CN105469112B - Image Feature Matching method and system based on local linear migration and rigid model - Google Patents
Image Feature Matching method and system based on local linear migration and rigid model Download PDFInfo
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Abstract
The invention proposes a kind of Image Feature Matching method and system based on local linear migration and rigid transformation, correct matching is established for the matching of the mistake by removal initial matching point centering, the corresponding model of geometric transformation between image to be matched is established in rigid geometric transformation including being directed between image to be matched, and establishing matching double points is the correct matched corresponding model of posterior probability, is based on nearest-neighbors match point, least square method, optimal method solving model parameter;Initial matching point is calculated to for correctly matched posterior probability, and according to threshold decision initial matching point to correcting errors.This method to be modeled for there are the case where rigid transformation between image to be matched, matched error rate is significantly reduced, even if still keeping good robustness there are in the case where a large amount of erroneous matchings in preliminary matches.
Description
Technical field
The present invention relates to Image Feature Matching technical fields, specifically, the present invention relates to based on local linear migration and
The Image Feature Matching technical solution of rigid model.
Background technique
The elementary object of images match be will use different sensors in different times with obtained under visual angle it is same
The same area of the two images of scene is corresponded to.
In in the past few decades, scholars have studied many methods to solve remote sensing images matching problem.These methods
It can be roughly divided into two types: matching process and feature-based matching method based on region.The former passes through search two images
The similarity degree of original gray value finds match information in middle certain area;The latter then utilizes description of local feature similar
Property or space geometry constraint to find matching double points.In the case where there is a small amount of significant details, the information ratio of gray value offer
Local shape and structure are more, so that the matching effect of the method based on region is more preferable.But the method calculation amount based on region
Greatly, it and in the case where image fault and luminosity change and is not suitable for.On the contrary, characterization method has better robustness, it can be with
The image for handling babble, is widely used.
How to find corresponding match point in two images, form matching double points, and ensures that the correctness of matching double points is
The key of image matching method.
Matching process based on region mainly has correlation method, Fourier methods and three kinds of mutual information method.Correlation method it is main
Thought is to calculate the similitude that window is corresponded in two images, then will have a pair of maximum similarity degree as matching double points.
But correlation method can not be applicable in the inapparent texture-free region of similitude, and be calculated complicated.Fourier methods are utilized image and exist
The Fourier Representations of frequency domain.Compared with traditional correlation technique, this method is higher in computational efficiency and makes an uproar to frequency class
Sound has good robustness.However, this method has certain restrictions with the image of different spectrum structures in processing.Mutual trust
For breath method although its matching effect is good, it is unable to get the global maximum in entire search space, therefore inevitable
Meeting lower its robustness.
In feature-based matching method, a kind of strategy for being divided into two steps is generallyd use.The first step is retouched by feature
The similarity degree for stating son determines one group of initial matching double points, and wherein the overwhelming majority is correctly to match, but inevitably contain
A large amount of erroneous matching.Second step finally can be matched correctly by removing the matching of mistake by geometrical constraint
Point is to the geometric parameter converted between two images.The typical example of this strategy includes RANSAC method
(M.A.Fischler and R.C.Bolles,“Random sample consensus:A paradigm for model
fitting with application to image analysis and automated cartog-raphy,”
Commun.ACM, vol.24, no.6, pp.381-395, Jun.1981), ARHV method (P.H.S.Torr and
A.Zisserman,“MLESAC:A new robust estimator with application to estimating
image geometry,”Comput.Vis.Image Under-stand.,vol.78,no.1,pp.138–156,
) etc. Apr.2000 the method and VFC method (J.Ma, J.Zhao, J.Tian, A.L.Yuille, and of parameter model are depended on
Z.Tu,“Robust point matching via vector field consensus,”IEEE Trans.Image
Process., vol.23, no.4, pp.1706-1721, Apr.2014.), GS method (H.Liu and S.Yan, " Common
visual pattern discovery via spatially coher-ent correspondence,”in Proc.IEEE
Conf.Comput.Vis.Pattern Recog., Jun.2010, pp.1609-1616.) and ICF method (X.Li and
Z.Hu,“Rejecting misma tches by correspondence function,”Int.J.Comput.Vis.,
Vol.89, no.1, pp.1-17, Aug.2010) method based on nonparametric model such as.
Although these methods obtain success in many fields, in the picture containing largely because of visual angle change caused by
The initial matching point pair that many mistakes can be obtained when localized distortion and more complex picture material, after preliminary matches, works as error rate
When more than certain proportion, these methods cannot effectively remove mistake.Therefore needing a kind of pair of initial matching error rate has
The matching process of higher robustness.
