CN114659627A

CN114659627A - Laser spot monitoring method, system and equipment based on annular filtering

Info

Publication number: CN114659627A
Application number: CN202210526133.7A
Authority: CN
Inventors: 杨祖元; 李陵江; 李茂林; 李尚明; 谢胜利
Original assignee: Guangdong University of Technology
Current assignee: Ante Laser Co ltd
Priority date: 2022-05-16
Filing date: 2022-05-16
Publication date: 2022-06-24
Anticipated expiration: 2042-05-16
Also published as: CN114659627B

Abstract

The invention discloses a laser spot monitoring method, a system and equipment based on annular filtering. And carrying out iterative updating on the initial long axis and a preset initial short axis, and calculating by combining the gray value coordinate, the target center coordinate and the target inclination angle to determine the target long axis and the target short axis. And finally, fitting an ellipse on the light spot image by adopting the target long axis, the target short axis, the target center coordinate and the target inclination angle to determine light spot parameters such as the position and the size of the light spot corresponding to the light spot image, and improving the measurement accuracy and the robustness of the light spot parameters according to the statistical information of the light spot gray value and the Gaussian distribution characteristics of the light spot.

Description

Laser spot monitoring method, system and equipment based on annular filtering

Technical Field

The invention relates to the technical field of laser spot monitoring, in particular to a laser spot monitoring method, a laser spot monitoring system and laser spot monitoring equipment based on annular filtering.

Background

With the continuous development of science and technology, laser technology is widely applied in the fields of medicine, measurement, communication, industry, military and the like. In the use process of the laser-based equipment, the requirement on the quality of a laser beam is high, and the quality of the laser beam is generally evaluated by adopting spot parameters such as the shape, the size, the central coordinate, the energy distribution and the like of a laser spot. Therefore, it is necessary to measure and analyze the laser spot in real time when the device is in operation.

At present, common laser spot measuring methods include a moving slit method, a moving knife edge method and an optical imaging method. The optical imaging method has higher measurement speed and higher measurement precision, and can meet the requirements of non-contact and dynamic automatic measurement. Therefore, optical imaging has become a common laser spot measurement method.

The laser spot measuring method based on the optical imaging method comprises an amplitude critical value method, a power flux method and a second moment definition method provided by the international standard organization. The three measurement modes have high requirements on the selection of the size of the region of interest and the change of the ambient background light, so the required structure is complex, and the robustness is poor.

Disclosure of Invention

The invention provides a laser spot monitoring method, a laser spot monitoring system and laser spot monitoring equipment based on annular filtering, and solves the technical problems that the existing laser spot measuring method has high requirements on the selection of the size of an interested area and the change of ambient background light, the required structure is complex, and the robustness is poor.

The invention provides a laser spot monitoring method based on annular filtering, which comprises the following steps:

when a light spot image corresponding to target equipment is acquired, determining a target center coordinate and a target inclination angle according to a gray value coordinate acquired from the light spot image;

determining an initial long axis according to the target center coordinate and the gray value coordinate;

according to the gray value coordinates, the target center coordinates and the target inclination angle, performing iterative updating on the initial long shaft and a preset initial short shaft to determine a target long shaft and a target short shaft;

and fitting an ellipse by adopting the target long axis, the target short axis, the target center coordinate and the target inclination angle to determine the light spot parameters corresponding to the light spot image.

Optionally, the step of determining a target center coordinate and a target inclination angle according to a gray value coordinate acquired from the light spot image when the light spot image corresponding to the target device is acquired includes:

when a light spot image corresponding to target equipment is acquired, calculating a background gray average value in the light spot image in an elliptical ring shape;

carrying out differential calculation on the light spot image by adopting the background gray average value to obtain a gray value coordinate;

constructing an initial annular aperture by taking the maximum gray value coordinate in the gray value coordinates as a center and combining preset major and minor axis parameters;

calculating the maximum value and the minimum value of the initial distance from the maximum gray value coordinate to the initial annular aperture;

taking the maximum gray value coordinate as the center of an interested area, and initializing the interested area by combining the maximum initial distance value and the minimum initial distance value;

respectively calculating the central coordinate and the inclination angle corresponding to the region of interest by combining the gray information in the region of interest with a preset statistical moment formula;

iteratively updating the center coordinates and the tilt angle based on the aperture attenuation results for the initial annular aperture, determining target center coordinates and target tilt angle.

Optionally, the step of determining the target center coordinate and the target tilt angle by iteratively updating the center coordinate and the tilt angle based on the result of the aperture attenuation for the initial annular aperture comprises:

carrying out aperture attenuation on the initial annular aperture by using a preset attenuation value to obtain an attenuated annular aperture;

calculating the maximum distance value and the minimum distance value from the center coordinate to the attenuation annular aperture;

taking the central coordinates as the center of the region of interest, and combining the distance maximum value and the distance minimum value to generate a new region of interest;

updating the initial annular aperture to be the attenuation annular aperture, and skipping to execute the step of respectively calculating the central coordinate and the inclination angle corresponding to the region of interest by adopting the gray information in the region of interest and combining a preset statistical moment formula;

and when the central coordinate and the inclination angle are converged, determining the central coordinate at the current moment as a target central coordinate, and determining the inclination angle at the current moment as a target inclination angle.

Optionally, the step of determining an initial long axis according to the target center coordinate and the gray value coordinate includes:

calculating the length between the target center coordinate and the maximum value of the gray value coordinate;

and calculating the length by adopting a first preset percentage value to determine an initial long axis.

Optionally, the step of iteratively updating the initial long axis and a preset initial short axis according to the gray value coordinates, the target center coordinates, and the target tilt angle to determine a target long axis and a target short axis includes:

iteratively updating the initial long axis and a preset initial short axis according to the gray value coordinate, the target center coordinate, the target inclination angle and a preset initial step length until the initial short axis is greater than or equal to the initial long axis to obtain a middle long axis and a middle short axis;

calculating an intermediate ratio of the intermediate major axis to the intermediate minor axis;

calculating a undetermined long shaft by adopting a long shaft statistical moment formula according to the intermediate ratio, the target center coordinate and the target inclination angle;

and iteratively updating the undetermined long shaft according to a preset target step length until the undetermined long shaft meets a preset energy ratio condition, and determining the target long shaft and the target short shaft by adopting the undetermined long shaft and the intermediate ratio.

Optionally, the step of iteratively updating the initial long axis and the preset initial short axis according to the gray value coordinate, the target center coordinate, the target tilt angle, and a preset initial step length until a middle long axis and a middle short axis are obtained when the initial short axis is greater than or equal to the initial long axis includes:

calculating the length between the target center coordinate and the maximum value of the gray value coordinate and combining a second preset percentage value to obtain a set length;

calculating an initial ratio between the initial long axis and a preset initial short axis;

iteratively updating the initial long axis and the initial short axis according to the initial ratio, the target center coordinate, the target inclination angle and a first initial step length, and generating an elliptical circular convolution characteristic;

when the initial long axis is larger than the set length, calculating the Euclidean distance between each elliptical annular convolution characteristic and a standard light spot characteristic;

resetting the initial long axis, and iteratively updating the initial short axis by combining a second initial step size to obtain a new initial ratio;

skipping to execute the step of iteratively updating the initial long axis and the initial short axis according to the initial ratio, the target center coordinate, the target inclination angle and a first initial step length, and generating an elliptical circular convolution characteristic;

and when the initial short axis is larger than the initial long axis, determining a middle long axis and a middle short axis according to the minimum Euclidean distance.

