CN111582187A - Automatic meter reading method based on mixed Gaussian background modeling - Google Patents

Automatic meter reading method based on mixed Gaussian background modeling Download PDF

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CN111582187A
CN111582187A CN202010393108.7A CN202010393108A CN111582187A CN 111582187 A CN111582187 A CN 111582187A CN 202010393108 A CN202010393108 A CN 202010393108A CN 111582187 A CN111582187 A CN 111582187A
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reading
pointer
background modeling
mixed gaussian
instrument
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罗艺
袁齐坤
王学良
晏凯
尤志鹏
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Kunming Enersun Technology Co Ltd
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    • G06COMPUTING; CALCULATING OR COUNTING
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    • G06V20/10Terrestrial scenes
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    • G06COMPUTING; CALCULATING OR COUNTING
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    • G06T7/277Analysis of motion involving stochastic approaches, e.g. using Kalman filters
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    • G06TIMAGE DATA PROCESSING OR GENERATION, IN GENERAL
    • G06T2207/00Indexing scheme for image analysis or image enhancement
    • G06T2207/30Subject of image; Context of image processing
    • G06T2207/30108Industrial image inspection
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    • G06COMPUTING; CALCULATING OR COUNTING
    • G06TIMAGE DATA PROCESSING OR GENERATION, IN GENERAL
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    • G06T2207/30241Trajectory
    • GPHYSICS
    • G06COMPUTING; CALCULATING OR COUNTING
    • G06VIMAGE OR VIDEO RECOGNITION OR UNDERSTANDING
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    • G06V2201/02Recognising information on displays, dials, clocks

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Abstract

The invention discloses an automatic meter reading method based on mixed Gaussian background modeling, which is used for recording data of various meters in the operation process of a power grid system and obtaining a scheduling basis for ensuring the safe and stable operation of the whole power grid system on the basis of analyzing the data. The method adopts the camera to acquire the video data of the instrument panel and preprocesses the data; performing background modeling on the instrument panel by using mixed Gaussian background modeling, and extracting a pointer area of the instrument by using a background difference technology; tracking and filtering the pointer target with wrong adjustment by using a kalman filter to the candidate pointer area; and calculating the current reading of the instrument according to the position of the pointer in the instrument panel. The invention can realize automatic reading of the pointer instrument of the power grid equipment, can simultaneously realize reading of a plurality of dials, has the operation efficiency meeting the real-time requirement, effectively reduces the dependence of panel board patrol on manual work, and greatly improves the efficiency and the accuracy of the panel board patrol process.