Summary of the invention
For prior art defect, the invention proposes a kind of characteristics of image based on local linear migration and rigid model
Matching technique scheme.
In order to achieve the above objectives, the technical solution adopted by the present invention provides a kind of based on local linear migration and rigid model
Image Feature Matching method, include the following steps,
Step 1, establishing the corresponding model of geometric transformation and matching double points between image to be matched is that correct matched posteriority is general
The corresponding model of rate, realization is as follows,
For the rigid geometric transformation between image to be matched, foundation transformation mathematical model is as follows,
Y=t (x)=sRx+o
Wherein, if two width image to be matched are image a and image b, x and y are the seat of pixel on image a and image b respectively
Vector is marked, t (x) indicates that rigid geometric transform relation, s indicate the dimension scale between image to be matched, and R is one 2 × 2 square
Battle array indicates the rotation between image to be matched, and o is one 2 × 1 matrix, indicates the translation between image to be matched;
If known one group of initial matching point centering, point set is X={ x on image a1,…,xN}T, corresponding point set on image b
For Y={ y1,…,yN}T, calculating wherein n-th pair of match point is correct matched posterior probability pnThere is following posterior probability mathematical modulo
Type,
Wherein, γ and σ is model parameter, and e is mathematics constant, and b is preset coefficient;
Step 2, according to point set X={ x1,…,xN}TWith Y={ y1,…,yN}TSolving model parameter, including following sub-step
Suddenly,
It step 2.1, is each match point xn, n=1 ..., N search for K nearest neighbours' match point respectively, and K takes pre-
If value;
Step 2.2, according to the search result of step 2.1, least square method is used to solve dimension as the weight matrix of N × N
W;
Step 2.3, by optimal method solving model parameter s, R, o, γ, σ, including following sub-step,
Step 2.3.1, initialization, including enable γ=γ0, R=I2×2, o=0, P=IN×N, γ0For the default initial of γ
Value, enables current iteration number k=1, calculates σ using following model parameter formula,
Wherein, matrix T=(t (x1),…,t(xN))T, tr () indicates to seek the mark of matrix;
Step 2.3.2, updates matrix P, including using gained posterior probability mathematical model in step 1, be calculated N to
With point to respectively correct matched posterior probability p1,…,pN, enable P=diag (p1,…,pN), diag indicates diagonal matrix;
Step 2.3.3, calculating parameter s, R, o are as follows,
Using following formula calculating parameter s,
Wherein, matrix
By IN×NOmission is denoted as I, matrix Q=(I-W)TP (I-W), λ are preset parameter;
Using following formula calculating parameter R,
R=UDVT
Wherein, D=diag (1, det (UVT)), the determinant of det () representing matrix, matrix U and V pass through singular value decomposition
It obtains;Using following formula calculating parameter o,
O=μy-sRμx
Step 2.3.4, parameter s, R, the o being calculated according to step 2.3.3, it is as follows to recalculate parameter γ, σ,
Using following formula calculating parameter γ,
σ is calculated using model parameter formula in step 2.3.1;
Step 2.3.5 differentiates the condition of convergence, including calculating current parameter L, when meeting k=kmaxOr (L-Lold)/
Lold≤ ε terminates iteration, kmaxFor maximum number of iterations, ε is convergence threshold;Otherwise, k=k+1, return step 2.3.2;It is described
The calculation formula of parameter L is as follows,
Wherein, LoldIndicate the last L being calculated;
Step 3, initial matching point is calculated to for correctly matched posterior probability, and according to threshold decision initial matching point pair
Correct errors, realize it is as follows,
The model parameter solved in the step 2.3 is substituted into posterior probability mathematical model described in step 1, is calculated
N-th pair of matching double points is correct matched posterior probability;Work as pnWhen >=threshold, then it is assumed that n-th pair of match point is correct
Match;Work as pnWhen < threshold, then it is assumed that n-th pair of match point is the matching of mistake, and wherein threshold is preset judgement threshold
Value.
