CN109242908A - Scaling method for underwater two CCD camera measure system - Google Patents
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Abstract
The invention belongs to undersea detections and field of measuring technique, it is intended to the problem of solving existing underwater two CCD camera measure system and do not have generality, can not being applied to the higher occasion of precision, thus not be able to satisfy all undersea detections and measurement demand.For this purpose, demarcating in air to binocular camera the present invention provides a kind of scaling method for underwater two CCD camera measure system, Intrinsic Matrix and distortion parameter are obtained；It shoots the line distortion of going forward side by side of tessellated image using binocular camera under water to correct, detection obtains X-comers, measures corner location coordinate by reflecting relationship under water；According to relative positional relationship design optimization target between X-comers, the calibration of underwater two CCD camera measure system is completed with multiple-objection optimization.The measurement accuracy of underwater two CCD camera measure system can be improved in the present invention, can meet the needs of precision high field conjunction, improve the generality of underwater two CCD camera measure system, be able to satisfy all undersea detections and measurement demand.
Description
Technical field
The invention belongs to undersea detections and field of measuring technique, specifically provide a kind of for underwater two CCD camera measure system
Scaling method.
Background technique
As an important branch of marine survey technology, the undersea detection based on underwater robot is made extensively
With.In the undersea detection and measurement using robot vision technology, since vision system is mostly protected by anti-sump, lead to light
Occur to reflect twice when entering camera, aerial camera calibration technology not can be used directly the calibration in underwater camera.
It, in the prior art can be big about the solution of this problem for refraction to the influence during camera imaging
Cause is divided into five classes, and the first kind is physical method, offsets refraction effect by designing special optical component, the method is to optical section
The technique requirement of part is very high, is not easy to manufacture；Second class is the method using auxiliary plane, that is, passes through an auxiliary calibration
Plate determines direction vector when light incidence, but the operation of the method is more complicated, is not suitable for promoting and applying；Third class side
Refraction is treated as focal length variations by method, but when angle of incidence of light is big, error also can be very big using the method, to cause to survey
It is larger to measure deviation；4th class is that the error reflected under water is regarded as lens distortion, is corrected processing to image, this method is
Linear national forest park in Xiaokeng is continued to use, error is still very big；5th class is to establish the refraction model of underwater camera, is carried out
The accuracy of the calibration of underwater camera, this mode is higher.
At home, underwater camera refraction model has been carried out there are many researcher of company and university and has widely ground
Study carefully, and proposes the underwater camera scaling method based on multilayer planar refraction geometry and the underwater measurement system mark based on population
It is the methods of fixed, such as in the patent that number of patent application is CN201511019268.0, propose a kind of underwater camera calibration side
Method, the patent is although it is contemplated that the influence of underwater refraction, but its method assumes that camera imaging plane normal vector and refraction
Plane normal vector is parallel, and has ignored the wall thickness of anti-sump, therefore does not have generality, i.e., in the higher application of precision
It can not apply, not be able to satisfy the demand of all undersea detections and measurement.
Therefore, this field needs the scaling method for underwater two CCD camera measure system of one kind newly to solve above-mentioned ask
Topic.
Summary of the invention
In order to solve the above problem in the prior art, do not have in order to solve existing underwater two CCD camera measure system
Generality can not be applied to the higher occasion of precision, thus the problem of be not able to satisfy all undersea detections and measurement demand.This
Invention provides a kind of scaling method for underwater two CCD camera measure system, which includes position
First camera in left side and the second camera positioned at right side, the scaling method include:
First camera and second camera are demarcated in air, obtain the intrinsic parameter square of first camera and second camera
Module and carriage transformation matrix between battle array, distortion factor and first camera and second camera；
Tessellated image is shot by first camera and second camera under water；
Distortion school is carried out to the image of first camera by the distortion factor of the Intrinsic Matrix of first camera, first camera
Just, distortion correction is carried out to the image of second camera by the distortion factor of the Intrinsic Matrix of second camera, second camera；
Using the method for Corner Detection, coordinate and gridiron pattern angle of the X-comers on the image of first camera are obtained
Coordinate of the point on the image of second camera；
Obtain the measured value of corner location coordinate；
It is excellent by multiple target using the optimization aim of the relative positional relationship design calibration process of scaling board X-comers
The underwater two CCD camera measure system is demarcated in change.