Description

Automatic meter reading method based on mixed Gaussian background modeling
Technical Field
The invention relates to an automatic meter reading method based on mixed Gaussian background modeling, and belongs to the technical field of power dispatching automation.
Background
In the period of the complete development of industrialization in China, various non-renewable resources are gradually exhausted, and various renewable resources are urgently needed to be developed; in addition, the dependence of each industry on electric power resources is gradually increasing with the progress of industrialization. Renewable electric resources (such as water resources, wind resources and solar resources) in China are mainly and intensively distributed in the middle and western regions, economically developed regions are intensively distributed in the eastern coastal regions, and the situation that the electric resources and the economic development are not uniformly distributed needs to be broken through, and the situation that the electric resources and the economic development are only distributed by using a large-capacity long-distance power transmission system can be realized. The adoption of high-voltage and ultrahigh-voltage power transmission systems is a main mode for realizing long-distance transmission of electric power energy. After the ultrahigh-voltage high-capacity power transmission line is greatly expanded, the maintenance of safe and stable operation of the ultrahigh-voltage power transmission line is a solid foundation for high-speed increase of economic construction in China, and the high-quality high-frequency inspection operation and maintenance is a necessary condition for ensuring stable operation of a large-scale power transmission system. The manual inspection is easily affected by factors such as terrain, personnel and weather, so that the inspection efficiency is low, the inspection effect is poor, the real-time performance is poor, and the manual inspection maintenance mode cannot meet the requirement of power utility development in a new era. A large number of pointer type instruments are installed on various devices in a power grid system, and the running states of power devices are detected through data of the instruments, so that safe and stable running of the power grid system is scheduled and controlled. Compared with a digital instrument, the pointer instrument has the characteristics of low price, simple structure, electromagnetic interference resistance, long service life and the like, and can adapt to various complex electromagnetic interference environments in a power grid system for a long time. At present, reading of equipment and meters in a power grid system mainly depends on a manual mode, the equipment in the power grid system is various, the quantity of the meters is large, the labor intensity of manual reading is high, and the precision and the efficiency of the manual reading can be gradually reduced along with the lapse of working time. In addition, in some places with electricity, high voltage and high temperature, the manual reading mode cannot be used by means of intelligent identification.
Disclosure of Invention
A meter automatic reading method based on mixed Gaussian background modeling comprises the following steps:
1. image preprocessing and denoising;
2. modeling a mixed Gaussian background;
3. kalman filtering tracking;
4. and (4) calculating the reading of the meter.
Further, the present invention comprises:
1) image pre-processing denoising
The harmonic mean filtering processing can be used for effectively reducing noise. Specifically, the gaussian template filtering employed is as follows:
Figure BDA0002486357900000021
we generate a two-dimensional convolution template by discretizing a two-dimensional gaussian function, typically using a size of 3 x 3. The gaussian template of 3 x 3 is shown below:
Figure BDA0002486357900000022
2) gaussian mixture background modeling
Normal distribution (Normal distribution) is a very important probability distribution in the fields of mathematics, physics, engineering, etc., and has a great influence on many aspects of statistics. If the random variable X obeys a mathematical expectation of mu and the standard deviation of sigma2Is recorded as:
X~N(μ,σ2);
the probability density function is then:
Figure BDA0002486357900000023
the expected value μ of a normal distribution determines its position and the standard deviation σ determines the amplitude of the distribution. Modeling is carried out on each pixel point in the image by adopting 3-5 normal distributions, and the states of the pixel points are represented by the weighted summation of the Gaussian distributions, so that the condition that the image background has a plurality of states can be well described, for example, the scene has periodic light change. The mathematical description is shown below. W hereinjIs the mean of the distribution, η (x; θ)j) Is the covariance matrix of the jth distribution, and x is the color [ R, G, B ] representing the pixel]A three-dimensional vector.
Figure BDA0002486357900000031
3) Kalman filter tracking
The Kalman filter algorithm, which describes an efficient linear measurement update on the estimate and error variance, can be divided into two parts:
3.1 time update (prediction) equation, as shown in the following equation.
Figure BDA0002486357900000032
Figure BDA0002486357900000033
3.2 measure the update equation, as shown in the following equation.
Kk=Pk -HT(HPk -HT+R)-1
Figure BDA0002486357900000034
Pk=(I-KkH)Pk -
The motion of the pointer in the instrument panel is uniform circular motion, and the pointer is variable speed motion from the speed perspective, and belongs to a nonlinear system; however, circular motion is a uniform motion in terms of angular velocity of circular motion, and belongs to a linear system, and we can describe the system by a formula, namely a state transition equation of the system, wherein ω is angular velocity, R is radius, and v is linear velocity.
ωk+1=ωk
vk+1=R*ωk+1
4) Meter reading calculation
In the process of using the hybrid Gaussian background modeling difference to detect the pointer of the instrument panel of the electric equipment, the image background of the instrument panel is changed greatly due to the complex environment of the pointer of the instrument panel, and for example, light changes, moving objects, floating objects and the like can be detected as candidate pointer areas. The motion state of the pointer of the instrument is described by using circular motion and tracked by using a Kalman filter to obtain the track of each candidate pointer target, if the current point of one track coincides with the starting point on a time sequence, the current pointer target is considered to be found, and the current reading value of the instrument is calculated by using the following formula, wherein value is the current reading of the table, valuemax is the maximum measurement of the table, and ω 0, ω 1 and ω max respectively represent the angle of the starting position of the pointer, the angle of the current position and the angle corresponding to the maximum measurement range.
Figure BDA0002486357900000041
The invention has the advantages of
