CN115908411A - Concrete curing quality analysis method based on visual detection - Google Patents

Concrete curing quality analysis method based on visual detection Download PDF

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CN115908411A
CN115908411A CN202310014998.XA CN202310014998A CN115908411A CN 115908411 A CN115908411 A CN 115908411A CN 202310014998 A CN202310014998 A CN 202310014998A CN 115908411 A CN115908411 A CN 115908411A
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edge line
edge
crack
line
lines
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CN115908411B (en
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刘国帅
岳远志
李明川
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Shandong Water Conservancy Construction Group Co ltd
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Abstract

The invention discloses a concrete curing quality analysis method based on visual inspection, which relates to the field of image processing and comprises the following steps: acquiring an edge line in a gray level image of the surface of the concrete to be detected; obtaining the crack possibility of each edge line according to the gray average value and the bending degree of each edge line; obtaining a first edge line and a second edge line by utilizing crack possibility; acquiring a target edge line and a target end point of each first edge line; recalculating the crack probability for the extended first edge line; determining the crack edge lines according to the crack possibility of the first edge lines and the extended first edge lines and the number of the second edge lines in the minimum circumscribed rectangle, and evaluating the curing quality of the concrete according to the area ratio of the crack edge lines in the gray level image. The method improves the accuracy of crack defect detection, and further ensures that the obtained concrete curing quality evaluation result is more accurate.

Description

Concrete curing quality analysis method based on visual detection
Technical Field
The invention relates to the technical field of image processing, in particular to a concrete curing quality analysis method based on visual inspection.
Background
The concrete curing method is a sub-project which consumes the longest time and has the greatest influence on the quality of concrete in the whole concrete project. The concrete curing is generally performed by watering natural curing, spraying film curing and plastic film wrapping curing to keep the concrete moist and avoid water loss so as to achieve the curing purpose. However, many projects are too careless to maintain, so that the final concrete hydration effect is not good, cracks appear, and the service life of the project can be seriously influenced. Therefore, maintenance quality inspection is required to be continuously carried out in the concrete maintenance process and immediately after the maintenance is finished, and whether cracks appear is mainly detected.
In the prior art, the crack defect is usually obtained by edge detection, but the concrete surface also has a groove mark with a shape similar to the crack defect, the crack is generated due to the damage of the concrete quality and performance, and the groove mark is surface change caused by misoperation and has little influence on the quality; therefore, only a crack region with defects needs to be obtained, but the groove mark and the crack defect are in a slender curve form in a gray image, so that the groove mark and the crack defect on the surface of the concrete are similar to edge lines of the crack defect during edge detection, are difficult to distinguish, and the accurate crack defect cannot be obtained, so that the maintenance quality of the concrete cannot be accurately analyzed.
Disclosure of Invention
The invention provides a concrete curing quality analysis method based on visual inspection, which aims to solve the problem that the defects of groove marks and cracks on the surface of concrete are difficult to distinguish in the existing edge inspection process.
The concrete curing quality analysis method based on visual inspection adopts the following technical scheme:
acquiring a gray image of the surface of the concrete to be detected;
acquiring edge lines in the gray level image and non-edge pixel points in the middle of double thresholds during edge detection as candidate pixel points;
obtaining the curvature of each edge line according to the number of the pixel points on each edge line and the coordinates of the pixel points; obtaining the crack possibility of each edge line according to the gray average value and the bending degree of each edge line;
dividing the edge line into a first edge line and a second edge line according to the crack possibility, wherein the crack possibility of the first edge line is greater than that of the second edge line;
obtaining a target edge line with the shortest distance between each first edge line by using the distance between the end point of each first edge line and the end points of other first edge lines, and taking the end point with the shortest distance between each first edge line and the target edge line as a target end point;
determining whether the first edge line is extended or not according to whether candidate pixel points exist in the target end point neighborhood of each first edge line and the distance between the candidate pixel points when the candidate pixel points exist and the end points of the corresponding target edge lines, and recalculating the crack possibility of the extended first edge line;
and marking the first edge lines which are not extended and the first edge lines which are extended as third edge lines, determining crack edge lines according to the number of second edge lines in the minimum circumscribed rectangle of each third edge line and the crack possibility of the third edge lines, and evaluating the maintenance quality of the concrete according to the area occupation ratio of the crack edge lines in the gray level image.
Further, the step of obtaining the curvature of each edge line includes:
obtaining the absolute value of the slope of the connecting line of the starting point and the end point of each edge line according to the coordinates of the starting point and the end point of the pixel point on each edge line in the gray level image, and using the absolute value as a reference slope;
obtaining the slope absolute value of the connecting line of each pixel point and the starting point according to the coordinates of each pixel point and the starting point on each edge line;
and calculating the average value of the absolute value of the difference value between the slope absolute value of each pixel point on each edge line and the starting point connecting line and the reference slope, and normalizing the obtained average value to obtain the curvature of each edge line.
