A Method and System for Assessing the Weathering Degree of Stone Cultural Relics Based on High-Resolution Photography Technology

Abstract

The application discloses a kind of stone cultural relics weathering degree evaluation method and system based on high-definition photography technology, comprising: using high-definition close-range photography technology to photograph stone cultural relics, obtain the high-definition image of the stone cultural relics;Determine the weathering characteristic color scale of stone cultural relics;Using image processing technology, the high-definition image of the stone cultural relics is processed, weathering partition evaluation is carried out, the area of different weathering grades in stone cultural relics and the area ratio of the whole cultural relics are calculated;Assess the weathering degree present situation of stone cultural relics.The method uses image analysis technology to calculate the surface color weathering degree coefficient of stone cultural relics from three aspects of original rock weathering degree, water penetration surface and pigment weathering, and uses structural similarity SSIM algorithm to quantitatively calculate the overall weathering degree coefficient of stone cultural relics, to significantly evaluate the weathering degree of stone cultural relics, not only significantly improve the evaluation efficiency, but also solve the problem of quantitative evaluation, can intuitively show the weathering degree of stone cultural relics.

Description

Technical Field

[0001] This invention relates to the field of cultural relic weathering assessment technology, and in particular to a method and system for assessing the weathering degree of stone cultural relics based on high-definition photography technology. Background Technology

[0002] Stone artifacts, as witnesses to historical civilization, carry rich historical information and artistic value, and are irreplaceable cultural heritage. However, due to erosion by the natural environment, climate change, and human interference, these artifacts face serious weathering damage. Weathering not only affects the aesthetics of artifacts but may also lead to a decline in structural stability, even threatening their integrity and safety. Therefore, effective assessment of the degree of weathering of stone artifacts is crucial for developing scientific protection and restoration plans.

[0003] Currently, the assessment of weathering in stone artifacts primarily relies on traditional detection methods, such as infrared spectroscopy, X-ray diffraction, and ultrasonic testing. While these methods can provide some weathering information, they are often complex to operate, costly, and struggle to achieve a rapid and comprehensive assessment of the degree of weathering. Furthermore, some methods may require physical contact with the artifact, posing a risk of damage. With technological advancements, high-resolution photography and image analysis techniques have begun to be applied in the field of cultural relic conservation, but most research still focuses on measuring the morphological characteristics of artifacts and has not yet been widely used for assessing the degree of weathering.

[0004] Existing technologies for assessing the weathering of stone cultural relics have significant shortcomings. First, traditional testing methods typically require specialized equipment and technicians, limiting the widespread adoption and efficiency of assessments. Second, these methods often only provide information on localized or specific aspects of weathering, lacking a comprehensive assessment of the overall weathering condition of the relic. Furthermore, the high cost and potential damage risks also limit their application in large-scale cultural relic conservation projects. Therefore, developing a low-cost, high-efficiency, non-contact method for assessing the weathering of stone cultural relics is of great significance for improving the quality and efficiency of cultural relic conservation work. Summary of the Invention

[0005] To address the aforementioned deficiencies or improvement needs of existing technologies, the present invention aims to provide a method for assessing the weathering degree of stone cultural relics based on high-definition photography technology. This method utilizes high-definition close-range photogrammetry to photograph the stone cultural relics, acquiring high-definition images. Image processing technology is then used, along with a color scale based on the weathering characteristics of the stone cultural relics, to assess the original rock weathering degree, water seepage surface, and pigment weathering, thus solving the problem of quantitative assessment. A computer program is then used to calculate the area of ​​different weathering levels within the stone cultural relics and their proportion to the total area of ​​the relics. Based on these measurements, the current weathering status of the stone cultural relics is quickly assessed, and prevention and restoration plans are determined.

[0006] According to a first aspect of the present invention, a method for assessing the weathering degree of stone cultural relics based on high-definition photography technology is provided, comprising:

[0007] S100. Use high-definition close-up photography technology to photograph the stone artifact and obtain a high-definition image of the stone artifact;

[0008] S200. Collect original rock samples near the stone artifact and determine the color scale of the weathering characteristics of the stone artifact;

[0009] S300. Using image processing technology, perform color and contrast correction on the high-definition image of the stone artifact. By analyzing the color of each pixel, evaluate the weathering zoning of the stone artifact according to the weathering characteristic color scale of the stone artifact, and calculate the area of ​​different weathering levels in the stone artifact and the proportion of the area of ​​the entire artifact.

