Line-scan digital camera image distortion blind correction method and system for whole rail train

Abstract

The invention discloses a blind correction method and system for image distortion of a line-scan digital camera of a whole rail train, relates to the technical field of rail transit, and solves the problem that an existing train image distortion correction method is large in error or depends on prior information. According to the technical scheme, the method is characterized in that two or more line-scan digital cameras which are not located on the same cross section are used for shooting images of the whole train, and blind correction is carried out on the train by means of the train images shot by the line-scan digital cameras at multiple angles; when the scheme is applied to the field of rail transit, scale marks do not need to be arranged on a shot train, prior information such as standard template images or train component scales and markers is not needed either, the application premise is wider, train images can be directly corrected, and the accuracy of correction is improved. And efficient and stable blind correction of the image distortion of the whole linear array camera of the rail train is realized.

Description

Technical Field

[0001] The present invention relates to the field of rail transit technology, and more specifically, to a method and system for blindly correcting image distortion of a linear array camera of a whole rail train. Background Art

[0002] In the field of rail transit, since the length of a train is much greater than its width and height, linear array cameras are often the first choice for fine imaging of the train's appearance. If the shooting frequency of a linear array camera is fixed, the linear array camera will inevitably capture distorted train images because it is impossible for a train to pass through the linear array camera at the same agreed calibration speed (i.e., the speed that matches the shooting frequency) every time.

[0003] For the above problems, on the one hand, most of the existing processing methods are to measure the speed of the train and change the shooting frequency of the linear array camera according to its instantaneous movement speed (because the linear array camera module is installed on the trackside, it is impossible to drive the linear array camera to shoot through the train's own speed module). The existing speed measurement forms are divided into two types: magnetic steel speed measurement and radar speed measurement. The magnetic steel speed measurement has high accuracy. Its principle is to calculate the train speed by using the signal time difference generated by the train wheel pair passing through the magnetic steel, so the speed measurement frequency is far from meeting the requirements; the radar speed measurement frequency is higher, but still lower than the linear array camera shooting frequency. In addition, the error percentage of radar speed measurement is high when the train is at low speed. Therefore, using the speed measurement module to perform variable frequency shooting of the train cannot fundamentally solve the distortion problem of the train image taken by the linear array camera. On the other hand, image correction can be performed through algorithms. For example, scale marks (or markers) can be set on the train, and the correction of the train image can be indirectly completed by correcting the markers; or the standard template image method can be used to match the feature information in the standard image with the feature information in the image to be corrected one by one to complete the correction of the train image. However, such schemes rely on a large amount of prior information or preconditions such as standard image templates or other train component scales and markers. Image correction cannot be performed if these prior information or preconditions are not met.

[0004] Therefore, the present application provides a method and system for blind correction of image distortion of a linear array camera of a railway train to solve the above-mentioned problems. Summary of the invention

[0005] The purpose of the present application is to provide a method and system for blind correction of image distortion of a linear array camera of a whole railway train, so as to solve the problem that the existing train image distortion correction methods have large errors or rely on prior information. The present application uses at least two linear array cameras that are not in the same cross-section to perform blind correction on synchronously shot train images, so as to realize efficient and stable train image distortion correction that is independent of prior information.

[0006] The present application first provides a method for blindly correcting image distortion of a whole-vehicle linear array camera of a railway train, comprising: S1, obtaining a plurality of train images based on synchronous shooting by at least two linear array cameras located at different sections, wherein the section refers to a cross section of the track; S2, using the linear array camera that first shoots the train image as a reference camera, and other linear array cameras as offset cameras, measuring the physical offset distance between each offset camera and the reference camera, and solving the image offset distance between each offset camera and the reference camera according to the physical offset distance and the horizontal resolution of the linear array camera imaging; S3, extracting N marking points from the train image taken by each linear array camera, and the N marking points in different train images are located in the cross section of the train; Corresponding on the surface, extracting the x coordinates of the marked points in the train images of the reference camera and the offset camera, and marking the x coordinates of the marked points in the train images of each offset camera within the coordinate range of the reference camera; S4, assuming that the correction amount of the extracted x coordinates of the marked points is an unknown amount, establishing a same-section equation with the features corresponding to the cross-sections of the marked points in the train images taken by the offset camera and the reference camera, and establishing a symmetry equation with the features symmetrical at both ends of the train; S5, establishing a linear equation group according to the same-section equation and the symmetry equation, and solving the linear equation group to obtain the correction amount; S6, transforming the N marked points in the train image taken by the linear array camera based on the correction amount to obtain the train image after distortion correction.

