A method, device and medium for identifying tire ink imprints

Abstract

The present application discloses a method, device and medium for identifying tire ink imprints, scanning the original image of the ink imprints, and preprocessing the scanned image of the ink imprints to obtain a preprocessed imprint image; the preprocessing includes color model parameter adjustment, median filtering processing and binarization processing; fitting the imprint contours corresponding to all imprint areas in the imprint image, and generating an adjusted imprint contour in response to a dragging operation of the user on the imprint contour; taking all the adjusted imprint contours as a whole, fitting the minimum circumscribed polygon corresponding to the whole of the imprint contours, and automatically extracting the imprint geometric features; in response to a selection operation of the user on a measurement point, determining the corresponding target measurement point, and calculating the imprint length at the position where the target measurement point is located based on the minimum circumscribed polygon.

Description

Technical Field

[0001] The present application relates to the technical field of data processing, and particularly to a method, device, and medium for identifying tire ink imprints. Background Art

[0002] Currently, in the development process of the automotive industry, as a key medium for the interaction between the vehicle and the road surface, the performance of tires is directly related to the overall handling stability, braking efficiency, and riding comfort of the vehicle. With the continuous progress of automotive technology and the increasing requirements of consumers for driving experience, in-depth research and optimization of tire grounding performance have become particularly important. The geometric characteristics and pressure distribution characteristics of the tire when it is in contact with the ground not only reflect the design and manufacturing level of the tire itself but also directly affect the driving performance of the vehicle under various road conditions.

[0003] The tire grounding imprint, as a direct basis for evaluating tire performance, its precise measurement and analysis technology has always been a hot topic in the fields of tire research and development and vehicle dynamics research. The geometric characteristics of the imprint, such as the imprint area, actual contact area, imprint length, imprint width, and rectangular ratio, that is, the aspect ratio of the imprint length to the width, provide valuable feedback information for tire designers, which helps to optimize the tire structure, material formula, and tread pattern design, thereby improving the comprehensive performance of the tire.

[0004] With the development of computer vision, existing technologies can process tire ink imprint images through image recognition technology, extract the geometric characteristics of the tire, and analyze the grounding performance of the tire. However, most of the existing ink imprint analysis and processing software cannot distinguish the imprint area from impurity areas such as marks, cannot manually adjust the imprint contour, and cannot independently select the measurement position, thus affecting the analysis accuracy. Summary of the Invention

[0005] Embodiments of the present application provide a method, device, and medium for identifying tire ink imprints to solve the above technical problems.

[0006] On the one hand, embodiments of the present application provide a method for identifying tire ink imprints, including:

[0007] Scanning the original image of the ink imprint and preprocessing the scanned image of the ink imprint to obtain a preprocessed imprint image; the preprocessing includes color model parameter adjustment, median filtering, and binarization;

[0008] Fitting the imprint contours corresponding to all imprint areas in the imprint image, and generating an adjusted imprint contour in response to the user's dragging operation on the imprint contour;

[0009] Taking all the adjusted imprint contours as a whole, fitting the minimum circumscribed polygon corresponding to the whole of the imprint contours, and automatically extracting the imprint geometric characteristics;

[0010] In response to a user's selection operation for a measurement point, determine a corresponding target measurement point, and calculate the imprint length at the position where the target measurement point is located based on the minimum circumscribed polygon.

[0011] In one implementation manner of the present application, scan the original image of the ink imprint, and preprocess the scanned image of the ink imprint to obtain a preprocessed imprint image, specifically including:

[0012] Obtain the original image of the ink imprint, and scan the original image to obtain a corresponding scanned image of the ink imprint;

[0013] Perform color filtering on the scanned image of the ink imprint, and perform median filtering on the imprint image after color filtering;

[0014] Perform binarization processing on the imprint image after color filtering and filtering to obtain a preprocessed imprint image.

[0015] In one implementation manner of the present application, perform color filtering on the scanned image of the ink imprint, and perform median filtering on the imprint image after color filtering, specifically including:

[0016] Adjust the model parameters in the corresponding color model of the scanned image of the ink imprint to perform color filtering on the scanned image of the ink imprint, and extract the imprint image corresponding to the imprint area in the scanned image of the ink imprint after color filtering;

[0017] Based on the filter kernel, perform filtering on the imprint area in the imprint image after color filtering to remove the image edge noise in the imprint image.

[0018] In one implementation manner of the present application, after generating an adjusted imprint contour in response to a user's dragging operation on the imprint contour, the method further includes:

[0019] Calculate the sum of the areas of the pixel points corresponding to the grounded parts of all the adjusted imprint contours to obtain the pixel grounded area of the enclosed area corresponding to all the adjusted imprint contours;

[0020] Obtain the actual paper area of the paper corresponding to the scanned image of the ink imprint, as well as the pixel paper length and pixel paper width corresponding to the paper, and calculate the pixel paper area corresponding to the paper according to the pixel paper length and the pixel paper width;

[0021] Determine the ratio of the pixel grounded area to the pixel paper area, and calculate the actual grounded area corresponding to the ink imprint according to the product of the ratio of the grounded paper area and the actual paper area.

