A method and device for correcting distortion images of overhead line insulators
By using graph theory algorithms and perspective transformation correction methods to process image distortion of overhead line insulators, the problem of analyzing the impact of image distortion acquired by monitoring terminals was solved, achieving efficient image correction and accurate analysis of icing status.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- ELECTRIC POWER RES INST CHINA SOUTHERN POWER GRID CO LTD
- Filing Date
- 2022-11-28
- Publication Date
- 2026-06-09
AI Technical Summary
The insulator images collected by the existing overhead line monitoring terminal have perspective distortion, which affects the subsequent analysis of icing status.
Insulator images are acquired through monitoring terminals, segmented using a preset graph theory algorithm, and the degree of distortion is analyzed by combining geometric symmetry. The correction process is then performed using the principle of perspective transformation to obtain a corrected insulator image.
It effectively corrects severely distorted images, reduces computational load, ensures the effectiveness of subsequent analysis, and meets engineering requirements.
Smart Images
Figure CN115797207B_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of image processing technology, and in particular to a method and apparatus for correcting image distortion of overhead line insulators. Background Technology
[0002] Overhead transmission line insulators consist of multiple disc-shaped insulators, serving as both electrical insulation and mechanical support. To monitor the transmission line status in real time, power grid companies have installed numerous online monitoring terminals for image acquisition. However, due to the shooting angle, the insulator images captured by the cameras suffer from perspective distortion, where the disc-shaped insulators appear larger in the foreground and smaller in the background. Failure to address this perspective distortion can affect the analysis of insulator icing conditions, and even directly impact the analysis results. Summary of the Invention
[0003] This application provides a method and apparatus for correcting image distortion of insulators on overhead lines, which solves the technical problem that the images of insulators collected by monitoring terminals on existing overhead lines are distorted, affecting the subsequent analysis of the icing status of insulators.
[0004] In view of this, the first aspect of this application provides a method for correcting image distortion of overhead line insulators, comprising:
[0005] Images of insulators are obtained through monitoring terminals on overhead lines;
[0006] The insulator image is segmented using a preset graph theory algorithm to obtain an insulator segmentation map;
[0007] The distortion degree of the insulator segmentation diagram is analyzed by geometric symmetry, and the distorted images to be corrected are selected.
[0008] The distortion correction process is performed on the image to be corrected based on the principle of perspective transformation to obtain the corrected insulator image.
[0009] Preferably, acquiring insulator images through a monitoring terminal on the overhead line includes:
[0010] Initial images are obtained through monitoring terminals on overhead power lines;
[0011] The initial image without insulators is removed based on the preset position of the camera of the monitoring terminal to obtain the filtered image;
[0012] Invalid images are removed from the filtered images based on the camera's shooting status to obtain insulator images.
[0013] Preferably, the step of segmenting the insulator image using a preset graph theory algorithm to obtain an insulator segmentation map includes:
[0014] Perform an insulator region bounding box annotation operation on the insulator image to obtain the insulator bounding box;
[0015] Based on the insulator annotation box and the preset Gaussian mixture model, foreground analysis is performed on the insulator image to obtain the proposed foreground and background of the insulator.
[0016] Based on the preset source node, preset sink node, the proposed foreground of the insulator, and the proposed background of the insulator, pixel connection analysis is performed on the insulator image to determine the insulator foreground and the insulator background, and the insulator foreground is taken as the insulator segmentation image.
[0017] Preferably, the step of analyzing the distortion degree of the insulator segmentation diagram through geometric symmetry and selecting the distorted images to be corrected includes:
[0018] Based on the pixel coordinates, the binarized insulator segmentation image is cropped to obtain the cropped insulator image.
[0019] By performing a flip analysis on the cut insulator image using geometric symmetry, a flipped insulator image is obtained.
[0020] The distortion ratio of the insulator is calculated based on the insulator flip image, and the distorted images to be corrected are selected according to the distortion ratio.