Optionally, the step of iteratively updating the initial major axis and the initial minor axis according to the initial ratio, the target center coordinate, the target tilt angle, and a first initial step size, and generating an elliptical circular convolution feature includes:

calculating to obtain an elliptical annular convolution kernel by adopting the initial long axis, the initial short axis, the target center coordinate and the target inclination angle;

calculating the convolution and the average of the elliptical circular convolution kernels to obtain elliptical circular convolution characteristics;

updating the initial short axis with a first initial step size, updating the initial long axis in combination with the initial ratio;

and skipping to execute the step of calculating to obtain an elliptical circular convolution kernel by adopting the initial long axis, the initial short axis, the target center coordinate and the target inclination angle.

Optionally, the preset energy ratio condition is a preset energy ratio range; the step of determining the target long axis and the target short axis by adopting the undetermined long axis and the intermediate ratio when the undetermined long axis is iteratively updated according to a preset target step length until the undetermined long axis meets a preset energy ratio condition comprises the following steps:

calculating the energy value of the region of interest by combining the intermediate ratio, the target center coordinate, the target inclination angle and a preset energy formula;

combining the undetermined long shaft with the intermediate ratio to calculate an undetermined short shaft;

calculating an ellipse energy value by combining the undetermined long shaft, the undetermined short shaft, the target center coordinate and the target inclination angle with the preset energy formula;

calculating an energy ratio of the elliptical energy value and the region of interest energy value;

iteratively updating the undetermined long shaft according to a preset target step length;

skipping to execute the step of combining the undetermined long shaft with the intermediate ratio and calculating to obtain an undetermined short shaft;

and when the energy ratio is in a preset energy ratio range, determining the undetermined long shaft at the current moment as a target long shaft, and determining the undetermined short shaft at the current moment as a target short shaft.

The invention provides a laser spot monitoring system based on annular filtering in a second aspect, which comprises:

the center coordinate and inclination angle determining module is used for determining a target center coordinate and a target inclination angle according to a gray value coordinate acquired from a light spot image when the light spot image corresponding to the target equipment is acquired;

the initial long axis determining module is used for determining an initial long axis according to the target center coordinate and the gray value coordinate;

the target long and short axis determining module is used for performing iterative updating on the initial long axis and a preset initial short axis according to the gray value coordinate, the target center coordinate and the target inclination angle to determine a target long axis and a target short axis;

and the light spot parameter determining module is used for fitting an ellipse by adopting the target long axis, the target short axis, the target center coordinate and the target inclination angle to determine the light spot parameters corresponding to the light spot image.

A third aspect of the present invention provides an electronic device, including a memory and a processor, where the memory stores a computer program, and the computer program, when executed by the processor, causes the processor to execute any one of the above-mentioned ring filter-based laser spot monitoring methods.

According to the technical scheme, the invention has the following advantages:

according to the invention, when the light spot image corresponding to the target equipment is acquired, the gray value coordinate acquired from the light spot image is adopted to determine the target center coordinate and the target inclination angle. And determining an initial long axis based on the distance relation between the target center coordinate and the gray value coordinate. And iteratively updating the initial long axis and the preset initial short axis, and calculating by combining the gray value coordinate, the target center coordinate and the target inclination angle to determine the target long axis and the target short axis. And finally, fitting an ellipse on the light spot image by adopting the target long axis, the target short axis, the target center coordinate and the target inclination angle so as to determine light spot parameters such as the position and the size of the light spot corresponding to the light spot image. The method solves the technical problems that the existing laser spot measurement method has high requirements on the selection of the size of an interested area and the change of ambient background light, the required structure is complex, and the robustness is poor, and can improve the measurement precision and robustness of spot parameters according to the statistical information of the spot gray value and the Gaussian distribution characteristics of spots.

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 description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without inventive exercise.

Fig. 1 is a flowchart illustrating steps of a laser spot monitoring method based on annular filtering according to an embodiment of the present invention;

fig. 2 is a flowchart illustrating steps of a laser spot monitoring method based on annular filtering according to a second embodiment of the present invention;

fig. 3 is a flowchart of an implementation process of a laser spot monitoring method based on annular filtering according to a third embodiment of the present invention;

fig. 4 is a light spot image of a target region of interest fitted with an ellipse according to a third embodiment of the present invention;

fig. 5 is a light spot image of a fitting ellipse after performing elliptical circular convolution filtering according to a third embodiment of the present invention;

fig. 6 is a light spot image after pseudo-colorization according to a third embodiment of the present invention;

fig. 7 is a block diagram of a laser spot monitoring system based on annular filtering according to a fourth embodiment of the present invention;

fig. 8 is a block diagram of an electronic device according to an embodiment of the present invention.

Detailed Description

The existing laser spot detection method generally obtains a spot center and a spot edge for analysis to obtain corresponding spot parameters, and the spot edge is determined according to the ratio of the long axis to the short axis of the spot. The following two methods are commonly used to determine the ratio of the spot center to the spot minor and major axes:

the method for determining the center of the light spot comprises the steps of determining the position and the size of an interested area according to key points and edge information in the light spot, and determining the center coordinate according to the related gray value of the interested area. However, the method has the disadvantages that the background gray value and the edge gray value in the region of interest are similar, and the background interference is large, so that the region of interest cannot be accurately determined. Moreover, statistical information of gray value distribution is not utilized, and a proper edge threshold value needs to be set, so that the operation is complex and the robustness is poor.

The method for determining the ratio of the long axis to the short axis of the light spot comprises the steps of carrying out smooth convolution preprocessing on the light spot, and fitting an ellipse according to the edge information of the light spot to determine the ratio. However, the method has the problems that background noise and edge information are difficult to distinguish, facula information is lost by using smooth convolution, and a proper edge threshold value needs to be set, so that the stability of the fitted ellipse is poor, the ratio precision is low, and the robustness is poor.

The embodiment of the invention provides a laser spot monitoring method, a laser spot monitoring system and laser spot monitoring equipment based on annular filtering, which are used for solving the technical problems that the existing laser spot measuring method has high requirements on the selection of the size of an interested area and the change of ambient background light, the required structure is complex and the robustness is poor.

In order to make the objects, features and advantages of the present invention more obvious and understandable, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the embodiments described below 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.

Referring to fig. 1, fig. 1 is a flowchart illustrating steps of a laser spot monitoring method based on annular filtering according to an embodiment of the present invention.

step 101, when a light spot image corresponding to the target device is acquired, determining a target center coordinate and a target inclination angle according to a gray value coordinate acquired from the light spot image.

The target equipment refers to a device capable of emitting laser, such as laser-based medical detection equipment, laser cutting equipment, photoelectric communication electronic products, optoelectronic military equipment and the like. The spot image is an image of a laser spot generated in the use process of the laser.

The gray value coordinate refers to the corresponding position of each gray value of the light spot image on the light spot image. The target center coordinate and the target inclination angle refer to the center coordinate and the inclination angle corresponding to the light spot on the light spot image.