[0022] In an implementation manner of the present application, after taking all the adjusted imprint contours as a whole and fitting the minimum circumscribed polygon corresponding to the whole imprint contour, the method further includes:

[0023] Calculating the sum of the areas of the pixel points of the imprint part corresponding to the minimum circumscribed polygon to obtain the pixel imprint area corresponding to the whole imprint contour;

[0024] Determining the imprint paper area ratio between the pixel imprint area and the pixel paper area, and calculating the actual imprint area corresponding to the whole imprint contour according to the product of the imprint paper area ratio and the actual paper area.

[0025] In an implementation manner of the present application, after taking all the adjusted imprint contours as a whole and fitting the minimum circumscribed polygon corresponding to the whole imprint contour, the method further includes:

[0026] Fitting the minimum circumscribed rectangle corresponding to the whole imprint contour, and determining the imprint length and imprint width of the whole imprint contour according to the length and width of the minimum circumscribed rectangle;

[0027] Obtaining the actual paper length and actual paper width of the paper corresponding to the ink imprint scanned image, and determining the longitudinal position to be measured in the minimum circumscribed rectangle;

[0028] Determining the pixel imprint length based on the line segment length between the intersection points of the line corresponding to the longitudinal position to be measured and the minimum circumscribed polygon;

[0029] Determining the imprint paper length ratio between the pixel imprint length and the pixel paper length, and determining the actual imprint length corresponding to the whole imprint contour according to the product of the imprint paper length ratio and the actual paper length;

[0030] Determining the horizontal side length of the minimum circumscribed rectangle, and determining the actual imprint width corresponding to the whole imprint contour according to the horizontal side length.

[0031] In an implementation manner of the present application, after fitting the minimum circumscribed rectangle corresponding to the whole imprint contour, the method further includes:

[0032] Identifying the imprint contour in the minimum circumscribed rectangle, determining the coordinates of the leftmost endpoint and the rightmost endpoint corresponding to the imprint contour, and calculating the abscissa corresponding to the center position of all the imprint contours according to the abscissa of the leftmost endpoint and the abscissa of the rightmost endpoint to determine the center position imprint length;

[0033] Based on the abscissa corresponding to the central position, determine the imprint lengths at the specified left and right positions of all imprint contours, calculate the sum of the imprint lengths at the specified left and right positions, and calculate the rectangle ratio corresponding to the entire imprint area based on the central position imprint length and the sum of the imprint lengths at the specified left and right positions.

[0034] In one implementation of the present application, fit the imprint contours corresponding to all imprint areas in the imprint image, and generate an adjusted imprint contour in response to a user's dragging operation on the imprint contour, specifically including:

[0035] Generate a transparent layer with the same size as the original image of the ink imprint, and overlay the transparent layer on the original image;

[0036] Fit the imprint contour on the original image and display the fitted imprint contour on the transparent layer;

[0037] According to a preset division rule, longitudinally divide the minimum circumscribed polygon into multiple longitudinal contours to obtain corresponding multiple equal division points, and insert the multiple equal division points into the vertex coordinate set corresponding to the minimum circumscribed polygon;

[0038] Receive a user's dragging operation request for the imprint contour, and use all points in the vertex coordinate set as the recognition points for the dragging operation request;

[0039] In response to the dragging operation request, determine the recognition points corresponding to the dragging operation request, and adjust the corresponding imprint contour according to the recognition points to generate an adjusted imprint contour.

[0040] On the other hand, an embodiment of the present application further provides a tire ink imprint recognition device, and the device includes:

[0041] At least one processor;

[0042] And a memory communicatively connected to the at least one processor;

[0043] Wherein, the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to execute a tire ink imprint recognition method as described above.

[0044] On the other hand, an embodiment of the present application further provides a non-volatile computer storage medium storing computer-executable instructions, and when the computer-executable instructions are executed, a tire ink imprint recognition method as described above is implemented.

[0045] The embodiments of the present application provide a method, device, and medium for identifying tire ink imprints, which at least have the following beneficial effects:

[0046] By adjusting the color model parameters, the contrast between the imprint and the background can be enhanced, making the imprint more prominent; median filtering can effectively remove noise in the image and improve the clarity of the image; and binarization can simplify the image into black and white, facilitating subsequent contour recognition and processing, thereby improving the accuracy and efficiency of imprint recognition; by automatically fitting the imprint contour, the time for manual sketching by the user can be saved and the work efficiency can be improved; at the same time, the user is allowed to drag and adjust the contour, enhancing the flexibility and accuracy of the operation and making the imprint contour more in line with the actual needs; by fitting the minimum circumscribed polygon, it is convenient for subsequent calculations and analyses; and allowing the user to select measurement points makes the measurement more targeted and practical, meeting the measurement needs in different scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The schematic embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation to the present application. In the drawings:

