CN110148184A - The method and system of camera intrinsic parameter is solved based on pole and the relationship of polar curve - Google Patents
The method and system of camera intrinsic parameter is solved based on pole and the relationship of polar curve Download PDFInfo
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Abstract
The invention discloses a kind of method and systems that camera intrinsic parameter is solved based on pole and the relationship of polar curve.Method are as follows: obtain the scene image under different perspectives, calculate separately the picture of picture round where 5 points in each scene image, the center of circle, then the picture based on round picture and the center of circle, calculate the picture of round circular point.According to the definition and projective invariance of absolute conic, the intrinsic parameter of video camera is sought.System includes an image acquisition device and an arithmetic unit, and image capture device executes Image Acquisition movement, and arithmetic unit executes operation movement.Hardware configuration of the present invention is simple, to scene without strict demand.Operand of the invention has and substantially reduces compared to traditional approach, and precision is also greatly improved compared with traditional approach.
Description
Technical field
It is especially a kind of to solve bimirror folding using pole and the relationship of polar curve the present invention relates to computer vision field
Reflect the method and system of camera intrinsic parameter.
Background technique
Computer vision is a new subject, it is to perceive and understand the world using computer generation for human eye and brain.
Its appearance makes people more clearly see the world clearly, and obtains more details.Therefore, computer vision technique is also widely used
In every field.Video camera is the master tool in computer vision technique, and camera intrinsic parameter determines the inside of video camera
Structure.When scholar takes a video camera, in this case it is not apparent that its internal structure can only obtain two using the picture of video camera shooting
Image information is tieed up, to understand 3D object from two-dimensional image information, it must be understood that camera intrinsic parameter.Solve video camera internal reference
Several processes are referred to as camera calibration.
The visual field of traditional cameras is smaller, but with the fast development of Network Information, traditional cameras cannot
Meets the needs of people's from " can see " to " seeing wider ".This just puts forward new requirements to researcher and scholar, that is, allows into
As the visual field becomes larger.The appearance of catadioptric video camera solves this problem, it increases reflecting mirror before traditional cameras
Face, common mirror surface have: parabolic mirror surface, hyperboloidal mirror, oval mirror surface peace face mirror.Because plane catadioptric video camera
Production is simple, and cost is also relatively low, so many scholars carry out three-dimensionalreconstruction using plane catadioptric video camera.Carrying out three-dimensional
Before reconstruct, need to demarcate plane catadioptric video camera.
Traditional cameras is exactly a pinhole camera, using the geometrical relationship of element in scene, solves pinhole camera
Intrinsic parameter be a kind of common method.Document " A linear approach for determining intrinsic
Parametersand pose of cameras from rectangles ", (Wu F., Wang G., et al., Journal
Of Software, Vol.14, pp.703-712,2003) it proposes to obtain conllinear by two non-parallel rectangles on space plane
Four end points, obtain circular point further according to the property of harmonic conjugates, using circular point as with absolute conic picture
The constraint relationship solves camera intrinsic parameter.
Document " Planar catadioptric stereo:geometry and calibration ", (Gluckman
J.,Nayar S.,IEEE Computer Society Conference onComputer Vision,Vol.1,pp.1-18,
2002) binocular stereo vision effect is realized using single camera and two pieces of plane mirrors, mainly from geometrically research biplane folding
Reflecting system, and the relative position that two virtual cameras can be constrained by plane motion is demonstrated, it calculates to extremely several
Fundamental matrix in what, and estimate focal length.But this article is not discussed the internal reflection between bimirror, does not have yet
Have and plane mirror imaging principle is applied in camera calibration.Two pieces of plane mirrors and a pinhole camera form a biplane
There is multiple internal reflection, goes out in scene when the angle between two pieces of plane mirrors is that 0-90 is spent in mirror-lens system in two plane mirrors
Existing multiple views.Pole geometrical relationship between many document utilization profiles solves camera intrinsic parameter or carries out three-dimensionalreconstruction.