[0007] In a possible implementation, the same cross-section equation is: ; in, is the first The x-coordinate of the marker point 、 The first Correction amount for each marker point 、 Offset_x is the image offset between the offset camera and the reference camera. is the offset camera train image The x-coordinates of the marker points, is the offset camera train image The correction amount for each marker point.

[0008] In a possible implementation, for the correction amount of the marking point in each offset camera train image within the reference camera coordinate range, assuming that only linear distortion exists, the x-coordinate of the marking point in the reference camera train image, the correction amount of the marking point in the reference camera train image, and the x-coordinate of the marking point in the offset camera train image are expressed as: ; in, is the offset camera train image The correction amount of the marking point, The marker points are within the coordinate range of the reference camera; and is the first j and j +1 x coordinate of the marker point, and is the first j and j +1 mark point correction, is the offset camera train image The x-coordinates of the marker points are located at and between.

[0009] In a possible implementation, the symmetric equation is: ; in, and is the x-coordinate of the marker point of the specific component of the first half of the train in the reference camera image, and for and The amount of correction; and is the x-coordinate of the marker point of the same type of specific component in the second half of the group in the offset camera train image, and for and The amount of correction.

[0010] The present application also provides a system for blindly correcting image distortion of a linear array camera of a whole railway train, comprising: an image acquisition unit, used to synchronously capture multiple train images based on at least two linear array cameras located at different sections, wherein the section refers to a cross section of a track; an offset calculation unit, used to use the linear array camera that first captures the train image as a reference camera and other linear array cameras as offset cameras, measure the physical offset distance between each offset camera and the reference camera, and solve the image offset distance between each offset camera and the reference camera according to the physical offset distance and the horizontal resolution of the linear array camera imaging; a marker point extraction unit, used to extract N marker points from the train image captured by each linear array camera, and the N marker points in different train images are located in the train cross section. Corresponding to the above, the x-coordinates of the marked points in the train images of the reference camera and the offset camera are extracted, and the x-coordinates of the marked points in the train images of each offset camera that are located within the coordinate range of the reference camera are marked; a solution establishing unit is used to assume that the correction amount of the extracted x-coordinate of the marked point is an unknown amount, and to establish a same-section equation with the features corresponding to the cross-sections of the marked points in the train images taken by the offset camera and the reference camera, and to establish a symmetric equation with the features symmetrical at both ends of the train; a solution solving unit is used to establish a linear equation group according to the same-section equation and the symmetric equation, and to solve the linear equation group to obtain the correction amount; a distortion correction unit is used to transform the N marked points in the train image taken by the linear array camera based on the correction amount to obtain a train image after distortion correction.

[0011] In a possible implementation manner, in the solution building unit, the iso-section equation is: ; in, is the first The x-coordinate of the marker point 、 The first Correction amount for each marker point 、 Offset_x is the image offset between the offset camera and the reference camera. is the offset camera train image The x-coordinates of the marker points, is the offset camera train image The correction amount for each marker point.

[0012] In a possible implementation, in the solution formula establishing unit, for the correction amount of the marker points in each offset camera train image within the reference camera coordinate range, assuming that only linear distortion exists, the correction amount of the marker points in the reference camera train image, the correction amount of the marker points in the reference camera train image, and the x coordinate of the marker points in the offset camera train image are expressed as: ; in, is the offset camera train image The correction amount of the marking point, The marker points are within the coordinate range of the reference camera; and is the first j and j +1 x coordinate of the marker point, and is the first j and j +1 mark point correction, is the offset camera train image The x-coordinates of the marker points are located at and between.

[0013] In a possible implementation manner, in the solution building unit, the symmetric equation is: ; in, and is the x-coordinate of the marker point of the specific component of the first half of the train in the reference camera image, and for and The amount of correction; and is the x-coordinate of the marker point of the same type of specific component in the second half of the group in the offset camera train image, and for and The amount of correction.

[0014] The present application also provides a computer storage medium, comprising computer instructions, and when the computer instructions are executed on a mobile terminal, the mobile terminal executes the above method.