[0010] S400. Fill the corresponding unweathered colors at different locations into the corresponding high-resolution photos, and substitute the photos before and after color filling into the SSIM algorithm to calculate the similarity between the current high-resolution photos of the stone artifacts and the unweathered high-resolution photos, and use this to assess the degree of weathering of the stone artifacts.

[0011] S500. Based on the area of ​​the different weathering levels and the current weathering status of the stone cultural relics, determine the prevention and restoration plan.

[0012] Furthermore, the color scale for weathering characteristics of the stone artifacts includes a color scale for the degree of weathering of the original rock, a color scale for the moisture content of the original rock, and a color scale for the pigments on the colored surface of the original rock.

[0013] Furthermore, the method for determining the original rock weathering degree or water content color scale includes: collecting original rock samples of different weathering grades or water contents, making them into cylindrical samples, fixing the cylindrical samples of different weathering grades or water contents onto the rock sample holders, turning on the shadowless lamp, taking pictures of the cylindrical samples with a high-definition camera, inputting the images into a computer program for image processing, extracting the color information of the samples, and establishing a color scale for the original rock weathering degree or water content of stone cultural relics.

[0014] Furthermore, the method for determining the color scale of the colored surface of the stone artifact includes: determining the pigment color under different weathering degrees based on the mineral composition of the pigment on the surface of the stone artifact, and establishing a color scale for the colored surface of the stone artifact.

[0015] Further, step S300 includes:

[0016] S301. Convert the high-definition image from the RGB color space to the CIELAB color space for color correction. The conversion formula is as follows:

[0017]

[0018] In the formula, X, Y, and Z are the color channel values ​​of a pixel in the image within the color space before conversion; L* represents brightness, ranging from 0 to 100; a* represents the color range from green to red, with positive values ​​indicating the red direction and negative values ​​indicating the green direction; b* represents the color range from blue to yellow, with positive values ​​indicating the yellow direction and negative values ​​indicating the blue direction.

[0019] S302. Extract color features from each pixel, reduce data dimensionality using dimensionality reduction techniques, train the model using a supervised learning algorithm, classify each pixel based on the trained model, and assign it to different weathering levels.

[0020] S303. Count the number of pixels in each category region and calculate the actual area based on the image resolution.

[0021] Further, step S400 includes:

[0022] S401. Evaluate the similarity in brightness between two images by comparing their average brightness at x and y:

[0023]

[0024] In the formula, l(x,y) represents the brightness similarity; μ x and μ y These are the average brightness values ​​for the x and y sides of the image, respectively; C1 is a constant used to avoid a zero denominator, and is typically taken as (K1L). 2Where K1 is a very small constant, and L is the dynamic range of the image grayscale;

[0025] S402. Evaluate the similarity in contrast between two images by comparing the standard deviations of their x and y values:

[0026]

[0027] In the formula, c(x,y) represents the contrast similarity; σ x and σ y These are the standard deviations of the x and y values ​​of the image, respectively; C1 is a constant, typically taking the value (K2L). 2 Where K1 is a very small constant (e.g., 0.03), and L is the dynamic range of the image grayscale.

[0028] S403. Evaluate the structural similarity between two images by comparing their cross-correlation coefficients (x and y): The method for measuring structural similarity is as follows:

[0029]

[0030] In the formula, s(x,y) represents structural similarity; σ xy This represents the covariance of the images x and y.

[0031] Further, step S400 includes: combining the similarity of the three dimensions into an overall similarity index according to the SSIM algorithm:

[0032] SSIM(x,y)=[l(x,y)]α·[c(x,y)] β ·[s(x,y)]γ

[0033] In the formula, SSIM(x, y) represents the overall similarity; α, β, and γ are parameters used to adjust the correlation between the three factors.

[0034] According to a second aspect of the present invention, a system for assessing the weathering degree of stone cultural relics based on high-definition photogrammetry is provided, implemented by applying any step of the above-described method for assessing the weathering degree of stone cultural relics based on high-definition photogrammetry, including:

[0035] The first module is used to photograph stone artifacts using high-definition close-up photography technology to obtain high-definition images of the stone artifacts.

