CN103743452B - Contact-free level measures system - Google Patents
Contact-free level measures system Download PDFInfo
- Publication number
- CN103743452B CN103743452B CN201310751029.9A CN201310751029A CN103743452B CN 103743452 B CN103743452 B CN 103743452B CN 201310751029 A CN201310751029 A CN 201310751029A CN 103743452 B CN103743452 B CN 103743452B
- Authority
- CN
- China
- Prior art keywords
- point
- boundary line
- limit
- image
- liquid level
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Landscapes
- Image Analysis (AREA)
Abstract
The present invention relates to sensor and field of measuring technique, system is measured particularly to a kind of contact-free level, including the probe being arranged on fluid reservoir top, pop one's head in and the analogue video signal collected is exported to processing module, processing module includes image pick-up card, industrial computer or computer, analogue video signal is converted into digital image information, industrial computer or computer by described image pick-up card to carry out process and extracts liquid level boundary function and draw liquid level according to this function digital image information.In whole liquid level, the change on liquid level border is minimum, by gathering the image information of liquid level, liquid level distribution in border is simulated by equation, after the position of probe is fixing, the most just can draw liquid level by liquid level boundary function, even if liquid level exists drop, also can accurately record result；This system is applied widely, it is possible to measure in real time, is not affected by the factor such as surrounding, temperature.
Description
Technical field
The present invention relates to sensor and field of measuring technique, survey particularly to a kind of contact-free level
Amount system.
Background technology
At present the tank level automatic measurement application in the industry such as industrial, agriculture, medical is the widest
General, its Principle and method of measurement is numerous, whether contacts according to liquid, is divided into contact liquid level to survey
Amount and non-contact measurement two class.Contact have float type level gauge, pressure-type liquidometer etc.,
The liquidometer of contact is often because of factor impacts such as liquid itself, environment, and its precision can be gradually lowered,
Service life is the shortest, so that maintenance cost is higher.Contactless has ultrasonic type, thunder
Reaching waves, they calculate liquid by measuring the time difference launched between impulse wave and reception echo
Bit depth, their shortcoming is to be not suitable for level change to rock bigger occasion, otherwise reflection echo
It would be possible to do not receive, and installation accuracy must be accurate, and the measured deviation otherwise brought is very
It is difficult to greatly eliminate.Additionally, if measured liquid is band corrosivity or explosive, it measures process
Sensing device must be that anticorrosion is explosion-proof, and this result also in whole measurement apparatus cost increases, restriction
The process of numerous automatic fields.
For solving these problems, Chinese patent " a kind of level gauging limit method and device thereof " (application
Number: 200110023135.6；Publication date: on 01 26th, 2005) disclose following skill
Art limit case: the picture of selected measured zone H1 taken the photograph to obtain by imageing sensor, and exported by picture
Carry out process to computer and obtain liquid level.This scheme exists following not enough: 1, cannot be complete
Become the measurement of unstable liquid level；2, the object such as overcasting staff, coloured buoy and liquid need to be additionally set
Body contacts, and is not reaching to non-contact measurement truly；3, due to imageing sensor cloth
The mode of putting is limited so that the drop of measurement is less.
Summary of the invention
It is an object of the invention to provide a kind of contact-free level and measure system, it is possible to accurately measure
Liquid level information, and it is applicable to various extreme environment.
For realizing object above, the technology limit case that the present invention uses is: a kind of contact-free level is surveyed
Amount system, including being arranged on the probe of fluid reservoir top, the analogue video signal that probe will collect
Output is to processing module, and processing module includes image pick-up card, industrial computer or computer, described
Analogue video signal is converted into digital image information, industrial computer or computer logarithm by image pick-up card
Word image information carries out process and extracts liquid level boundary function and draw liquid level according to this function.
Compared with prior art, there is techniques below effect in the present invention: in whole liquid level, liquid level limit
The change on boundary is minimum, by gathering the image information of liquid level, liquid level distribution in border is entered by equation
By liquid level boundary function, row simulation, after the position of probe is fixing, the most just can show that liquid level is high
Degree, even if liquid level exists drop, also can accurately record result；In whole system, only Probe arrangement
In fluid reservoir, only need to select different probes, or do high temperature resistant, corrosion-resistant in probe outside
Process, just can meet the level monitoring under various environment, applied widely；It addition, by this survey
Amount system can measure in real time, is not affected by the factor such as surrounding, temperature.