Further, the step of determining whether to extend the first edge line includes:
taking a target endpoint of the first edge line as a seed point, and if no candidate pixel point exists in the neighborhood of the seed point, not extending the first edge line;
if candidate pixel points exist in the neighborhood of the seed point, acquiring the candidate pixel point with the maximum gradient in the neighborhood as a target candidate point;
and if the minimum distance between the target candidate point and the corresponding target edge line end point is not less than the distance between the target end point and the target edge line end point, not extending the first edge line, if the minimum distance is less than the distance, extending the first edge line to the target candidate pixel point, and continuously taking the target candidate pixel point as a new seed point to determine whether to extend the first edge line.
Further, the formula for obtaining the crack probability of each edge line is as follows:
Figure 828714DEST_PATH_IMAGE001
wherein ,
Figure 830430DEST_PATH_IMAGE002
denotes the first
Figure 657572DEST_PATH_IMAGE003
The possibility of cracking of the edge lines;
Figure 333404DEST_PATH_IMAGE004
is shown as
Figure 978011DEST_PATH_IMAGE003
Curvature of a border line;
Figure 274214DEST_PATH_IMAGE005
is shown as
Figure 170626DEST_PATH_IMAGE006
Curvature of a border line;
Figure 638647DEST_PATH_IMAGE007
representing the total number of edge lines in the grayscale image;
Figure 549097DEST_PATH_IMAGE008
representing bends of all edge lines in a grayscale imageA curvature mean value;
Figure 164886DEST_PATH_IMAGE009
denotes the first
Figure 864989DEST_PATH_IMAGE006
Normalizing the gray level mean value of the edge line;
Figure 577730DEST_PATH_IMAGE010
denotes the first
Figure 672462DEST_PATH_IMAGE003
Normalizing the gray level mean value of the edge line of the strip;
Figure 576481DEST_PATH_IMAGE011
expressing the mean value of the normalized values of the gray mean values of all the edge lines in the gray image;
Figure 814696DEST_PATH_IMAGE012
is a normalization function.
Further, the step of determining the crack edge line comprises the following steps:
the formula for obtaining the final fracture possibility of each third edge line is as follows:
Figure 788468DEST_PATH_IMAGE013
wherein ,
Figure 680201DEST_PATH_IMAGE014
denotes the first
Figure 972380DEST_PATH_IMAGE003
The ultimate crack potential of the third edge line of the strip;
Figure 873339DEST_PATH_IMAGE002
is shown as
Figure 436039DEST_PATH_IMAGE003
Splitting of the third edge lineThe possibility of seams;
Figure 639618DEST_PATH_IMAGE015
is shown as
Figure 45192DEST_PATH_IMAGE003
The area of the minimum circumscribed rectangle of the third edge line;
Figure 625209DEST_PATH_IMAGE016
is shown as
Figure 901469DEST_PATH_IMAGE003
The number of second edge lines in the minimum circumscribed rectangle of the third edge line;
Figure 574153DEST_PATH_IMAGE017
is an exponential function with a natural constant e as a base;
and determining a third edge line with the final crack possibility larger than a preset crack threshold value as a crack edge line.
Further, the step of obtaining the target edge line with the closest distance to each first edge line comprises:
acquiring the minimum distance between the end point of each first edge line and the end points of other first edge lines;
selecting a minimum value from all the minimum distances obtained from each first edge line;
and taking the first edge line corresponding to the minimum value as the target edge line with the shortest distance from the first edge line.
Further, the step of evaluating the curing quality of the concrete according to the area ratio of the crack edge line in the gray level image comprises the following steps:
if the area ratio of the crack edge line in the gray level image is smaller than a preset first area threshold value, the maintenance quality of the concrete is qualified;
if the area proportion of the crack edge line in the gray-scale image is larger than or equal to the first area threshold value and smaller than the preset second area threshold value, the concrete curing quality is poor;
and if the area ratio of the crack edge line in the gray level image is greater than or equal to the second area threshold value, the maintenance quality of the concrete is unqualified.
Further, the dividing of the edge line into a first edge line and a second edge line according to the crack probability includes:
setting a crack possibility threshold value, and taking an edge line with the crack possibility larger than the crack possibility threshold value as a first edge line;
and taking the edge line with the crack possibility smaller than or equal to the crack possibility threshold value as a second edge line.
The invention has the beneficial effects that: according to the concrete curing quality analysis method based on visual detection, the crack possibility of each edge line is obtained through the curvature and the gray average value of each edge line, the edge line of the crack is more bent and has larger curvature relative to the edge line of the groove mark, the directions of the edge lines of the groove mark are consistent, and the brightness of the crack and the brightness of the groove mark in a gray image are different, namely the gray values are different, so that the crack possibility can be obtained by combining the curvature and the gray average value of the edge lines for preliminary distinction, and a first edge line closer to crack defects and a second edge line closer to the groove mark are obtained; because some tiny crack edges can not be obtained by conventional edge detection, extending the first edge line through the distance between a non-edge pixel point in a double-threshold interval and the nearest target edge line during edge detection to obtain a complete extended first edge line; and because the number of the grooves around the concrete surface crack defect is less than that around the groove, the crack edge line is further determined by combining the characteristic and the crack possibility of the first edge line, so that the crack edge line is more accurate, and the obtained quality evaluation result of the concrete surface is more accurate.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the embodiments or the prior art descriptions will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.