[0048] Figure 1 is a schematic flowchart of a method for identifying tire ink imprints provided by an embodiment of the present application;

[0049] Figure 2 is a schematic diagram of a binarized imprint image provided by an embodiment of the present application;

[0050] Figure 3 is a schematic diagram of an unadjusted minimum circumscribed polygon provided by an embodiment of the present application;

[0051] Figure 4 is a schematic diagram of an adjusted minimum circumscribed polygon provided by an embodiment of the present application;

[0052] Figure 5 is a schematic diagram of the internal structure of a device for identifying tire ink imprints provided by an embodiment of the present application. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0053] To make the objectives, technical solutions, and advantages of the present application clearer, the technical solutions of the present application will be clearly and completely described below in conjunction with the specific embodiments of the present application and the corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.

[0054] The following will describe in detail the technical solutions provided by each embodiment of the present application in conjunction with the accompanying drawings.

[0055] Figure 1 It is a schematic flowchart of a method for identifying tire ink imprints provided by an embodiment of the present application.

[0056] The implementation of the analysis method involved in the embodiments of the present application can be a terminal device or a server, and the present application does not make special restrictions on this. For the convenience of understanding and description, the following embodiments will be described in detail taking the server as an example.

[0057] It should be noted that the server can be a single device or a system composed of multiple devices, that is, a distributed server, and the present application does not make specific limitations on this.

[0058] As Figure 1 shown, a method for identifying tire ink imprints provided by an embodiment of the present application includes:

[0059] 101. Scan the original image of the ink imprint and preprocess the scanned image of the ink imprint to obtain a preprocessed imprint image. It should be noted that the preprocessing in the embodiments of the present application includes color model parameter adjustment, median filtering processing, and binarization processing.

[0060] The visualization program interface designed by the present application using the PyQt package has functions such as importing pictures, selecting paper sizes, imprint analysis, result display, and saving. The tire forward direction in the imported scanned image of the ink imprint may be along the vertical or horizontal direction of the screen. To make the recognition and calculation results more accurate, the present application adds a button for image rotation to keep the tire forward direction in the scanned image of the ink imprint always along the vertical direction of the screen. In addition, to make the imported scanned image of the ink imprint adapt to the size of the program window, the present application scales the image. Therefore, the longitudinal or horizontal scaling ratio of the image should also be considered when analyzing and calculating the geometric parameters of the imprint.

[0061] Specifically, in an embodiment of the present application, scanning the original image of the ink imprint and preprocessing the scanned image of the ink imprint to obtain a preprocessed imprint image specifically includes:

[0062] Obtain the original image of the ink imprint and scan the original image to obtain a corresponding scanned image of the ink imprint;

[0063] Perform color filtering on the scanned image of the ink imprint and perform median filtering processing on the imprint image after color filtering;

[0064] Perform binarization processing on the imprint image after color filtering and filtering to obtain a preprocessed imprint image.

[0065] In one embodiment, a high-resolution digital camera or scanner is used to photograph or scan the ink imprint left by the tire during the test. Ensure that the light in the photographing environment is uniform to avoid the influence of shadows and reflections on the image quality. Save the photographed or scanned image in a digital format such as JPEG, PNG, or TIFF for subsequent processing.

[0066] If a scanner is used, directly import the original image file into the scanning software and perform scanning settings such as resolution, color mode, etc. If a photograph taken by a digital camera is used, there is no need to scan again and it can directly enter the next color filtering process. After scanning is completed, save the scanned ink imprint image to ensure that the image is clear and distortion-free.

[0067] The ink imprint image obtained by scanning often has impurities such as handwriting and stains. If not processed, it will interfere with the image recognition of the imprint area. Therefore, import the scanned ink imprint image into the program and adjust the parameters of the color model according to the color characteristics of the ink imprint to highlight the imprint area and remove background interference. After color filtering, save the obtained imprint image to ensure that the imprint area is clearly distinguishable. Perform median filtering on the imprint image after color filtering to remove noise and speckles in the image while retaining the outline and details of the imprint. After filtering, save the obtained filtered imprint image to ensure that the image is smooth and the imprint outline is clear.

[0068] Binarization is to set the grayscale value of the pixel points on the image to 0 or 255, making the entire image show an obvious black-and-white effect. It can effectively distinguish the target area and the background area, enhance the image contrast and features, facilitate subsequent image analysis and processing, and can also greatly reduce the data volume, saving storage and calculation costs. This application adopts the OTSU binarization method, and the obtained segmentation threshold can maximize the variance between the foreground and the background and is computationally simple. Perform binarization on the imprint image after color filtering and filtering to convert the image into a binary image containing only black and white. In the binary image, the imprint area is black and the background is white. After binarization, save the obtained preprocessed imprint image, which will be used for subsequent analysis and processing such as contour fitting and area calculation.