[0021] Preferably, the step of performing distortion correction processing on the distorted image to be corrected according to the perspective transformation principle to obtain the corrected insulator image includes:
[0022] The distorted image to be corrected is projected onto a new imaging plane according to the principle of perspective transformation;
[0023] The perspective transformation matrix is calculated based on the new imaging plane and the original imaging plane of the camera.
[0024] The distortion correction calculation is performed on the distorted image to be corrected using the perspective transformation matrix to obtain the corrected insulator image.
[0025] A second aspect of this application provides a device for correcting image distortion of overhead line insulators, comprising:
[0026] The image acquisition module is used to acquire images of insulators through monitoring terminals on overhead lines;
[0027] The image segmentation module is used to segment the insulator image using a preset graph theory algorithm to obtain an insulator segmentation image;
[0028] The distortion analysis module is used to analyze the degree of distortion of the insulator segmentation diagram through geometric symmetry and screen out the distorted images to be corrected.
[0029] The distortion correction module is used to perform distortion correction processing on the distorted image to be corrected according to the perspective transformation principle, so as to obtain the corrected insulator image.
[0030] Preferably, the image acquisition module is specifically used for:
[0031] Initial images are obtained through monitoring terminals on overhead power lines;
[0032] The initial image without insulators is removed based on the preset position of the camera of the monitoring terminal to obtain the filtered image;
[0033] Invalid images are removed from the filtered images based on the camera's shooting status to obtain insulator images.
[0034] Preferably, the image segmentation module is specifically used for:
[0035] Perform an insulator region bounding box annotation operation on the insulator image to obtain the insulator bounding box;
[0036] Based on the insulator annotation box and the preset Gaussian mixture model, foreground analysis is performed on the insulator image to obtain the proposed foreground and background of the insulator.
[0037] Based on the preset source node, preset sink node, the proposed foreground of the insulator, and the proposed background of the insulator, pixel connection analysis is performed on the insulator image to determine the insulator foreground and the insulator background, and the insulator foreground is taken as the insulator segmentation image.
[0038] Preferably, the distortion analysis module is specifically used for:
[0039] Based on the pixel coordinates, the binarized insulator segmentation image is cropped to obtain the cropped insulator image.
[0040] By performing a flip analysis on the cut insulator image using geometric symmetry, a flipped insulator image is obtained.
[0041] The distortion ratio of the insulator is calculated based on the insulator flip image, and the distorted images to be corrected are selected according to the distortion ratio.
[0042] Preferably, the distortion correction module is specifically used for:
[0043] The distorted image to be corrected is projected onto a new imaging plane according to the principle of perspective transformation;
[0044] The perspective transformation matrix is calculated based on the new imaging plane and the original imaging plane of the camera.
[0045] The distortion correction calculation is performed on the distorted image to be corrected using the perspective transformation matrix to obtain the corrected insulator image.
[0046] As can be seen from the above technical solutions, the embodiments of this application have the following advantages:
[0047] This application provides a method for correcting distorted images of insulators on overhead lines, comprising: acquiring insulator images through monitoring terminals on overhead lines; segmenting the insulator images using a preset graph theory algorithm to obtain segmented insulator images; analyzing the degree of distortion of the segmented insulator images using geometric symmetry to select distorted images to be corrected; and performing distortion correction processing on the distorted images to be corrected according to the principle of perspective transformation to obtain corrected insulator images.
[0048] The overhead line insulator distortion image correction method provided in this application can identify severely distorted images requiring correction by segmenting and analyzing the distortion degree of the insulator images. This avoids the excessive computational burden of correcting every image and prevents the inclusion of distorted images from affecting subsequent image analysis. Moreover, the image processing and correction processes are simple and easy to implement, meeting practical engineering requirements. Therefore, this application can solve the technical problem of distorted insulator images acquired by existing monitoring terminals on overhead lines, which affects the subsequent analysis of insulator icing status. Attached Figure Description
[0049] Figure 1 A flowchart illustrating a method for correcting image distortion of overhead line insulators, provided in an embodiment of this application;
[0050] Figure 2 A schematic diagram of the structure of an overhead line insulator distortion image correction device provided in an embodiment of this application;
[0051] Figure 3 A schematic diagram of the initial image acquired by the overhead line monitoring terminal provided in this application embodiment;
[0052] Figure 4 A schematic diagram of a foreground segmentation image provided in an embodiment of this application;
[0053] Figure 5 This is a schematic diagram of an insulator after binarization, provided in an embodiment of this application.