[0036] The second module is used to collect original rock samples near the stone artifacts and determine the color scale of the weathering characteristics of the stone artifacts.

[0037] The third module is used to perform color and contrast correction on the high-definition image of the stone artifact using image processing technology. By analyzing the color of each pixel, the weathering zoning assessment of the stone artifact is performed according to the weathering characteristic color scale of the stone artifact, and the area of ​​different weathering levels in the stone artifact and the proportion of the area of ​​the entire artifact are calculated.

[0038] The fourth module is used to fill the corresponding high-resolution photos with the unweathered colors at different locations, and to substitute the photos before and after color filling into the Structural Similarity (SSIM) algorithm to calculate the similarity between the current high-resolution photos of the stone artifacts and the unweathered high-resolution photos, and to evaluate the degree of weathering of the stone artifacts.

[0039] The fifth module is used to determine prevention and restoration plans based on the area of ​​the different weathering levels and the current weathering status of the stone cultural relics.

[0040] According to a third aspect of the present invention, a device for determining the color scale of weathering characteristics of stone cultural relics is provided, which is applied to any step of the above-mentioned method for assessing the degree of weathering of stone cultural relics based on high-definition photography technology, including:

[0041] The base includes a standard color strip on one side of the base and a rock sample holder on the other side, wherein the original rock sample is fixed on the rock sample holder;

[0042] A high-definition camera unit is mounted above the base, fixed on a tripod, with its lens pointing downwards at the original rock sample to capture high-resolution images of the sample; and

[0043] A shadowless lamp located on one side of the high-definition camera unit is used to provide uniform and shadowless illumination to ensure the accuracy of image colors.

[0044] The beneficial effects of this invention are:

[0045] 1. This invention provides a method for assessing the weathering degree of stone cultural relics based on high-definition photography technology. The method utilizes high-definition close-range photogrammetry to photograph the stone cultural relics, acquiring high-definition images. Image processing technology is then used to assess the weathering degree of the stone cultural relics in three aspects: the degree of original rock weathering, the water seepage surface, and pigment weathering, based on a color scale representing the weathering characteristics of the stone cultural relics. A computer program then calculates the area of ​​different weathering levels within the stone cultural relics and their proportion to the total area of ​​the relics. Based on these measurements, the current weathering status of the stone cultural relics is quickly assessed, and prevention and restoration plans are determined. This method significantly improves assessment efficiency, solves the problem of quantitative assessment, and visually displays the weathering degree of the stone cultural relics, making the assessment results easily understandable even to non-professionals, thus contributing to increased public participation in cultural relic protection.

[0046] 2. The weathering characteristic color scale determination device proposed in this invention is simple and practical, and only requires components such as a high-definition camera, shadowless lamp and special rock sample fixing plate. It does not require other expensive monitoring equipment, has low cost and simple determination process.

[0047] 3. The method for assessing the weathering degree of stone cultural relics based on high-definition photography technology proposed in this invention will not damage the cultural relics. Furthermore, it uses different scales for assessment based on different rock types and environmental factors. Compared with the traditional method of using a uniform rock weathering level to assess stone cultural relics, it can more accurately reflect the current weathering status of stone cultural relics.

[0048] Additional aspects and advantages of this application will be set forth in part in the description which follows, and will become apparent from the description or may be learned by practice of this application. Attached Figure Description

[0049] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings, wherein:

[0050] Figure 1 This is a flowchart of a method for assessing the weathering degree of stone cultural relics based on high-definition photography technology in an embodiment of the present invention;

[0051] Figure 2 This is a schematic diagram of a device for determining the color scale of weathering characteristics of stone cultural relics in an embodiment of the present invention;

[0052] Figure 3 This is a schematic diagram of the base of a device for determining the color scale of weathering characteristics of stone cultural relics in an embodiment of the present invention;

[0053] In all the accompanying drawings, the same reference numerals indicate the same technical features, specifically: 1-base, 11-standard color chart, 12-rock sample holder, 13-rock sample, 2-high-definition photographic unit, 3-shadowless lamp. Detailed Implementation

[0054] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0055] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0056] Those skilled in the art will understand that, unless otherwise stated, the singular forms “a,” “an,” “the,” and “the” used herein may also include the plural forms. It should be further understood that the word “comprising” as used in the specification of this application means the presence of the stated features, integers, steps, operations, elements, and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or combinations thereof.