[0069] In one embodiment of the present application, color filtering is performed on the scanned ink imprint image, and median filtering is performed on the imprint image after color filtering, specifically including:

[0070] Adjust the model parameters in the corresponding color model of the scanned ink imprint image to perform color filtering on the scanned ink imprint image and extract the imprint image corresponding to the imprint area in the scanned ink imprint image after color filtering;

[0071] Based on the filter kernel, filter the imprint area in the color-filtered imprint image to remove the image edge noise in the imprint image.

[0072] In one embodiment, HSV is a color space created based on the intuitive characteristics of colors, also known as the hexagonal pyramid model. In the HSV model, color is composed of hue, saturation, and value. By adjusting the H, S, and V parameters, the image of the imprint area can be enhanced, and the image of impurities different from the imprint color can be weakened, so as to achieve the effect of color filtering for the image.

[0073] Median filtering is a non-linear filtering method. Take the pixel values of the current pixel point and its surrounding pixel points (a total of an odd number of pixel points), sort them, and use the value at the middle position as the pixel value of the current pixel point. The noise elimination effect of median filtering is relatively good, but as the filter kernel increases, the image will also become blurred. In this work, a 5*5 filter kernel is used to filter the masked area after HSV color filtering to achieve the effect of eliminating image edge noise.

[0074] Figure 2 This is a schematic diagram of the binarized imprint image provided by the embodiment of the present application. As Figure 2 shown, the original image of the ink imprint is subjected to color filtering and filtering processing, and further through binarization processing, a binarized black and white imprint image is obtained, so as to facilitate the subsequent calculation of the actual grounding area of the ink imprint in the black and white imprint image.

[0075] 102. Fit the imprint contours corresponding to all imprint areas in the imprint image, and generate an adjusted imprint contour in response to the user's dragging operation on the imprint contour.

[0076] Specifically, in one embodiment of the present application, fitting the imprint contours corresponding to all imprint areas in the imprint image, and generating an adjusted imprint contour in response to the user's dragging operation on the imprint contour specifically includes:

[0077] Generate a transparent layer with the same size as the original image of the ink imprint, and superimpose the transparent layer on the original image;

[0078] Fit the imprint contour on the original image and display the fitted imprint contour on the transparent layer;

[0079] Divide the imprint contour into upper and lower equal parts, determine the corresponding equal division points, and insert the equal division points into the vertex coordinate set corresponding to the minimum circumscribed polygon;

[0080] Receive the user's dragging operation request for the imprint contour, and use all the points in the vertex coordinate set as the recognition points for the dragging operation request;

[0081] In response to a drag operation request, identify the recognition points corresponding to the drag operation request, and adjust the corresponding imprint contour according to the recognition points to generate an adjusted imprint contour.

[0082] In one embodiment, the present application uses the minimum convex polygon to fit the imprint contour. This method has accurate fitting and fast calculation speed. However, for imprints with depressions such as butterfly-shaped ones, there will be relatively large errors in the fitting results. Therefore, this work adds a function for manually adjusting the contour. First, overlay a transparent layer of the same size as the original image on the imported image, and display, adjust, and update the fitted contour on this transparent layer.

[0083] The fitted minimum convex polygon returns a set of vertex coordinates of the convex polygon. To enable the mouse to more flexibly identify and adjust the contour, the present application also calculates the 30 equal division points of the upper and lower contours, adds the equal division points to the set of vertex coordinates, and interpolates the set of vertex coordinates. When adjusting the contour, first identify the nearest point in the set of vertex coordinates to the position of the mouse. After dragging the mouse to the target position, update the set of vertex coordinates, and then redraw the contour connected end to end. After the imprint contour is updated, the geometric parameter features will also be recalculated and output.

[0084] In one embodiment of the present application, after generating an adjusted imprint contour in response to a user's drag operation on the imprint contour, it includes:

[0085] Calculate the sum of the areas of the pixel points of the grounded parts corresponding to all the adjusted imprint contours to obtain the pixel grounded area of the enclosed area corresponding to all the adjusted imprint contours;

[0086] Obtain the actual paper area of the paper corresponding to the ink imprint scan image, as well as the pixel paper length and pixel paper width corresponding to the paper, and calculate the pixel paper area corresponding to the paper according to the pixel paper length and pixel paper width;

[0087] Determine the ratio of the grounded paper area between the pixel grounded area and the pixel paper area, and calculate the actual grounded area corresponding to the ink imprint according to the product of the grounded paper area ratio and the actual paper area.

[0088] In one embodiment, extract the red imprint part in the imprint scan image, use the Opencv package to fit the contour, and calculate the pixel area of the enclosed area of the contour. The sum of all pixel areas is regarded as the pixel area of the entire grounded part, and then calculate the actual grounded area of the ink imprint according to the ratio of the grounded pixel area to the pixel area of the entire image. The specific calculation formula is:

[0089]

[0090] It should be noted that S in the embodiments of the present applicationgt Represents the actual grounding area of the ink imprint, in square centimeters (cm2), S pt Represents the actual paper area, in square centimeters (cm2), S PP Represents the pixel paper area, which is the sum of the areas of all pixel points on the entire paper and is determined by the product of the pixel length and pixel width of the paper, S gp Represents the pixel grounding area, which is the sum of the areas of all grounded pixel points of the ink imprint.