Moreover, step 2.2 includes following sub-step,
Step 2.2.1, as match point xjIt is not the match point x searched in the step 2.1iK neighbours' match point it
For the moment, then by WijIt is set as 0, wherein match point xjWith match point xiFor the match point in point set X, and i, j=1 ..., N, WijTable
Show the element of weight matrix W the i-th row jth column;
Step 2.2.2,Constraint condition under, solve to obtain using least square method so that following generations
Valence function E (W) gets the weight matrix W of minimum value, and cost function E (W) is as follows,
The present invention correspondingly provides a kind of Image Feature Matching system based on local linear migration and rigid model, including
With lower module,
Model construction module is correct for establishing the corresponding model of geometric transformation and matching double points between image to be matched
The corresponding model of the posterior probability matched, realization is as follows,
For the rigid geometric transformation between image to be matched, foundation transformation mathematical model is as follows,
Y=t (x)=sRx+o
Wherein, if two width image to be matched are image a and image b, x and y are the seat of pixel on image a and image b respectively
Vector is marked, t (x) indicates that rigid geometric transform relation, s indicate the dimension scale between image to be matched, and R is one 2 × 2 square
Battle array indicates the rotation between image to be matched, and o is one 2 × 1 matrix, indicates the translation between image to be matched;
If known one group of initial matching point centering, point set is X={ x on image a1,…,xN}T, corresponding point set on image b
For Y={ y1,…,yN}T, calculating wherein n-th pair of match point is correct matched posterior probability pnThere is following posterior probability mathematical modulo
Type,
Wherein, γ and σ is model parameter, and e is mathematics constant, and b is preset coefficient;
Parametric solution module, for according to point set X={ x1,…,xN}TWith Y={ y1,…,yN}TSolving model parameter, packet
Following submodule is included,
Neighbours' match point submodule, for being each match point xn, n=1 ..., N search for K nearest neighbours respectively
Match point, K take preset value;
Weight matrix submodule is solved for the search result according to neighbours' match point submodule using least square method
Dimension is the weight matrix W of N × N;
Optimization submodule is used for by optimal method solving model parameter s, R, o, γ, σ, including to place an order
Member,
Initialization unit, for enabling γ=γ0, R=I2×2, o=0, P=IN×N, γ0For the preset initial value of γ, order is worked as
Preceding the number of iterations k=1 calculates σ using following model parameter formula,
Wherein, matrix T=(t (x1),…,t(xN))T, tr () indicates to seek the mark of matrix;
Updating unit, for updating gained posterior probability mathematical model, meter in matrix P, including use model construction module
It is respectively correct matched posterior probability p to matching double points that calculation, which obtains N,1,…,pN, enable P=diag (p1,…,pN), diag is indicated
Diagonal matrix;
First parameter calculation unit, it is as follows for calculating parameter s, R, o,
Using following formula calculating parameter s,
Wherein, matrix
By IN×NOmission is denoted as I, matrix Q=(I-W)TP (I-W), λ are preset parameter;
Using following formula calculating parameter R,
R=UDVT
Wherein, D=diag (1, det (UVT)), the determinant of det () representing matrix, matrix U and V pass through singular value decomposition
It obtains;Using following formula calculating parameter o,
O=μy-sRμx
Second parameter calculation unit, parameter s, R, o for being calculated according to the first parameter calculation unit, is recalculated
Parameter γ, σ is as follows,
Using following formula calculating parameter γ,
σ is calculated using model parameter formula in initialization unit;
Iteration judging unit, for differentiating the condition of convergence, including calculating current parameter L, when meeting k=kmaxOr (L-
Lold)/Lold≤ ε terminates iteration, kmaxFor maximum number of iterations, ε is convergence threshold;Otherwise, k=k+1, order updating unit work
Make;The calculation formula of the parameter L is as follows,
Wherein, LoldIndicate the last L being calculated;
Judging result module, for calculating initial matching point to for correct matched posterior probability, and according to threshold decision
For initial matching point to correcting errors, realization is as follows,
The model parameter solved in the optimization submodule is substituted into posterior probability described in model construction module
Mathematical model, it is correct matched posterior probability that n-th pair of matching double points, which is calculated,;Work as pnWhen >=threshold, then it is assumed that the
N is correctly to match to match point;Work as pnWhen < threshold, then it is assumed that n-th pair of match point is the matching of mistake, wherein
Threshold is preset judgment threshold.
Moreover, weight matrix submodule include with lower unit,
Initial assignment unit, for working as match point xjIt is not the match point x searched in neighbours' match point submodulei
K neighbours' match point for the moment, then by WijIt is set as 0, wherein match point xjWith match point xiFor the match point in point set X,
And i, j=1 ..., N, WijIndicate the element of weight matrix W the i-th row jth column;
Unit is solved, is used forConstraint condition under, solve to obtain using least square method so that following
Cost function E (W) gets the weight matrix W of minimum value, and cost function E (W) is as follows,
The invention has the following advantages that
1, the present invention proposes a kind of unified maximum likelihood frame for Image Feature Matching.With the parameter generally used
Model is compared, and this frame can handle nonparametric model situation, and application range is wider.