In the embodiment of the invention, when the light spot image corresponding to the target device is acquired, the gray value distribution information and the gray value average value of the light spot image are counted by adopting an image processing device based on MATLAB, an image processing device based on FPGA and other devices according to the statistical characteristics of the signals, and the light spot image is differentiated by adopting the gray value distribution information and the gray value average value, so that the influence of the background gray value is removed. And iteratively updating the region of interest in the light spot image based on the light spot image without the influence of the background gray value, by combining gray value distribution information, the initial annular aperture and an attenuation annular aperture obtained by performing aperture attenuation on the initial annular aperture by using a preset attenuation value, and determining the target center coordinate and the target inclination angle when the center coordinate and the inclination angle are converged.

And 102, determining an initial long axis according to the target center coordinate and the gray value coordinate.

In the embodiment of the invention, the length from the target center coordinate to the maximum value of the gray value coordinate is calculated, then a part of the obtained length is intercepted according to a first preset percentage value, and the initial long axis is constructed according to the intercepted length.

And 103, iteratively updating the initial long axis and the preset initial short axis according to the gray value coordinate, the target center coordinate and the target inclination angle, and determining the target long axis and the target short axis.

The length of the preset initial short axis is a given length value, the length value is selected for different scenes and light spot images, and the length value is different, and a person skilled in the art can set the preset initial short axis as a corresponding length value according to different scenes and light spot images, which is not limited in this embodiment of the present invention.

In the embodiment of the invention, after the initial long axis is obtained based on the Gaussian distribution characteristics of the light spots, the initial long axis and the preset initial short axis are iteratively updated by a preset step length for determining the target long axis and the target short axis, and the undetermined long axis is obtained by calculating according to the gray value coordinate, the target center coordinate and the target inclination angle. And when the to-be-determined long axis meets a preset energy ratio condition, obtaining a target long axis and a target short axis.

And step 104, fitting an ellipse by adopting the target long axis, the target short axis, the target center coordinate and the target inclination angle, and determining the light spot parameters corresponding to the light spot image.

The spot parameters refer to the shape, size, center coordinates, tilt angle, energy distribution and other parameters of the spot.

In the embodiment of the invention, after the target long axis and the target short axis are obtained through iterative updating, in order to determine other spot parameters, the length corresponding to the target long axis and the target short axis can be adopted, and the ratio between the target long axis and the target short axis is calculated to obtain the ratio of the long axis to the short axis. And fitting an ellipse on the spot image by using the ratio of the long axis to the short axis and combining the target center coordinate and the target inclination angle to determine spot parameters such as the position and the size of the spot corresponding to the spot image.

In the embodiment of the invention, when the light spot image corresponding to the target equipment is acquired, the gray value coordinate acquired from the light spot image is adopted to determine the target center coordinate and the target inclination angle, and the initial long axis is determined based on the distance relationship between the target center coordinate and the gray value coordinate. And iteratively updating the initial long axis and the preset initial short axis by a preset step length, and calculating by combining the gray value coordinate, the target center coordinate and the target inclination angle to determine the target long axis and the target short axis. And finally, fitting an ellipse on the light spot image by adopting the target long axis, the target short axis, the target center coordinate and the target inclination angle so as to determine light spot parameters such as the position and the size of the light spot corresponding to the light spot image. The method solves the technical problems that the existing laser spot measurement method has high requirements on the selection of the size of an interested area and the change of ambient background light, the required structure is complex, and the robustness is poor, and can improve the measurement precision and robustness of spot parameters according to the statistical information of the spot gray value and the Gaussian distribution characteristics of spots.

Referring to fig. 2, fig. 2 is a flowchart illustrating steps of a laser spot monitoring method based on annular filtering according to a second embodiment of the present invention;

step 201, when a light spot image corresponding to the target device is acquired, determining a target center coordinate and a target inclination angle according to a gray value coordinate acquired from the light spot image.

Further, step 201 may include the following sub-steps S11-S17:

and S11, when the light spot image corresponding to the target equipment is acquired, calculating the background gray level mean value in the light spot image by an elliptical ring.

The gray value refers to the brightness corresponding to each pixel point on the light spot image.

In the embodiment of the invention, after the light spot image corresponding to the target device is acquired, the gray value coordinate corresponding to the brightest point, namely the maximum gray value, on the light spot image and the preset initial major and minor axis parameters are acquired, an elliptical ring is constructed on the light spot image, and the sum of all gray values in the elliptical ring is averaged to obtain the background gray average value.

It should be noted that, for different scenes, spot images generated by different types of lasers are different, and those skilled in the art may set corresponding initial major and minor axis parameters according to different scenes and spot images, which is not limited in this embodiment of the present invention.

And S12, carrying out differential calculation on the light spot image by adopting the background gray average value to obtain a gray value coordinate.

The gray value coordinates refer to pixel coordinates corresponding to each remaining gray value on the light spot image after eliminating the influence of the background gray value.

The maximum gray value coordinate refers to the pixel coordinate corresponding to the maximum gray value in a certain image range.

In the embodiment of the invention, the difference calculation is carried out on each gray value in the light spot image by adopting the background gray average value, the gray value smaller than the background gray average value on the light spot image is deleted, so that the influence of the background gray value on the light spot image is eliminated, and then the pixel coordinate corresponding to each gray value is obtained to obtain the gray value coordinate.

And S13, constructing an initial annular aperture by taking the maximum gray value coordinate in the gray value coordinates as the center and combining preset major and minor axis parameters.

In the embodiment of the invention, the maximum gray value coordinate in the gray value coordinates is calculated, the maximum gray value coordinate is taken as the center, the preset major axis and minor axis parameters are taken as the major axis and the minor axis, the initial annular aperture is constructed, and the attenuation area of the annular aperture is initialized.

And S14, calculating the maximum value and the minimum value of the initial distance from the maximum gray value coordinate to the initial annular diaphragm.

In the embodiment of the invention, after the initial annular aperture is constructed, the pixel point coordinates corresponding to each gray value in the initial annular aperture are obtained, and the corresponding distance value is obtained by combining the maximum gray value coordinate for calculation. And obtaining the maximum value and the minimum value of the initial distance by using the maximum value and the minimum value of the distance from the maximum gray value coordinate to the initial annular aperture.

And S15, initializing the region of interest by taking the maximum gray value coordinate as the center of the region of interest and combining the maximum value of the initial distance and the minimum value of the initial distance.

The region of interest, also called ROI region, refers to a region to be processed, which is delineated from a processed image in a manner of a square, a circle, an ellipse, an irregular polygon, etc. in machine vision and image processing. The area needing to be processed is outlined in an oval manner in the spot image in the embodiment of the invention.

In the embodiment of the invention, the maximum gray value coordinate in the gray value coordinates is used as the center of the region of interest, and an ellipse is fitted by combining the gray information of the light spot image, the maximum value of the initial distance of n times and the minimum value of the initial distance of n times to obtain the initialized region of interest. The skilled person can select the initial distance maximum value and the initial distance minimum value of the corresponding multiple according to the gray scale information of the spot image to initialize the region of interest.

And S16, respectively calculating the central coordinate and the inclination angle corresponding to the region of interest by combining the gray information in the region of interest with a preset statistical moment formula.