[0057] It will be understood by those skilled in the art that, unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains. It should also be understood that terms such as those defined in general dictionaries should be understood to have the same meaning as in the context of the prior art, and should not be interpreted in an idealized or overly formal sense unless specifically defined as in the embodiments of this application.

[0058] High-resolution close-range photogrammetry is an advanced non-contact measurement method. It utilizes high-resolution photographic equipment and advanced image processing technology to perform high-precision measurements of close-range target objects, obtaining their geometric dimensions, shape, texture, and three-dimensional spatial information. This technology involves capturing images of the target object with high-precision photographic equipment, then using image processing technology to extract geometric information from the images, ultimately achieving accurate measurement of the target object. Compared to traditional contact measurement methods, high-resolution close-range photogrammetry has advantages such as being non-contact, highly efficient, and highly accurate. Currently, in the field of cultural relic restoration, high-resolution photogrammetry is mainly used to measure the geometric dimensions and morphological characteristics of cultural relics, but it has not yet been applied to assessing the degree of weathering of stone cultural relics.

[0059] Stone artifacts are subject to numerous weathering processes, resulting in significant changes to their physical and mechanical properties and material composition. These changes ultimately manifest in the artifacts' appearance, particularly their color. These factors include the degree of weathering of the rock mass itself, its moisture content, discontinuities, and the weathering of the artifact's coloring layer. Furthermore, it is necessary to eliminate the influence of environmental factors such as light intensity on color variations. Therefore, it is essential to establish color scales for different weathering conditions and degrees. By comparing these scales, the weathering status of the stone artifacts can be determined, the current weathering condition can be assessed, and weathering traces can be tracked and monitored, providing a basis for further protection and restoration of stone artifacts.

[0060] This invention provides a method for assessing the weathering degree of stone cultural relics based on high-definition photography technology. The method utilizes high-definition close-range photogrammetry to photograph the stone cultural relics, acquiring high-definition images. Image processing technology is then used, and the weathering characteristics of the stone cultural relics are assessed based on three aspects: the degree of original rock weathering, the water seepage surface, and pigment weathering. This solves the problem of quantitative assessment. A computer program is then used to calculate the area of ​​different weathering levels within the stone cultural relic and their proportion to the total area of ​​the relic. Based on these measurements, the current weathering status of the stone cultural relic can be quickly assessed, and prevention and restoration plans can be determined.

[0061] Example 1:

[0062] like Figure 1 As shown, this embodiment of the invention provides a method for assessing the weathering degree of stone cultural relics based on high-definition photography technology, including:

[0063] S100. High-definition close-up photography technology is used to photograph the stone artifact to obtain a high-definition image of the stone artifact; the high-definition image of the stone artifact also includes a standard color chart.

[0064] S200. Collect original rock samples near the stone artifact and determine the color scale of the weathering characteristics of the stone artifact; the color scale of the weathering characteristics of the stone artifact includes a color scale of the degree of weathering of the original rock, a color scale of the moisture content of the original rock, and a color scale of the pigment on the coloring surface of the original rock.

[0065] Specifically, the methods for determining the color scale of the weathering degree of the original rock of stone cultural relics include:

[0066] Samples of original rock with different weathering levels were collected from the vicinity of the stone artifacts and prepared into cylindrical samples with a height of 5mm and a diameter of 20mm indoors. The cylindrical rock samples of different weathering levels (unweathered, slightly weathered, moderately weathered, strongly weathered, and completely weathered) were fixed onto sample holders on a base. A shadowless lamp was turned on, and high-definition cameras were used to take pictures. The obtained images were input into a computer program for processing, resulting in a color scale for the weathering degree of the original rock of the stone artifacts, as shown in Table 1 (different degrees of weathering on the original rock surface result in different color characteristics; the original rock sample used in this embodiment is red sandstone):

[0067] Table 1

[0068]

[0069] The method for determining the color scale of the original rock moisture content of stone cultural relics includes: collecting original rock samples near the stone cultural relics and preparing cylindrical samples with a height of 5mm and a diameter of 20mm indoors. Rock samples with different moisture contents (taking red sandstone as an example, divided into: 0.5%, 1.0%, 1.5%, 2.0%, 2.5%) are fixed to the rock sample holder above the base. A shadowless lamp is turned on, and a high-definition camera is used to take pictures. The obtained images are input into a computer program for processing, resulting in the color scale of the original rock moisture content of the stone cultural relics, as shown in Table 2 (different moisture contents on the surface of the original rock result in different color characteristics; the original rock sample used in this embodiment is red sandstone).