Accompanying drawing explanation
Fig. 1 is the theory diagram of the present invention；
Fig. 2 is the image of processing procedure of the present invention, and wherein Fig. 2 a is original image, and artwork is color
Color, Fig. 2 b, 2c, 2d, 2e, 2f are the image after step A, B, C, D, E process, figure
Diagonal in 2f illustrates that step F1, not this dotted line on actual image；
Fig. 3 is the schematic diagram that the present invention searches longest edge boundary line.
Detailed description of the invention
Below in conjunction with Fig. 1 to Fig. 3, the present invention is described in further detail.
Refering to Fig. 1, a kind of contact-free level measures system, including being arranged on fluid reservoir top
Probe 10, the analogue video signal collected is exported to processing module 20, processes mould by probe 10
Block 20 includes image pick-up card 21, industrial computer or computer 22, described image pick-up card 21
Analogue video signal is converted into digital image information, industrial computer or computer 22 to digital picture
Information carries out process and extracts liquid level boundary function and draw liquid level according to this function.If inspection
Survey environment and there is high temperature highly corrosive, can use and there is high temperature resistant and corrosion resistance characteristic material protection
Video camera, utilizes water-cooled or air cooling to control camera environment temperature；If the environmental requirement of detection
The highest, then use general video camera.It addition, for the quality ensureing image, can be in storage
Installing high cold light illuminating lamp inside flow container additional, the installation site of light is the most critically important, its objective is to allow light
Source is radiated on measured target uniformly, reduces the complexity that successive image processes；For some not
Just use the occasion of light source, thermal camera can be used as probe 10.The selection of light source and layout
Position, the selection of probe are required for carrying out actual selection according to field condition, the most detailed
Thin narration.For the process of digital image information, industrial computer can be used, it is also possible to come with computer
Realizing, image is mainly processed by computer by the software run on it；Industrial computer is industry
With computer, it is more suitable for the place that site environment is the best.
The present invention is to judge the height of liquid level by extracting liquid level edge function, when probe 10
When position is fixed, if probe 10 is positioned at the surface of fluid reservoir, its liquid level edge letter obtained
Number should be circular, and diameter of a circle has relation one to one with the height of liquid level；If visiting
10 oblique uppers being positioned at fluid reservoir, its liquid level edge function obtained be oval, ellipse
Major axis, short axle, the height of central point and liquid level have relation one to one.We are by right
Liquid level edge function processes, it is thus achieved that important parameter, just can be according to the position of probe 10 layout
Calculate the height of liquid level.
Refering to Fig. 2, the acquisition of liquid level edge function has various ways, provides one the most excellent here
The embodiment of choosing: described digital image information is the image of BMP form, described industrial computer
Or computer 22 extracts a BMP image as original image as follows at set intervals
Process: (A) original image carries out gray processing process and obtains gray level image, wherein original image
As shown in Figure 2 a, gray level image is as shown in Figure 2 b；(B) gray level image carry out rectangular histogram conversion carry
The contrast of high gray level image, the image after rectangular histogram conversion is as shown in Figure 2 c；(C) step B
Image after process carries out binary conversion treatment according to certain threshold value, obtains black white image, artwork master
As shown in Figure 2 d；(D) black white image uses high pass filter to be filtered, and removes noise,
As shown in Figure 2 e；(E) continuum boundary is found out, each point coordinates in record longest edge boundary line, wherein
The longest boundary line is as shown in Fig. 2 f；(F) each point coordinates taking longest edge boundary line carries out equation
Immediate elliptic equation is found out in matching, or the partial dot coordinate taking longest edge boundary line carries out equation
Immediate parabolic equation is found out in matching；(G) join according to elliptic equation parameter or parabolic equation
Number determines liquid level.
Gray processing processing mode is various, as the preferred version of the present invention, in described step A,
Gray value f after original tristimulus value R, G, the B of any one pixel processes with gray processing is full
The relational expression that foot is following, gray value f=0.299R+0.587G+0.114B.Here, according to life
Human eye described in thing is different to the sensitivity of different colours, gives red R, green G, blue B respectively
Coefficients different in tax, the weighted mean then calculating them draw gray value f, so obtain
Image be more convenient for follow-up process.
Further, in described step B, by following transformation relation to pixel each in image
The gray value f of point carries out converting and obtains new gray value g: if 0≤f is ＜ a, then g=α f；If
A≤f ＜ b, then g=β (f-a)+ga；If b≤f≤255, then g=γ (f-b)+gb；Formula
Middle a, b, α, β, γ, ga、gbBeing constant, they have respective effect.A in formula,
B effect determines that the scope of three different grey-scales, the gray value of concentration of local amendment original image；
The effect of α, β, γ determines that the slope size of the function mapped when different grey-scale adjusts, instead
Scope and the degree of the change of gray scale linear segmented are reflected.The linear segmenting principle of gray scale is simple, uses spirit
Living, the image for different quality can freely determine Function Mapping relation, transformation range, pass through
The value of the tuned slope can stretch more than 1 or less than 1 in various degree or compress dividing of gray scale
Cloth is interval.