The gray information in the region of interest refers to each gray value and each gray value coordinate in the region of interest; the preset statistical moment formula comprises a central coordinate formula and an inclination angle formula, and the central coordinate formula and the inclination angle formula are respectively as follows:

(1) calculating center coordinates

：

，

(2) Calculating the tilt angle

：

Wherein,

is a gray value within the region of interest,m=4dmax being the length of the region of interest,n=4dmin is the width of the region of interest,

and dmax is the maximum distance value between the central coordinate of the region of interest and the attenuation ring aperture, and dmin is the minimum distance value between the central coordinate of the region of interest and the attenuation ring aperture.

In the embodiment of the invention, the gray value and the gray value coordinate in the region of interest are substituted into a preset statistical moment formula for calculation, the central coordinate formula of the region of interest is adopted to calculate the central coordinate of the region of interest, and the inclination angle formula of the region of interest is adopted to calculate the inclination angle of the region of interest.

And S17, iteratively updating the center coordinate and the inclination angle based on the aperture attenuation result of the initial annular aperture, and determining the target center coordinate and the target inclination angle.

Optionally, S17 may include the following sub-steps S171-S175:

and S171, performing aperture attenuation on the initial annular aperture by using a preset attenuation value to obtain an attenuated annular aperture.

The preset attenuation value is a numerical value corresponding to each attenuation amplitude of the annular aperture by combining the gray information of the light spot image and the initial annular aperture.

In the embodiment of the invention, according to a preset attenuation value, the initial annular aperture is subjected to aperture attenuation by corresponding attenuation amplitude to obtain an attenuation annular aperture, and a new region of interest is obtained by calculating according to a central coordinate and an inclination angle. And then, carrying out aperture attenuation on the attenuation annular aperture according to a preset attenuation value, so that the attenuation amplitude of the attenuation annular aperture is the same every time, and obtaining different attenuation annular apertures.

And S172, calculating the maximum distance value and the minimum distance value from the center coordinate to the attenuation ring-shaped diaphragm.

In the embodiment of the invention, the attenuation annular diaphragm is attenuated according to a preset attenuation value to obtain a new attenuation annular diaphragm, a new central coordinate and a new inclination angle are calculated by combining a preset statistical moment formula, the central coordinate is combined with a gray value coordinate in the attenuation annular diaphragm to calculate, and the maximum value and the minimum value of the distance from the central coordinate to the attenuation annular diaphragm are obtained.

And S173, generating a new region of interest by taking the center coordinates as the center of the region of interest and combining the distance maximum value and the distance minimum value.

In the embodiment of the invention, after the maximum distance value and the minimum distance value from the updated central coordinate to the attenuation ring-shaped aperture are obtained, a new region of interest is constructed by combining the central coordinate and the inclination angle.

And S174, updating the initial annular aperture into an attenuation annular aperture, and skipping to execute the step of respectively calculating the central coordinate and the inclination angle corresponding to the region of interest by adopting the gray scale information in the region of interest and combining a preset statistical moment formula.

In the embodiment of the invention, the initial annular aperture is updated to the attenuation annular aperture, and a new region of interest is constructed by combining the newly updated central coordinate and the newly updated inclination angle. And calculating by adopting a preset statistical moment formula and combining with the gray information in the region of interest, and updating the central coordinate and the inclination angle again. And attenuating the attenuation annular aperture by using a preset attenuation value, calculating by combining the corresponding central coordinate and the corresponding inclination angle, generating a new region of interest again, and repeating iterative updating until the central coordinate and the inclination angle are converged, and stopping the iterative updating.

When the center coordinates and the tilt angle converge, S175 determines the center coordinates at the current time as the target center coordinates, and determines the tilt angle at the current time as the target tilt angle.

The target center coordinate refers to the center of the light spot in the light spot image; the target tilt angle refers to the tilt angle of the spot in the spot image.

In the embodiment of the invention, when the central coordinate and the inclination angle are respectively the same in the iterative updating process of two or more adjacent times, the central coordinate at the current moment is taken as the central coordinate of the target, the inclination angle at the current moment is taken as the target inclination angle, and the calculation is carried out by combining the corresponding attenuation annular aperture to determine the target region of interest.

Step 202, calculating the length between the target center coordinate and the maximum value of the gray value coordinate.

In the embodiment of the present invention, the maximum value of the gray scale value coordinate is also referred to as a maximum gray scale value coordinate, and refers to a pixel coordinate corresponding to the maximum gray scale value in the target region of interest. And calculating the maximum gray value coordinate in the target interest area by combining the target center coordinate to obtain the length from the target center coordinate to the maximum gray value coordinate.

And 203, calculating the length by adopting the first preset percentage value, and determining the initial long axis.

In the embodiment of the invention, after the length between the target center coordinate and the maximum gray value coordinate is calculated, a part of the obtained length is intercepted according to a first preset percentage value, and finally, an initial long axis is constructed according to the intercepted length.

And 204, performing iterative update on the initial long axis and a preset initial short axis according to the gray value coordinate, the target center coordinate and the target inclination angle, and determining the target long axis and the target short axis.

Optionally, step 204 may include the following sub-steps S21-S24:

and S21, iteratively updating the initial long axis and the preset initial short axis according to the gray value coordinate, the target center coordinate, the target inclination angle and the preset initial step length until the initial short axis is larger than or equal to the initial long axis, and obtaining a middle long axis and a middle short axis.

Optionally, S21 may include the following sub-steps S211-S217:

s211, calculating the length between the target center coordinate and the maximum value of the gray value coordinate and combining the length with a second preset percentage value to obtain a set length.

In the embodiment of the invention, the lengths of the target center coordinate and the maximum gray value coordinate in the target region of interest are calculated, then a part of the obtained lengths is intercepted according to a second preset percentage value, and finally the intercepted length is used as the set length.

S212, calculating an initial ratio between the initial long axis and a preset initial short axis.

In the embodiment of the invention, the ratio of the initial long axis constructed according to the length obtained by intercepting the first preset percentage value to the preset initial short axis is obtained to obtain the initial ratio.

The preset initial short axis is set by a person skilled in the art by combining the target center coordinate, the target tilt angle, and the target region of interest, and the person skilled in the art may set the corresponding preset initial short axis by combining different calculated target center coordinates, target tilt angles, and target regions of interest, which is not limited in this embodiment of the present invention.

And S213, iteratively updating the initial long axis and the initial short axis according to the initial ratio, the target center coordinate, the target inclination angle and the first initial step length, and generating an elliptical circular convolution characteristic.

Optionally, S213 may comprise the following sub-steps S2131-S2134:

s2131, calculating to obtain an elliptical circular convolution kernel by adopting the initial long axis, the initial short axis, the target center coordinate and the target inclination angle.

In the embodiment of the present invention, the formula of the elliptical circular convolution kernel is:

wherein,

is a coordinate of a gray value and is,

is the coordinate of the center of the ellipse,a、bthe length of the long short shaft is the same as the length of the short shaft,

is an elliptical tilt angle.