FIG. 1 is a flow chart illustrating the general steps of an embodiment of a visual inspection-based concrete curing quality analysis method according to the present invention;
fig. 2 is a grayscale image of a concrete surface.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
An embodiment of the method for analyzing concrete curing quality based on visual inspection of the present invention is shown in fig. 1, and the method includes:
s1, acquiring a gray image of the surface of concrete to be detected; and acquiring edge lines in the gray level image and non-edge pixel points in the middle of double thresholds during edge detection as candidate pixel points.
Specifically, an unmanned aerial vehicle provided with a professional camera is used for acquiring images of the surface of concrete in a flying manner, and the images are influenced by mechanical noise in the process of acquiring the images, so that noise points exist in the acquired images, and the acquired images are subjected to Gaussian filtering to obtain the noise-reduced images.
The image after noise reduction is grayed to obtain a grayscale image of the concrete surface, as shown in fig. 2.
And carrying out edge detection on the gray level image by using a Canny operator to obtain edge lines in the gray level image, wherein the obtained edge lines comprise edge lines of cracks and furrow marks on the surface of the concrete.
When the Canny operator carries out edge detection, double thresholds, namely an upper bound threshold and a lower bound threshold, are set, and if the gradient of the pixel point is greater than the upper bound threshold, the pixel point is regarded as a boundary inevitably and is called as a strong edge pixel point; if the pixel value is smaller than the lower bound threshold value, the pixel is regarded as a non-edge pixel point; and if the pixel points between the upper and lower bound thresholds belong to the eight neighborhoods of the strong edge pixel points, the pixel points are judged to be weak edge pixel points, and if the pixel points do not belong to the eight neighborhoods of the strong edge pixel points, the pixel points are judged to be non-edge pixel points. However, in this scheme, since the crack region has permeability, it is necessary to further analyze the pixels not belonging to the eight neighborhoods of edge pixels, and obtain non-edge pixels between the upper and lower bound thresholds as candidate pixels for subsequent analysis.
S2, obtaining the curvature of each edge line according to the number of the pixel points on each edge line and the coordinates of the pixel points.
The cracks are generated from inside to outside when the concrete is damaged, the groove marks are scratches on the surface of the concrete, the edge lines of the defects of the cracks are more bent and have larger curvature, and the edge lines of the groove marks have stronger direction consistency, so that the cracks and the groove marks can be preliminarily distinguished according to the curvature of the edge lines.
Specifically, the number of pixel points and the coordinates of the pixel points on each edge line in the gray-scale image are obtained.
Obtaining the absolute value of the slope of the connecting line of the starting point and the end point of each edge line as a reference slope according to the coordinates of the starting point and the end point of the pixel point on each edge line; obtaining the slope absolute value of the connecting line of each pixel point and the starting point according to the coordinates of each pixel point and the starting point on each edge line; and calculating the average value of the absolute value of the difference value between the slope absolute value of each pixel point on each edge line and the starting point connecting line and the reference slope, and normalizing the obtained average value to obtain the curvature of each edge line. The formula for specifically calculating the curvature of each edge line is as follows:
Figure 76809DEST_PATH_IMAGE018
wherein ,
Figure 319572DEST_PATH_IMAGE004
denotes the first
Figure 591284DEST_PATH_IMAGE003
Curvature of a border line;
Figure 261300DEST_PATH_IMAGE019
denotes the first
Figure 251253DEST_PATH_IMAGE003
The number of pixel points on the edge line;
Figure 32127DEST_PATH_IMAGE020
is as follows
Figure 922460DEST_PATH_IMAGE003
The coordinates of the start point of the edge line,
Figure 904323DEST_PATH_IMAGE021
is as follows
Figure 506205DEST_PATH_IMAGE003
The coordinates of the end point of the edge line,
Figure 966137DEST_PATH_IMAGE022
is as follows
Figure 337075DEST_PATH_IMAGE003
On the strip edge line
Figure 489839DEST_PATH_IMAGE006
The coordinates of each pixel point, the starting point and the end point of the edge line are any end points of the edge line;
Figure 313438DEST_PATH_IMAGE012
is a normalization function;
Figure 72666DEST_PATH_IMAGE023
is shown as
Figure 298111DEST_PATH_IMAGE003
Absolute value of slope of connection line between start point and end point of edge line, and slope of connection line between start point and end pointThe absolute value is used as a reference slope; second pixel from edge line
Figure 356197DEST_PATH_IMAGE024
Starting to traverse (the first pixel point is the starting point), respectively calculating the first
Figure 932672DEST_PATH_IMAGE006
A pixel
Figure 734406DEST_PATH_IMAGE022
And a starting point
Figure 548778DEST_PATH_IMAGE020
And calculating the mean value of the absolute values of all the difference values and normalizing to obtain the curvature of the edge line. The absolute value of the slope obtained by each pixel point is compared with the reference slope, because the starting point and the end point on the edge line are connected to determine a reference direction, if the edge line is a straight line, the difference between the direction of any one pixel point on the edge line and the connecting line of the starting point and the reference direction is not large, and if the difference is larger, the edge line is considered to deviate from the straight line more, namely the curvature is larger. The difference results are normalized to facilitate calculation of crack probabilities for the gray values of subsequent bond edge lines.