The invention provides an automatic meter reading method based on mixed Gaussian background modeling, which comprises the steps of acquiring real-time video data of a meter panel through a network camera, performing Gaussian smoothing on a video image to remove Gaussian noise in the image, reconstructing a background image of the meter panel by adopting the mixed Gaussian background modeling method, extracting a pointer area through a background difference algorithm, performing Kalman filtering tracking on the pointer area to obtain a motion track of a pointer on the meter panel, determining a real pointer object through the circumferential characteristic of the track, and finally calculating the real-time reading of the meter panel. The algorithm of the invention can realize automatic reading of the pointer instrument of the power grid equipment, can simultaneously realize reading of a plurality of dials, has the operation efficiency meeting the real-time requirement, effectively reduces the dependence of panel board patrol on manual work, and greatly improves the efficiency and accuracy of the panel board patrol process.
Drawings
FIG. 1 is a flow chart of the method for automatic reading of a mixed Gaussian background modeling meter of the present invention.
Detailed Description
Referring to fig. 1, one embodiment of the present invention is:
1) image pre-processing denoising
Since the image is disturbed by various noises during the generation, transmission and recording processes, noise reduction is a very important step before further performing the operations of feature extraction, object recognition, etc. In the process of aerial photography, due to the influence of imaging equipment in the environment, light, electricity and other factors, the acquired image contains impulse noise. Meanwhile, due to the influence of random factors such as smoke, fog, wind, cloud and the like, the imaging viewpoint changes complexly, so that Gaussian noise exists in the acquired image inevitably. Gaussian noise is a random noise, which refers to noise whose n-dimensional distribution obeys gaussian distribution. Because gaussian noise is very well processed in both the spatial and frequency domains, its model is commonly used in practice. The harmonic mean filter reduces sharp transition of image gradation by averaging pixels in the neighborhood of the filter. The gaussian noise is caused by the sharp transformation of the gray scale, so that the harmonic mean filtering processing can be used for effectively reducing the noise. By the image preprocessing technology, the contrast and the quality of the image are greatly improved, the image characteristics of the research object can be more obvious, and the fault defect identification is facilitated. The gaussian template filtering is as follows:
Figure BDA0002486357900000051
we generate a two-dimensional convolution template by discretizing a two-dimensional gaussian function, typically using a size of 3 x 3. The gaussian template of 3 x 3 is shown below:
Figure BDA0002486357900000052
2) gaussian mixture background modeling
The basis of video object analysis is to separate the object region of interest from the scene, and the common separation methods are motion segmentation and background differentiation. The typical motion segmentation is to assume a constant background image in time series, and to demarcate a difference part between the background image and the current image by a threshold value. This method is relatively fast and easy to implement in many applications, but problems arise when tracking multiple targets or when a target suddenly stops. Due to the inherent drawbacks of motion detection based on frame differences, one has turned the direction of research to background differences, although the temporal complexity of the algorithm is increased when updating the background.
Normal distribution (Normal distribution) is a very important probability distribution in the fields of mathematics, physics, engineering, etc., and has a great influence on many aspects of statistics. If the random variable X obeys a mathematical expectation of mu and the standard deviation of sigma2Is recorded as:
X~N(μ,σ2);
the probability density function is then:
Figure BDA0002486357900000053
the expected value μ of a normal distribution determines its position and the standard deviation σ determines the amplitude of the distribution. Modeling is carried out on each pixel point in the image by adopting 3-5 normal distributions, and the states of the pixel points are represented by weighted summation of Gaussian distributions, so that the existence of a plurality of states of the image background can be well describedSuch as the presence of periodic light changes in the scene. The mathematical description is shown below. W hereinjIs the mean of the distribution, η (x; θ)j) Is the covariance matrix of the jth distribution, and x is the color [ R, G, B ] representing the pixel]A three-dimensional vector.
Figure BDA0002486357900000061
3) Kalman filter tracking
Kalman filtering (Kalman filtering) is an algorithm that uses a linear system state equation to optimally estimate the state of a system by inputting and outputting observation data through the system. The optimal estimation can also be seen as a filtering process, since the observed data includes the effects of noise and interference in the system. Data filtering is a data processing technique for removing noise and restoring true data, and Kalman filtering can estimate the state of a dynamic system from a series of data with measurement noise under the condition that measurement variance is known. Kalamn filtering is the optimal solution to the problem of linear filtering of discrete data, and this filter can be derived in solving the optimal estimate of a linear system that is susceptible to white gaussian noise interference. The following system of equations may be used to determine a linear system given a discrete time process. The Kalman filter algorithm, which describes an efficient linear measurement update on the estimate and error variance, can be divided into two parts:
3.1 time update (prediction) equation, as shown in the following equation.
Figure BDA0002486357900000062
Figure BDA0002486357900000063
3.2 measure the update equation, as shown in the following equation.
Kk=Pk -HT(HPk -HT+R)-1
Figure BDA0002486357900000064
Pk=(I-KkH)Pk -
The motion of the pointer in the instrument panel is uniform circular motion, and the pointer is variable speed motion from the speed perspective, and belongs to a nonlinear system; however, circular motion is a uniform motion in terms of angular velocity of circular motion, and belongs to a linear system, and we can describe the system by a formula, namely a state transition equation of the system, wherein ω is angular velocity, R is radius, and v is linear velocity.
ωk+1=ωk
vk+1=R*ωk+1
4) Meter reading calculation
In the process of using the hybrid Gaussian background modeling difference to detect the pointer of the instrument panel of the electric equipment, the image background of the instrument panel is changed greatly due to the complex environment of the pointer of the instrument panel, and for example, light changes, moving objects, floating objects and the like can be detected as candidate pointer areas. The motion state of the pointer of the instrument is described by using circular motion and tracked by using a Kalman filter to obtain the track of each candidate pointer target, if the current point of one track coincides with the starting point on a time sequence, the current pointer target is considered to be found, and the current reading value of the instrument is calculated by using the following formula, wherein value is the current reading of the table, valuemax is the maximum measurement of the table, and ω 0, ω 1 and ω max respectively represent the angle of the starting position of the pointer, the angle of the current position and the angle corresponding to the maximum measurement range.
Figure BDA0002486357900000071