[0091] 103. Take all the adjusted imprint contours as a whole, fit the minimum circumscribed polygon corresponding to the entire imprint contour, and automatically extract the geometric features of the imprint.

[0092] It should be noted that the geometric features of the imprint in the embodiments of this application include, for example: grounding area, imprint area, imprint length, imprint width, and rectangle ratio, etc.

[0093] In an embodiment of this application, after taking all the adjusted imprint contours as a whole and fitting the minimum circumscribed polygon corresponding to the entire imprint contour, it includes:

[0094] Calculate the sum of the areas of the pixel points corresponding to the imprint part of the minimum circumscribed polygon to obtain the pixel imprint area corresponding to the entire imprint contour;

[0095] Determine the ratio of the imprint paper area between the pixel imprint area and the pixel paper area, and calculate the actual imprint area corresponding to the entire imprint contour according to the product between the imprint paper area ratio and the actual paper area.

[0096] In an embodiment, the calculation method of the imprint area of the entire imprint area is as follows: First, take all the imprint contours as a whole, fit the minimum circumscribed convex polygon corresponding to the entire contour, and calculate the pixel imprint area corresponding to the minimum circumscribed convex polygon. Similarly, calculate the imprint area corresponding to the entire imprint area according to the proportion of the polygon pixel imprint area in the entire paper pixel area. The specific calculation formula is:

[0097]

[0098] It should be noted that S in the embodiments of this application ft Represents the actual imprint area, in square centimeters (cm2), S fp Represents the pixel imprint area, which is the sum of the areas of all pixel points of the imprint part.

[0099] In an embodiment of this application, after taking all the adjusted imprint contours as a whole and fitting the minimum circumscribed polygon corresponding to the entire imprint contour, it includes:

[0100] Fit the minimum bounding rectangle corresponding to the overall ink imprint contour, and determine the imprint length and imprint width of the overall ink imprint contour according to the length and width of the minimum bounding rectangle;

[0101] Obtain the actual paper length and actual paper width of the paper corresponding to the scanned image of the ink imprint, and determine the longitudinal position to be measured in the minimum bounding rectangle;

[0102] Based on the length of the line segment between the intersections of the line corresponding to the longitudinal position to be measured and the minimum circumscribed polygon, determine the pixel imprint length;

[0103] Determine the imprint paper length ratio between the pixel imprint length and the pixel paper length, and determine the actual imprint length corresponding to the overall ink imprint contour according to the product of the imprint paper length ratio and the actual paper length;

[0104] Determine the horizontal side length of the minimum bounding rectangle, and determine the actual imprint width corresponding to the overall ink imprint contour according to the horizontal side length.

[0105] In one embodiment, in a specific ink imprint analysis system, in order to accurately measure the size of the ink imprint on the paper, the system first obtains a scanned image containing the ink imprint through a high-precision scanner. This image not only contains the detailed information of the ink imprint but also reflects the actual physical size of the paper. According to the selected paper, the actual paper length and actual paper width are determined. It should be noted that in the embodiments of the present application, the selected paper such as A4 paper or A3 paper, and the actual paper length and actual paper width can be directly determined according to the specifications of the selected paper.

[0106] Next, extract the ink imprint contour from the scanned image and calculate the minimum bounding rectangle corresponding to the overall ink imprint contour. This rectangle is the smallest rectangle surrounding the overall ink imprint contour, and its sides are parallel to the image coordinate axes.

[0107] Within the minimum bounding rectangle, the system defines the longitudinal position to be measured as the vertical line where the midpoint of the long side of the rectangle is located, and the horizontal position to be measured is the line segment where the midpoint of the short side of the rectangle is located. It should be noted that this line segment may be a horizontal line or may have a certain inclination angle. For the longitudinal position to be measured, the system calculates the length of the line segment between the two intersections of this line and the minimum circumscribed polygon to obtain the pixel imprint length along the longitudinal direction.

[0108] In one embodiment, consider the length and width of the minimum bounding rectangle of the ink imprint contour as the length and width of the imprint. The specific calculation formula is:

[0109]

[0110] It should be noted that L in the embodiments of the present application ftIndicates the actual imprint length, in centimeters (cm), L pt Indicates the actual paper length, in centimeters (cm), L fp Indicates the pixel imprint length, which is the sum of the lengths of the longitudinal pixels of the imprint, L PP Indicates the pixel paper length, which is the sum of the lengths of the longitudinal pixels of the entire paper.

[0111]

[0112] It should be noted that W in the embodiments of this application ft Indicates the actual imprint width, in centimeters (cm), W pt Indicates the actual paper width, in centimeters (cm), W fp Indicates the pixel imprint width, which is the sum of the widths of the transverse pixels of the imprint, W PP Indicates the pixel paper width, which is the sum of the widths of the transverse pixels of the entire paper.