S3, obtaining the crack possibility of each edge line according to the gray average value and the bending degree of each edge line; the edge lines are divided into first edge lines and second edge lines according to crack probability, and the crack probability of the first edge lines is greater than that of the second edge lines.
The bending degree of the edge line of the crack is large, but the edge of a local section of the crack is not obvious, so that a continuous crack edge line is divided into a plurality of sections of edge lines during edge detection, and the bending degree of each local section of the edge line is not high, so that the edge line can be detected as a groove mark. Therefore, it is necessary to distinguish the crack from the groove in gray scale, the gray scale of the groove in the gray scale image is brighter than the gray scale of the crack, and if the gray scale of the pixel in the gray scale image is divided into three levels, i.e., low, medium and high, the crack mainly appears in two levels, and the groove mainly appears in two levels, i.e., medium and high, so that the possibility that the edge line is the crack edge line is further determined by combining the gray scale value and the curvature.
Specifically, the gray value of each pixel point on each edge line is obtained, and the gray regularity of each edge line is calculated according to the following formula:
Figure 308924DEST_PATH_IMAGE025
wherein ,
Figure 107115DEST_PATH_IMAGE010
denotes the first
Figure 211075DEST_PATH_IMAGE003
The gray scale regularity of the edge lines;
Figure 145533DEST_PATH_IMAGE019
is shown as
Figure 811001DEST_PATH_IMAGE003
The number of pixel points on the edge line;
Figure 96489DEST_PATH_IMAGE026
is shown as
Figure 240025DEST_PATH_IMAGE003
On the strip edge line
Figure 874662DEST_PATH_IMAGE027
The gray value of each pixel point;
Figure 101244DEST_PATH_IMAGE028
is shown as
Figure 952657DEST_PATH_IMAGE003
The gray average value of the pixel points on the edge line;
Figure 883573DEST_PATH_IMAGE012
is a normalization function; the gray scale rule of the edge line is represented by the gray scale average value of the pixel points on each edge line, the larger the gray scale average value is, the brighter the gray scale in the gray scale image is, the more likely the gray scale is to be a groove mark edge line, the smaller the gray scale average value is, the more likely the gray scale is to be a crack edge line, and the normalization of the gray scale average value is to facilitate the calculation of the crack possibility in the follow-up process by combining the curvature of the edge line.
The crack probability of each edge line is calculated according to the following formula:
Figure 58202DEST_PATH_IMAGE001
wherein ,
Figure 295498DEST_PATH_IMAGE002
is shown as
Figure 555579DEST_PATH_IMAGE003
The possibility of cracking of the edge lines;
Figure 40918DEST_PATH_IMAGE004
is shown as
Figure 70054DEST_PATH_IMAGE003
Curvature of a border line;
Figure 248225DEST_PATH_IMAGE005
is shown as
Figure 730022DEST_PATH_IMAGE006
Curvature of a border line;
Figure 284631DEST_PATH_IMAGE007
representing the total number of edge lines in the grayscale image;
Figure 168274DEST_PATH_IMAGE008
representing the curvature mean value of all edge lines in the gray level image;
Figure 15882DEST_PATH_IMAGE009
denotes the first
Figure 329182DEST_PATH_IMAGE006
Normalization of the mean value of the gray levels of the edge lines, i.e. second
Figure 687483DEST_PATH_IMAGE006
The gray scale regularity of the edge lines;
Figure 691211DEST_PATH_IMAGE010
is shown as
Figure 712650DEST_PATH_IMAGE003
Normalization of the mean value of the gray levels of the edge lines, i.e. second
Figure 44405DEST_PATH_IMAGE003
The gray scale regularity of the edge lines;
Figure 799871DEST_PATH_IMAGE011
expressing the mean value of the normalized values of the gray mean values of all the edge lines in the gray image, namely the gray regularity mean value of all the edge lines;
Figure 533472DEST_PATH_IMAGE012
is a normalization function.
Figure 348981DEST_PATH_IMAGE029
The degree of curvature and the gray scale regularity are related to each other negatively, so that the obtained related coefficient is a negative number, and in order to conveniently represent the related degree, the absolute value of the related coefficient is taken, and the larger the absolute value is, the larger the negative related degree of the degree of curvature and the gray scale regularity is; the ratio of the two is weighted by the degree of negative correlation of the two, and the greater the curvature, the smaller the grayscale value, and the greater the degree of negative correlation of the two, the greater the probability that the edge line is considered to be a crack edge line. And normalizing the obtained result, so that a threshold value can be conveniently set to distinguish edge lines.
Setting a crack possibility threshold, wherein an edge line with the crack possibility greater than the crack possibility threshold is used as a first edge line, and an edge line with the crack possibility less than or equal to the crack possibility threshold is used as a second edge line, and the crack possibility threshold is set to be 0.45 in the embodiment of the invention. The first edge line is more likely to be a crack edge line and the second edge line is more likely to be a score edge line.