[0015] The present application also provides a computer program product, which enables the mobile terminal to execute the above method when the computer program product is executed on the mobile terminal.

[0016] Compared with the prior art, the present application has the following beneficial effects: the whole train image is captured by two or more linear array cameras that are not on the same cross-section, and the train image captured by the linear array cameras at multiple angles is used to perform blind correction on itself; when this method is applied in the field of rail transit, it does not require setting scale marks on the photographed train, nor does it require standard template images or prior information such as train component scales and markers. The application premise is more relaxed, and the train image can be directly corrected, thereby realizing efficient and stable blind correction of linear array camera image distortion of the whole rail train. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The drawings described herein are used to provide a further understanding of the embodiments of the present invention, constitute a part of this application, and do not constitute a limitation of the embodiments of the present invention. In the drawings: Figure 1 A flowchart of a method for blindly correcting image distortion of a linear array camera of a railway train provided in an embodiment of the present application; Figure 2 This is the layout diagram of the line array camera; Figure 3 Schematic diagram of the marking points of the train images taken by the reference camera and the offset camera; Figure 4 Schematic diagram of the train image taken by the reference camera and the offset camera after distortion correction; Figure 5 This is a structural diagram of the rail train vehicle linear array camera image distortion blind correction system provided in an embodiment of the present application. DETAILED DESCRIPTION

[0018] Hereinafter, the term "include" or "may include" used in various embodiments of the present application indicates the presence of the function, operation or element applied for, and does not limit the increase of one or more functions, operations or elements. In addition, as used in various embodiments of the present application, the terms "include", "have" and their cognates are intended only to indicate specific features, numbers, steps, operations, elements, components or a combination of the foregoing items, and should not be understood as first excluding the presence of one or more other features, numbers, steps, operations, elements, components or a combination of the foregoing items or the possibility of increasing one or more features, numbers, steps, operations, elements, components or a combination of the foregoing items.

[0019] The terms used in the various embodiments of the present application are only used for the purpose of describing specific embodiments and are not intended to limit the various embodiments of the present application. As used herein, the singular form is intended to also include the plural form, unless the context clearly indicates otherwise. Unless otherwise defined, all terms (including technical terms and scientific terms) used herein have the same meaning as the meanings commonly understood by ordinary technicians in the field to which the various embodiments of the present application belong. The terms (such as those defined in a generally used dictionary) will be interpreted as having the same meaning as the contextual meaning in the relevant technical field and will not be interpreted as having an idealized meaning or an overly formal meaning, unless clearly defined in the various embodiments of the present application.

[0020] In order to make the objectives, technical solutions and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with examples and drawings. The illustrative implementation scheme of the present application and its description are only used to explain the present application and are not intended to limit the present application.

[0021] See also Figure 1 As shown, Figure 1 A flow chart of a method for blind correction of image distortion of a whole-vehicle linear array camera of a rail train provided in an embodiment of the present application. The method comprises: S1, obtaining multiple train images based on synchronous shooting of at least two linear array cameras located in different cross sections, wherein the cross section refers to the cross section of the track; S2, using the linear array camera that first captures the train image as the reference camera, and other linear array cameras as offset cameras, measuring the physical offset distance between each offset camera and the reference camera, and solving the image offset distance between each offset camera and the reference camera based on the physical offset distance and the horizontal resolution of the linear array camera imaging; S3, extracting N marker points from the train image taken by each linear array camera, wherein the N marker points in different train images correspond to each other on the cross section of the train, and extracting the marker points of the reference camera and the offset camera. The x coordinates of the marked points in the train image of the offset camera are obtained, and the x coordinates of the marked points in the train image of each offset camera that are within the coordinate range of the reference camera are marked; S4, assuming that the correction amount of the extracted x coordinates of the marked points is an unknown amount, a same-section equation is established with the features corresponding to the cross-sections of the marked points in the train images taken by the offset camera and the reference camera, and a symmetric equation is established with the features symmetrical at both ends of the train; S5, a linear equation group is established according to the same-section equation and the symmetric equation, and the linear equation group is solved to obtain the correction amount; S6, based on the correction amount, the N marked points in the train image taken by the linear array camera are transformed to obtain the train image after distortion correction.