[0054] Figure 6 This is a schematic diagram of the foreground region trimming of an insulator provided in an embodiment of this application;
[0055] Figure 7This is a schematic diagram of an insulator flipping left and right according to an embodiment of this application;
[0056] Figure 8 This is a schematic diagram of an insulator flipping up and down according to an embodiment of this application;
[0057] Figure 9 This is a schematic diagram of the left-right flipping difference of an insulator provided in an embodiment of this application;
[0058] Figure 10 This is a schematic diagram of the insulator flipping difference provided in an embodiment of this application. Detailed Implementation
[0059] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present application.
[0060] For easier understanding, please refer to Figure 1 An embodiment of a method for correcting image distortion of overhead line insulators provided in this application includes:
[0061] Step 101: Obtain insulator images through the monitoring terminal on the overhead line.
[0062] Further, step 101 includes:
[0063] Initial images are obtained through monitoring terminals on overhead power lines;
[0064] The initial images that do not contain insulators are removed based on the preset positions of the cameras on the monitoring terminal to obtain the filtered images;
[0065] Invalid images are removed from the filtered images based on the camera's shooting status to obtain the insulator image.
[0066] Please see Figure 3 The monitoring terminal can acquire raw line images, some of which may contain insulators while others may not. To make the research and analysis in this embodiment more efficient, it is necessary to filter the acquired initial images. Camera presets can determine which images do not contain insulators, and these unqualified images can be identified, resulting in filtered images. The camera's shooting state can be understood as the camera's shooting parameters and shooting environment. Based on the influence of these factors, invalid images such as those with lens contamination, lens obstruction, blurry images, and black images can be identified in the filtered images, thereby obtaining higher-quality insulator images.
[0067] Step 102: Use a preset graph theory algorithm to segment the insulator image to obtain an insulator segmentation map.
[0068] Further, step 102 includes:
[0069] Perform insulator region bounding box annotation on the insulator image to obtain the insulator bounding box;
[0070] Foreground analysis of insulator images is performed based on insulator bounding boxes and a preset Gaussian mixture model to obtain the proposed foreground and background of insulators.
[0071] Based on the preset source node, preset sink node, proposed foreground and proposed background of the insulator, the pixel connection analysis of the insulator image is performed to determine the insulator foreground and background, and the insulator foreground is taken as the insulator segmentation image.
[0072] Graph theory algorithms provide a simple and systematic modeling approach effective for many different problems; this embodiment designs an operational scheme based on image segmentation. First, the insulator image needs to be bounded to define the insulator region, resulting in the bounding box. Next, the bounding box is used as the Region of Interest (ROI) in graph theory, meaning all pixels outside the bounding box are labeled as background, while pixels inside are left undefined. Then, a Gaussian mixture model is used to model the foreground and background. Based on the background labels of pixels outside the bounding box, unknown pixels are labeled as either possible background or possible foreground, thus obtaining the proposed foreground and background of the insulator. Then, the probability of each pixel in the insulator image belonging to the foreground or background is calculated, referred to as the belonging probability. Each pixel is connected to a preset source node and a preset sink node with an edge, the weight of which is determined by the pixel's belonging probability. Each pixel is also connected to surrounding pixels with an edge, the weight of which is determined by the similarity between the two pixels; the lower the similarity, the lower the weight. Finally, based on the maximum flow mechanism, the minimum segmentation method is used to segment the image, severing the connections between foreground and background pixels. The segmentation is based on minimizing the sum of the weights of the segmentation edges, ultimately achieving image segmentation and obtaining the insulator foreground and background. The result is as follows: Figure 4 As shown.