In the optimal technical scheme of above-mentioned scaling method, " first camera and second camera are being marked in air
It is fixed, obtain the position between the Intrinsic Matrix, distortion factor and first camera and second camera of first camera and second camera
Before the step of appearance transformation matrix ", the scaling method further include:
Set first camera and the underwater precompensation parameter value of second camera.
In the optimal technical scheme of above-mentioned scaling method, the step of measured value of corner location coordinate " obtain ", is specifically wrapped
It includes:
The precompensation parameter value is substituted into following equation, it may be assumed that
P=f (Pl,Pr,R,dl,dr,h,nx,ny,nz),
Obtain the measured value of corner location coordinate, wherein
P indicates the position of submarine target point, PlAnd PrRespectively indicate pixel of the target point in the image of first camera with
And the pixel in the image of second camera, module and carriage transformation matrix of the R between first camera and second camera, dlAnd drRespectively
Indicate that the optical center of first camera is flat to first layer refraction to the vertical range of first layer plane of refraction and the optical center of second camera
The vertical range in face, h are the thickness of the anti-sump of the underwater two CCD camera measure system, nx, nyAnd nzIt is plane of refraction normal direction
Measure the x-axis on the basis of first camera coordinate system, y-axis, the coordinate components of z-axis.
The precompensation parameter value is referred to { dl,dr,h,nx,ny,nzEstimation.
In the optimal technical scheme of above-mentioned scaling method, " set using the relative positional relationship of scaling board X-comers
The optimization aim for counting calibration process, demarcates the underwater two CCD camera measure system by multiple-objection optimization " the step of
It specifically includes:
Set the first optimization aim, it may be assumed that
min∑(|Cm i,j-Cm i+1,j|+|Cm i,j-Cm i,j+1| -2w),
Wherein, the measured value of corner location coordinate is Cm i,j, i is the horizontal direction serial number of X-comers, and j is gridiron pattern
The vertical direction serial number of angle point, w are the side length of the gridiron pattern grid；
Set the second optimization aim, it may be assumed that
Set third optimization aim, it may be assumed that
It is optimized based on the first optimization aim, the second optimization aim and third optimization aim, thus to described underwater
Two CCD camera measure system is demarcated.
In the optimal technical scheme of above-mentioned scaling method, the Intrinsic Matrix of the first camera are as follows:
Wherein, fxlAnd fylFor the focal length of first camera, xolAnd yolFor the principal point coordinate relative to imaging plane.
In the optimal technical scheme of above-mentioned scaling method, the Intrinsic Matrix of the second camera are as follows:
Wherein, fxrAnd fyrFor the focal length of second camera, xorAnd yorFor the principal point coordinate relative to imaging plane.
It will be appreciated to those of skill in the art that in the preferred technical solution of the present invention, it in air can be to
One camera and second camera are demarcated to obtain the Intrinsic Matrix of first camera and second camera and distortion factor, then
Tessellated image is shot by first camera and second camera under water, then by the Intrinsic Matrix of first camera and abnormal
Variable coefficient is corrected the tessellated image that first camera takes, and is by the Intrinsic Matrix and distortion of second camera
The tessellated image that several pairs of second cameras take is corrected, and next obtains gridiron pattern angle using the method for Corner Detection
Point finally combines angle point in the coordinate of coordinate and X-comers on the image of second camera on the image of first camera
The measured value of position coordinates demarcates underwater two CCD camera measure system, in this way, can be improved underwater
The measurement accuracy of two CCD camera measure system can meet the needs of precision high field conjunction, improve underwater binocular vision and survey
The generality of amount system can meet all undersea detections and measurement demand, and then can be widely applied to regard under water
The fields such as feel accurately measures, undersea detection and underwater robot operation.
Further, by the first optimization aim of setting, the second optimization aim and third optimization aim, that is, scaling board is used
The relative positional relationship of X-comers designs the optimization aim of calibration process, in this way can turn problem of calibrating
It is changed to multi-objective optimization question, in optimization process, and underwater camera parameter is constantly updated, finally realizes underwater binocular vision
The calibration of measuring system, to accurately obtain the calibration result of underwater camera parameter.
Detailed description of the invention
Fig. 1 is underwater camera refraction model schematic diagram of the invention；
Fig. 2 is that underweater vision measuring system class trigonometric ratio of the invention determines aiming spot schematic diagram；
Fig. 3 is scaling board X-comers relative positional relationship design optimization object delineation of the invention；
Fig. 4 is that underweater vision measuring system of the invention demarcates measure of merit result schematic diagram.