[0022] Specifically, the present application utilizes at least two linear array cameras that are not in the same cross-section to synchronously capture images of the train, establishes a same-section equation based on the actual physical position of each linear array camera in the layout, the position of the same cross-section of the train captured in each linear array camera, and an assumed correction amount, establishes a set of constraint equations based on multiple same-section equations and symmetry equations, and then solves the assumed correction amount. The correction amount obtained by the solution can be used to simultaneously correct the images captured by these linear array cameras.

[0023] The improvement of this application is that the train image is captured by two or more linear array cameras that are not on the same cross section, and the train image captured by the linear array cameras at multiple angles is used to perform blind correction on itself. When this method is applied in the field of rail transit, it does not require scale marks to be set on the photographed train, nor does it require prior information such as standard template images or train component scales and markers. The application premise is more relaxed, and the train image can be directly corrected, realizing efficient and stable blind correction of the distortion of the linear array camera image of the entire rail train.

[0024] The following takes two line scan cameras as an example (the situation of multiple line scan cameras is similar), and describes each step in detail with reference to the accompanying drawings.

[0025] Step S1 is to obtain multiple train images based on synchronous shooting of at least two linear array cameras located at different cross sections, where the cross section refers to the cross section of the track. Taking two linear array cameras as an example, before shooting the train images, the two linear array cameras are arranged on both sides of the track and on different cross sections, that is, the angle between the line connecting the two linear array cameras and the track is not perpendicular, such as Figure 2 As shown in the figure. When a train passes by, two linear array cameras synchronously shoot the train and obtain a (whole train) train image respectively. Since the speed of the train cannot meet the completely uniform speed, when the train passes by at a non-uniform speed, both linear array cameras will capture distorted train images.

[0026] Step S2 is to use the line array camera that first takes the train image as the reference camera and the other line array cameras as offset cameras to measure the physical offset distance between each offset camera and the reference camera, and solve the image offset distance between each offset camera and the reference camera according to the physical offset distance and the horizontal resolution of the line array camera imaging. Taking two line array cameras as an example, the line array camera that first takes the train image is used as the reference camera, and the other line array camera is used as the offset camera, and the physical offset distance Offset_L (unit: meter) between the offset camera and the reference camera is measured in space. According to the physical offset distance and the horizontal resolution of the line array camera imaging, the image offset distance Offset_x (unit: image pixel) between the train image taken by the offset camera and the train image taken by the reference camera is calculated in the same proportion.

[0027] Step S3 is to extract N marking points from the train images taken by each linear array camera. The N marking points in different train images correspond to each other on the cross section of the train. The x coordinates of the marking points in the train images of the reference camera and the offset camera are extracted, and the x coordinates of the marking points in the train images of each offset camera that are within the coordinate range of the reference camera are marked. Taking two linear array cameras as an example, the images taken by the two linear array cameras can be respectively marked with marking points using existing mature marking point positioning algorithms or manual labeling methods, and the x coordinates of the marking points in the images can be obtained. Marking point positioning requires ensuring that the number of marking points in the train images taken by each linear array camera is the same (e.g., each train image taken by the linear array camera has N Marking points), and the marking points correspond one-to-one on the same cross section of the train. The one-to-one correspondence here means that for a marking point in one image, a marking point that is the same as it or in the same cross section of the train can be found in other images. Marking points can be understood as characteristic points on the train, which can be the corner points of the train window, the corner points of the door, etc. After the marking points are located, the x coordinates of all marking points in their respective images are recorded. Figure 3 As shown, the coordinates of the marked points in the reference camera train image are recorded in ascending order as , the coordinates of the marker points in the offset camera train image are . Extract the x coordinates of all the markers of the reference camera train image and the x coordinates of the markers of the offset camera train image outside the above coordinate range. .here .

[0028] Step S4 is to assume that the correction amount of the x-coordinate of the extracted marker point is an unknown amount, and to establish a same-section equation based on the features corresponding to the sections of the marker points in the train images taken by the offset camera and the reference camera, and to establish a symmetric equation based on the features symmetrical at both ends of the train. The correction amount is recorded as , with the correction amount as the unknown quantity. Here, the last marker point in the offset camera train image is fixed, and the correction amount of this marker point is 0, that is, The image stretching / compression transformation and image offset corresponding to the correction amount are used to correct the image distortion of the two linear array cameras. N Establish the same cross-section equation for each marked point.