2, the present invention constructs a kind of constraint of local geometric and optimizes to transformation model.This constraint saves adjacent spy
Partial structurtes between sign point, therefore can be used to the case where handling containing a large amount of erroneous matchings, there is stronger robustness.
Specific embodiment
Technical solution of the present invention is further described below by embodiment.
Method proposed by the present invention carries out mathematical modeling to image to be matched rigid transformation first, then preliminary by removal
Correct matching is established in the matching for the mistake established in a series of matching double points.This method utilizes the Bayes with hidden variable
Maximal possibility estimation carries out mathematical modeling.Meanwhile a kind of geometrical constraint for retaining partial structurtes between adjacent characteristic point has also been constructed,
Even if still keeping good robustness there are in the case where a large amount of erroneous matchings in preliminary matches.
Institute of embodiment of the present invention providing method mainly includes 3 steps:
Step 1, establishing the corresponding model of geometric transformation and matching double points between image to be matched is that correct matched posteriority is general
The corresponding model of rate;
For the rigid geometric transformation between image to be matched, it is as follows to establish transformation mathematical model:
Y=t (x)=sRx+o
Wherein, if two width image to be matched are image a and image b, x and y are the seat of pixel on image a and image b respectively
Vector is marked, t (x) indicates that rigid geometric transform relation, s indicate the dimension scale between image to be matched, and R is one 2 × 2 square
Battle array indicates the rotation between image to be matched, and o is one 2 × 1 matrix, indicates the translation between image to be matched;
Due to inevitably wrong, the present invention using matching double points obtained by images match in the prior art progress initial matching
Purpose be to remove to wherein mistake, then for point set on known one group of initial matching point centering image a be X=
{x1,…,xN}T, corresponding point set is Y={ y on image b1,…,yN}T, midpoint x1Corresponding matching point y1, and so on, point xNIt is right
Answer match point yN, comprising N to initial matching point pair, wherein n-th pair of matching double points is correct matched posterior probability pnIt can be by such as
Lower posterior probability mathematical model is calculated:
Wherein, γ and σ is model parameter, and e is mathematics constant, and coefficient b can be preassigned by those skilled in the art, or
Person uses variable element, and embodiment is using 2/5, i.e.,
Step 2, according to known initial matching point pair, i.e. point set X={ x1,…,xN}T, Y={ y1,…,yN}T, solve institute
The parameter of two models in step 1 is stated, includes following sub-step:
It step 2.1, is each match point xn, the search of k-d tree association search method and its is respectively adopted in n=1 ..., N
K nearest neighbours' match point;When it is implemented, those skilled in the art can voluntarily preset the value of K, K is taken in the present embodiment
15;
Step 2.2, according to the search result of the step 2.1, least square method is used to solve dimension as the weight of N × N
Matrix W;
In embodiment, weight matrix W solution is as follows,
Step 2.2.1, as match point xjIt is not the match point x searched in the step 2.1iK neighbours' match point it
For the moment, then by WijIt is set as 0, wherein match point xjWith match point xiFor the match point in point set X, and i, j=1 ..., N, WijTable
Show the element of weight matrix W the i-th row jth column;
Step 2.2.2,Constraint condition under, solve to obtain using least square method so that following generations
Valence function E (W) gets the weight matrix W of minimum value, and cost function E (W) is as follows:
Step 2.3, unknown mathematical model parameter: s, R, o, γ, σ is solved by optimal method;
The solution procedure of unknown mathematical model parameter s, R, o, γ, σ are as follows in embodiment:
Step 2.3.1, initiation parameter;Enable parameter γ=γ0(when it is implemented, those skilled in the art can be voluntarily
Set the initial value γ of γ0, embodiment takes γ0=0.9), matrix R=I2×2(i.e. dimension is 2 × 2, square of element all 1
Battle array), parameter o=0, matrix P=IN×N(i.e. dimension be N × N, element all 1 matrix), current iteration number k=1, use
Following model parameter formula calculate σ:
Wherein, matrix T=(t (x1),…,t(xN))T, tr () indicates to seek the mark of matrix;