Specific embodiment
The preferred embodiment of the present invention described with reference to the accompanying drawings.It will be apparent to a skilled person that this
A little embodiments are used only for explaining technical principle of the invention, it is not intended that limit the scope of the invention.
It should be noted that in the description of the present invention, term " first ", " second " are used for description purposes only, and cannot
It is interpreted as indication or suggestion relative importance.
The existing underwater two CCD camera measure system pointed out based on background technique does not have generality, can not be applied to precision
Higher occasion, thus the problem of be not able to satisfy all undersea detections and measurement demand.The present invention provides one kind to be used for water
The scaling method of lower two CCD camera measure system, it is intended to the measurement accuracy for improving underwater two CCD camera measure system, it can
Meet the needs of precision high field conjunction, improves the generality of underwater two CCD camera measure system, all underwater spies can be met
Survey and measurement demand.
In the present invention, due to being protected outside underwater camera by anti-sump, so light, which reaches target point from camera photocentre, to be needed
It by reflecting twice is connected surface (calling first layer plane of refraction in the following text) and anti-sump and water in air and anti-sump respectively
Connect surface (calling second layer plane of refraction in the following text).Therefore, it is necessary to first establish the refraction model of underwater camera, in this, it is assumed that refraction
It is parallel to each other between plane.
As shown in Figure 1, O is the optical center of camera, the bottom surface of triangle is camera imaging plane, and camera coordinates system is original with O
Point is established, and Z axis is camera optical axis direction, and X-direction is vertical with Z-direction as shown in Figure 1；Light reaches target point P from optical center
Optical path by twice refraction be divided into three sections, the direction vector of first segment to third section is respectively by r0, r1And r2It indicates；X0It indicates
The intersection point of optical path and imaging plane, i.e. coordinate of the picture point under camera coordinates system where target point, can be by image pixel coordinates
Point is found out by camera focus relationship；X1And X2The intersecting point coordinate of optical path and first layer plane of refraction where respectively indicating target point
With the intersecting point coordinate of optical path and second layer plane of refraction where target point；nπThe normal vector of plane of refraction is indicated, to keep general
Property, when analysis, are not parallel with optical axis direction；D and h respectively indicates vertical range and anti-sump of the optical center to first layer plane of refraction
Thickness, unit is millimeter；μ0, μ1And μ2Respectively represent the refractive index of air, anti-sump material and water.
With continued reference to Fig. 1, the direction vector of first segment optical path acquires according to the following equation (1), it may be assumed that
The intersecting point coordinate of optical path and first layer plane of refraction where target point is indicated by following formula (2), it may be assumed that
According to the law of refraction it is found that r0, r1And nπBetween meet following relationship, i.e. formula (3):
r1=α0r0+β0nπ
Wherein, α0=μ0/μ1,Similarly, X2And r2It can be acquired.Extremely
This, starting point and the direction vector of third section optical path where target point are it is found that the linear equation of target point third section optical path can be in the hope of
It takes.
By a camera, the linear equation of the third section of optical path, is but unable to get target where available target point
The position of point.As shown in Fig. 2, for the same target point, two optical paths will be obtained in two cameras in left and right, two articles of optical paths the
Three sections of linear equation can be acquired by the method for above-mentioned formula (1) (2) (3).Theoretically, two straight lines pass through left and right phase seat in the plane
After appearance transformation matrix R is transformed into the same coordinate system, the intersecting point coordinate of the two is the position of target point.But since processing misses
The presence of difference, two straight lines possibly can not intersect, then take the midpoint of two straight line common vertical lines as aiming spot, seek target
The method of point position is class Triangulation Algorithm.
So far, by establishing the refraction model of underwater camera, it can learn that target point position meets as follows in water
Non-linear relation, i.e., following formula (4):
P=f (Pl,Pr,R,dl,dr,h,nx,ny,nz)
In above-mentioned non-linear relation, P indicates the position of submarine target point, PlAnd PrTarget point is respectively indicated in left and right
Pixel in image, module and carriage transformation matrix of the R between the camera of left and right, dlAnd drLeft and right camera photocentre is respectively indicated to first
The vertical range of layer plane of refraction, h is the wall thickness of anti-sump, nx, nyAnd nzIt is plane of refraction normal vector with left camera coordinate system
On the basis of x, y, the coordinate components of z-axis.