[0073] Step 103: Analyze the degree of distortion of the insulator segmentation diagram through geometric symmetry and screen out the distorted images to be corrected.
[0074] Further, step 103 includes:
[0075] Based on the pixel coordinates, the binarized insulator segmentation image is cropped to obtain the cropped insulator image.
[0076] By performing a flip analysis on the cut insulator image using geometric symmetry, a flipped insulator image is obtained.
[0077] The distortion ratio of the insulator is calculated based on the insulator flip image, and the distorted images to be corrected are selected according to the distortion ratio.
[0078] The binarized insulator segmentation diagram is as follows: Figure 5 As shown, the actual operation is to set the pixel value of all pixels in the insulator area to 1, and the pixel value of all pixels in other areas to 0. Please refer to [link / reference]. Figure 6 The cropping region is based on pixel coordinates, with the aim of cropping out the insulator region. The minimum, minimum, maximum, and maximum x and y coordinates of all pixels in the insulator region are found, and the four corner points of the cropping region are obtained by combining them in pairs, and then the cropping process is performed.
[0079] Since an undistorted glass insulator image is symmetrical about the horizontal or vertical axis, the distortion state can be preliminarily assessed using the principle of geometric symmetry. First, the cropped insulator image is flipped horizontally and vertically by 180°. Then, the source image and the flipped image are subtracted to obtain the horizontal and vertical subtraction difference images, i.e., the insulator flipped image. The principle of image subtraction is that the pixel value of the overlapping part is 0 after subtraction, representing black, while the absolute value of the non-overlapping part is 1, representing white. The horizontal and vertical flips are as follows: Figure 7 and Figure 8 As shown, the left-right flipped difference plot and the up-down flipped difference plot are as follows: Figure 9 and Figure 10 As shown. Next, count the number of foreground pixels in the initial insulator cropping image, denoted as M. Count the number of foreground pixels in the left-right flip difference image and the up-down flip difference image, denoted as SX and SY respectively. Then, the distortion ratio of the insulator can be calculated as:
[0080]
[0081] Wherein, k takes a value between [0,1], and in this embodiment, if k > 0.5, the insulator is considered to have a relatively serious distortion problem, and is regarded as a distorted image to be corrected.
[0082] Step 104: Perform distortion correction processing on the image to be corrected according to the principle of perspective transformation to obtain the corrected insulator image.
[0083] Further, step 104 includes:
[0084] Based on the principle of perspective transformation, the distorted image to be corrected is projected onto a new imaging plane;
[0085] Calculate the perspective transformation matrix based on the new imaging plane and the camera's original imaging plane;
[0086] The distortion correction calculation is performed on the distorted image to be corrected using the perspective transformation matrix to obtain the corrected insulator image.
[0087] The principle of perspective transformation involves the phenomenon of objects appearing larger when closer and smaller when farther away. Therefore, based on this principle, the distorted image to be corrected can be projected onto a new imaging plane, where the original imaging plane refers to the original imaging plane of the camera lens. By pre-determining four sets of corresponding points of the insulator in both the original and new imaging planes, the perspective transformation matrix can be calculated. Since the insulator skirts are of equal size and parallel, the two endpoints of the uppermost and lowermost skirts in the image can be selected as reference points. In the new imaging plane, these four points correspond to the four vertices of a rectangle. The perspective transformation matrix can be expressed as:
[0088]
[0089] Where (X / Z,Y / Z,1) are the coordinates of the pixel in the new imaging plane, and (x,y,1) are the coordinates of the pixel in the original imaging plane. Let a in the perspective transformation matrix... 33 =1, where a represents the elements of the matrix.
[0090] By iterating through the coordinates of each pixel in the new imaging plane and performing distortion correction calculations on the distorted image to be corrected using the perspective transformation matrix, we can obtain the new coordinates of each pixel on the original imaging plane, which are the corrected coordinates. The resulting image is the corrected insulator image.