[0029] In a possible implementation, the same cross-section equation is: (1) in, is the first The x-coordinate of the marker point 、 The first Correction amount for each marker point、 Offset_x is the image offset between the offset camera and the reference camera. is the offset camera train image The x-coordinates of the marker points, is the offset camera train image The correction amount for each marker point.

[0030] In a possible implementation, for the correction amount of the marking point in each offset camera train image within the reference camera coordinate range, assuming that only linear distortion exists, the x-coordinate of the marking point in the reference camera train image, the correction amount of the marking point in the reference camera train image, and the x-coordinate of the marking point in the offset camera train image are expressed as: (2) in, is the offset camera train image The correction amount of the marking point, The marker points are within the coordinate range of the reference camera; and is the first j and j +1 x coordinate of the marker point, and is the first j and j +1 mark point correction, is the offset camera train image The x-coordinates of the marker points are located at and The meaning of formula 2 is, The position in the image is placed and Between, assuming and There is only linear distortion between Correction amount The unknown quantity and unknown quantity The decision is an expression of a linear transformation.

[0031] In addition, if the train has the property of head-to-tail symmetry (such as the common A1-B1-C1-C2-B2-A2 six-carriage form, A1 and A2 are the end cars with the driver's cab, B1 and B2 are the near-end cars containing the power equipment, and C1 and C2 are the middle cars for transporting passengers), a series of symmetry equations can also be established based on the symmetry characteristics of the train. Figure 3 The front and rear of the train are symmetrical, that is, the length of a specific component at the front of the train is equal to the length of the same specific component at the rear of the train.

[0032] In a possible implementation, the symmetric equation is: (3) in, and is the x-coordinate of the marker point of the specific component of the first half of the train in the reference camera image, and for and The amount of correction; and is the x-coordinate of the marker point of the same type of specific component in the second half of the group in the offset camera train image, and for and The meaning of this equation is that a certain component appears in both the front and rear halves of the train, and its corrected images have the same length at the pixel point. Here, multiple sets of similar equations can be established based on the symmetry information of the train.

[0033] Step S5 is to establish a linear equation system based on the same-section equation and the symmetric equation, and solve the linear equation system to obtain the correction amount. All the same-section equations and symmetric equations are established as a linear equation system, and the linear equation system is solved to obtain the correction amount assumed in step S4. The same-section equation and the symmetric equation are rewritten in the form of matrix rows: (4) in, and b is a constant, is the correction amount. The form of the matrix row is composed of all formulas (1) and (3) together, and for the correction amount of the marker point without assumption Substitute into formula (2). For example: when When , equation (1) can be written as: ; when When , formula (2) is substituted into formula (1), it can be written as: ; Formulate all the above matrix row equations as a linear system of equations Here y for . Solve the linear equations to obtain the correction value.

[0034] Step S6 is to transform the N marking points in the train image captured by the linear array camera based on the correction amount to obtain a train image after distortion correction. , coordinate transformation is performed on all the marking points located in step S3 to complete the image distortion correction. Figure 4 As shown, after the train images taken by the reference camera and the offset camera are distorted, the positions of the two images on the same section form a standard one-to-one correspondence, and the distorted image is well restored.

[0035] It can be understood that the method for blind correction of image distortion of a whole-vehicle linear array camera of a rail train provided in the present application uses train images taken by at least two linear array cameras that are not in the same cross-section to perform blind correction on themselves. It does not require standard image templates or other prior information or prerequisites such as the scales and markers of other train components, and achieves train image distortion correction more efficiently and stably.

[0036] See also Figure 5 As shown, Figure 5 A structural diagram of a blind correction system for image distortion of a linear array camera of a whole railway train provided in an embodiment of the present application. The system is used to implement the above method. It includes: an image acquisition unit, used to obtain multiple train images based on synchronous shooting of at least two linear array cameras located in different sections, and the section refers to the cross section of the track; an offset calculation unit, used to use the linear array camera that first captures the train image as the reference camera, and other linear array cameras as offset cameras, to measure the physical offset distance between each offset camera and the reference camera, and solve the image offset distance between each offset camera and the reference camera according to the physical offset distance and the horizontal resolution of the linear array camera imaging; a marker point extraction unit, used to extract N marker points from the train image taken by each linear array camera, and the N marker points in different train images correspond to each other on the cross section of the train, and extract the marker points between the reference camera and the offset camera. The invention relates to a method for extracting an x-coordinate of a marked point in a train image of a linear array camera, and marking the x-coordinate of the marked point in each offset camera train image within the coordinate range of the reference camera; a solution establishing unit, used for assuming that the correction amount of the extracted x-coordinate of the marked point is an unknown amount, establishing a same-section equation with the features corresponding to the cross-section of the marked point in the train image taken by the offset camera and the reference camera, and establishing a symmetric equation with the features symmetrical at both ends of the train; a solution solving unit, used for establishing a linear equation group according to the same-section equation and the symmetric equation, and solving the linear equation group to obtain the correction amount; a distortion correction unit, used for transforming the N marked points in the train image taken by the linear array camera based on the correction amount to obtain a train image after distortion correction.