Step 2.3.2 updates matrix P:
Using posterior probability mathematical model described in step 1, it is calculated the 1st ..., N is respectively correct to matching double points
Matched posterior probability p1,…,pN, enable P=diag (p1,…,pN), diag indicates diagonal matrix;
Step 2.3.3, calculating parameter s, R, o;
Using following formula calculating parameter s:
Wherein, each matrix
IN×1I.e. dimension be N × 1, element all 1 matrix, by IN×NOmission is denoted as I, matrix Q=(I-W)TP (I-W), wherein λ is
One preset parameter, those skilled in the art can preset value when specific implementation, take 100 in the present embodiment;
Using following formula calculating parameter R:
R=UDVT
Wherein, D=diag (1, det (UVT)), the determinant of det () representing matrix, matrix U and V pass through singular value decomposition
It obtains, formula is as follows:
Wherein, svd () indicates to carry out matrix singular value decomposition, and S is the result of singular value decomposition;
Using following formula calculating parameter o:
O=μy-sRμx
Step 2.3.4, parameter s, R, the o being calculated according to step 2.3.3 can recalculate ginseng based on current t (x)
Number γ, σ;Using following formula calculating parameter γ:
σ is calculated using model parameter formula described in step 2.3.1;
Step 2.3.5 differentiates the condition of convergence:
Current parameter L is calculated, when meeting k=kmaxOr (L-Lold)/Lold≤ ε terminates iteration;Otherwise, i.e. k < kmax
And (L-Lold)/Lold> ε, k=k+1 return to step 2.3.2, when it is implemented, those skilled in the art can free default maximum
The number of iterations kmaxValue, the value of the present embodiment is 50;
Wherein, ε is convergence threshold, and those skilled in the art can preset value when specific implementation, such as take 0.0001, Lold
Indicate that the last L for executing step 2.3.5 and being calculated can enable L when executing step 2.3.5 for the first timeoldIt is biggish for one
Initial value, such as 10 6 powers, execute can be used the calculated result that last time execution executes step 2.3.5 later.The calculating of L
Formula is as follows:
Step 3, initial matching point is calculated to for correctly matched posterior probability, and according to threshold decision initial matching point pair
Correct errors;
The parameter solved in the step 2.3 is substituted into posterior probability mathematical model described in step 1, is calculated n-th
It is correct matched posterior probability to matching double points;Work as pnWhen >=threshold, then it is assumed that n-th pair of match point is correctly to match;
Work as pnWhen < threshold, then it is assumed that n-th pair of match point is the matching of mistake, and wherein threshold is judgment threshold, specific real
Shi Shi, those skilled in the art can free default judgment threshold value, take 0.5 in the present embodiment.
When it is implemented, software mode, which can be used, in the above process realizes automatic running.It can also be mentioned using modular mode
For corresponding system, the embodiment of the present invention correspondingly provides a kind of Image Feature Matching based on local linear migration and rigid model
System comprises the following modules,
Model construction module is correct for establishing the corresponding model of geometric transformation and matching double points between image to be matched
The corresponding model of the posterior probability matched, realization is as follows,
For the rigid geometric transformation between image to be matched, foundation transformation mathematical model is as follows,
Y=t (x)=sRx+o
Wherein, if two width image to be matched are image a and image b, x and y are the seat of pixel on image a and image b respectively
Vector is marked, t (x) indicates that rigid geometric transform relation, s indicate the dimension scale between image to be matched, and R is one 2 × 2 square
Battle array indicates the rotation between image to be matched, and o is one 2 × 1 matrix, indicates the translation between image to be matched;
If known one group of initial matching point centering, point set is X={ x on image a1,…,xN}T, corresponding point set on image b
For Y={ y1,…,yN}T, calculating wherein n-th pair of match point is correct matched posterior probability pnThere is following posterior probability mathematical modulo
Type,
Wherein, γ and σ is model parameter, and e is mathematics constant, and b is preset coefficient;
Parametric solution module, for according to point set X={ x1,…,xN}TWith Y={ y1,…,yN}TSolving model parameter, packet
Following submodule is included,