[0113] 104. In response to the user's selection operation for the measurement point, determine the corresponding target measurement point, and calculate the imprint length at the position where the target measurement point is located based on the minimum bounding polygon.

[0114] After dragging a point in the mouse event-dragged contour, update the vertex coordinate set corresponding to the minimum bounding polygon, and redraw the closed contour connected end to end according to the vertices in the updated vertex coordinate set to achieve manual adjustment of the contour.

[0115] First, the program can automatically extract the geometric features of the imprint, such as: contact area, imprint area, length, width, and rectangular ratio. In addition, to more flexibly meet the measurement needs of the staff, this application adds manual selection of measurement points and automatically calculates the imprint position and length of the measurement point to supplement the calculation of the imprint length of the measurement point. Locate the selected measurement point through the mouse event, calculate the distance from the measurement point to the left contour, draw a line segment parallel to the center length line and obtain its intersection points with the upper and lower contours, and then calculate the length of the line segment between the two intersection points. The selection, drawing, cancellation, and calculation of the measurement point are also carried out on the transparent layer to make the interface display more stable.

[0116] After calculating the imprint length in this application, store the imprint length in the length list, and in response to the user's re-selection operation for the measurement point, delete the corresponding imprint length in the length list in reverse order, and update the display data and image to achieve cancellation and re-selection of the measurement point. All fitting, drawing, calculation, and update in the tire ink imprint image will be displayed in the window interface of the program, and the analysis image and result text file will be saved.

[0117] Specifically, in an embodiment of this application, after fitting the minimum bounding rectangle corresponding to the entire imprint contour, it includes:

[0118] Identify the imprint contour in the minimum circumscribed rectangle, determine the coordinates corresponding to the leftmost endpoint and the rightmost endpoint of the imprint contour, and calculate the abscissa corresponding to the center position of all imprint contours according to the abscissa of the leftmost endpoint and the abscissa of the rightmost endpoint to determine the imprint length at the center position;

[0119] Based on the horizontal coordinate corresponding to the center position, determine the imprint length of the left end specified position and the imprint length of the right end specified position of all imprint contours to calculate the sum of the corresponding imprint lengths of the left and right end specified positions, and based on the sum of the imprint length of the center position and the imprint lengths of the left and right end specified positions, calculate the rectangular ratio corresponding to the entire imprint area.

[0120] In one embodiment, the rectangular ratio is calculated as the percentage of the length of the center mark to the average length of the mark at 80% of the left and right positions. The specific calculation formula is:

[0121]

[0122] It should be noted that FSF in the embodiment of the present application represents the squareness ratio, and the unit is 1, L c Indicates the length of the center mark in centimeters (cm), L 8l Indicates the length of the mark at 80% on the left side, in centimeters (cm), L 8r It indicates the length of the mark at 80% on the right side, in centimeters (cm).

[0123] The closer the rectangular ratio is to 1, the closer the shape of the footprint is to a rectangle. When FSF is less than 1, it means that the ground contact length of the crown center is less than the average ground contact length of the two shoulders, the crown is concave, and the footprint is butterfly-shaped. At this time, the tire has good cornering performance, but poor straight-line performance. When FSF is greater than 1, the footprint is elliptical. At this time, the tire has good straight-line performance and strong load-bearing capacity, but poor steering performance when turning.

[0124] like Figure 3 and Figure 4 As shown, Figure 3 is the unadjusted minimum circumscribed polygon. The present application adjusts the imprint contour according to the user's drag operation request for the imprint contour, thereby obtaining Figure 4 The adjusted minimum enclosing polygon is shown.

[0125] The above is an embodiment of the method proposed in this application. Based on the same inventive concept, this embodiment of the application also provides a tire ink mark recognition device, the structure of which is as follows: Figure 5 shown.

[0126] Figure 5The figure is a schematic internal structure diagram of an identification device for tire ink imprints provided by an embodiment of the present application. As Figure 5 shown, the device includes:

[0127] At least one processor;

[0128] And a memory communicatively connected to the at least one processor;

[0129] Wherein, the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to:

[0130] Scan the original image of the ink imprint and preprocess the scanned image of the ink imprint to obtain a preprocessed imprint image; the preprocessing includes color model parameter adjustment, median filtering processing, and binarization processing;

[0131] Fit the imprint contours corresponding to all imprint regions in the imprint image, and generate an adjusted imprint contour in response to a user's dragging operation on the imprint contour;

[0132] Take all the adjusted imprint contours as a whole, fit the minimum circumscribed polygon corresponding to the whole of the imprint contours, and automatically extract the geometric features of the imprints;

[0133] In response to a user's selection operation on a measurement point, determine the corresponding target measurement point, and calculate the length of the imprint at the position of the target measurement point based on the minimum circumscribed polygon.