Claims (2)

1. A meter automatic reading method based on mixed Gaussian background modeling is characterized by comprising the following steps:
1) image preprocessing and denoising;
2) modeling a mixed Gaussian background;
3) kalman filtering tracking;
4) calculating the reading of the meter;
the 1) image preprocessing denoising comprises:
the harmonic mean filtering processing can be used for effectively reducing noise. Specifically, the gaussian template filtering employed is as follows:
Figure FDA0002486357890000011
by discretizing a two-dimensional gaussian function, a two-dimensional convolution template is generated, typically using a size of 3 x 3. The gaussian template of 3 x 3 is shown below:
Figure FDA0002486357890000012
the 2) mixed Gaussian background modeling comprises the following steps:
the normal distribution is noted as:
X~N(μ,σ2);
the probability density function is noted as:
Figure FDA0002486357890000013
modeling each pixel point in the image by normal distribution:
Figure FDA0002486357890000014
in the formula wjIs the mean of the distribution, η (x; θ)j) Is the covariance matrix of the jth distribution, and x is the color [ R, G, B ] representing the pixel]A three-dimensional vector;
the 3 Kalman filtering tracking comprises:
3.1) time update (prediction) equation:
Figure FDA0002486357890000021
Figure FDA0002486357890000022
3.2) measurement update equation:
Kk=Pk -HT(HPk -HT+R)-1
Figure FDA0002486357890000023
Pk=(I-KkH)Pk -
the state transition equation of the system:
ωk+1=ωk
vk+1=R*ωk+1
where ω is angular velocity, R is radius, and v is linear velocity.
2. The method for automatically reading a meter based on mixed Gaussian background modeling according to claim 1, characterized in that:
the 4) meter reading calculation comprises the following steps:
Figure FDA0002486357890000024
where value is the current reading of the table, value max is the maximum measurement of the table, and ω 0, ω 1, and ω max represent the angle of the start position of the pointer, the angle of the current position, and the angle corresponding to the maximum measurement range, respectively.
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Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102025981A (en) * 2010-12-23 2011-04-20 北京邮电大学 Method for detecting foreground in monitoring video
CN103134571A (en) * 2013-01-24 2013-06-05 宁波市计量测试研究院(宁波市衡器管理所) Water meter automatic verification technology based on dynamic video image processing and pattern recognition algorithm
CN103164692A (en) * 2012-12-03 2013-06-19 北京科技大学 Special vehicle instrument automatic identification system and algorithm based on computer vision
US20140232649A1 (en) * 2011-09-09 2014-08-21 Movea Method of controlling a cursor by measurements of the attitude of a pointer and pointer implementing said method
CN106529559A (en) * 2016-12-30 2017-03-22 山东鲁能软件技术有限公司 Pointer-type circular multi-dashboard real-time reading identification method
CN108960237A (en) * 2018-06-29 2018-12-07 上海海事大学 A kind of pointer type fuel level indicator Recognition of Reading method

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102025981A (en) * 2010-12-23 2011-04-20 北京邮电大学 Method for detecting foreground in monitoring video
US20140232649A1 (en) * 2011-09-09 2014-08-21 Movea Method of controlling a cursor by measurements of the attitude of a pointer and pointer implementing said method
CN103164692A (en) * 2012-12-03 2013-06-19 北京科技大学 Special vehicle instrument automatic identification system and algorithm based on computer vision
CN103134571A (en) * 2013-01-24 2013-06-05 宁波市计量测试研究院(宁波市衡器管理所) Water meter automatic verification technology based on dynamic video image processing and pattern recognition algorithm
CN106529559A (en) * 2016-12-30 2017-03-22 山东鲁能软件技术有限公司 Pointer-type circular multi-dashboard real-time reading identification method
CN108960237A (en) * 2018-06-29 2018-12-07 上海海事大学 A kind of pointer type fuel level indicator Recognition of Reading method

Non-Patent Citations (6)

* Cited by examiner, † Cited by third party
Title
伍健荣等: "一种基于Kalman滤波器的自适应背景建模改进算法", 《传感器与微系统》 *
刘伟等: "自适应混合高斯建模的高效运动目标检测", 《中国图象图形学报》 *
季建平等: "一种准确提取设备系统仪表指示的方法", 《仪表技术》 *
李学聪等: "指针式仪表图像的六步预处理方法", 《电测与仪表》 *
郭贵法等: "改进的同态滤波在指针式仪表图像预处理中的应用", 《广东工业大学学报》 *
黄超群: "基于混合高斯模型和kalman滤波器的运动目标检测与跟踪", 《中国优秀硕士学位论文全文数据库 信息科技辑》 *

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