Neighbours' match point submodule, for being each match point xn, n=1 ..., N search for K nearest neighbours respectively
Match point, K take preset value;
Weight matrix submodule is solved for the search result according to neighbours' match point submodule using least square method
Dimension is the weight matrix W of N × N;
Optimization submodule is used for by optimal method solving model parameter s, R, o, γ, σ, including to place an order
Member,
Initialization unit, for enabling γ=γ0, R=I2×2, o=0, P=IN×N, γ0For the preset initial value of γ, order is worked as
Preceding the number of iterations k=1 calculates σ using following model parameter formula,
Wherein, matrix T=(t (x1),…,t(xN))T, tr () indicates to seek the mark of matrix;
Updating unit, for updating gained posterior probability mathematical model, meter in matrix P, including use model construction module
It is respectively correct matched posterior probability p to matching double points that calculation, which obtains N,1,…,pN, enable P=diag (p1,…,pN), diag is indicated
Diagonal matrix;
First parameter calculation unit, it is as follows for calculating parameter s, R, o,
Using following formula calculating parameter s,
Wherein, matrix
By IN×NOmission is denoted as I, matrix Q=(I-W)TP (I-W), λ are preset parameter;
Using following formula calculating parameter R,
R=UDVT
Wherein, D=diag (1, det (UVT)), the determinant of det () representing matrix, matrix U and V pass through singular value decomposition
It obtains;Using following formula calculating parameter o,
O=μy-sRμx
Second parameter calculation unit, parameter s, R, o for being calculated according to the first parameter calculation unit, is recalculated
Parameter γ, σ is as follows,
Using following formula calculating parameter γ,
σ is calculated using model parameter formula in initialization unit;
Iteration judging unit, for differentiating the condition of convergence, including calculating current parameter L, when meeting k=kmaxOr (L-
Lold)/Lold≤ ε terminates iteration, kmaxFor maximum number of iterations, ε is convergence threshold;Otherwise, k=k+1, order updating unit work
Make;The calculation formula of the parameter L is as follows,
Wherein, LoldIndicate the last L being calculated;
Judging result module, for calculating initial matching point to for correct matched posterior probability, and according to threshold decision
For initial matching point to correcting errors, realization is as follows,
The model parameter solved in the optimization submodule is substituted into posterior probability described in model construction module
Mathematical model, it is correct matched posterior probability that n-th pair of matching double points, which is calculated,;Work as pnWhen >=threshold, then it is assumed that the
N is correctly to match to match point;Work as pnWhen < threshold, then it is assumed that n-th pair of match point is the matching of mistake, wherein
Threshold is preset judgment threshold.
Further, weight matrix submodule include with lower unit,
Initial assignment unit, for working as match point xjIt is not the match point x searched in neighbours' match point submodulei
K neighbours' match point for the moment, then by WijIt is set as 0, wherein match point xjWith match point xiFor the match point in point set X,
And i, j=1 ..., N, WijIndicate the element of weight matrix W the i-th row jth column;
Unit is solved, is used forConstraint condition under, solve to obtain using least square method so that following
Cost function E (W) gets the weight matrix W of minimum value, and cost function E (W) is as follows,
RANSAC, ICF, GS method of selection and the present invention carry out the comparison of images match.Comparing result such as following table, wherein just
True rate refer to be in matching double points that method finally provides correct matching double points ratio;Missing rate refers to method in screening process
The middle ratio for correct matching double points being judged as error matching points pair.It can be seen that this method used time is most short, accuracy rate highest is lost
Leak rate is minimum.
Method Contrast on effect table
Method | Time (second) | Accuracy | Missing rate |
RANSAC | 16.32 | 81.38% | 1.36% |
ICF | 2.13 | 91.27% | 18.39% |
GS | 0.98 | 70.95% | 20.97% |
The present invention | 0.34 | 98.7% | 0.87% |
Specific embodiment described herein is only an example for the spirit of the invention.The neck of technology belonging to the present invention
The technical staff in domain can make various modifications or additions to the described embodiments or be substituted using similar fashion,
However, it does not deviate from the spirit of the invention or beyond the scope of the appended claims.