And S4, obtaining a target edge line with the shortest distance of each first edge line by using the distance between the end point of each first edge line and the end points of other first edge lines, and taking the end point with the shortest distance of each first edge line and the target edge line as a target end point.
The cracks have strong permeability, and the Canny edge detection cannot obtain some fine cracks, only analyzes the detected edge lines, and does not consider the undetected fine cracks, so that the obtained detection result is not accurate enough, and further analysis can be performed through pixel points around the first edge line which is closer to the crack edge line.
Specifically, because the crack has strong permeability, the probability that a fine crack exists between two first edge lines which are closest to each other is high, the minimum distance between the end point of each first edge line and the end points of other first edge lines is obtained, each edge line has two end points, when the distance between the two first edge lines is calculated, one end point is selected from the two edge lines to be matched for distance calculation, four calculation results are obtained in total, and the minimum value of the four calculation results is selected as the minimum distance between the two first edge lines; selecting a minimum value from all the minimum distances obtained from each first edge line; and taking other first edge lines corresponding to the selected minimum value as the nearest target edge line of the first edge line.
And taking the end point of each first edge line, which is closest to the end point of the target edge line, as a target end point.
S5, determining whether to extend the first edge line or not according to whether a candidate pixel point exists in the target end point neighborhood of each first edge line and the distance between the candidate pixel point when the candidate pixel point exists and the end point of the corresponding target edge line, and recalculating the crack possibility of the extended first edge line.
When the Canny operator carries out edge detection, partial non-edge pixel points between upper and lower bound thresholds exist, and the partial non-edge pixel points which are not judged as weak edges are taken as candidate pixel points for further analysis in consideration of the permeability of cracks.
Specifically, the target end point of the first edge line is used as a seed point, candidate pixel points are searched in 5 × 5 neighborhoods of the seed point (the size of the neighborhood can be adjusted according to specific implementation conditions), if no candidate pixel point exists in the neighborhoods of the seed point, it is indicated that no fine crack exists between the two first edge lines, and the first edge lines are not extended; if candidate pixel points exist in the neighborhood of the seed point, acquiring the candidate pixel point with the maximum gradient in the neighborhood as a target candidate point; and if the minimum distance between the target candidate point and the corresponding target edge line end point is not less than the distance between the target end point and the target edge line end point, indicating that no fine crack exists between the two first edge lines, not extending the first edge lines, and if the minimum distance is less than the distance, extending the first edge lines to the target candidate pixel points.
And continuing to use the target candidate pixel point as a new seed point to determine whether to extend the first edge line until no candidate pixel point exists in the neighborhood of the new seed point or the minimum distance between the target candidate pixel point and the corresponding target edge line end point is not less than the distance between the target end point and the target edge line end point, and stopping extension to obtain the complete first edge line after extension.
The crack probability is recalculated for all extended first edge lines according to steps S2-S3.
And S6, marking the first edge lines which are not extended and the first edge lines which are extended as third edge lines, determining the crack edge lines according to the number of the second edge lines in the minimum circumscribed rectangle of each third edge line and the crack possibility of the third edge lines, and evaluating the maintenance quality of the concrete according to the area ratio of the crack edge lines in the gray level image.
Since the grooves are distributed in clusters on the concrete surface, a plurality of second edges closer to the groove edge lines are arranged around the grooves, and the second edges closer to the groove edge lines around the cracks can calculate the final crack possibility of each first edge line and the extended first edge line according to the characteristics.
Specifically, the first edge line which is not extended and the first edge line which is extended are marked as third edge lines, each third edge line is subjected to minimum circumscribed rectangles, the number of second edge lines in the minimum circumscribed rectangles of each third edge line is obtained, and the final crack possibility of each third edge line is calculated according to the following formula:
Figure 433612DEST_PATH_IMAGE013
wherein ,
Figure 461611DEST_PATH_IMAGE014
is shown as
Figure 813833DEST_PATH_IMAGE003
The ultimate crack potential of the third edge line of the strip;
Figure 800243DEST_PATH_IMAGE002
is shown as
Figure 106591DEST_PATH_IMAGE030
The likelihood of cracking of the third edge line of the strip;
Figure 203860DEST_PATH_IMAGE015
is shown as
Figure 646474DEST_PATH_IMAGE003
The area of the minimum circumscribed rectangle of the third edge line;
Figure 803785DEST_PATH_IMAGE016
is shown as
Figure 597429DEST_PATH_IMAGE003
The number of second edge lines in the minimum bounding rectangle of the third edge line;
Figure 232810DEST_PATH_IMAGE017
is an exponential function with a natural constant e as a base;
Figure 291115DEST_PATH_IMAGE031
representing the number of second edge lines per unit area in the minimum bounding rectangle, the greater the number of second edges per unit area, the more likely the edge line is to be a groove edge line, i.e. the
Figure 619328DEST_PATH_IMAGE031
The greater the ratio of (A) is, the greater the ratio of (B) is
Figure 634688DEST_PATH_IMAGE017
After negative correlation mapping, the final crack probability of the edge line is smaller, and the final crack probability is in the denominator
Figure 339339DEST_PATH_IMAGE002
The larger the negative correlation map, the greater the likelihood of a final crack resulting in the edge line.