As the preferred version of the present invention, in order to follow-up liquid level border is easier to identify, take here
One suitable threshold value gxImage is carried out binary conversion treatment, in described step C, by 0≤g
≤gxPixel be filled to black and be labeled as 1, gxThe pixel of ＜ g≤255 is filled to white
And it being labeled as 0, described gx is the threshold value of binary conversion treatment.In image after process, each picture
Vegetarian refreshments or be black, or be white, data processing amount is little a lot.
In order to identify the marginal information of liquid level, provide one more preferably embodiment party here
Formula, carries out liquid level edge extracting by this step, and amount of calculation is much smaller, improves native system further
Real-time.In described step E, comprise the steps:
(E1) set up point of rejection set, first the point coordinates that color in image is black is stored to
In point of rejection set；If 8 points that certain point is the most adjacent have 6 or 7 black color dots, that
This point is stored to point of rejection set；Set up path point set for storing in closed sides boundary line
Each point coordinates, path point set starts as sky；
(E2) each pixel is judged successively by order from top to bottom, from left to right, if this point
Coordinate is not belonging to point of rejection set, is also not belonging to path point set, the most newly-built boundary line L,
Using this as the starting point of boundary line L, this point coordinates is stored in boundary line L set simultaneously,
Remember length X of boundary line L simultaneouslyN=1；After judging a little, enter step E10；
(E3) judge successively the limit, bottom right of starting point in step E2, the right, top right-hand side, on
Limit, limit, upper left, the left side, the point of left lower side, if seven points belong to point of rejection set or path point
Set, then store starting point to point of rejection set, and boundary line L set simultaneously empties, and repeats
Step E2 continues to judge from the next point of starting point；Otherwise using new point as boundary line L's
Second point coordinate stores in gathering to boundary line L, and records second point and be positioned at the direction of starting point,
With second point for searching point, enter step E4；
(E4) judge successively to search some consecutive points around,
If the former point searching point is positioned at the left side searching point, then press left lower side, following, limit, bottom right,
The right, top right-hand side, top, the order on limit, upper left are searched successively；
If the former point searching point is positioned at the left lower side searching point, then by below, limit, bottom right, the right,
Top right-hand side, top, limit, upper left, the order on the left side are searched successively；
If search point former point be positioned at search point following, then by limit, bottom right, the right, top right-hand side,
Top, limit, upper left, the left side, the order of left lower side are searched successively；
If search point former point be positioned at search point limit, bottom right, then by the right, top right-hand side, top,
Limit, upper left, the left side, left lower side, following order are searched successively；
If search point former point be positioned at search point the right, then press top right-hand side, top, limit, upper left,
The left side, left lower side, below, the order on limit, bottom right searches successively；
If search point former point be positioned at search point top right-hand side, then by top, limit, upper left, the left side,
Left lower side, below, limit, bottom right, the order on the right search successively；
If search point former point be positioned at search point top, then by limit, upper left, the left side, left lower side,
Below, limit, bottom right, the right, the order of top right-hand side are searched successively；
If the former point searching point is positioned at the limit, upper left searching point, then by the left side, left lower side, below,
Limit, bottom right, the right, top right-hand side, the order of top are searched successively；
(E5) if seven points belong to point of rejection set or path point set, then this search point is regarded
For the breakpoint of boundary line L, this search point coordinates is removed from boundary line L gathers, and this is searched
Seek point coordinates to store to point of rejection set, enter step E6；Otherwise, step E7 is entered；
(E6) if the previous point searching point is the starting point of boundary line L, then give up boundary line
L, repeats step E2 and continues to judge from the next point of starting point；Otherwise, to searching the previous of point
Individual step E4 of pressing around not judged continues to judge；
(E7) judge whether new point belongs in boundary line L set, the most then enter step E8；
If it is not, stored to by new point in boundary line L set, length XN of boundary line L adds 1,
The position relationship recording new point and search point, repeats step E4, step using new point as searching point
Rapid E5；
(E8) judge that whether new point is the starting point of boundary line L, the most then boundary line L searches
Seek end, obtain a new boundary line；If it is not, now the point set of boundary line L is combined into
{P0,P1..., PM-1,PM,PM+1,PM+2,…,PM+N, new point is PM, then by { PM,PM+1,…,PM+N}
As a new boundary line, simultaneously will a PM,PM+1,…,PM+NCoordinate remove from the L of boundary line,
Length X by boundary line LNDeduct the coordinate removed to count, then to a PM-1Around do not judge
Press step E4 to continue to judge；
(E9) often obtain a new boundary line, will be located in storing a little within this boundary line
To point of rejection set；This new boundary line length X is detected decision content X with constant simultaneouslyLCompare
Relatively, if X is ＜ XL, new boundary line is given up, new boundary line stores a little to point of rejection
In set, if X >=XL, new boundary line is preserved；
(E10) comparing the length of all boundary lines of storage, in output longest edge boundary line, each point is sat
Mark.