[0134] An embodiment of the present application also provides a non-volatile computer storage medium storing computer-executable instructions, which when executed can:

[0135] Scan the original image of the ink imprint and preprocess the scanned image of the ink imprint to obtain a preprocessed imprint image; the preprocessing includes color model parameter adjustment, median filtering processing, and binarization processing;

[0136] Fit the imprint contours corresponding to all imprint regions in the imprint image, and generate an adjusted imprint contour in response to a user's dragging operation on the imprint contour;

[0137] Take all the adjusted imprint contours as a whole, fit the minimum circumscribed polygon corresponding to the whole of the imprint contours, and automatically extract the geometric features of the imprints;

[0138] In response to a user's selection operation on a measurement point, determine the corresponding target measurement point, and calculate the length of the imprint at the position of the target measurement point based on the minimum circumscribed polygon.

[0139] The embodiments in the present application are all described in a progressive manner. For the same or similar parts among the embodiments, reference can be made to each other, and the key points of each embodiment are the differences from other embodiments. In particular, for the device and medium embodiments, since they are basically similar to the method embodiments, the description is relatively simple, and reference can be made to the relevant parts of the method embodiments for the relevant content.

[0140] The above describes specific embodiments of the present application. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recited in the claims may be performed in a different order than in the embodiments and still achieve the desired results. Additionally, the processes depicted in the figures do not necessarily require the particular order or sequential order shown to achieve the desired result. In certain embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0141] The devices and media provided in the embodiments of the present application correspond one-to-one with the methods. Therefore, the devices and media also have beneficial technical effects similar to those of their corresponding methods. Since the beneficial technical effects of the methods have been described in detail above, the beneficial technical effects of the devices and media will not be elaborated here.

[0142] Those skilled in the art should understand that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the present application can take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present application can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0143] The present application is described with reference to the flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each flow and / or block in the flowchart and / or block diagram, and the combination of flows and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, such that the instructions executed by the processor of the computer or other programmable data processing device produce a means for implementing the specified functions in Figure 1 one process or multiple processes and / or blocks Figure 1 one block or multiple blocks.

[0144] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to operate in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means that implement the functions specified in one or more of the blocks and / or processes. Figure 1 one or more of the processes and / or blocks Figure 1 specified in the one or more of the blocks and / or processes.

[0145] These computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process, thereby providing steps for implementing the functions specified in one or more of the processes and / or blocks Figure 1 one or more of the processes and / or blocks Figure 1 specified in the one or more of the blocks and / or processes.

[0146] In a typical configuration, a computing device includes one or more processors (CPUs), an input / output interface, a network interface, and memory.

[0147] The memory may include non-permanent memory in the computer-readable medium, random access memory (RAM) and / or non-volatile memory such as read only memory (ROM) or flash memory (flash RAM). Memory is an example of a computer-readable medium.

[0148] Computer-readable media includes both permanent and non-permanent, removable and non-removable media implemented by any method or technology for storage of information such as computer-readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read only memory (ROM), electrically erasable programmable read only memory (EEPROM), flash memory or other memory technologies, compact disc read only memory (CD-ROM), digital versatile discs (DVD) or other optical storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer-readable media does not include transitory media such as modulated data signals and carrier waves.

[0149] It should also be noted that the term "comprise", "include" or any other variant thereof is intended to cover non-exclusive inclusion, such that a process, method, commodity or device comprising a series of elements not only includes those elements but also includes other elements not expressly listed, or further includes elements inherent to such process, method, commodity or device. Without further limitation, an element defined by the statement "comprising an..." does not exclude the presence of additional identical elements in the process, method, commodity or device comprising the said element.

[0150] The above are only examples of the present application and are not intended to limit the present application. For those skilled in the art, various modifications and changes can be made to the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included within the scope of the claims of the present application.