Document " Self-calibration of catadioptric camera with two planar mirrors
From silhouettes ", (Ying X., Peng K., et al., IEEE Transactions on Pattern
Analysis and Machine Intelligence, vol.35, no.5, pp.1206-1220,2013) it proposes to roll in plane
In reflecting system, camera intrinsic parameter is solved with two methods, first method is: using two parallel circles on as plane
The constraint relationship of the intersection point (end point) and absolute conic picture that project two associated straight lines of conic section solves video camera
Intrinsic parameter, but solution procedure needs to use 3 order polynomials, and calculation amount is larger；Second method is: utilizing three-dimensional space point
The invariance of position asks a little corresponding 2D is mono- to reflect, and the mono- corresponding feature vector of conjugation complex eigenvalue reflected of 2D is exactly circular point
Picture, further solves camera intrinsic parameter, needs seven views in this approach, this requires that existing between two plane mirrors
The shortcoming of internal reflection twice, this method is: seven views can block mutually, influence the precision of calibration.When two planes
When angle between mirror is that 60-80 is spent, occur five views between two plane mirrors, when the angle between two plane mirrors is 72 degree or so,
It will not be blocked mutually between five views.Document " Geometric properties of multiple reflections in
Cat dioptric camera with two planar mirrors ", (Ying X., Peng K., et al., IEEE
Computer Society Conference on Computer Vision and Pattern Recognition,
Vol.26, no.2, pp.1126-1132,2010) discuss the geometrical relationship of five views.Five views are divided into Odd Phases
Adjacent view to and even number adjacent view pair, the pact of fundamental matrix Yu mirror normal direction end point is established from the viewpoint of Epipolar geometry
Beam relationship, and in odd number adjacent view pair, the picture of circular point is found out according to the harmonic conjugates relationship of pole and circular point picture,
But the intrinsic parameter that video camera is not only used to pole relationship between two video cameras, it will also be appreciated that the relative position of two video cameras,
So process can be very complicated.
Document " Camera self-calibration based on circular points with two
Planar ", (Zhao Y., Zhang X., et al., Multimedia Tools and Applications, vol.75,
No.13, pp.7981-7997,2016) picture that circular point is found out using two methods, further according to circular point picture and video camera internal reference
Several the constraint relationships solves camera intrinsic parameter.The first is: the picture of circular point is found out according to the inference of Laguerre theorem；Second
Kind is: intersected using line at infinity with circle and finds out circular point, the picture of available circular point on as plane.This article,
It is that vanishing line is further obtained by harmonic conjugates Relation acquisition end point.This patent is obtained from pole and polar curve relationship
Vanishing line.
Document " Camera self-calibration from projection silhouettes of an object
In double planar mirrors ", (Zhao Y., Li Y., Journal of the Optical Society of
America A, vol.34, no.5, pp.696,2017) with three kinds of methods solve camera intrinsic parameters.The first is: utilizing pole
The relationship of point and polar curve, obtains the picture of circular point；Second is: using the infinite point property conllinear with circular point, obtaining circle
The picture of circling point；The third is: using the symmetry and harmonic conjugates of plane mirror imaging, obtaining orthogonal end point.Finally, using annulus
The picture of point or the constraint relationship of orthogonal end point and absolute conic picture, solve camera intrinsic parameter.
Five views in bimirror are regarded as and are moved in a circle.Using under circular motion, between profile
Pole geometrical relationship solves external parameters of cameras or three-dimensionalreconstruction.Document " Self- calibration of turntable
Sequences from silhouettes ", (Zhang H., Shao L., IEEE Transactions on Pattern
Analysis and Machine Intelligence, vol.31, no.1, pp.5-14,2009) it proposes in turntable sequence,
Image invariant is estimated by the polar tangent of a contour of object, according to image invariant, can accurately indicate basic square
Battle array, can also restore the picture of circular point, further use Laguerre theorem and restore rotation angle.Because when seeking the polar tangent of profile,
Need to know the coordinate of object, so there can be error.
The generally existing following problems of the scheme of above-mentioned document, i.e., high to the required precision of the arrangement of testing ground, test are grasped
Order of magnitude height, the computational accuracy for making data volume that is cumbersome, calculating are lower.
Summary of the invention
Goal of the invention of the invention is: in view of the above problems, providing one kind in bimirror mirror-lens system
Under, utilize the method for plane mirror imaging and pole and the relationship calibrating camera of polar curve.To be arranged by simple test, more
Simple calculating process calculates to degree of precision the intrinsic parameter of video camera.