This step, is described in detail here by Fig. 3 for convenience of description, in Fig. 3 one
Little rectangle represents a pixel, and blank pixel represents white, fills the pixel position of oblique line
Black.For the ease of narration, below for any point, all calling is a some Xy, and wherein, X is for being somebody's turn to do
The columns at some place, y is the line number at this place.
It is first according to step E1, qualified point is stored to point of rejection set, its midpoint
Cd, some Dd, some Dh, some Eh also store to point of rejection set, and from figure, we can also be bright
Aobvious willing go out, these points belong to noise, and all of point of rejection enters step E2 after judging.Point
Ei is first and had both been not belonging to point of rejection set, the point being also not belonging in path point set, its conduct
Starting point is stored in the set of boundary line L, then, enters step E3.
First determining whether the some Fh on a limit, Ei bottom right, some Fh is point of rejection, continues to judge that some Ei is right
The point Fi on limit, some Fi is also point of rejection, continues to judge that some Fj, some Fj meet requirement, as
Second point stores in the set of boundary line L, now, does not continues to judge the point above some Ei
Ej, but next point will be searched with a Fj for searching point；
Owing to being positioned at the lower left of second point Fj from an Ei, during so searching with a Fj,
First judging the some Fi below some Fj, some Fi is point of rejection, continues to judge that some Gi, some Gi are also
Point of rejection, continues to judge some Gj, and some Gj meets requirement, as thirdly storage to boundary line L
Set in, the step for of repetition；
According to the step for search point collection be combined into: some Ei, put Fj, put Gj, put Hi, point
Ij, puts Ik, puts Jl, puts Kl, puts Ll, puts Ml, puts Nl, puts Ok, puts Oj, puts Oi,
Point Oh, puts Og, puts Of, puts Ne, puts Od, puts Pd, puts Qc, puts Rc, puts Sd, point
Te, puts Tf, puts Sg, puts Sh, puts Ri, puts Rj, puts Qj, puts Pj}, when continuing search for,
Next point is an Ok, has existed in above-mentioned set, now will be according in step E8
Mode processes, and set { is put Ok, puts Oj, put Oi, put Oh, put Og, some Of, point
Ne, puts Od, puts Pd, puts Qc, puts Rc, puts Sd, puts Te, puts Tf, puts Sg, puts Sh,
Point Ri, puts Rj, puts Qj, and some Pj} stores as a new boundary line, is denoted as here
First boundary line L1, its a length of X1, wherein each point all stores to path point set, meanwhile,
The institute that first boundary line L1 surrounds the most all is stored in point of rejection.
The search of boundary line L does not terminates, and returns to continue to search at a Nl, and some Nl is for the first time
During search, at an Ok, jump out search, but some Ok belongs in path point set now, therefore will
Continuing to judge some Ol, some Ol is point of rejection, continues to judge some Om, and some Om meets the requirements, and continues
Continuing and search with an Om, the rest may be inferred, can be gathered { some Ei, some Fj, some Gj, point
Hi, puts Ij, puts Ik, puts Jl, puts Kl, puts Ll, puts Ml, puts Nl, puts Om, puts Pm ...,
Point Fl, puts Fk}, and when continuing search for, next point is a Fj, is present in the collection of boundary line L
In conjunction, do same process according to step E8.Obtain the second boundary line L2, its collection be combined into some Fj,
Point Gj, puts Hi, puts Ij, puts Ik, puts Jl, puts Kl, puts Ll, puts Ml, puts Nl, point
Om, puts Pm ..., put Fl, put Fk}, its a length of X2, wherein each point all stores to road
In the some set of footpath, meanwhile, the institute that the second boundary line L2 surrounds the most all is stored to point of rejection
In.
The search of boundary line L, for terminating, returns to continue to search at an Ei, due to phase around Ei
Adjacent point or belong to point of rejection set, or belong to path point set, will be according to step E5, point
Ei is considered breakpoint, and some Ei is stored in point of rejection set, simultaneously enters step E6, due to
Point Ei is exactly starting point, so boundary line L abandons, repeats step E2, continues to judge some Ej.