[0037] In a possible implementation manner, in the solution building unit, the iso-section equation is: ; in, is the first The x-coordinate of the marker point 、 The first Correction amount for each marker point 、 Offset_x is the image offset between the offset camera and the reference camera. is the offset camera train image The x-coordinates of the marker points, is the offset camera train image The correction amount for each marker point.

[0038] In a possible implementation, in the solution formula establishing unit, for the correction amount of the marker points in each offset camera train image within the reference camera coordinate range, assuming that only linear distortion exists, the correction amount of the marker points in the reference camera train image, the correction amount of the marker points in the reference camera train image, and the x coordinate of the marker points in the offset camera train image are expressed as: ; in, is the offset camera train image The correction amount of the marking point, The marker points are within the coordinate range of the reference camera; and is the first j and j +1 x coordinate of the marker point, and is the first j and j +1 mark point correction, is the offset camera train image The x-coordinates of the marker points are located at and between.

[0039] In a possible implementation manner, in the solution building unit, the symmetric equation is: ; in, and is the x-coordinate of the marker point of the specific component of the first half of the train in the reference camera image, and for and The amount of correction; and is the x-coordinate of the marker point of the same type of specific component in the second half of the group in the offset camera train image, and for and The amount of correction.

[0040] It should be noted that the rail train vehicle linear array camera image distortion blind correction system provided in the present application is used to implement the above-mentioned rail train vehicle linear array camera image distortion blind correction method, corresponds one-to-one to the above-mentioned method, and has corresponding technical effects, so it will not be elaborated on.

[0041] An embodiment of the present application also provides a computer storage medium, including computer instructions, which, when executed on a mobile terminal, causes the mobile terminal to execute the above method.

[0042] The embodiment of the present application also provides a computer program product, which enables the mobile terminal to execute the above method when the computer program product is executed on the mobile terminal.

[0043] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for blind correction of image distortion of a linear array camera of a railway train, characterized in that: include: A plurality of train images are obtained by synchronously photographing at least two linear array cameras located at different sections, wherein the section refers to a track cross section; The linear array camera that first captures the train image is used as the reference camera, and the other linear array cameras are used as offset cameras. The physical offset distance between each offset camera and the reference camera is measured, and the image offset distance between each offset camera and the reference camera is solved according to the physical offset distance and the horizontal resolution of the linear array camera imaging. Extract N marking points from the train images taken by each linear array camera, the N marking points in different train images correspond to each other on the train cross section, extract the x coordinates of the marking points in the train images of the reference camera and the offset camera, and mark the x coordinates of the marking points in the train images of each offset camera within the coordinate range of the reference camera; Assuming that the correction amount of the x-coordinate of the extracted marker point is an unknown quantity, the same section equation is established with the features corresponding to the sections of the marker points in the train images taken by the offset camera and the reference camera, and the symmetry equation is established with the features symmetrical at both ends of the train; Establish a linear equation system according to the same-section equation and the symmetry equation, and solve the linear equation system to obtain a correction amount; Based on the correction amount, N marking points in the train image taken by the linear array camera are transformed to obtain a distortion-corrected train image.

2. According to claim 1, a method for blind correction of image distortion of a linear array camera of a railway train, characterized in that: The iso-section equation is: ； in, is the first The x-coordinate of the marker point 、 The first Correction amount for each marker point 、 Offset_x is the image offset between the offset camera and the reference camera. is the offset camera train image The x-coordinates of the marker points, is the offset camera train image The correction amount for each marker point.