Figure 756545DEST_PATH_IMAGE017
The negative correlation map is used to determine the fracture edge line from the third edge lines in order to select the fracture threshold.
In the embodiment of the invention, the crack threshold value is set to be 0.5, and the third edge line with the final crack possibility larger than the crack threshold value is determined as the crack edge line to obtain all crack edge lines in the gray level image. Meanwhile, the scheme can label the crack edge lines in the gray level image, and the gray level image with the labeled crack edge lines is displayed on the corresponding display, so that the abnormal condition of the concrete surface can be checked more visually.
The ratio of the number of the pixel points on all the crack edge lines to the total number of the pixel points in the gray level image is obtained, the larger the ratio is, the worse the quality of the concrete surface is, the worse the concrete curing quality is, and a concrete curing quality grade implementer can automatically set the threshold of the ratio according to actual conditions to obtain the ratio.
In this embodiment, if the area ratio of the crack edge line in the grayscale image is less than the preset first area threshold value of 0.3, the maintenance quality of the concrete is qualified, and only the local crack needs to be specifically processed; if the area ratio of the crack edge line in the gray level image is greater than or equal to the first area threshold value 0.3 and less than the preset second area threshold value 0.7, the maintenance quality of the concrete is poor, and the area where the crack is located needs to be repaired; and if the area ratio of the crack edge line in the gray-scale image is greater than or equal to 0.7 of the second area threshold, the curing quality of the concrete is unqualified, the crack penetrates through the whole concrete surface, and the curing quality is poor.
In summary, the invention provides a concrete curing quality analysis method based on visual detection, the crack possibility of each edge line is obtained through the curvature and the gray average of each edge line, because the edge line of the crack is more tortuous and has larger curvature relative to the groove edge line, the directions of the groove edge lines are consistent, and the brightness of the crack and the brightness of the groove in the gray image are different, namely the gray values are different, the crack possibility can be obtained by combining the curvature and the gray average of the edge lines for preliminary distinction, and a first edge line closer to the crack defect and a second edge line closer to the groove are obtained; because some fine crack edges can not be obtained by conventional edge detection, the first edge line is extended through the distance between the non-edge pixel point in the double-threshold interval and the nearest target edge line during the edge detection, and a complete extended first edge line is obtained; and because the number of the grooves around the concrete surface crack defect is less than that around the groove, the crack edge line is further determined by combining the characteristic and the crack possibility of the first edge line, so that the crack edge line is more accurate, and the obtained quality evaluation result of the concrete surface is more accurate.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.

Claims (8)

1. The concrete curing quality analysis method based on visual inspection is characterized by comprising the following steps:
acquiring a gray image of the surface of the concrete to be detected;
acquiring edge lines in the gray level image and non-edge pixel points in the middle of double thresholds during edge detection as candidate pixel points;
obtaining the curvature of each edge line according to the number of pixel points on each edge line and the coordinates of the pixel points; obtaining the crack possibility of each edge line according to the gray average value and the bending degree of each edge line;
dividing the edge line into a first edge line and a second edge line according to the crack possibility, wherein the crack possibility of the first edge line is greater than that of the second edge line;
obtaining a target edge line with the shortest distance between each first edge line by using the distance between the end point of each first edge line and the end points of other first edge lines, and taking the end point with the shortest distance between each first edge line and the target edge line as a target end point;
determining whether the first edge line is extended or not according to whether candidate pixel points exist in the target end point neighborhood of each first edge line and the distance between the candidate pixel points when the candidate pixel points exist and the end points of the corresponding target edge lines, and recalculating the crack possibility of the extended first edge line;
and marking the first edge lines which are not extended and the first edge lines which are extended as third edge lines, determining crack edge lines according to the number of second edge lines in the minimum circumscribed rectangle of each third edge line and the crack possibility of the third edge lines, and evaluating the maintenance quality of the concrete according to the area occupation ratio of the crack edge lines in the gray level image.
2. The visual inspection-based concrete curing quality analysis method according to claim 1, wherein the step of obtaining the curvature of each edge line comprises:
obtaining an absolute value of a slope of a connecting line between the starting point and the end point of each edge line according to coordinates of the starting point and the end point of the pixel point on each edge line in the gray-scale image, and taking the absolute value as a reference slope;
obtaining the slope absolute value of the connection line of each pixel point and the starting point according to the coordinates of each pixel point and the starting point on each edge line;
and calculating the mean value of the absolute value of the difference value between the slope absolute value of each pixel point on each edge line and the connecting line of the starting point and the reference slope, and normalizing the obtained mean value to obtain the curvature of each edge line.
3. The visual inspection-based concrete curing quality analysis method of claim 1, wherein the step of determining whether to extend the first edge line comprises:
taking a target endpoint of the first edge line as a seed point, and if no candidate pixel point exists in the neighborhood of the seed point, not extending the first edge line;
if candidate pixel points exist in the neighborhood of the seed point, acquiring the candidate pixel point with the maximum gradient in the neighborhood as a target candidate point;
and if the minimum distance between the target candidate point and the corresponding target edge line end point is not less than the distance between the target end point and the target edge line end point, not extending the first edge line, if the minimum distance is less than the distance, extending the first edge line to the target candidate pixel point, and continuously taking the target candidate pixel point as a new seed point to determine whether to extend the first edge line.