As can be known from Fig. 3, follow-up point or be stored in point of rejection set, or it is stored in path point
In set, until having judged that last puts Vv, border is searched and is terminated.
It is pointed out that judgement to new boundary line length is not write into above, be because
Here only have the first boundary line, the second boundary line, it is assumed that their length both greater than detects decision content
XL.Now, enter step E10, compare the length of first and second boundary line, hence it is evident that the first border
Line length is less than the second boundary line length, stores each point coordinates of the second boundary line, enters step F.
The most why detection decision content X is setL, the boundary line length being because some new is less, hence it is evident that
It not the border that the present invention is to be looked for, can give up according to step E9.
As the preferred version of the present invention, described probe 10 is positioned at the oblique top of fluid reservoir and arranges,
In described step F, comprise the steps: that image is divided into by two diagonal of (F1) image
Four regions；(F2) each point coordinates in longest edge boundary line in the region that probe is farthest, and root are taken
Find out closest to the parabolic equation in longest edge boundary line in this region according to these coordinates.From probe 10
The delta-shaped region on the right in the i.e. Fig. 2 f of farthest region, on the one hand the benefit of do so is to reduce
Amount of calculation, on the other hand, will pop one's head in 10 diagonally disposed, in its image obtained, from probe 10
The image of most remote areas is very clear, improves the accuracy of result of determination, can be from Fig. 2 f
Going out, the boundary line on its left side is the most irregular.Owing to whole boundary line is similar to an ellipticity, because of
This, its curved section in 10 most remote areas of popping one's head in can fit to a parabolic equation.
Need exist for explanation, by Probe arrangement at fluid reservoir upper middle position, by liquid level
Boundary function uses the equation of circle to simulate also possible, but its degree of accuracy and amount of calculation all can
It is affected, parabolic equation in the present embodiment, is preferably used, use circle or ellipse to carry out simulated solution
Bit boundary function is also feasible.
Further, described parabolical general equation is: ((x-h) sin θ+(y-k) cos
θ)2=2p ((x-h) cos θ+(y-k) sin θ), wherein, θ is that parabola is by rotating counterclockwise
Angle, (h, k) is parabolical apex coordinate, and p is parabolical focal length；In described step G
The parameter of parabolic equation is i.e. (h, k, p, θ).Ginseng is solved by each point coordinates in longest edge boundary line
Number (h, k, p, θ) can be calculated by Hough transformation.Its detailed step is as follows:
In parameter space, create a 4-D add up array: hough_space (h, k, p, θ), when
When h, k, θ move on image in certain sequence, we just can calculate each parabola pair
Answer focal length p, and be shown below to hough_space (h, k, p, θ) is cumulative:
Ough_space (h, k, p, θ)=ough_space (h, k, p, θ)+1；
After completing traversal calculating, according to the result of cumulative rear hough space value, select accumulator
In hough_space, maximum just determines parabolical apex coordinate (h0, k0), anglec of rotation θ0
With focal length p0。
Further, owing to some site environment is more severe, optical fiber 33 is used to carry out here
The transmission of information: be provided with optical transmitter and receiver 30, light end between described probe 10 and image pick-up card 21
Machine 30 includes optical sender 31, photoreceiver 32, the input of optical sender 31 and probe 10
Outfan be connected, the outfan of photoreceiver 32 is connected with the input of image pick-up card 21,
Carried out data transmission by optical fiber 33 between optical sender 31 and photoreceiver 32.