[0070] Table 2

[0071]

[0072] The method for determining the color scale of the colored surface of stone cultural relics includes: determining the pigment color under different weathering degrees based on the mineral composition of the pigment on the surface of the stone cultural relics, and obtaining the color scale of the colored surface of the stone cultural relics as shown in Table 3 (different weathering degrees of the pigment on the original rock surface result in different color characteristics; in this embodiment, the pigment used on the original rock surface is a red iron-containing pigment):

[0073] Table 3

[0074]

[0075] S300. Using image processing technology, perform color and contrast correction on the high-definition image of the stone artifact. By analyzing the color of each pixel, evaluate the weathering zoning of the stone artifact according to the weathering characteristic color scale of the stone artifact, and calculate the area of ​​different weathering levels in the stone artifact and the proportion of the area of ​​the entire artifact.

[0076] Specifically:

[0077] S301. Convert the high-definition image from the RGB color space to the CIELAB color space for color correction. The conversion formula is as follows:

[0078]

[0079] In the formula, X, Y, and Z are the color channel values ​​of a pixel in the image within the color space before conversion; L* represents brightness, ranging from 0 to 100; a* represents the color range from green to red, with positive values ​​indicating the red direction and negative values ​​indicating the green direction; b* represents the color range from blue to yellow, with positive values ​​indicating the yellow direction and negative values ​​indicating the blue direction.

[0080] S302. Extract color features from each pixel, reduce data dimensionality using dimensionality reduction techniques, train the model using a supervised learning algorithm, classify each pixel based on the trained model, and assign it to different weathering levels.

[0081] S303. Count the number of pixels in each category region and calculate the actual area based on the image resolution.

[0082] S400. Fill the corresponding unweathered colors at different locations into the corresponding high-resolution photos, and substitute the photos before and after color filling into the SSIM algorithm to calculate the similarity between the current high-resolution photos of the stone artifacts and the unweathered high-resolution photos, and use this to assess the degree of weathering of the stone artifacts.

[0083] Specifically: S401, assess the similarity in brightness between two images by comparing their average brightness in the x and y regions.

[0084]

[0085] In the formula, l(x,y) represents the brightness similarity; μ x and μ y These are the average brightness values ​​for the x and y sides of the image, respectively; C1 is a constant used to avoid a zero denominator, and is typically taken as (K1L). 2 Where K1 is a very small constant (e.g., 0.01), and L is the dynamic range of the image grayscale;

[0086] S402. Evaluate the similarity in contrast between two images by comparing the standard deviations of their x and y values:

[0087]

[0088] In the formula, c(x,y) represents the contrast similarity; σ x and σ y These are the standard deviations of the x and y values ​​of the image, respectively; C1 is a constant, typically taking the value (K2L). 2Where K1 is a very small constant (e.g., 0.03), and L is the dynamic range of the image grayscale.

[0089] S403. Evaluate the structural similarity between two images by comparing their cross-correlation coefficients (x and y): The method for measuring structural similarity is as follows:

[0090]

[0091] In the formula, s(x,y) represents structural similarity; σ xy This represents the covariance of the images x and y.

[0092] S500. Based on the area of ​​the different weathering levels and the current weathering status of the stone cultural relics, assess the current weathering status of the stone cultural relics and determine prevention and restoration plans.