And constructing a corresponding region of interest by using the initial long axis, the initial short axis, the target center coordinate and the target inclination angle. And calculating by taking the target center coordinate as an ellipse center coordinate and the target inclination angle as an ellipse inclination angle and combining the gray value coordinate in the region of interest and an elliptical circular convolution kernel formula to obtain the major axis and the minor axis of the convolution kernel. And constructing an elliptical annular convolution kernel by combining the target center coordinate and the target inclination angle according to the long axis and the short axis of the convolution kernel.

S2132, calculating the convolution and the average of the elliptical circular convolution kernels to obtain elliptical circular convolution characteristics.

In the embodiment of the invention, the characteristic formula is as follows:

wherein,

is the gray value on the elliptical circular convolution kernel,Nis the number of gray values on the elliptical circular convolution kernel.

And calculating the sum of the number of the gray values in the elliptical circular convolution kernel, and performing convolution and averaging by combining all the gray values in the elliptical circular convolution kernel and a characteristic formula to obtain elliptical circular convolution characteristics.

S2133, the initial minor axis is updated with the first initial step size, and the initial major axis is updated with the initial ratio.

In the embodiment of the invention, the initial short axis is updated by adopting the first initial step size, and the updated initial long axis is obtained by combining the initial ratio. Setting of the first initial step size, a person skilled in the art may set the first initial step size by combining with the gray scale information of the light spot image, which is not limited in this embodiment of the present invention.

And S2134, skipping and executing the step of calculating to obtain an elliptical circular convolution kernel by adopting the initial long axis, the initial short axis, the target center coordinate and the target inclination angle.

In the embodiment of the invention, after the updated initial long axis and initial short axis are obtained, the calculation is carried out by combining the target center coordinate and the target inclination angle, a new elliptical circular convolution kernel is constructed, and the convolution and averaging are carried out on the elliptical circular convolution kernel to obtain a new elliptical circular convolution characteristic. And updating the initial short axis by the first initial step length, and performing iterative updating by combining the initial ratio update initial long axis to obtain the corresponding elliptic circular convolution characteristics.

And S214, when the initial long axis is larger than the set length, calculating the Euclidean distance between each elliptic annular convolution feature and the standard light spot feature.

Euclidean distance, also known as euclidean distance, is a commonly used definition of distance, referring to the true distance between two points in an m-dimensional space, or the natural length of a vector (i.e., the distance of the point from the origin).

In the embodiment of the invention, when the initial long axis is longer than the set length obtained by calculation in the step S211, the elliptical circular convolution characteristics and the standard light spot characteristics at the same ratio are respectively calculated to obtain the corresponding euclidean distance.

S215, resetting the initial long axis, and iteratively updating the initial short axis by combining the second initial step size to obtain a new initial ratio.

In the embodiment of the invention, after the Euclidean distances between the elliptic annular convolution characteristics and the standard light spot characteristics under the same ratio are calculated, the initial long axis is reset, namely the initial long axis is obtained by constructing a part of the length obtained by intercepting the initial long axis according to the first preset percentage value, and the initial short axis is iteratively updated by using the second initial step length to obtain the corresponding initial ratio.

S216, performing jumping to perform the steps of iteratively updating the initial long axis and the initial short axis according to the initial ratio, the target center coordinate, the target inclination angle and the first initial step length, and generating the elliptical circular convolution characteristics.

In the embodiment of the invention, the initial short axis is iteratively updated by a second initial step size, the initial long axis is reset to obtain a new initial ratio, the initial long axis and the initial short axis are iteratively updated by the new initial ratio, and the corresponding elliptic annular convolution kernel characteristic is generated. And when the initial long axis is larger than the set length, calculating the Euclidean distance between each elliptic annular convolution characteristic and the standard light spot characteristic. And repeating the steps to perform iterative updating.

And S217, when the initial short axis is larger than the initial long axis, determining a middle long axis and a middle short axis according to the minimum Euclidean distance.

In the embodiment of the invention, when the initial short axis is larger than the reset initial long axis, the minimum Euclidean distance in Euclidean distances obtained by the elliptic annular convolution characteristics and the standard light spot characteristics is calculated, the initial long axis corresponding to the minimum Euclidean distance is used as the middle long axis, and the initial short axis corresponding to the minimum Euclidean distance is used as the middle short axis.

S22, calculating the middle ratio of the middle long axis to the middle short axis.

In the embodiment of the invention, when the initial short axis of the iterative update is larger than the initial long axis, the minimum value of the Euclidean distance in the Euclidean distance is calculated to obtain the middle long axis and the middle short axis, and the middle long axis and the middle short axis are compared to obtain the middle ratio.

And S23, calculating the undetermined long axis by adopting a long axis statistical moment formula according to the intermediate ratio, the target center coordinate and the target inclination angle.

In the embodiment of the present invention, the long axis statistical moment formula is:

wherein,

is a gray value within the region of interest,m=4dmax is the length of the region of interest,n=4dmin is the width of the region of interest,

are the gray value coordinates within the region of interest,

is the tilt angle.

And constructing the region of interest by using the target center coordinate, the target inclination angle and the middle long axis and the middle short axis corresponding to the middle ratio. And calculating by combining gray information in the region of interest and a long axis statistical moment formula to determine the undetermined long axis.

And S24, iteratively updating the undetermined long shaft according to a preset target step length until the undetermined long shaft meets a preset energy ratio condition, and determining the target long shaft and the target short shaft by adopting the undetermined long shaft and a middle ratio.

Optionally, S24 may include the following sub-steps S241-S247:

and S241, calculating the energy value of the region of interest by combining the intermediate ratio, the target center coordinate, the target inclination angle and a preset energy formula.

In an embodiment of the invention, the region of interest is determined by combining the target center coordinates and the target tilt angle with the intermediate major axis and the intermediate minor axis corresponding to the intermediate ratio. And (4) calculating by adopting gray information in the region of interest and combining a preset energy formula to obtain the energy value of the region of interest.

And S242, combining the undetermined long shaft with the intermediate ratio, and calculating to obtain the undetermined short shaft.

In the embodiment of the invention, the undetermined long shaft is obtained by calculating by combining the intermediate ratio with a long shaft statistical moment formula, and the undetermined short shaft is obtained by calculating by combining the undetermined long shaft with the intermediate ratio.

And S243, calculating the ellipse energy value by combining the undetermined long axis, the undetermined short axis, the target center coordinate and the target inclination angle with a preset energy calculation formula.

In the embodiment of the invention, the ellipse is fitted by the undetermined major axis, the undetermined minor axis, the target center coordinate and the target inclination angle, and the gray information in the ellipse is combined with the preset energy calculation formula to calculate so as to obtain the ellipse energy value.

And S244, calculating the energy ratio of the ellipse energy value and the region of interest energy value.

In the embodiment of the invention, the ellipse energy value is calculated by adopting the undetermined long axis, the undetermined short axis, the target center coordinate and the target inclination angle and combining a preset energy calculation formula. The energy value of the region of interest is calculated by combining a preset energy calculation formula by using the intermediate ratio, the target center coordinate and the target inclination angle. And comparing the elliptical energy value with the energy value of the region of interest to obtain an energy ratio.

And S245, iteratively updating the undetermined long shaft according to a preset target step length.

In the embodiment of the invention, the intermediate ratio is unchanged, the undetermined short axis is updated in an iterative manner by using the preset target step length, and the updated undetermined short axis is obtained by combining the intermediate ratio.