Claims (7)
1. a contact-free level measures system, it is characterised in that: include being arranged on fluid reservoir
The probe (10) of top, the analogue video signal collected is exported to processing mould by probe (10)
Block (20), processing module (20) includes image pick-up card (21), computer (22), described
Image pick-up card (21) analogue video signal is converted into digital image information, computer (22)
Digital image information carries out process extract liquid level boundary function and draw liquid level according to this function
Highly；Described digital image information is the image of BMP form, described computer (22)
Extract a BMP image at set intervals to process as follows as original image:
(A) original image carries out gray processing process and obtains gray level image；
(B) gray level image carries out rectangular histogram conversion and improves the contrast of gray level image；
(C) image after step B processes carries out binary conversion treatment according to threshold value, obtains artwork master
Picture；
(D) black white image uses high pass filter to be filtered, and removes noise；
(E) continuum boundary is found out, each point coordinates in record longest edge boundary line；
(F) take each point coordinates in longest edge boundary line to carry out equation model and find out immediate ellipse side
Journey, or the partial dot coordinate taking longest edge boundary line carries out equation model and finds out immediate parabolic
Line equation；
(G) according to elliptic equation parameter or parabolic equation parameter determination liquid level；
In described step E, comprise the steps:
(E1) set up point of rejection set, first the point coordinates that color in image is black is stored
To point of rejection set；If 8 points that certain point is the most adjacent have 6 or 7 black color dots,
So this point is stored to point of rejection set；
Setting up path point set for storing each point coordinates in closed sides boundary line, path point collection is run jointly
Begin as sky；
(E2) each pixel is judged successively by order from top to bottom, from left to right, if should
Point coordinates is not belonging to point of rejection set, is also not belonging to path point set, the most newly-built boundary line
L, using this as the starting point of boundary line L, stores boundary line L by this point coordinates simultaneously
In set, remember length X of boundary line L simultaneouslyN=1；After judging a little, enter step
Rapid E10；
(E3) judge successively the limit, bottom right of starting point in step E2, the right, top right-hand side, on
Limit, limit, upper left, the left side, the point of left lower side, if seven points belong to point of rejection set or path
Point set, then store starting point to point of rejection set, and boundary line L set simultaneously empties,
Repeat step E2 to continue to judge from the next point of starting point；Otherwise using new point as boundary line
The second point coordinate of L stores in gathering to boundary line L, and records second point and be positioned at starting point
Direction, with second point for searching point, enters step E4；
(E4) judge successively to search some consecutive points around,
If the former point searching point is positioned at the left side searching point, then press left lower side, following, bottom right
Limit, the right, top right-hand side, top, the order on limit, upper left are searched successively；
If the former point of search point is positioned at the left lower side searching point, then by following, limit, bottom right, the right side
Limit, top right-hand side, top, limit, upper left, the order on the left side are searched successively；
If the former point searching point is positioned at searches the following of point, then by limit, bottom right, the right, upper right
Limit, top, limit, upper left, the left side, the order of left lower side are searched successively；
If search point former point be positioned at search point limit, bottom right, then by the right, top right-hand side, on
Limit, limit, upper left, the left side, left lower side, following order are searched successively；
If the former point searching point is positioned at the right searching point, then press top right-hand side, top, upper left
Limit, the left side, left lower side, below, the order on limit, bottom right searches successively；
If the former point searching point is positioned at the top right-hand side searching point, then by top, limit, upper left, a left side
Limit, left lower side, below, limit, bottom right, the order on the right search successively；
If the former point searching point is positioned at the top searching point, then by limit, upper left, the left side, lower-left
Limit, below, limit, bottom right, the right, the order of top right-hand side search successively；
If search point former point be positioned at search point limit, upper left, then by the left side, left lower side, under
Limit, limit, bottom right, the right, top right-hand side, the order of top are searched successively；
(E5) if seven points belong to point of rejection set or path point set, then by this search point
It is considered as the breakpoint of boundary line L, this search point coordinates is removed from boundary line L gathers, and will
This search point coordinates stores to point of rejection set, enters step E6；Otherwise, step E7 is entered；
(E6) if the previous point searching point is the starting point of boundary line L, then give up border
Line L, repeats step E2 and continues to judge from the next point of starting point；Otherwise, to searching point
Previous step E4 of pressing around not judged continues to judge；
(E7) judge whether new point belongs in boundary line L set, the most then enter step
E8；If it is not, new point is stored in boundary line L set, length X of boundary line LN
Add 1, the position relationship recording new point with searching point, repeats step using new point as searching point
Rapid E4, step E5；
(E8) judge that whether new point is the starting point of boundary line L, the most then boundary line L
Search terminates, and obtains a new boundary line；If it is not, now the point set of boundary line L is combined into
{P0,P1..., PM-1,PM,PM+1,PM+2,…,PM+N, new point is PM, then by { PM,PM+1,…,PM+N}
As a new boundary line, simultaneously will a PM,PM+1,…,PM+NCoordinate move from the L of boundary line
Remove, by length X of boundary line LNDeduct the coordinate removed to count, then to a PM-1The most not
Step E4 of pressing judged continues to judge；
(E9) often obtain a new boundary line, will be located in depositing a little within this boundary line
Store up to point of rejection set；This new boundary line length X is detected decision content X with constant simultaneouslyL
Compare, if X is ＜ XL, new boundary line is given up, new boundary line stores a little to
In point of rejection set, if X >=XL, new boundary line is preserved；
(E10) comparing the length of all boundary lines of storage, in output longest edge boundary line, each point is sat
Mark.