[0093] In summary, the method for assessing the weathering degree of stone cultural relics based on high-definition photography technology provided by this invention utilizes high-definition close-range photogrammetry to photograph stone cultural relics, acquiring high-definition images of the relics. Image processing technology is then used to assess the weathering degree of the original rock, the water seepage surface, and pigment weathering based on a color scale representing the weathering characteristics of the stone cultural relics. Finally, a computer program calculates the area of ​​different weathering levels within the stone cultural relics and their proportion to the total area of ​​the relics. Based on these measurements, the current weathering status of the stone cultural relics can be quickly assessed, and prevention and restoration plans can be determined. This method effectively solves the problem of quantitative assessment of cultural relics, visually displaying the weathering degree of stone cultural relics, making the assessment results easily understandable even to non-professionals. This helps to increase public participation in cultural relic protection. Furthermore, this method does not damage the relics and can use different scales for assessment based on different lithologies and environmental factors. Compared to traditional methods that use a uniform rock weathering level to assess stone cultural relics, this method more accurately reflects the current weathering status of the relics.

[0094] Example 2:

[0095] like Figure 2 Figure 3As shown, this embodiment of the invention provides a device for determining the color scale of weathering characteristics of stone cultural relics, comprising: a base 1, including a standard color strip 11 on one side of the base 1 and a rock sample holder 12 on the other side, wherein a raw rock sample 13 is fixed on the rock sample holder 12; a high-definition camera unit 2 located above the base 1, the high-definition camera unit 2 being fixed with a tripod, the lens being aimed downwards at the raw rock sample 13 for capturing high-resolution images of the raw rock sample 13; and a shadowless lamp 3 located on one side of the high-definition camera unit 2 for providing uniform and shadowless illumination to ensure the accuracy of image colors; the design of the device for determining the color scale of weathering characteristics of stone cultural relics provided in this embodiment takes into account the ease of operation for users. Through the modular design of the high-definition camera unit, shadowless lamp, sample fixing device, etc., the entire evaluation process is simple and easy to perform, requiring no complex equipment operation skills, and is convenient for cultural relic conservation workers with different backgrounds to use.

[0096] The method for determining the color scale of the weathering degree of the original rock using the above-mentioned device includes: collecting original rock samples 13 of different weathering grades, fixing the original rock samples 13 of different weathering grades on the rock sample holder 12 respectively, turning on the shadowless lamp 3, taking pictures of the original rock samples 13 using the high-definition photography unit 2, obtaining high-resolution images of the original rock samples 13 and inputting them into a computer program for image processing, extracting color information and establishing a color scale of the weathering degree of the original rock of the stone cultural relics; the method for determining the color scale of the moisture content of the original rock using the above-mentioned device includes: collecting original rock samples 13 of different moisture contents, fixing the original rock samples 13 of different moisture contents on the rock sample holder 12 respectively, turning on the shadowless lamp 3, taking pictures of the original rock samples 13 using the high-definition photography unit 2, obtaining high-resolution images of the original rock samples 13 and inputting them into a computer program for image processing, extracting color information and establishing a color scale of the moisture content of the original rock of the stone cultural relics.

[0097] It should be understood that although the steps in the flowcharts of the accompanying figures are shown sequentially as indicated by the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the accompanying figures may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily completed at the same time, but can be executed at different times, and their execution order is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the sub-steps or stages of other steps.

[0098] The above description is only a partial embodiment of this application. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of this application, and these improvements and modifications should also be considered within the scope of protection of this application.

Claims

1. A method for evaluating the weathering degree of stone cultural relics based on high-definition photography technology, characterized in that, The method comprises the following steps: S100, using high-definition close-range photography technology to shoot the stone cultural relics, and obtaining high-definition images of the stone cultural relics; S200, collecting original rock samples near the stone cultural relics, and determining a stone cultural relic weathering characteristic color scale; S300, using image processing technology to correct the color and contrast of the high-definition images of the stone cultural relics, analyzing the color of each pixel point, and evaluating the weathering zoning of the stone cultural relics according to the stone cultural relic weathering characteristic color scale, and calculating the area of different weathering grades of the stone cultural relics and the area ratio of the stone cultural relics; S400, filling the unweathered color corresponding to different positions into the corresponding high-definition photos, and inputting the photos before and after the color filling into a structural similarity (SSIM) algorithm, calculating the similarity between the current high-definition photos of the stone cultural relics and the unweathered high-definition photos, and taking the similarity as the weathering degree of the stone cultural relics; S500, determining a prevention and repair scheme according to the area of different weathering grades and the weathering degree of the stone cultural relics.