4. The visual inspection-based concrete curing quality analysis method according to claim 1, wherein the formula for obtaining the crack probability of each edge line is as follows:
Figure 302517DEST_PATH_IMAGE001
wherein ,
Figure 891761DEST_PATH_IMAGE002
is shown as
Figure 937078DEST_PATH_IMAGE003
The possibility of cracking of the edge lines;
Figure 738812DEST_PATH_IMAGE004
denotes the first
Figure 84342DEST_PATH_IMAGE003
Curvature of a border line;
Figure 313330DEST_PATH_IMAGE005
denotes the first
Figure 111521DEST_PATH_IMAGE006
Curvature of a border line;
Figure 215481DEST_PATH_IMAGE007
representing the total number of edge lines in the grayscale image;
Figure 149939DEST_PATH_IMAGE008
representing the curvature mean value of all edge lines in the gray level image;
Figure 549828DEST_PATH_IMAGE009
denotes the first
Figure 835316DEST_PATH_IMAGE006
Normalizing the gray level mean value of the edge line of the strip;
Figure 837907DEST_PATH_IMAGE010
is shown as
Figure 767816DEST_PATH_IMAGE003
Normalizing the gray level mean value of the edge line of the strip;
Figure 728819DEST_PATH_IMAGE011
representing the mean of the grey levels of all edge lines in a grey-scale imageA mean of the normalized values;
Figure 111390DEST_PATH_IMAGE012
is a normalization function.
5. The visual inspection-based concrete curing quality analysis method of claim 1, wherein the step of determining a crack edge line comprises:
the final crack probability of each third edge line is obtained by the following formula:
Figure 917672DEST_PATH_IMAGE013
wherein ,
Figure 463273DEST_PATH_IMAGE014
is shown as
Figure 329598DEST_PATH_IMAGE003
The ultimate likelihood of cracking of the third edge line of the strip;
Figure 465044DEST_PATH_IMAGE002
is shown as
Figure 809438DEST_PATH_IMAGE003
The possibility of cracking of the third edge line of the strip;
Figure 776257DEST_PATH_IMAGE015
is shown as
Figure 125068DEST_PATH_IMAGE003
The area of the minimum circumscribed rectangle of the third edge line;
Figure 544548DEST_PATH_IMAGE016
denotes the first
Figure 36840DEST_PATH_IMAGE003
The number of second edge lines in the minimum circumscribed rectangle of the third edge line;
Figure 562893DEST_PATH_IMAGE017
is an exponential function with a natural constant e as a base;
and determining a third edge line with the final crack possibility larger than a preset crack threshold value as a crack edge line.
6. The visual inspection-based concrete curing quality analysis method of claim 1, wherein the step of obtaining a target edge line with each first edge line closest to the target edge line comprises:
acquiring the minimum distance between the end point of each first edge line and the end points of other first edge lines;
selecting a minimum value from all the minimum distances obtained from each first edge line;
and taking the first edge line corresponding to the minimum value as the target edge line with the shortest distance from the first edge line.
7. The visual inspection-based concrete curing quality analysis method as claimed in claim 1, wherein the step of evaluating the curing quality of the concrete according to the area ratio of the crack edge lines in the gray-scale image comprises:
if the area proportion of the crack edge lines in the gray-scale image is smaller than a preset first area threshold value, the maintenance quality of the concrete is qualified;
if the area proportion of the crack edge line in the gray-scale image is larger than or equal to the first area threshold value and smaller than the preset second area threshold value, the concrete curing quality is poor;
and if the area ratio of the crack edge line in the gray-scale image is greater than or equal to the second area threshold value, the curing quality of the concrete is unqualified.
8. The visual inspection-based concrete curing quality analysis method according to claim 1, wherein the step of dividing the edge line into a first edge line and a second edge line according to crack probability comprises:
setting a crack possibility threshold value, and taking an edge line with the crack possibility larger than the crack possibility threshold value as a first edge line;
and taking the edge line with the crack possibility smaller than or equal to the crack possibility threshold value as a second edge line.