And S246, jumping and executing the step of combining the undetermined long shaft with the intermediate ratio and calculating to obtain the undetermined short shaft.

In the embodiment of the invention, the step of combining the undetermined long axis with the intermediate ratio to obtain the undetermined short axis by calculation is skipped, the new undetermined long axis and the undetermined short axis are combined with the target center coordinate and the target inclination angle to fit the ellipse, the preset energy calculation formula is adopted to obtain a new ellipse energy value by calculation, the ellipse energy value is compared with the energy value of the region of interest again to obtain a new energy ratio, and the step is repeatedly updated in an iterative manner.

And S247, when the energy ratio is in a preset energy ratio range, determining the undetermined long shaft at the current moment as a target long shaft, and determining the undetermined short shaft at the current moment as a target short shaft.

In the embodiment of the invention, the preset energy ratio condition is a preset energy ratio range, the long axis to be determined and the short axis to be determined are combined with the intermediate ratio for iterative updating, and the target central coordinate, the target inclination angle and the preset energy calculation formula are combined for calculation to obtain a new ellipse energy value. And when the energy ratio is in a preset energy ratio range, the undetermined long shaft at the current moment is taken as a target long shaft, and the undetermined short shaft at the current moment is taken as a target short shaft, so that the long shaft and the short shaft of the light spot in the light spot image are obtained.

And step 205, fitting an ellipse by adopting the target long axis, the target short axis, the target center coordinate and the target inclination angle, and determining the light spot parameters corresponding to the light spot image.

In the embodiment of the invention, an ellipse is fitted on the light spot image by using the target long axis, the target short axis, the target center coordinate and the target inclination angle, the light spot gray scale image is subjected to pseudo-colorization display by combining a set pseudo-color table to obtain the energy distribution of the light spot, and the light spot parameters such as the shape, the size, the center coordinate, the energy distribution and the like of the light spot in the light spot image are determined.

In the embodiment of the invention, firstly, the background gray level mean value in the light spot image is calculated by an elliptical ring, and the gray value coordinate without the influence of the background gray value is obtained by combining the difference calculation. And carrying out aperture attenuation on the annular aperture by using a preset attenuation value, combining a maximum gray value coordinate in the gray value coordinates and a preset statistical moment formula to obtain a center coordinate and an inclination angle which are updated iteratively, and determining a target center coordinate and a target inclination angle when the center coordinate and the inclination angle are converged. And secondly, iteratively updating the initial long axis and the preset initial short axis by using a preset initial step length, calculating by using a gray value coordinate, a target center coordinate and a target inclination angle in combination with an elliptical circular convolution kernel formula, and determining the middle long axis and the middle short axis by using the minimum Euclidean distance when the initial short axis is larger than the initial long axis. The ratio of the middle major axis to the middle minor axis yields the middle ratio. And calculating by combining the intermediate ratio with a long shaft statistical moment formula to obtain the long shaft to be determined. And iteratively updating the undetermined long axis according to a preset target step length, and determining the target long axis and the target short axis when the energy ratio of the ellipse energy value and the interested region energy value is in a preset energy ratio range. And fitting an ellipse by adopting the target long axis, the target short axis, the target center coordinate and the target inclination angle to determine the light spot edge and energy distribution in the light spot image. The method solves the technical problems that the existing laser spot measurement method has high requirements on the selection of the size of an interested area and the change of ambient background light, the structure to be set is complex, and the robustness is poor.

Referring to fig. 3, fig. 3 is a block flow diagram illustrating an implementation process of a laser spot monitoring method based on annular filtering according to a third embodiment of the present invention;

step 1: collecting light spot images of various environment background lights.

And 2, step: and calculating the background gray average value in the light spot image by using the elliptical ring, and performing difference with the light spot image to obtain the light spot image with the background gray value removed.

And step 3: and (4) determining the ROI of the spot image with the background gray value removed in the step (2) (see fig. 4).

(1) And calculating the maximum value and the minimum value of the initial distance between the maximum gray value coordinate and the initial annular aperture, taking the maximum gray value as the center in the light spot image, and selecting an initial ROI area by combining the maximum value and the minimum value of the initial distance.

(2) And calculating the central coordinates (x, y) and the inclination angle theta by adopting a preset statistical moment formula according to the gray scale information in the initial ROI.

(3) And calculating the maximum distance and the minimum distance between the central coordinate (x, y) and the attenuation ring-shaped aperture, and updating the ROI area by combining the maximum distance and the minimum distance with the central coordinate (x, y).

(4) And (5) repeating the iterative calculation (2-3) until the central coordinate (x, y) and the inclination angle theta are converged, and finally determining the target ROI area to obtain the target central coordinate and the target inclination angle.

And 4, step 4: calculating the length from the target center coordinate to p% of the maximum gray scale value in step 3 as the initial length a of the initial long axis a1, calculating the length from the target center coordinate to q% of the maximum gray scale value as the set length L, and initializing the initial short axis b1, i.e., the initial length b =1 of the initial short axis b 1.

And 5: initial ratio r1= a1/b1 was calculated.

Step 6: fitting an ellipse after performing elliptical circular convolution filtering with the obtained target center coordinates, target tilt angle, initial major axis a1 and initial minor axis b1 (see fig. 5).

(1) Enabling an initial long axis a1= a and an initial short axis b1= b, generating an elliptical circular convolution kernel according to the target center coordinate, the target inclination angle, the initial long axis a1 and the initial short axis b1, and performing convolution and averaging at corresponding positions of a spot diagram to obtain an elliptical circular convolution feature M;

(2) updating the initial long axis a1 with the step size ta and updating the initial short axis b1 by the initial ratio r1 in the step 5 to generate a concentric elliptical circular convolution kernel;

(3) and (5) repeating the iteration step 6 (1-2), calculating the characteristic M of different convolution kernels under the same ratio, and stopping the iteration if the long axis a1> L.

(4) Representing feature similarity by calculating Euclidean distances S between different convolution kernel features M and standard light spot features under the same initial ratio r 1;

(5) the initial major axis a1= a is reset and the initial minor axis b1 is incremented by the step tb.

(6) And (5) repeating the iteration step (5) and the step (6) (1-5), obtaining the Euclidean distance S between the different convolution kernel characteristics M corresponding to each initial ratio r and the standard light spot characteristics, and stopping the iteration if b1 is more than or equal to a 1.

And 7: outputting the minimum Euclidean distance S in the step 6, taking the initial long axis a1 corresponding to the minimum Euclidean distance S as the intermediate long axis a2, taking the initial short axis b1 corresponding to the minimum Euclidean distance S as the intermediate short axis b2, and outputting an intermediate long axis a2 and an intermediate long axis b 2; the intermediate ratio r2= a2/b2 is calculated.

And 8: and (4) calculating the undetermined long axis a3 by using a long axis statistical moment formula.

And step 9: fixing the intermediate ratio r2 obtained in the step 7, and taking the undetermined long shaft a3 obtained in the step 8 as an undetermined long shaft;

(1) updating the undetermined short shaft b3= a3/r2 according to the intermediate ratio r2 and the undetermined long shaft a 3;

(2) fitting an ellipse by combining the target center coordinate and the target inclination angle, displaying the fitted ellipse on the light spot image, and calculating an energy value E1 inside the ellipse;

due to the power (or energy) density distribution over the laser beam cross-section: proportional to the square of the amplitude modulus of the laser beam:

thus, the elliptical energy valueE1：

Wherein,

is the gray value of the corresponding ellipse at z.