Claims (4)
1. a kind of Image Feature Matching method based on local linear migration and rigid model, it is characterised in that: including following step
Suddenly,
Step 1, establishing the corresponding model of geometric transformation and matching double points between image to be matched is correct matched posterior probability phase
The model answered, realization is as follows,
For the rigid geometric transformation between image to be matched, foundation transformation mathematical model is as follows,
Y=t (x)=sRx+o
Wherein, if two width image to be matched be image a and image b, x and y be respectively pixel on image a and image b coordinate to
Amount, t (x) indicate that rigid geometric transform relation, s indicate the dimension scale between image to be matched, and R is one 2 × 2 matrix, table
Show the rotation between image to be matched, o is one 2 × 1 matrix, indicates the translation between image to be matched;
If known one group of initial matching point centering, point set is X={ x on image a1,…,xN}T, corresponding point set is Y on image b
={ y1,…,yN}T, calculating wherein n-th pair of match point is correct matched posterior probability pnThere is following posterior probability mathematical model,
Wherein, γ and σ is model parameter, and e is mathematics constant, and b is preset coefficient;
Step 2, according to point set X={ x1,…,xN}TWith Y={ y1,…,yN}TSolving model parameter, including following sub-step,
It step 2.1, is each match point xn, n=1 ..., N search for K nearest neighbours' match point respectively, and K takes preset value;
Step 2.2, according to the search result of step 2.1, least square method is used to solve dimension as the weight matrix W of N × N;
Step 2.3, by optimal method solving model parameter s, R, o, γ, σ, including following sub-step,
Step 2.3.1, initialization, including enable γ=γ0, R=I2×2, o=0, P=IN×N, γ0For the preset initial value of γ, enable
Current iteration number k=1 calculates σ using following model parameter formula,
Wherein, matrix T=(t (x1),…,t(xN))T, tr () indicates to seek the mark of matrix;
Step 2.3.2 updates matrix P, including using gained posterior probability mathematical model in step 1, N is calculated to match point
To respectively correct matched posterior probability p1,…,pN, enable P=diag (p1,…,pN), diag indicates diagonal matrix;
Step 2.3.3, calculating parameter s, R, o are as follows,
Using following formula calculating parameter s,
Wherein, matrix
By IN×NOmission is denoted as I, matrix Q=(I-W)TP (I-W), λ are preset parameter;
Using following formula calculating parameter R,
R=UDVT
Wherein, D=diag (1, det (UVT)), the determinant of det () representing matrix, matrix U and V are obtained by singular value decomposition
?;Using following formula calculating parameter o,
O=μy-sRμx
Step 2.3.4, parameter s, R, the o being calculated according to step 2.3.3, recalculate that parameter γ, σ is as follows, and use is following
Formula calculating parameter γ,
σ is calculated using model parameter formula in step 2.3.1;
Step 2.3.5 differentiates the condition of convergence, including calculating current parameter L, when meeting k=kmaxOr (L-Lold)/Lold≤
ε terminates iteration, kmaxFor maximum number of iterations, ε is convergence threshold;Otherwise, k=k+1, return step 2.3.2;The parameter L
Calculation formula it is as follows,
Wherein, LoldIndicate the last L being calculated;
Step 3, initial matching point is calculated to for correctly matched posterior probability, and just according to threshold decision initial matching point pair
Accidentally, realization is as follows,
The model parameter solved in the step 2.3 is substituted into posterior probability mathematical model described in step 1, is calculated n-th
It is correct matched posterior probability to matching double points;Work as pnWhen >=threshold, then it is assumed that n-th pair of match point is correctly to match;
Work as pnWhen < threshold, then it is assumed that n-th pair of match point is the matching of mistake, and wherein threshold is preset judgment threshold.
2. the Image Feature Matching method according to claim 1 based on local linear migration and rigid model, feature exist
In: step 2.2 includes following sub-step,
Step 2.2.1, as match point xjIt is not the match point x searched in the step 2.1iOne of K neighbours' match point
When, then by WijIt is set as 0, wherein match point xjWith match point xiFor the match point in point set X, and i, j=1 ..., N, WijIt indicates
The element of weight matrix W the i-th row jth column;
Step 2.2.2,Constraint condition under, solve to obtain using least square method so that following cost letters
Number E (W) gets the weight matrix W of minimum value, and cost function E (W) is as follows,
3. a kind of Image Feature Matching system based on local linear migration and rigid model, it is characterised in that: including with lower die
Block,
Model construction module is correct matched for establishing the corresponding model of geometric transformation and matching double points between image to be matched
The corresponding model of posterior probability, realization is as follows,
For the rigid geometric transformation between image to be matched, foundation transformation mathematical model is as follows,
Y=t (x)=sRx+o
Wherein, if two width image to be matched be image a and image b, x and y be respectively pixel on image a and image b coordinate to
Amount, t (x) indicate that rigid geometric transform relation, s indicate the dimension scale between image to be matched, and R is one 2 × 2 matrix, table