For be elaborated formula (4) mathematical relationship calculation method, referring to Fig. 2, specific explanations are as follows:
The optical path of left and right camera where target point P and the intersection point of second layer plane of refraction are respectively PWG, lAnd PWG, r, target point
The direction vector of the third section optical path of the optical path of left and right camera is respectively r where PlWith rr；In PlAnd PrUnder the premise of known, root
It is easy to acquire intersection point P according to above-mentioned formula (1) (2) (3)WG, lAnd PWG, rAnd direction vector rlAnd rr；This sentences left camera optical path
For, derivation process is as follows:,
By camera focus relationship, by left image pixel coordinate PlIt is converted into coordinate under left camera coordinate system:
Plc=focal (Pl)
Wherein focal () indicates the function of zooming transform, and specific method is the very conventional prior art, is not explained in detail herein
It states；Next, left camera optical path and first layer plane of refraction intersection point P where target point PAG, lIt can be according to above-mentioned formula (1) (2) following formula
It acquires, it may be assumed that
Wherein
According to formula (3), the direction vector r of second segment optical path1,lIt can be obtained by following formula, it may be assumed that
r1,l=α0,lr0,l+β0,lnπ
Wherein α0,l=μ0/μ1,
Similar to formula (1) (2), left camera optical path and second layer plane of refraction intersection point P where target point PWG,lIt can lead to
It crosses and is acquired by following formula, it may be assumed that
Wherein nπ=(nx,ny,nz)
According to formula (3), the direction vector r of third section optical pathlIt can be obtained by following formula, it may be assumed that
rl=α1,lr1,l+β1,lnπ
Wherein α0,l=μ1/μ2,
It similarly, can be in the hope of the intersection point and third Duan Guang of camera optical path and second layer plane of refraction right where target point P
The direction vector on road；
At this point, obtained intersection point PWG, lAnd PWG, rAnd direction vector rlAnd rrIt is in respective camera coordinates system
In, it should mark transformation matrix by the seat of following formula and transform in left camera coordinates system, it may be assumed that
So far, it is known that in space straight line a little and its direction vector, then the left and right camera optical path where target point P
The linear equation of third section can acquire, so that the midpoint of the perpendicular bisector of two straight lines can also be acquired, the coordinate of target point P is
It can determine；The calculation method of linear equation and perpendicular bisector is the very conventional prior art, is not elaborated herein.
So needing to obtain accurate parameters described below set to obtain the exact position of target point, it may be assumed that
{R,dl,dr,h,nx,ny,nz}
Specifically, underwater two CCD camera measure system of the invention include anti-sump and be arranged in anti-sump first
Camera and second camera, wherein first camera is located at left side (left camera i.e. above-mentioned), and it is (i.e. above-mentioned that second camera is located at right side
Right camera), scaling method of the invention includes:
Step 1: in air demarcating first camera and second camera, obtains first camera and second camera
Module and carriage transformation matrix between Intrinsic Matrix, distortion factor and first camera and second camera；
The Intrinsic Matrix of first camera are as follows:
Wherein, fxlAnd fylFor the focal length of first camera, xolAnd yolFor the principal point coordinate relative to imaging plane.
The Intrinsic Matrix of second camera are as follows:
Wherein, fxrAnd fyrFor the focal length of second camera, xorAnd yorFor the principal point coordinate relative to imaging plane.
Step 2: tessellated image is shot by first camera and second camera under water；
Step 3: by the Intrinsic Matrix of first camera, first camera distortion factor to the image of first camera into
Line distortion correction carries out the image of second camera by the distortion factor of the Intrinsic Matrix of second camera, second camera abnormal
Become correction；
Step 4: using the method for Corner Detection, obtain coordinate of the X-comers on the image of first camera and
Coordinate of the X-comers on the image of second camera；
Step 5: the measured value of corner location coordinate is obtained；
Step 6: it is determined according to the relativeness of X-comers, devises three optimization aims, calibration process is converted
For multi-objective optimization question, to be demarcated to the underwater binocular measuring system.
In the present invention, before above-mentioned step one, underwater camera can be demarcated and joined rule of thumb with actual conditions
{ d in numberl,dr,h,nx,ny,nzValue range primarily determined, and assign reasonable initialization estimated value, that is, set
First camera and the underwater precompensation parameter value of second camera.During estimating, two cameras can be measured by ruler
The deflection of the anti-sump thickness of vertical range, camera and plane of refraction normal vector apart from first layer plane of refraction, so it is right
The value range of underwater camera calibrating parameters is primarily determined.It should be noted that precompensation parameter value can be with art technology
Personnel can actually answer by many experiments or the initialization estimated value obtained according to previous experiences, those skilled in the art
The selected mode of above-mentioned precompensation parameter value is flexibly set in.