[0091] The overhead line insulator distortion image correction method provided in this application can identify severely distorted images to be corrected by segmenting and analyzing the distortion degree of the insulator images. This avoids the excessive computational burden of correcting every image and prevents the presence of distorted images from affecting subsequent image analysis. Furthermore, the image processing and correction processes are simple and easy to execute, meeting practical engineering requirements. Therefore, this application can solve the technical problem of distorted insulator images acquired by existing monitoring terminals on overhead lines, which affects the subsequent analysis of insulator icing conditions.
[0092] For easier understanding, please refer to Figure 2 This application provides an embodiment of an overhead line insulator distortion image correction device, comprising:
[0093] Image acquisition module 201 is used to acquire insulator images through a monitoring terminal on an overhead line;
[0094] Image segmentation module 202 is used to segment the insulator image using a preset graph theory algorithm to obtain an insulator segmentation image;
[0095] The distortion analysis module 203 is used to analyze the degree of distortion of the insulator segmentation diagram through geometric symmetry and screen out the distorted images to be corrected.
[0096] The distortion correction module 204 is used to perform distortion correction processing on the distorted image to be corrected according to the perspective transformation principle, so as to obtain the corrected insulator image.
[0097] Furthermore, the image acquisition module 201 is specifically used for:
[0098] Initial images are obtained through monitoring terminals on overhead power lines;
[0099] The initial images that do not contain insulators are removed based on the preset positions of the cameras on the monitoring terminal to obtain the filtered images;
[0100] Invalid images are removed from the filtered images based on the camera's shooting status to obtain the insulator image.
[0101] Furthermore, the image segmentation module 202 is specifically used for:
[0102] Perform insulator region bounding box annotation on the insulator image to obtain the insulator bounding box;
[0103] Foreground analysis of insulator images is performed based on insulator bounding boxes and a preset Gaussian mixture model to obtain the proposed foreground and background of insulators.
[0104] Based on the preset source node, preset sink node, proposed foreground and proposed background of the insulator, the pixel connection analysis of the insulator image is performed to determine the insulator foreground and background, and the insulator foreground is taken as the insulator segmentation image.
[0105] Furthermore, the distortion analysis module 203 is specifically used for:
[0106] Based on the pixel coordinates, the binarized insulator segmentation image is cropped to obtain the cropped insulator image.
[0107] By performing a flip analysis on the cut insulator image using geometric symmetry, a flipped insulator image is obtained.
[0108] The distortion ratio of the insulator is calculated based on the insulator flip image, and the distorted images to be corrected are selected according to the distortion ratio.
[0109] Furthermore, the distortion correction module 204 is specifically used for:
[0110] Based on the principle of perspective transformation, the distorted image to be corrected is projected onto a new imaging plane;
[0111] Calculate the perspective transformation matrix based on the new imaging plane and the camera's original imaging plane;
[0112] The distortion correction calculation is performed on the distorted image to be corrected using the perspective transformation matrix to obtain the corrected insulator image.
[0113] In the several embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between apparatuses or units may be electrical, mechanical, or other forms.
[0114] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.
[0115] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.
[0116] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for executing all or part of the steps of the methods described in the various embodiments of this application through a computer device (which may be a personal computer, server, or network device, etc.). The aforementioned storage medium includes: USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, optical disks, and other media capable of storing program code.
[0117] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.
