position is not fixed, and it fluctuates, and even affects the visual range of the camera, which manifests as a superposition of noise.

[0049] After understanding the above preset position offset types, the type identification mainly includes two processes: preset position error calculation and deviation type analysis. Among them, preset position error calculation refers to:

[0050] Step S31, performing error calculation between the preset position parameters of the horizontal rotation angle and the vertical rotation angle of each device of the panoramic image to be detected and the initial reference;

[0051] Deviation type analysis refers to analyzing the preset position error type based on the calculated preset position error. The specific analysis process includes:

[0052] Step S32, based on the error calculation results of each device, obtain the comprehensive calculation results of the corresponding differences of all devices: if the comprehensive calculation results meet the first preset condition, it is judged as the offset of the gimbal fixed frame; if the comprehensive calculation results meet the second preset condition, then judge whether the difference calculation results of each device meet the third preset condition: when the third preset condition is met, it is judged as the gimbal's own transmission error offset, otherwise it is judged as the gimbal foreign body intrusion offset.

[0053] Step S4: preset position calibration.

[0054] This step gives the corresponding correction method based on the analysis results in step S32. For errors caused by foreign body intrusion, the camera needs to be disassembled, cleaned, and maintained, and the initial preset position needs to be updated; for the offset error of the gimbal structure, the equipment within its field of view needs to be re-evaluated. If it does not affect the observation equipment, the initial preset position is directly updated, otherwise the camera needs to be reinstalled and adjusted; for the transmission error of the gimbal itself, the initial preset position can be directly updated.

[0055] A specific implementation process of steps S1 to S4 is as follows:

[0056] In order to reasonably set the preset position of the camera, it is first necessary to scale the initial panoramic image, determine the horizontal and vertical 0° scale lines of the image, and record the pixel row and column values ​​where the scale lines are located. ,like Figure 2 As shown. Based on SURF, the structural feature information in the panoramic image is extracted, and according to the substation equipment ledger and equipment field of view and other data information, the clear imaging equipment in the panoramic image is classified and sorted, and the horizontal angle, vertical angle and focal length of each device are recorded. SURF has the advantages of scale invariance, even if the rotation angle, brightness or shooting angle of the image is changed, it can reduce the impact of factors such as weather and lighting on positioning.

[0057] Similarly, the structural features of the panoramic image to be detected are extracted. Here, the focal length of the panoramic image to be detected must be consistent with the focal length of the image in the initial state, otherwise the correction conditions are not met. The preset position parameters of each device are recorded based on the equipment ledger. For the panoramic image to be detected, in order to avoid errors caused by inconsistent division of the 0° scale line, this embodiment takes one of the devices as the object, extracts the parameter value of the device in the initial panoramic image, and reversely calculates the parameter values ​​of each device. The principle is as follows:

[0058] Taking device 1 and device 2 as an example, the parameter value of device 1 in the initial panoramic image is , the pixel values ​​of devices 1 and 2 in the panoramic image to be detected are , is the angle value represented by each unit pixel. Let the parameter value of device 1 be is the reference in the panoramic image to be detected, so the parameter value of device 2 The calculation method is as follows:

[0059] (1)

[0060] (2)

[0061] Similarly, the row and column values ​​of the 0° scale line of the panoramic image to be detected are reversed as shown below.

[0062] (3)

[0063] (4)

[0064] In the formula, are respectively the row and column angle values ​​of the 0° scale line of the panoramic image to be detected.

[0065] like Figure 3 As shown in the figure, the initial panoramic image when the camera is installed and the panoramic image to be detected after running for a period of time are respectively. The common device pairs of the initial panoramic image and the panoramic image to be detected are respectively recorded as ,in, , The device pairs , The corresponding image angle parameter value. The representative device is used as the benchmark, and the difference between the parameter values ​​of the remaining devices in the initial panoramic image and the panoramic image to be detected is calculated as follows:

[0066] (5)

[0067] (6)

[0068] (7)

[0069] In the formula, , are the angle differences of the public device pair on the rows and columns of the initial panoramic image and the panoramic image to be detected, , The device pairs , The corresponding image angle parameter value.

[0070] The reason for the deviation between the two images is analyzed based on the parameter value difference between each common device pair, as follows:

[0071] (8)

[0072] (9)

[0073] In the formula, The sum of squares of the differences in rows and columns for each device reflects the cumulative error of the two images. , are the 0° scale line angle parameter values ​​of the initial panoramic image, It is the sum of squares of the errors between the 0° scale line of the panoramic image to be detected and the initial panoramic image in rows and columns.

[0074] According to formula (8)~(9), we can get the comprehensive calculation results and judge:

[0075] like and , it can be considered that the camera PTZ preset position deviation is small and can be ignored;

[0076] like and , it is considered that the PTZ fixed structure is offset, resulting in the offset of the 0° scale line. It is necessary to determine whether the camera needs to be adjusted based on the impact on the observation equipment. If the camera is adjusted, the initial preset position reference value needs to be reset;

[0077] like and , we need to further analyze the causes of the changes. For the pre-set threshold:

[0078] like Respectively meet:

[0079] (10)

[0080] (11)

[0081] This indicates that the preset position deviation is the transmission error offset of the PTZ itself, that is, due to the transmission error of the device itself, the gear and belt transmission process are not fully engaged, and the error caused will be linearly accumulated to the offset. During the life cycle of the device, you only need to re-update the preset position parameters with the current parameter values.