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Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN116228777A (en) * 2023-05-10 2023-06-06 鱼台汇金新型建材有限公司 Concrete stirring uniformity detection method
CN116645363A (en) * 2023-07-17 2023-08-25 山东富鹏生物科技有限公司 Vision-based starch production quality real-time detection method
CN116703907A (en) * 2023-08-04 2023-09-05 合肥亚明汽车部件有限公司 Machine vision-based method for detecting surface defects of automobile castings
CN116958182A (en) * 2023-09-20 2023-10-27 广东华宸建设工程质量检测有限公司 Quick concrete crack detection method based on image data
CN116993740A (en) * 2023-09-28 2023-11-03 山东万世机械科技有限公司 Concrete structure surface defect detection method based on image data
CN117095004A (en) * 2023-10-20 2023-11-21 金成技术股份有限公司 Excavator walking frame main body welding deformation detection method based on computer vision
CN117351021A (en) * 2023-12-06 2024-01-05 东莞市南谷第电子有限公司 Intelligent detection method for production quality of photovoltaic connecting wire
CN117423046A (en) * 2023-12-19 2024-01-19 山东水利建设集团有限公司 Visual detection method for cement mortar stirring process based on image processing

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008039594A (en) * 2006-08-07 2008-02-21 Yamaguchi Univ Crack detection method for concrete foundation pile
CN108007355A (en) * 2017-10-20 2018-05-08 西安电子科技大学 Distress in concrete detection method based on Image distance transform
CN110175658A (en) * 2019-06-26 2019-08-27 浙江大学 A kind of distress in concrete recognition methods based on YOLOv3 deep learning
CN110390669A (en) * 2019-06-26 2019-10-29 杭州电子科技大学 The detection method in crack in a kind of bridge image
CN112785579A (en) * 2021-01-26 2021-05-11 西京学院 Concrete crack identification method based on image processing technology
CN114454325A (en) * 2022-01-21 2022-05-10 四川农业大学 Maintenance system and production method of prefabricated concrete component for assembly type building
CN115082419A (en) * 2022-07-14 2022-09-20 江苏诺阳家居科技有限公司 Blow-molded luggage production defect detection method
CN115082462A (en) * 2022-08-22 2022-09-20 山东海鑫达石油机械有限公司 Method and system for detecting appearance quality of fluid conveying pipe

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008039594A (en) * 2006-08-07 2008-02-21 Yamaguchi Univ Crack detection method for concrete foundation pile
CN108007355A (en) * 2017-10-20 2018-05-08 西安电子科技大学 Distress in concrete detection method based on Image distance transform
CN110175658A (en) * 2019-06-26 2019-08-27 浙江大学 A kind of distress in concrete recognition methods based on YOLOv3 deep learning
CN110390669A (en) * 2019-06-26 2019-10-29 杭州电子科技大学 The detection method in crack in a kind of bridge image
CN112785579A (en) * 2021-01-26 2021-05-11 西京学院 Concrete crack identification method based on image processing technology
CN114454325A (en) * 2022-01-21 2022-05-10 四川农业大学 Maintenance system and production method of prefabricated concrete component for assembly type building
CN115082419A (en) * 2022-07-14 2022-09-20 江苏诺阳家居科技有限公司 Blow-molded luggage production defect detection method
CN115082462A (en) * 2022-08-22 2022-09-20 山东海鑫达石油机械有限公司 Method and system for detecting appearance quality of fluid conveying pipe

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
YUSUKE FUJITA ET AL: "A Method for Crack Detection on a Concrete Structure", 《18TH INTERNATIONAL CONFERENCE ON PATTERN RECOGNITION (ICPR\'06)》, pages 1 - 4 *
丁威等: "基于深度学习和无人机的混凝土结构裂缝检测方法", 《土木工程学报》, vol. 64, pages 1 - 12 *

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN116228777A (en) * 2023-05-10 2023-06-06 鱼台汇金新型建材有限公司 Concrete stirring uniformity detection method
CN116645363A (en) * 2023-07-17 2023-08-25 山东富鹏生物科技有限公司 Vision-based starch production quality real-time detection method
CN116645363B (en) * 2023-07-17 2023-10-13 山东富鹏生物科技有限公司 Vision-based starch production quality real-time detection method
CN116703907A (en) * 2023-08-04 2023-09-05 合肥亚明汽车部件有限公司 Machine vision-based method for detecting surface defects of automobile castings
CN116703907B (en) * 2023-08-04 2023-10-27 合肥亚明汽车部件有限公司 Machine vision-based method for detecting surface defects of automobile castings
CN116958182B (en) * 2023-09-20 2023-12-08 广东华宸建设工程质量检测有限公司 Quick concrete crack detection method based on image data
CN116958182A (en) * 2023-09-20 2023-10-27 广东华宸建设工程质量检测有限公司 Quick concrete crack detection method based on image data
CN116993740A (en) * 2023-09-28 2023-11-03 山东万世机械科技有限公司 Concrete structure surface defect detection method based on image data
CN116993740B (en) * 2023-09-28 2023-12-19 山东万世机械科技有限公司 Concrete structure surface defect detection method based on image data
CN117095004A (en) * 2023-10-20 2023-11-21 金成技术股份有限公司 Excavator walking frame main body welding deformation detection method based on computer vision
CN117095004B (en) * 2023-10-20 2024-01-12 金成技术股份有限公司 Excavator walking frame main body welding deformation detection method based on computer vision
CN117351021A (en) * 2023-12-06 2024-01-05 东莞市南谷第电子有限公司 Intelligent detection method for production quality of photovoltaic connecting wire
CN117351021B (en) * 2023-12-06 2024-03-26 东莞市南谷第电子有限公司 Intelligent detection method for production quality of photovoltaic connecting wire
CN117423046A (en) * 2023-12-19 2024-01-19 山东水利建设集团有限公司 Visual detection method for cement mortar stirring process based on image processing
CN117423046B (en) * 2023-12-19 2024-03-01 山东水利建设集团有限公司 Visual detection method for cement mortar stirring process based on image processing

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