Claims

1. A method for identifying tire ink marks, characterized in that: The method comprises: Scanning the original image of the ink imprint, and preprocessing the ink imprint scanned image to obtain a preprocessed imprint image; the preprocessing includes color model parameter adjustment, median filtering and binarization; Fitting the print contours corresponding to all the print areas in the print image, and generating an adjusted print contour in response to a user's dragging operation on the print contour; Taking all the adjusted imprint contours as a whole, fitting the minimum circumscribed polygon corresponding to the entire imprint contour, and automatically extracting the imprint geometric features; In response to a user's selection operation on a measuring point, a corresponding target measuring point is determined, and based on the minimum circumscribed polygon, a length of an imprint at a position where the target measuring point is located is calculated; After generating an adjusted imprint contour in response to a user's dragging operation on the imprint contour, the method further includes: Calculate the sum of the areas of the pixels of the grounded part corresponding to all the adjusted imprint contours to obtain the pixel grounded area of ​​the enclosed area corresponding to all the adjusted imprint contours; Acquire the actual paper area of ​​the paper corresponding to the ink print scan image, as well as the pixel paper length and pixel paper width corresponding to the paper, and calculate the pixel paper area corresponding to the paper according to the pixel paper length and the pixel paper width; Determine a grounded paper area ratio between the pixel grounded area and the pixel paper area, so as to calculate an actual grounded paper area corresponding to the ink imprint according to a product between the grounded paper area ratio and the actual paper area; After taking all the adjusted imprint contours as a whole and fitting the minimum circumscribed polygon corresponding to the entire imprint contour, the method further includes: Fitting the minimum circumscribed rectangle corresponding to the entire imprint contour, and determining the imprint length and imprint width of the entire imprint contour according to the length and width of the minimum circumscribed rectangle; Acquire the actual paper length and actual paper width of the paper corresponding to the ink imprint scan image, and determine the longitudinal position to be measured in the minimum circumscribed rectangle; Determine the pixel imprint length based on the line segment length between the intersection point of the straight line corresponding to the longitudinal position to be measured and the minimum circumscribed polygon; Determine an impression-to-paper length ratio between a pixel impression length and a pixel paper length, and determine an actual impression length corresponding to the entire impression contour according to a product of the impression-to-paper length ratio and an actual paper length; Determine the horizontal side length of the minimum circumscribed rectangle, and determine the actual impression width corresponding to the entire impression outline according to the horizontal side length; Fitting the imprint contours corresponding to all the imprint areas in the imprint image, and generating an adjusted imprint contour in response to a user's dragging operation on the imprint contour, specifically includes: Generating a transparent layer having the same size as the original image of the ink print, and superimposing the transparent layer on the original image; Fitting the imprint contour on the original image, and displaying the fitted imprint contour on the transparent layer; According to a preset division rule, the minimum circumscribed polygon is longitudinally divided into a plurality of longitudinal contours to obtain a corresponding plurality of equally divided points, and the plurality of equally divided points are inserted into a vertex coordinate set corresponding to the minimum circumscribed polygon; receiving a user's drag operation request for the imprint outline, and using all points in the vertex coordinate set as identification points of the drag operation request; In response to the drag operation request, an identification point corresponding to the drag operation request is determined, and a corresponding imprint contour is adjusted according to the identification point to generate an adjusted imprint contour.

2. The method for identifying tire ink marks according to claim 1, characterized in that: The original image of the ink impression is scanned, and the scanned image of the ink impression is preprocessed to obtain a preprocessed impression image, specifically including: Acquire an original image of the ink impression, and scan the original image to obtain a corresponding ink impression scanned image; Performing color filtering on the ink print scanned image, and performing median filtering on the color filtered print image; The color-filtered and filtered impression image is binarized to obtain a preprocessed impression image.

3. The method for identifying tire ink marks according to claim 2, characterized in that: The ink print scanned image is subjected to color filtering, and the color filtered print image is subjected to median filtering, specifically comprising: Adjusting the model parameters in the color model corresponding to the ink imprint scanned image to perform color filtering on the ink imprint scanned image, and extracting the imprint image corresponding to the imprint area in the ink imprint scanned image after color filtering; Based on the filter kernel, a filter process is performed on the imprint area in the color filtered imprint image to remove image edge noise in the imprint image.

4. The method for identifying tire ink marks according to claim 1, characterized in that: After taking all the adjusted imprint contours as a whole and fitting the minimum circumscribed polygon corresponding to the entire imprint contour, the method further includes: Calculating the sum of the areas of the pixels of the print portion corresponding to the minimum circumscribed polygon to obtain the pixel print area corresponding to the entire print outline; An imprint-to-paper area ratio between the pixel imprint area and the pixel paper area is determined, so as to calculate an actual imprint area corresponding to the entire imprint contour according to a product between the imprint-to-paper area ratio and the actual paper area.

5. The method for identifying tire ink marks according to claim 1, characterized in that: After fitting the minimum circumscribed rectangle corresponding to the entire print contour, the method further includes: Identify the print contour in the minimum circumscribed rectangle, determine the coordinates corresponding to the leftmost endpoint and the rightmost endpoint of the print contour, and calculate the horizontal coordinate corresponding to the center position of all the print contours according to the horizontal coordinate of the leftmost endpoint and the horizontal coordinate of the rightmost endpoint to determine the length of the print at the center position; Based on the horizontal coordinate corresponding to the center position, the imprint length of the left end designated position and the imprint length of the right end designated position of all imprint contours are determined to calculate the sum of the corresponding imprint lengths of the left and right end designated positions, and based on the sum of the imprint length of the center position and the imprint lengths of the left and right end designated positions, the rectangular ratio corresponding to the entire imprint area is calculated.

6. A tire ink mark recognition device, characterized in that: The device comprises: at least one processor; and, a memory communicatively coupled to the at least one processor; The memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the tire ink print recognition method as described in any one of claims 1-5.

7. A non-volatile computer storage medium storing computer executable instructions, characterized in that: When the computer executable instructions are executed, a tire ink print recognition method as described in any one of claims 1 to 5 is implemented.

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