The technical solution adopted by the invention is as follows:
A method of camera intrinsic parameter, including following below scheme are solved based on pole and the relationship of polar curve:
A. scene image of several width under different perspectives is obtained, the corresponding test scene of the scene image are as follows:
An object point is placed between two plane mirrors that angle is predetermined angular, forms test scene, under the test scene,
5 points: the object point and 4 catadioptric exit points in two plane mirrors are obtained, 5 points are inevitable in same circle
On；
B. it is directed to each width scene image, executes following steps B1-B3:
B1: extracting the characteristic point coordinate of scene image, according to the characteristic point coordinate of extracted scene image, calculates institute
The picture of circle where stating 5 points；
B2. the picture for calculating separately 5 points calculates the center of circle of the circle according to the picture of 5 points
Picture；
B3: the picture of picture and the center of circle based on the circle seeks the picture of two circular points of the circle；
C. the picture according to the circular point to taking-up required by all scene images is based on projective invariance, seeks video camera
Intrinsic parameter.
Further, in step B1, according to the characteristic point coordinate of extracted scene image, 5 points are calculated
The picture of place circle specifically:
It is fitted using characteristic point coordinate of the least square method to the extracted scene image, obtained secondary song
Line is the picture of circle where 5 points.
Further, in step B2, according to the picture of 5 points, the picture in the center of circle of the circle is calculated specifically:
First calculate separately the picture of 5 points, then calculate separately each point picture about the circle picture polar curve, then
Coordinate of the picture based on part or all of each point about the intersection point between the polar curve of round picture, calculates the picture in the center of circle.
Further, seat of the above-mentioned picture based on part or all of each point about the intersection point between the polar curve of round picture
Mark, calculates the picture in the center of circle specifically:
If 5 points are respectively as follows: catadioptric exit point A1 of object point A0, A0 in plane mirror Π 1, A0 is in plane mirror
Catadioptric exit point A3, the A1 of catadioptric exit point A2, A2 in plane mirror Π 1 in the Π 2 catadioptric exit point A4,5 in plane mirror Π 2
The corresponding picture of point is respectively a0, a1, a2, a3, a4；
Take a0 about the polar curve and a1, a2 of the picture of the circle about two intersection points m, s between the polar curve of the picture of the circle；
A1 is taken, about the intersection point t between the polar curve of the picture of the circle, to take a2 about the picture of the circle about the polar curve and a4 of the picture of the circle
Polar curve and a3 about the intersection point n between the polar curve of the picture of the circle；Calculate the intersection point of straight line mn and straight line st again up to the center of circle
Picture.
Further, above-mentioned B3 specifically:
Seek the polar curve L of the picture in the center of circle about the picture of the circle, then seek the polar curve L and the circle picture two
Intersection point is the picture of two circular points of the circle.
Further, above-mentioned C specifically:
It is fitted using picture of the least square method to acquired all circular points, obtains the picture w of absolute conic,
W is decomposed into w=K-TK-1And Cholesky decomposition is carried out, obtain K-1, the calculated matrix K of institute of inverting is inside video camera
Parameter matrix extracts the intrinsic parameter that the parameter in the intrinsic parameters of the camera matrix had both obtained video camera respectively.
Further, scene image acquired in above-mentioned steps A is at least 3 width.
Further, the angle of above-mentioned two plane mirror is 70-75 degree.
The present invention also provides a kind of system for solving camera intrinsic parameter based on pole and the relationship of polar curve, the system packets
Include an image acquisition device and an arithmetic unit；Described image collector is for acquiring image and by the image transmitting of acquisition to the fortune
Calculate device；The system runs the above-mentioned method for solving camera intrinsic parameter based on pole and the relationship of polar curve, wherein described image
Collector is used to execute the above-mentioned scene image solved in the method for camera intrinsic parameter based on pole and the relationship of polar curve and acquired
Movement, the arithmetic unit are used to execute the above-mentioned operation solved in the method for camera intrinsic parameter based on pole and the relationship of polar curve
It acts and exports operation result.
In conclusion by adopting the above-described technical solution, the beneficial effects of the present invention are:
1, hardware configuration required for the present invention is very simple, it is only necessary to simply be set two plane mirrors and an object target
It sets, method and system of the invention can be run.For being arranged without too stringent limitation, for dimension of object for hardware facility
It is not also required with placement location.
2, in the present invention, 5 points will not overlap, therefore computational solution precision is very high.
3, calculating process of the invention is linear operation, can be with compared with 3 times or more polynomial solutions in traditional approach
Substantially reduce operand.
Detailed description of the invention
Examples of the present invention will be described by way of reference to the accompanying drawings, in which:
Fig. 1 is the schematic diagram for testing scene.