Claims
1. A method for correcting image distortion of overhead line insulators, characterized in that, include: Images of insulators are obtained through monitoring terminals on overhead lines; The insulator image is segmented using a pre-defined graph theory algorithm to obtain an insulator segmentation map. The specific process is as follows: Perform an insulator region bounding box annotation operation on the insulator image to obtain the insulator bounding box; Based on the insulator annotation box and the preset Gaussian mixture model, foreground analysis is performed on the insulator image to obtain the proposed foreground and background of the insulator. Based on the preset source node, preset sink node, the proposed foreground of the insulator, and the proposed background of the insulator, pixel connection analysis is performed on the insulator image to determine the insulator foreground and the insulator background, and the insulator foreground is taken as the insulator segmentation image; The distortion degree of the insulator segmentation diagram is analyzed by geometric symmetry, and the distorted images to be corrected are selected. The specific process is as follows: Based on the pixel coordinates, the binarized insulator segmentation image is cropped to obtain the cropped insulator image. By performing a flip analysis on the cut insulator image using geometric symmetry, a flipped insulator image is obtained. The distortion ratio of the insulator is calculated based on the insulator flip image, and the distorted images to be corrected are selected according to the distortion ratio. The distortion correction process is performed on the image to be corrected based on the principle of perspective transformation to obtain the corrected insulator image.
2. The method for correcting image distortion of overhead line insulators according to claim 1, characterized in that, The acquisition of insulator images via monitoring terminals on overhead lines includes: Initial images are obtained through monitoring terminals on overhead power lines; The initial image without insulators is removed based on the preset position of the camera of the monitoring terminal to obtain the filtered image; Invalid images are removed from the filtered images based on the camera's shooting status to obtain insulator images.
3. The method for correcting image distortion of overhead line insulators according to claim 1, characterized in that, The process of performing distortion correction processing on the distorted image to be corrected according to the principle of perspective transformation to obtain a corrected insulator image includes: The distorted image to be corrected is projected onto a new imaging plane according to the principle of perspective transformation; The perspective transformation matrix is calculated based on the new imaging plane and the original imaging plane of the camera. The distortion correction calculation is performed on the distorted image to be corrected using the perspective transformation matrix to obtain the corrected insulator image.
4. A device for correcting image distortion of overhead line insulators, characterized in that, include: The image acquisition module is used to acquire images of insulators through monitoring terminals on overhead lines; The image segmentation module is used to segment the insulator image using a preset graph theory algorithm to obtain an insulator segmentation image. Specifically, the image segmentation module is used for: Perform an insulator region bounding box annotation operation on the insulator image to obtain the insulator bounding box; Based on the insulator annotation box and the preset Gaussian mixture model, foreground analysis is performed on the insulator image to obtain the proposed foreground and background of the insulator. Based on the preset source node, preset sink node, the proposed foreground of the insulator, and the proposed background of the insulator, pixel connection analysis is performed on the insulator image to determine the insulator foreground and the insulator background, and the insulator foreground is taken as the insulator segmentation image; The distortion analysis module is used to analyze the degree of distortion of the insulator segmentation diagram through geometric symmetry, and to screen out the distorted images to be corrected. Specifically, the distortion analysis module is used for: Based on the pixel coordinates, the binarized insulator segmentation image is cropped to obtain the cropped insulator image. By performing a flip analysis on the cut insulator image using geometric symmetry, a flipped insulator image is obtained. The distortion ratio of the insulator is calculated based on the insulator flip image, and the distorted images to be corrected are selected according to the distortion ratio. The distortion correction module is used to perform distortion correction processing on the distorted image to be corrected according to the perspective transformation principle, so as to obtain the corrected insulator image.
5. The overhead line insulator distortion image correction device according to claim 4, characterized in that, The image acquisition module is specifically used for: Initial images are obtained through monitoring terminals on overhead power lines; The initial image without insulators is removed based on the preset position of the camera of the monitoring terminal to obtain the filtered image; Invalid images are removed from the filtered images based on the camera's shooting status to obtain insulator images.
6. The overhead line insulator distortion image correction device according to claim 4, characterized in that, The distortion correction module is specifically used for: The distorted image to be corrected is projected onto a new imaging plane according to the principle of perspective transformation; The perspective transformation matrix is calculated based on the new imaging plane and the original imaging plane of the camera. The distortion correction calculation is performed on the distorted image to be corrected using the perspective transformation matrix to obtain the corrected insulator image.