Show the rotation between image to be matched, o is one 2 × 1 matrix, indicates the translation between image to be matched;
If known one group of initial matching point centering, point set is X={ x on image a1,…,xN}T, corresponding point set is Y on image b
={ y1,…,yN}T, calculating wherein n-th pair of match point is correct matched posterior probability pnThere is following posterior probability mathematical model,
Wherein, γ and σ is model parameter, and e is mathematics constant, and b is preset coefficient;
Parametric solution module, for according to point set X={ x1,…,xN}TWith Y={ y1,…,yN}TSolving model parameter, including with
Lower submodule,
Neighbours' match point submodule, for being each match point xn, n=1 ..., N search for nearest K neighbours matching respectively
Point, K take preset value;
Weight matrix submodule solves dimension using least square method for the search result according to neighbours' match point submodule
For the weight matrix W of N × N;
Optimization submodule, for by optimal method solving model parameter s, R, o, γ, σ, including with lower unit,
Initialization unit, for enabling γ=γ0, R=I2×2, o=0, P=IN×N, γ0For the preset initial value of γ, current change is enabled
Generation number k=1 calculates σ using following model parameter formula,
Wherein, matrix T=(t (x1),…,t(xN))T, tr () indicates to seek the mark of matrix;
Updating unit is calculated for updating gained posterior probability mathematical model in matrix P, including use model construction module
It is respectively correct matched posterior probability p to matching double points to N1,…,pN, enable P=diag (p1,…,pN), diag indicates diagonal
Matrix;
First parameter calculation unit, it is as follows for calculating parameter s, R, o,
Using following formula calculating parameter s,
Wherein, matrix
By IN×NOmission is denoted as I, matrix Q=(I-W)TP (I-W), λ are preset parameter;
Using following formula calculating parameter R,
R=UDVT
Wherein, D=diag (1, det (UVT)), the determinant of det () representing matrix, matrix U and V are obtained by singular value decomposition
?;Using following formula calculating parameter o,
O=μy-sRμx
Second parameter calculation unit, parameter s, R, o for being calculated according to the first parameter calculation unit, recalculates parameter
γ, σ are as follows,
Using following formula calculating parameter γ,
σ is calculated using model parameter formula in initialization unit;
Iteration judging unit, for differentiating the condition of convergence, including calculating current parameter L, when meeting k=kmaxOr (L-
Lold)/Lold≤ ε terminates iteration, kmaxFor maximum number of iterations, ε is convergence threshold;Otherwise, k=k+1, order updating unit work
Make;The calculation formula of the parameter L is as follows,
Wherein, LoldIndicate the last L being calculated;
Judging result module, for calculating initial matching point to for correct matched posterior probability, and it is initial according to threshold decision
Matching double points are corrected errors, and realization is as follows,
The model parameter solved in the optimization submodule is substituted into posterior probability mathematics described in model construction module
Model, it is correct matched posterior probability that n-th pair of matching double points, which is calculated,;Work as pnWhen >=threshold, then it is assumed that n-th pair
Match point is correctly to match;Work as pnWhen < threshold, then it is assumed that n-th pair of match point is the matching of mistake, wherein threshold
For preset judgment threshold.
4. the Image Feature Matching system according to claim 3 based on local linear migration and rigid model, feature exist
In: weight matrix submodule include with lower unit,
Initial assignment unit, for working as match point xjIt is not the match point x searched in neighbours' match point submoduleiK
Neighbours' match point a period of time, then by WijIt is set as 0, wherein match point xjWith match point xiFor the match point in point set X, and i, j
=1 ..., N, WijIndicate the element of weight matrix W the i-th row jth column;
Unit is solved, is used forConstraint condition under, solve to obtain using least square method so that following costs
Function E (W) gets the weight matrix W of minimum value, and cost function E (W) is as follows,
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CN104599277A (en) * | 2015-01-27 | 2015-05-06 | 中国科学院空间科学与应用研究中心 | Image registration method for area-preserving affine transformation |
CN104732546A (en) * | 2015-04-02 | 2015-06-24 | 西安电子科技大学 | Non-rigid SAR image registration method based on region similarity and local spatial constraint |
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Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
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CN104599277A (en) * | 2015-01-27 | 2015-05-06 | 中国科学院空间科学与应用研究中心 | Image registration method for area-preserving affine transformation |
CN104732546A (en) * | 2015-04-02 | 2015-06-24 | 西安电子科技大学 | Non-rigid SAR image registration method based on region similarity and local spatial constraint |
Non-Patent Citations (2)
Title |
---|
Robust Point Matching via Vector Field Consensus;Jiayi Ma ect.;《IEEE TRANSACTIONS ON IMAGE PROCESSING》;20140831;第23卷(第4期);第1706-1721页 * |
基于t分布混合模型的点集非刚性配准算法;周志勇 等;《光学 精密工程》;20130930;第21卷(第9期);第2405-2420页 * |
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