In the same way, the gray value in the ROI is substituted into the formula to obtain the energy value of the ROIE2。

(3) Calculating an energy value of the ROI areaE2, calculating the energy ratio of the ellipse to the ROI areaE=E1/E2；

(4) Updating the undetermined long axis a3 by taking the step length as t;

(5) repeating iteration steps 9 (1-4) until the energy ratioEAnd determining a target long axis, a target short axis and an ellipse within a preset energy proportion range.

Step 10: output energy ratio in step 9EAnd light spot parameters such as target center coordinates and inclination angles, and the edge and the center of the light spot detected by the target long axis, the target short axis and the target center coordinates correspondingly.

Step 11: and performing pseudo-color display on the ellipse on the spot image according to the set pseudo-color table (see fig. 6) to obtain the energy distribution level of the spot image.

In the embodiment of the invention, according to the statistical characteristics of the signals, the central coordinate and the inclination angle of the gray scale information of the optical spot image are calculated by using a preset statistical moment formula, and the position of the ROI area is determined. And finally determining the target ROI area by iteratively updating the ROI area and counting the stability of the central coordinate and the inclination angle to obtain the target central coordinate and the target inclination angle. And then combining the Gaussian distribution characteristics of the light spots, carrying out elliptical circular convolution filtering on the light spots, selecting an elliptical circular convolution kernel with the maximum similarity to determine the ratio of the major axis to the minor axis of the light spots, finally fitting the ellipse by using related parameters, calculating the energy ratio to obtain the major axis, the minor axis and the ellipse of the target, and combining the central coordinate of the target and the inclination angle of the target to further determine the edges of the light spots. The method solves the technical problems that the existing laser spot measurement method has high requirements on the selection of the size of an interested area and the change of ambient background light, the required structure is complex, and the robustness is poor, and can improve the measurement precision and robustness of spot parameters according to the statistical information of the spot gray value and the Gaussian distribution characteristics of spots.

Referring to fig. 7, fig. 7 is a block diagram illustrating a structure of a laser spot monitoring system based on annular filtering according to a fourth embodiment of the present invention;

the invention provides a laser spot monitoring system based on annular filtering, which comprises:

a central coordinate and inclination angle determining module 401, configured to determine, when a light spot image corresponding to the target device is acquired, a target central coordinate and a target inclination angle according to a gray value coordinate acquired from the light spot image;

an initial long axis determining module 402, configured to determine an initial long axis according to the target center coordinate and the gray value coordinate;

a target major-minor axis determining module 403, configured to iteratively update the initial major axis and a preset initial minor axis according to the gray value coordinate, the target center coordinate, and the target inclination angle, and determine a target major axis and a target minor axis;

and a light spot parameter determining module 404, configured to fit an ellipse with the target long axis, the target short axis, the target center coordinate, and the target inclination angle, and determine a light spot parameter corresponding to the light spot image.

Optionally, the center coordinate and tilt angle determination module 401 comprises:

and the background gray average value determining module is used for calculating the background gray average value in the light spot image in an elliptical ring shape when the light spot image corresponding to the target equipment is acquired.

And the gray value coordinate determination module is used for performing differential calculation on the spot image by adopting a background gray average value to obtain a gray value coordinate.

And the initial annular aperture building module is used for building the initial annular aperture by taking the maximum gray value coordinate in the gray value coordinates as the center and combining the preset long and short axis parameters.

And the initial distance determining module is used for calculating the maximum value and the minimum value of the initial distance from the maximum gray value coordinate to the initial annular diaphragm.

And the initial interested region determining module is used for initializing the interested region by taking the maximum gray value coordinate as the center of the interested region and combining the maximum value of the initial distance and the minimum value of the initial distance.

And the central coordinate inclination angle calculation module is used for respectively calculating the central coordinate and the inclination angle corresponding to the region of interest by adopting the gray information in the region of interest and combining a preset statistical moment formula.

And the target center coordinate inclination angle determining module is used for iteratively updating the center coordinate and the inclination angle based on the aperture attenuation result of the initial annular aperture, and determining the target center coordinate and the target inclination angle.

Further, the target center coordinate tilt angle determination module may further perform the steps of:

calculating the maximum value and the minimum value of the distance from the center coordinate to the attenuation ring-shaped aperture;

updating the initial annular aperture to an attenuation annular aperture, skipping to execute the step of respectively calculating the central coordinate and the inclination angle corresponding to the region of interest by adopting the gray scale information in the region of interest and combining a preset statistical moment formula;

when the center coordinates and the tilt angle converge, the center coordinates at the current time are determined as target center coordinates, and the tilt angle at the current time is determined as a target tilt angle.

Optionally, the initial long axis determining module 402 includes:

and the length determining module is used for calculating the length between the target center coordinate and the maximum value of the gray value coordinate.

And the initial long axis determining module is used for calculating the length by adopting a first preset percentage value to determine the initial long axis.

Optionally, the target long and short axis determining module 403 includes:

and the middle long and short axis determining module is used for iteratively updating the initial long axis and the preset initial short axis according to the gray value coordinate, the target center coordinate, the target inclination angle and the preset initial step length until the initial short axis is larger than or equal to the initial long axis, and obtaining the middle long axis and the middle short axis.

Further, the middle major and minor axis determination module may further perform the following steps:

calculating the length between the target center coordinate and the maximum value of the gray value coordinate and combining the length with a second preset percentage value to obtain a set length;

calculating an initial ratio between an initial long axis and a preset initial short axis;

according to the initial ratio, the target center coordinate, the target inclination angle and the first initial step length, carrying out iterative updating on the initial long axis and the initial short axis, and generating an elliptical annular convolution characteristic;

when the initial long axis is larger than the set length, calculating the Euclidean distance between each elliptic annular convolution characteristic and the standard light spot characteristic;

resetting the initial long axis, and iteratively updating the initial short axis by combining a second initial step length to obtain a new initial ratio;

performing jump execution according to the initial ratio, the target center coordinate, the target inclination angle and the first initial step length, performing iterative update on the initial long axis and the initial short axis, and generating an elliptical circular convolution characteristic;

and when the initial short axis is larger than the initial long axis, determining the middle long axis and the middle short axis according to the minimum Euclidean distance.

It is worth mentioning that the step of iteratively updating the initial major axis and the initial minor axis according to the initial ratio, the target center coordinate, the target tilt angle and the first initial step size, and generating the elliptical circular convolution feature further includes the steps of:

calculating to obtain an elliptical annular convolution kernel by adopting an initial long axis, an initial short axis, a target center coordinate and a target inclination angle;

calculating the convolution and average of the elliptical circular convolution kernels to obtain elliptical circular convolution characteristics;

updating an initial short axis by a first initial step size, and updating an initial long axis by combining an initial ratio;

and skipping execution adopts the initial long axis, the initial short axis, the target center coordinate and the target inclination angle to calculate and obtain the elliptical annular convolution kernel.