2. contact-free level as claimed in claim 1 measures system, it is characterised in that: institute
In step A stated, at original tristimulus value R, G, the B of any one pixel and gray processing
Gray value f after reason meets following relational expression, gray value f=0.299R+0.587G+
0.114B。
3. contact-free level as claimed in claim 2 measures system, it is characterised in that: institute
In step B stated, by following transformation relation, the gray value f of pixel each in image is carried out
Conversion obtains new gray value g: if 0≤f is ＜ a, then g=α f；If a≤f ＜ b, then g=
β (f-a)+ga；If b≤f≤255, then g=γ (f-b)+gb；A in formula, b, α,
β、γ、ga、gbIt is constant.
4. contact-free level as claimed in claim 3 measures system, it is characterised in that: institute
In step C stated, by 0≤g≤gxPixel be filled to black and be labeled as 1, gx＜ g≤
The pixel of 255 is filled to white and is labeled as 0, described gxThreshold value for binary conversion treatment.
5. contact-free level as claimed in claim 4 measures system, it is characterised in that: institute
The probe (10) stated is positioned at the oblique top of fluid reservoir and arranges, in described step F, including as follows
Step:
(F1) image is divided into four regions by two diagonal of image；
(F2) each point coordinates in longest edge boundary line in the region that probe is farthest is taken, and according to this
A little coordinates are found out closest to the parabolic equation in longest edge boundary line in this region.
6. contact-free level as claimed in claim 5 measures system, it is characterised in that: institute
The parabolical general equation stated is:
((x-h)sinθ+(y-k)cosθ)2=2p ((x-h) cos θ+(y-k) sin θ),
Wherein, θ is the parabola angle by rotation counterclockwise, and (h k) is parabolical summit
Coordinate, p is parabolical focal length；In described step G the parameter of parabolic equation i.e. (h, k, p,
θ)。
7. the contact-free level as described in any one of claim 1-6 measures system, its feature
It is: between described probe (10) and image pick-up card (21), be provided with optical transmitter and receiver (30),
Optical transmitter and receiver (30) includes optical sender (31), photoreceiver (32), optical sender (31)
Input with probe (10) outfan be connected, the outfan of photoreceiver (32) and figure
As the input of capture card (21) is connected, between optical sender (31) and photoreceiver (32)
Carried out data transmission by optical fiber (33).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310751029.9A CN103743452B (en) | 2013-12-30 | 2013-12-30 | Contact-free level measures system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310751029.9A CN103743452B (en) | 2013-12-30 | 2013-12-30 | Contact-free level measures system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN103743452A CN103743452A (en) | 2014-04-23 |
| CN103743452B true CN103743452B (en) | 2016-08-17 |
Family
ID=50500492
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201310751029.9A Active CN103743452B (en) | 2013-12-30 | 2013-12-30 | Contact-free level measures system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN103743452B (en) |
Families Citing this family (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105222850A (en) * | 2015-10-18 | 2016-01-06 | 内蒙古科技大学 | Based on the liquid level non-contact measurement system of LabVIEW |
| CN105350071B (en) * | 2015-10-23 | 2017-09-22 | 西安理工大学 | A kind of straight pulling silicon single crystal furnace liquid-level detecting method for suppressing fluctuation |
| CN105526993B (en) * | 2016-01-29 | 2019-01-04 | 上海云鱼智能科技有限公司 | Machine vision level-sensing device and its method for measuring material position |
| TWI590190B (en) * | 2016-05-26 | 2017-07-01 | 財團法人成大水利海洋研究發展文教基金會 | Method for image recognition of liquid |
| CN106525194B (en) * | 2016-11-21 | 2019-03-22 | 北京殷图网联科技股份有限公司 | A kind of main transformer oil level method for real-time monitoring equivalent based on limit oil temperature |
| CN106969808B (en) * | 2017-04-11 | 2021-11-19 | 浙江农林大学暨阳学院 | Reservoir water level data acquisition system based on vision |
| CN107450428A (en) * | 2017-08-08 | 2017-12-08 | 国网重庆市电力公司江津供电分公司 | A kind of main transformer oil level method for real-time monitoring equivalent based on translation |
| DE102017123529A1 (en) * | 2017-10-10 | 2019-04-11 | Endress+Hauser SE+Co. KG | Method for determining the filling level of a filling material located in a container |
| CN108252740B (en) * | 2018-03-15 | 2023-04-18 | 中国矿业大学(北京) | Image-based mine water burst and water sump water storage capacity monitoring system |
| CN108457700B (en) * | 2018-03-15 | 2023-04-18 | 中国矿业大学(北京) | Mine sump monitoring alarm system based on infrared image |