In above-mentioned steps five, the camera parameter demarcated in above-mentioned underwater camera parameter prediction value and air is substituted into
In above-mentioned formula (4), to obtain the measured value C of corner location coordinatem i,j, to demarcate underwater camera parameter, the present invention is used
The relative positional relationship design optimization target of X-comers.As shown in figure 3, the opposite position between the tessellated angle point of scaling board
It sets known to relationship.Adjacent distance between two points are it is known that be the side length of gridiron pattern grid；Positioned at same horizontal line or same vertical
Angle point on line, combination of two at vector be parallel to each other；The vector that any two angle point in same horizontal line is combined into
It is parallel to each other with the vector for any two angle point composition being located on same vertical line.The measured value C of angle pointm i,j(i is gridiron pattern
The horizontal direction serial number of angle point, such as X-direction in Fig. 3, j is the vertical direction serial number of X-comers, such as Y-direction in Fig. 3), it answers
When meeting three of the above relative positional relationship, it is correspondingly made available following three optimization aim:
First optimization aim:
min∑(|Cm i,j-Cm i+1,j|+|Cm i,j-Cm i,j+1|-2w)
Wherein w is the side length of gridiron pattern grid；
Second optimization aim:
Third optimization aim:
Technical solution of the present invention is further illustrated below with reference to a specific embodiment, uses one piece 6 × 9
Gridiron pattern is 30 millimeters as scaling board, the side length of grid, carries out calibration experiment in accordance with the following steps.
Step 1: rule of thumb being primarily determined with actual conditions to the value range of underwater camera parameter, and assign
Give reasonable initialization estimated value.
Step 2: in air, being demarcated with gridiron pattern to binocular camera, obtaining the Intrinsic Matrix of left and right camera
IleftAnd Iright, distortion factor vector kleftAnd krightAnd the module and carriage transformation matrix R between the camera of left and right, data are as follows:
kleft=[- 0.1504-0.0114], kright=[- 0.1573 0.0096]；
Wherein, in the first three rows of matrix R, first three is classified as the rotationally-varying relationship between first camera and second camera, most
Latter column represent the change in displacement relationship between first camera and second camera.
Step 3: under water, binocular camera shoots tessellated image, line distortion of going forward side by side correction.
Step 4: obtain the coordinate of X-comers in the picture with angular-point detection method, the wherein seat of left image angle point
It is designated as Pl i, right image angular coordinate is Pr i,j(i is the horizontal direction serial number of X-comers, and j is the vertical side of X-comers
To serial number), left images correspond to each other.
Step 5: the estimated value of underwater camera parameter is substituted into above-mentioned formula (4), the measured value of corner location coordinate is obtained
Cm i,j, i is the horizontal direction serial number of X-comers, and j is the vertical direction serial number of X-comers.
Step 6: the optimization aim of the relative positional relationship design calibration process using scaling board X-comers.Under water
The calibration process conversion of camera parameter constantly updates underwater camera by multi-objective optimization algorithm for multi-objective optimization question
Parameter finally realizes the calibration of underwater binocular measuring system, obtains the calibration result of underwater camera parameter:
dl=14.98, dr=14.56, h=6.53, nx=0.0011, ny=0.0998, nz=0.9950.
It needs to illustrate, multiple-objection optimization is a mature mathematical calculation process, in optimization aim and to be optimized
Under the premise of parameter is known, this process is easily achieved.Different optimization algorithms can be selected herein to demarcate underwater camera ginseng
Number.For the relationship between clear underwater camera parameter calibration and multiple-objection optimization, the following formula of calibration process, it may be assumed that
Wherein, F1, F2And F3Respectively represent first optimization aim, the second optimization aim, third optimization aim.Upper
During stating multiple-objection optimization, underwater camera parameter will be continuously available optimization, substitute into formula (4) obtained X-comers
Relative position between measured value coordinate will move closer to the relative positional relationship between the true value coordinate of X-comers,
So as to realize effective underwater camera calibration.
In addition, the present invention has also carried out gridiron pattern location point experiment with computing to calibrated underweater vision measuring system, with
Verifying scaling method has good measurement performance.For selected test gridiron pattern having a size of 8 × 11, the side length of grid is 25 millimeters.