And the middle ratio calculation module is used for calculating the middle ratio of the middle long axis to the middle short axis.

And the undetermined long shaft calculation module is used for calculating the undetermined long shaft by adopting a long shaft statistical moment formula according to the intermediate ratio, the target center coordinate and the target inclination angle.

And the target long and short axis determination module is used for iteratively updating the undetermined long axis according to a preset target step length until the undetermined long axis meets a preset energy ratio condition, and determining the target long axis and the target short axis by adopting the undetermined long axis and the intermediate ratio.

Further, the target long and short axis determination module further comprises the following steps:

calculating the energy value of the region of interest by combining the intermediate ratio, the target center coordinate and the target inclination angle with a preset energy formula;

combining the undetermined long shaft with the intermediate ratio to calculate and obtain an undetermined short shaft;

calculating an ellipse energy value by combining a long axis to be determined, a short axis to be determined, a target center coordinate and a target inclination angle with a preset energy calculation formula;

calculating the energy ratio of the elliptical energy value and the energy value of the region of interest;

skipping and executing the step of combining the undetermined long shaft with the intermediate ratio and calculating to obtain an undetermined short shaft;

In the embodiment of the invention, when the light spot image corresponding to the target equipment is acquired, the target center coordinate and the target inclination angle are determined according to the gray value coordinate acquired from the light spot image, and the initial long axis is determined based on the distance relationship between the target center coordinate and the gray value coordinate. And according to the gray value coordinate, the target center coordinate and the target inclination angle, performing iterative updating on the initial long axis and a preset initial short axis to determine the target long axis and the target short axis. And finally, fitting an ellipse by adopting the target long axis, the target short axis, the target center coordinate and the target inclination angle to obtain the light spot parameters corresponding to the light spot image. The method solves the technical problems that the existing laser spot measurement method has high requirements on the selection of the size of an interested area and the change of ambient background light, the required structure is complex, and the robustness is poor, and can improve the measurement precision and robustness of spot parameters according to the statistical information of the spot gray value and the Gaussian distribution characteristics of spots.

Referring to fig. 8, fig. 8 is a block diagram illustrating an electronic device according to an embodiment of the invention.

An electronic device according to an embodiment of the present invention includes: a memory 502 and a processor 501, wherein the memory 502 stores a computer program, and when the computer program is executed by the processor 501, the processor 501 executes the laser spot monitoring method based on annular filtering according to any of the above embodiments.

The memory 502 may be an electronic memory such as a flash memory, an EEPROM (electrically erasable programmable read only memory), an EPROM, a hard disk, or a ROM. The memory 502 has a memory space 503 for program code 513 for performing the steps of the method according to the invention. For example, the storage space 503 for program code may comprise respective program code 513 for implementing the various steps in the above method, respectively. The program code can be read from or written to one or more computer program products. These computer program products comprise a program code carrier such as a hard disk, a Compact Disc (CD), a memory card or a floppy disk. The program code may be compressed, for example, in a suitable form. The code, when executed by a computing processing device, causes the computing processing device to perform the steps of the method described above.

It can be clearly understood by those skilled in the art that, for convenience and brevity of description, the specific working processes of the method, the system and the device described above may refer to corresponding processes in the foregoing method embodiments, and are not described herein again.

In the several embodiments provided in this application, it should be understood that the disclosed method, system, and apparatus may be implemented in other ways. For example, the above-described apparatus embodiments are merely illustrative, and for example, a division of a unit is merely a logical division, and an actual implementation may have another division, for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may be in an electrical, mechanical or other form.

The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one position, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment.

In addition, functional units in the embodiments of the present invention may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit. The integrated unit can be realized in a form of hardware, and can also be realized in a form of a software functional unit.

The integrated unit, if implemented in the form of a software functional unit and sold or used as a stand-alone product, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present invention, which is substantially or partly contributed by the prior art, or all or part of the technical solution may be embodied in a software product, which is stored in a storage medium and includes instructions for causing a computer device (which may be a personal computer, a server, or a network device) to perform all or part of the steps of the method according to the embodiments of the present invention. And the aforementioned storage medium includes: a U-disk, a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk or an optical disk, and other various media capable of storing program codes.

The above-mentioned embodiments are only used for illustrating the technical solutions of the present invention, and not for limiting the same; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.

Claims

1. A laser spot monitoring method based on annular filtering is characterized by comprising the following steps:

according to the gray value coordinate, the target center coordinate and the target inclination angle, performing iterative updating on the initial long axis and a preset initial short axis to determine a target long axis and a target short axis;

2. The laser spot monitoring method based on annular filtering as claimed in claim 1, wherein the step of determining a target center coordinate and a target tilt angle according to a gray value coordinate obtained from the spot image when the spot image corresponding to the target device is acquired comprises:

taking the maximum gray value coordinate as the center of the region of interest, and combining the maximum initial distance value and the minimum initial distance value to initialize the region of interest;

3. The annular filtering based laser spot monitoring method of claim 2, wherein the step of iteratively updating the center coordinates and the tilt angle based on the aperture attenuation result for the initial annular aperture to determine target center coordinates and target tilt angle comprises:

4. The annular filtering-based laser spot monitoring method according to claim 1, wherein the step of determining an initial long axis according to the target center coordinates and the gray value coordinates comprises:

5. The method for monitoring laser spots based on ring filtering as claimed in claim 1, wherein the step of iteratively updating the initial major axis and the preset initial minor axis according to the gray value coordinates, the target center coordinates and the target tilt angle to determine a target major axis and a target minor axis comprises:

6. The method for monitoring laser spots based on ring filtering according to claim 5, wherein the step of iteratively updating the initial major axis and the preset initial minor axis according to the gray value coordinates, the target center coordinates, the target tilt angle and a preset initial step size until the initial minor axis is greater than or equal to the initial major axis to obtain a middle major axis and a middle minor axis comprises:

when the initial long axis is larger than the set length, calculating the Euclidean distance between each elliptic annular convolution feature and a standard light spot feature;

skipping to execute the step of performing iterative update on the initial long axis and the initial short axis according to the initial ratio, the target center coordinate, the target inclination angle and a first initial step length, and generating an elliptical circular convolution characteristic;

7. The ring filter-based laser spot monitoring method of claim 6, wherein the step of iteratively updating the initial major axis and the initial minor axis according to the initial ratio, the target center coordinate, the target tilt angle, and a first initial step size, and generating an elliptical ring convolution feature comprises:

8. The annular filtering-based laser spot monitoring method according to claim 5, wherein the preset energy ratio condition is a preset energy ratio range; the step of determining the target long axis and the target short axis by adopting the undetermined long axis and the intermediate ratio when the undetermined long axis is iteratively updated according to a preset target step length until the undetermined long axis meets a preset energy ratio condition comprises the following steps:

9. A laser spot monitoring system based on annular filtering, comprising:

the target long and short axis determining module is used for iteratively updating the initial long axis and a preset initial short axis according to the gray value coordinate, the target center coordinate and the target inclination angle, and determining a target long axis and a target short axis;

10. An electronic device, comprising a memory and a processor, wherein the memory stores a computer program, and the computer program, when executed by the processor, causes the processor to perform the steps of the method for ring filter based laser spot monitoring according to any one of claims 1-8.