2. The method for evaluating the weathering degree of stone cultural relics based on high-definition photography technology according to claim 1, characterized in that, The stone cultural relic weathering characteristic color scale comprises an original rock weathering degree color scale, an original rock water content color scale, and an original rock colored surface pigment color scale. 3.The method of evaluating the weathering degree of stone cultural relics based on high-definition photography technology according to claim 2, characterized in that, The method for determining the original rock weathering degree or water content color scale comprises the following steps: collecting original rock samples of different weathering grades or water contents, preparing cylindrical samples, fixing the cylindrical samples of different weathering grades or water contents on rock sample sockets respectively, turning on a shadowless lamp, shooting the cylindrical samples by using a high-definition camera, inputting a computer program for image processing, extracting color information of the samples, and establishing the original rock weathering degree or water content color scale of the stone cultural relics.

4. The method for evaluating the weathering degree of stone cultural relics based on high-definition photography technology according to claim 2, characterized in that, The method for determining the original rock colored surface pigment color scale comprises the following steps: determining the color of pigments under different weathering degrees according to the mineral composition of the surface pigments of the stone cultural relics, and establishing the original rock colored surface pigment color scale.

5. The method for evaluating the weathering degree of stone cultural relics based on high-definition photogrammetry technology according to claim 2, characterized in that, Different sample colors in the stone cultural relic weathering characteristic color scale have corresponding RGB values and weathering characteristic values.

6. The method for evaluating the weathering degree of stone cultural relics based on high-definition photography technology according to any one of claims 1-5, characterized in that, The step S300 comprises the following steps: S301, converting the high-definition images from an RGB color space to a CIELAB color space for color correction, and the conversion formula is as follows: In the formula, X, Y and Z are the numerical values of the color channel values of a certain pixel point in the image in the color space before conversion, and X, Y and Z directly correspond to R, G and B channel values respectively; L* represents the brightness, ranging from 0 to 100; a* represents the color range from green to red, and the positive value represents the red direction and the negative value represents the green direction; b* represents the color range from blue to yellow, and the positive value represents the yellow direction and the negative value represents the blue direction; S302, extracting the color features from each pixel point, reducing the data dimension by using a dimension reduction technology, and training by using a supervised learning algorithm, classifying each pixel point based on the trained model, and assigning the pixel point to different weathering grades; S303, counting the number of pixels in each classification area, and calculating the actual area according to the image resolution.

7. A system for evaluating the weathering degree of stone cultural relics based on high-definition photogrammetry technology, characterized in that, The stone cultural relic weathering degree evaluation method based on high-definition photography technology is realized by using the method according to any one of claims 1-6. The first module is used for shooting the stone cultural relics by using high-definition close-range photography technology to obtain high-definition images of the stone cultural relics. The second module is used for collecting original rock samples near the stone cultural relics to determine the weathering characteristic color scale of the stone cultural relics. The third module is used for correcting the color and contrast of the high-definition images of the stone cultural relics by using image processing technology, performing weathering zoning evaluation on the stone cultural relics according to the weathering characteristic color scale by analyzing the color of each pixel, and calculating the area of different weathering grades of the stone cultural relics and the area ratio of the stone cultural relics. The fourth module is used for filling the unweathered color corresponding to different positions into the corresponding high-definition photos, substituting the photos before and after the color filling into the structural similarity (SSIM) algorithm, calculating the similarity between the current high-definition photos of the stone cultural relics and the unweathered high-definition photos, and evaluating the weathering degree of the stone cultural relics. The fifth module is used for determining the prevention and repair scheme according to the area of different weathering grades and the weathering degree of the stone cultural relics.

8. A device for determining a weathering feature color scale of a stone cultural relic, applied to the method for evaluating the weathering degree of a stone cultural relic based on high-definition photography technology according to any one of claims 1-6, characterized in that, It comprises: a base (1) comprising a standard color band (11) on one side of the base (1) and a rock sample bayonet (12) on the other side, wherein the rock sample bayonet (12) is fixed with an original rock sample (13); a high-definition camera unit (2) arranged above the base (1), wherein the high-definition camera unit (2) is fixed by a tripod, the lens is downwardly aligned with the original rock sample (13), and the high-definition camera unit (2) is used for capturing high-resolution images of the original rock sample (13); and a shadowless lamp (3) arranged on one side of the high-definition camera unit (2), which is used for providing uniform and shadowless illumination to ensure the accuracy of the image color. ​

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