3. According to claim 2, a method for blindly correcting image distortion of a linear array camera of a railway train, characterized in that: For the correction amount of the marker points in each offset camera train image within the reference camera coordinate range, assuming that only linear distortion exists, the x-coordinate of the marker point in the reference camera train image, the correction amount of the marker point in the reference camera train image, and the x-coordinate of the marker point in the offset camera train image are expressed as: ； in, is the offset camera train image The correction amount of the marking point, The marker points are within the coordinate range of the reference camera; and is the first j and j +1 x coordinate of the marker point, and is the first j and j +1 mark point correction, is the offset camera train image The x-coordinates of the marker points are located at and between.

4. The method for blindly correcting image distortion of a linear array camera of a railway train according to claim 1, characterized in that: The symmetric equation is: ； in, and is the x-coordinate of the marker point of the specific component of the first half of the train in the reference camera image, and for and The amount of correction; and is the x-coordinate of the marker point of the same type of specific component in the second half of the group in the offset camera train image, and for and The amount of correction.

5. A blind correction system for image distortion of a linear array camera of a railway train, characterized in that: A method for blindly correcting image distortion of a linear array camera of a whole railway train according to any one of claims 1 to 4, comprising: An image acquisition unit, configured to obtain a plurality of train images based on synchronous shooting by at least two linear array cameras located at different sections, wherein the section refers to a track cross section; An offset obtaining unit is used to use the linear array camera that first captures the train image as a reference camera and other linear array cameras as offset cameras, measure the physical offset distance between each offset camera and the reference camera, and calculate the image offset distance between each offset camera and the reference camera according to the physical offset distance and the horizontal resolution of the linear array camera imaging; A marker point extraction unit is used to extract N marker points from the train images taken by each linear array camera, wherein the N marker points in different train images correspond to each other on the train cross section, extract the x coordinates of the marker points in the train images of the reference camera and the offset camera, and mark the x coordinates of the marker points in the train images of each offset camera that are within the coordinate range of the reference camera; A solution formula establishment unit is used to assume that the correction amount of the extracted marker point x-coordinate is an unknown amount, establish a same-section equation with features corresponding to the marker point cross section in the train image taken by the offset camera and the reference camera, and establish a symmetric equation with features symmetrical at both ends of the train; A solution-solving unit, used for establishing a linear equation system according to the iso-section equation and the symmetry equation, and solving the linear equation system to obtain a correction amount; The distortion correction unit is used to transform the N marking points in the train image taken by the linear array camera based on the correction amount to obtain a train image after distortion correction.

6. The system for blindly correcting image distortion of a linear array camera of a railway train according to claim 5, characterized in that: In the solution building unit, the iso-section equation is: ； in, is the first The x-coordinate of the marker point 、 The first Correction amount for each marker point 、 Offset_x is the image offset between the offset camera and the reference camera. is the offset camera train image The x-coordinates of the marker points, is the offset camera train image The correction amount for each marker point.

7. The system for blindly correcting image distortion of a linear array camera of a railway train according to claim 6, characterized in that: In the solution formula establishment unit, for the correction amount of the marking point in each offset camera train image within the reference camera coordinate range, assuming that only linear distortion exists, the correction amount of the marking point in the reference camera train image, the correction amount of the marking point in the reference camera train image, and the x coordinate of the marking point in the offset camera train image are expressed as: ； in, is the offset camera train image The correction amount of the marking point, The marker points are within the coordinate range of the reference camera; and is the first j and j +1 x coordinate of the marker point, and is the first j and j +1 mark point correction, is the offset camera train image The x-coordinates of the marker points are located at and between.

8. The system for blindly correcting image distortion of a linear array camera of a railway train according to claim 5, characterized in that: In the solution building unit, the symmetric equation is: ； in, and is the x-coordinate of the marker point of the specific component of the first half of the train in the reference camera image, and for and The amount of correction; and is the x-coordinate of the marker point of the same type of specific component in the second half of the group in the offset camera train image, and for and The amount of correction.

9. A computer storage medium, characterized in that The method comprises computer instructions, which, when executed on a mobile terminal, enable the mobile terminal to execute a method for blindly correcting image distortion of a linear array camera of a whole vehicle of a railway train as claimed in any one of claims 1 to 4.

10. A computer program product, characterized in that When the computer program product runs on a mobile terminal, the mobile terminal executes a method for blindly correcting image distortion of a linear array camera of a railway train as described in any one of claims 1 to 4.

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