[0082] If the relationship reflected by equations (10) to (11) is not satisfied, there is an irregular relationship between the preset position error and the rotation angle, and it is determined that there is foreign matter intruding into the camera pan / tilt. The camera needs to be disassembled, repaired, and reinstalled to set the preset position.

[0083] Furthermore, this embodiment also provides a substation monitoring camera preset position correction device, including a memory, a processor, and a program stored in the memory. When the processor executes the program, the various steps of the aforementioned method are implemented, and the specific process will not be repeated.

[0084] In summary, in order to solve the problem of lack of re-calibration means for the preset position of the camera in the substation remote viewing system, the present invention compares the difference between the current remote viewing system camera image and the image in the initial state, analyzes the causes of the difference between the two, and proposes different solutions accordingly, thereby providing a new reference basis for the re-calibration of the substation remote viewing system.

[0085] The preferred specific embodiments of the present invention are described in detail above. It should be understood that a person skilled in the art can make many modifications and changes based on the concept of the present invention without creative work. Therefore, any technical solution that can be obtained by a person skilled in the art through logical analysis, reasoning or limited experiments based on the concept of the present invention on the basis of the prior art should be within the scope of protection determined by the claims.

Claims

1. A method for calibrating a preset position of a substation monitoring camera, characterized in that: The following steps are involved: S1, obtaining an initial panoramic image, obtaining initial preset position reference parameter data of all devices from the initial panoramic image, and extracting the initial preset position reference parameter data of one of the devices as first initial preset position reference parameter data; S2, acquiring the panoramic image to be detected, and reversely calculating the preset position parameter data to be detected of the remaining devices in the panoramic image to be detected according to the first initial preset position reference parameter data; S3, comparing the initial preset position reference parameter data with the preset position parameter data to be detected, and determining the preset position offset type; S4, performing preset position correction according to the preset position offset type; The preset position offset types include gimbal fixed frame offset, gimbal transmission error offset and gimbal foreign body intrusion offset; The S3 specifically includes: respectively calculating the differences between the initial preset position reference parameter data of the remaining devices in the initial panoramic image and the preset position parameter data to be detected of the corresponding devices in the panoramic image to be detected; Obtain the comprehensive calculation results of the corresponding differences of all devices, and determine the preset position offset type according to the comprehensive calculation results: If the comprehensive calculation result meets the first preset condition, it is determined that the gimbal fixed frame is offset; If the comprehensive calculation result meets the second preset condition, then determine whether the difference calculation results of the individual devices meet the third preset condition: When the third preset condition is met, it is determined that the deviation is caused by the transmission error of the gimbal itself; otherwise, it is determined that the deviation is caused by the invasion of foreign matter by the gimbal; The comprehensive calculation result is: ， ， In the formula, , are the angle differences of the common device pair on the rows and columns of the initial panoramic image and the panoramic image to be detected, respectively. The common device pair is the same device existing in the initial panoramic image and the panoramic image to be detected. is the sum of squares of differences in rows and columns for each device, D and d represent the same device in the initial panoramic image and the panoramic image to be detected, M and N represent the row and column angle values ​​of the device in the initial panoramic image, respectively, j=2, 3, 4, ..., is a counting variable, indicating the sequence number of different device pairs used for calculation, , are the 0° scale line angle parameter values ​​of the initial panoramic image, are the row and column angle values ​​of the 0° scale line of the panoramic image to be detected, is the sum of squares of the errors in rows and columns between the 0° scale line of the panoramic image to be detected and the initial panoramic image; The first preset condition is and , the second preset condition is and ,in, and These are all pre-set thresholds; The third preset condition is: ， ， In the formula, , are the angle differences between the reference device pair on the rows and columns of the initial panoramic image and the panoramic image to be detected, For device pair The corresponding image angle parameter value, For device pair The corresponding image angle parameter value.

2. The method for correcting the preset position of a substation monitoring camera according to claim 1, characterized in that: The initial preset position reference parameter data includes a horizontal rotation angle, a vertical rotation angle and a focal length.

3. The method for correcting the preset position of a substation monitoring camera according to claim 1, characterized in that: The S1 specifically includes: S11, quantizing the preset position of the initial panoramic image, including determining the rotation reference of the initial panoramic image in the horizontal direction and the vertical direction; S12, extracting features of the initial panoramic image, including extracting structural features of the initial panoramic image using a SURF algorithm; S13, calculation of preset position reference parameters, including obtaining the inventory data of all equipment in the substation and calculating the corresponding initial preset position reference parameter data.

4. The method for correcting the preset position of a substation monitoring camera according to claim 3, characterized in that: The S2 further includes: extracting structural features of the panoramic image to be detected by using a SURF algorithm, and comparing the structural features with the initial panoramic image to remove unmatched objects.

5. A substation monitoring camera preset position correction device, comprising a memory, a processor, and a program stored in the memory, characterized in that: When the processor executes the program, the method according to any one of claims 1 to 4 is implemented.

Images