| CN112819749A (en) * | 2020-12-30 | 2021-05-18 | 中冶赛迪重庆信息技术有限公司 | Method, system, medium and terminal for identifying liquid level of tapping ladle of converter |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6098029A (en) * | 1994-06-14 | 2000-08-01 | Hitachi, Ltd. | Liquid-level position measuring method and system |
| CN1804559A (en) * | 2006-01-19 | 2006-07-19 | 昆明利普机器视觉工程有限公司 | Water level meter with digital video frequency |
| CN202101731U (en) * | 2011-02-25 | 2012-01-04 | 秦皇岛玻璃工业研究设计院 | Glass liquid level pickup measuring device |
| CN102494733A (en) * | 2011-12-12 | 2012-06-13 | 西安电子科技大学 | Water level monitoring system based on image processing and method |
| CN203964982U (en) * | 2013-12-30 | 2014-11-26 | 合肥金星机电科技发展有限公司 | Contactless liquid level measuring system |
-
2013
- 2013-12-30 CN CN201310751029.9A patent/CN103743452B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6098029A (en) * | 1994-06-14 | 2000-08-01 | Hitachi, Ltd. | Liquid-level position measuring method and system |
| CN1804559A (en) * | 2006-01-19 | 2006-07-19 | 昆明利普机器视觉工程有限公司 | Water level meter with digital video frequency |
| CN202101731U (en) * | 2011-02-25 | 2012-01-04 | 秦皇岛玻璃工业研究设计院 | Glass liquid level pickup measuring device |
| CN102494733A (en) * | 2011-12-12 | 2012-06-13 | 西安电子科技大学 | Water level monitoring system based on image processing and method |
| CN203964982U (en) * | 2013-12-30 | 2014-11-26 | 合肥金星机电科技发展有限公司 | Contactless liquid level measuring system |
Also Published As
| Publication number | Publication date |
|---|---|
| CN103743452A (en) | 2014-04-23 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103743452B (en) | Contact-free level measures system | |
| CN109977780A (en) | A kind of detection and recognition methods of the diatom based on deep learning algorithm | |
| CN112699876B (en) | Automatic reading method for various meters of gas collecting station | |
| CN111950330B (en) | Pointer instrument indication detection method based on target detection | |
| CN105260709B (en) | Water meter calibration method, apparatus based on image procossing and system | |
| CN111476159B (en) | Method and device for training and detecting detection model based on double-angle regression | |
| CN105260710B (en) | Water meter calibration method, apparatus based on image procossing and system | |
| CN108154508A (en) | Method, apparatus, storage medium and the terminal device of product defects detection positioning | |
| CN105300482B (en) | Water meter calibration method, apparatus based on image procossing and system | |
| CN102975826A (en) | Portable ship water gauge automatic detection and identification method based on machine vision | |
| CN105389814A (en) | Air bubble detection method for air tightness test | |
| Sivkov et al. | The algorithm development for operation of a computer vision system via the OpenCV library | |
| CN107944357A (en) | Multi-source Remote Sensing Images cloud detection method of optic based on evidence fusion adaptive threshold | |
| CN101709951A (en) | Method for measuring and recording phenotypic characters of scallop by computer | |
| CN111598098A (en) | Water gauge water line detection and effectiveness identification method based on full convolution neural network | |
| CN102324032A (en) | Texture feature extraction method for gray level co-occurrence matrix in polar coordinate system | |
| CN106023153B (en) | A kind of method of bubble in measurement water body | |
| CN112906455A (en) | Coastal zone ecological system remote sensing identification method | |
| CN109508709A (en) | A kind of simple pointer meter reading method based on machine vision | |
| CN112200050A (en) | Lake water volume space-time change analysis method and device based on multi-source satellite data | |
| Robb et al. | Semi-automated field plot segmentation from UAS imagery for experimental agriculture | |
| CN116415843A (en) | Multi-mode remote sensing auxiliary mine ecological environment evaluation method for weak network environment | |
| CN114066887B (en) | Rice chalkiness area detection method, device, equipment and storage medium | |
| Dou et al. | Research on water-level recognition method based on image processing and convolutional neural networks | |
| CN203964982U (en) | Contactless liquid level measuring system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CP03 | Change of name, title or address | ||
| CP03 | Change of name, title or address |
Address after: 230000 No. 228, Wanshui Road, high tech Zone, Hefei, Anhui Patentee after: Hefei Jinxing Intelligent Control Technology Co.,Ltd. Address before: High tech Zone Hefei city Anhui province 230088 Tianzhi Road No. 23 Patentee before: HEFEI GOLD STAR MECHATRONICS TECHNICAL DEVELOPMENT Co.,Ltd. |