As shown in figure 4, the dot matrix A of the rightmost side is the true value of gridiron pattern position, dot matrix B is underwater measurement system this method in diagram
Calibrated measured value, dot matrix C is the measured value of the calibrated underwater measurement system of traditional scaling method one in diagram, in diagram
Dot matrix D is the calibrated measured value of traditional scaling method two, wherein conventional method one is that the error reflected under water is regarded as camera lens
Distortion carries out correction process to image；Conventional method two is not consider to reflect directly with the binocular vision method in air.It can be with
See, method of the invention is more nearly with true value, and the average position error of corresponding points only has 17.89 millimeters, and accuracy is more
It is high.
So far, it has been combined preferred embodiment shown in the drawings and describes technical solution of the present invention, still, this field
Technical staff is it is easily understood that protection scope of the present invention is expressly not limited to these specific embodiments.Without departing from this
Under the premise of the principle of invention, those skilled in the art can make equivalent change or replacement to the relevant technologies feature, these
Technical solution after change or replacement will fall within the scope of protection of the present invention.
Claims (6)
1. a kind of scaling method for underwater two CCD camera measure system, which is characterized in that the underwater Binocular vision photogrammetry
System includes the second camera positioned at the first camera in left side and positioned at right side, and the scaling method includes:
First camera and second camera are demarcated in air, obtain first camera and second camera Intrinsic Matrix,
Module and carriage transformation matrix between distortion factor and first camera and second camera；
Tessellated image is shot by first camera and second camera under water；
Distortion correction is carried out to the image of first camera by the distortion factor of the Intrinsic Matrix of first camera, first camera,
Distortion correction is carried out to the image of second camera by the distortion factor of the Intrinsic Matrix of second camera, second camera；
Using the method for Corner Detection, obtains coordinate and X-comers of the X-comers on the image of first camera and exist
Coordinate on the image of second camera；
Obtain the measured value of corner location coordinate；
Using the optimization aim of the relative positional relationship design calibration process of scaling board X-comers, pass through multiple-objection optimization pair
The underwater two CCD camera measure system is demarcated.
2. scaling method according to claim 1, which is characterized in that " in air to first camera and second camera
Demarcated, obtain first camera and second camera Intrinsic Matrix, distortion factor and first camera and second camera it
Between module and carriage transformation matrix " the step of before, the scaling method further include:
Set first camera and the underwater precompensation parameter value of second camera.
3. scaling method according to claim 2, which is characterized in that the step of the measured value of corner location coordinate " obtain "
It specifically includes:
The precompensation parameter value is substituted into formula (1), it may be assumed that
P=f (Pl,Pr,R,dl,dr,h,nx,ny,nz) (1)
Obtain the measured value of corner location coordinate, wherein
P indicates the position of submarine target point, PlAnd PrRespectively indicate pixel and of the target point in the image of first camera
Pixel in the image of two cameras, module and carriage transformation matrix of the R between first camera and second camera, dlAnd drIt respectively indicates
The optical center of first camera is to the vertical range of first layer plane of refraction and the optical center of second camera to first layer plane of refraction
Vertical range, h are the thickness of the anti-sump of the underwater two CCD camera measure system, nx, nyAnd nzPlane of refraction normal vector with
X-axis on the basis of first camera coordinate system, y-axis, the coordinate components of z-axis.
4. scaling method according to claim 1, which is characterized in that " use the relative position of scaling board X-comers
The optimization aim of relational design calibration process demarcates the underwater two CCD camera measure system by multiple-objection optimization "
The step of specifically include:
Set the first optimization aim, it may be assumed that
min∑(|Cm i,j-Cm i+1,j|+|Cm i,j-Cm i,j+1| -2w),
Wherein, the measured value of corner location coordinate is Cm i,j, i is the horizontal direction serial number of X-comers, and j is X-comers
Vertical direction serial number, w be the gridiron pattern grid side length；
Set the second optimization aim, it may be assumed that
Set third optimization aim, it may be assumed that
It is optimized based on the first optimization aim, the second optimization aim and third optimization aim, thus to the underwater binocular
Vision measurement system is demarcated.
5. scaling method according to claim 1, which is characterized in that the Intrinsic Matrix of the first camera are as follows:
Wherein, fxlAnd fylFor the focal length of first camera, xolAnd yolFor the principal point coordinate relative to imaging plane.
6. scaling method according to claim 1, which is characterized in that the Intrinsic Matrix of the second camera are as follows:
Wherein, fxrAnd fyrFor the focal length of second camera, xorAnd yorFor the principal point coordinate relative to imaging plane.
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