Fig. 2 is the schematic diagram of the picture of circle and the picture of circular point.
Specific embodiment
All features disclosed in this specification or disclosed all methods or in the process the step of, in addition to mutually exclusive
Feature and/or step other than, can combine in any way.
Any feature disclosed in this specification (including any accessory claim, abstract), unless specifically stated,
It is replaced by other equivalent or with similar purpose alternative features.That is, unless specifically stated, each feature is a series of
An example in equivalent or similar characteristics.
Using two pieces of rectangle plane mirror Π 1, Π 2 and an object build test scene, between two pieces of rectangle plane mirrors
Angle is adjusted to 72 degree, and object is as two plane mirror Π 1, and between the acute angle of Π 2, Π 1 in two plane mirrors, 2 work of Π occurs four
Each object simulation is point when concrete operation by a catadioptric object.Up to object point A0 and its four catadioptric exit points of generation
A1,A2,A3,A4.A1 is catadioptric exit point of the point A0 in plane mirror Π 1；A2 is catadioptric exit point of the point A0 in plane mirror Π 2；
A3 is catadioptric exit point of the point A2 in plane mirror Π 1；A4 is catadioptric exit point of the point A1 in plane mirror Π 2.Facts proved that 5
Point is on same circle, as shown in Figure 1.
Embodiment one
The method based on pole and the relationship of polar curve solution camera intrinsic parameter that present embodiment discloses a kind of, including it is following
Step:
A. from the image of multiple and different angle acquisitions test scene, 3 width scene images are therefrom selected；
B. step B1-B3 is executed to each width scene image:
B1: the coordinate of the characteristic point of scene image is extracted.In MATLAB software, it can be mentioned using Harris Corner Detection
Take the coordinate of image characteristic point.Least square method fitting is recycled, obtains the equation of conic section C, conic section C is 5
Circle is as the picture in plane where a point；
B2: the picture in the center of circle is sought.As shown in Figure 1, according to the symmetry of plane mirror imaging, an object point A0 and its generation
Four catadioptric exit point A1, A2, A3, A4 on the same circle.As shown in Fig. 2, the picture of the circle is secondary for one on as plane
The equation of curve C, conic section C are calculated by the mode of step 1；Five points A0, A1, A2, A3, A4 are as the picture in plane
It is corresponding are as follows: the picture of each point can be obtained by the Harris Corner Detection in MATLAB in a0, a1, a2, a3, a4.Point a0 is closed
Intersect at point m about the polar curve of conic section C in the polar curve and point a1 of conic section C, point a2 about conic section C polar curve and
Point a3 intersects at point n about the polar curve of conic section C, point a0 about conic section C polar curve and point a2 about conic section C's
Polar curve intersects at point s, and point a1 intersects at point t about the polar curve of conic section C about the polar curve and point a4 of conic section C.According to
Match Principle for Extreme Nodes and Lines in projective geometry, straight line a0a1 are the polar curves of point m, and straight line a2a3 is the polar curve of point n.Because point a0 and point a1 is closed
Symmetrical in plane mirror Π 1, point a2 and point a3 are symmetrical about plane mirror Π 1, therefore straight line a0a1 gives one to disappear with straight line a2a3 phase
Point is lost, if straight line a0a1 and straight line a2a3 intersect at end point r1.Because end point r1 is not only on the polar curve of point m, but also point n's
On polar curve, according to the match Principle for Extreme Nodes and Lines in projective geometry, so point m and point n on the polar curve of end point r1, i.e. straight line mn passes through
The picture o in the center of circle.Similarly, straight line st also passes through the picture o in the center of circle.
It can be passed through by a0, a1 and conic section C in the hope of point m by a2, a3 and conic section C in the hope of point n
A0, a2 and conic section C can be in the hope of point s, can be in the hope of point t by a2, a4 and conic section C.It indicates are as follows:
M=(Ca0) × (Ca1)；……………………………………………(1)
Wherein, "×" indicates the intersection point of two straight lines, and " " indicates dot product.
N=(Ca2) × (Ca3)；……………………………………………(2)
S=(Ca0) × (Ca2)；……………………………………………(3)
T=(Ca1) × (Ca4)；……………………………………………(4)
Since straight line mn and straight line st are by the picture o in the center of circle, then the picture o in the center of circle is acquired are as follows:
O=(m × n) × (s × t)；……………………………………………(5)
Wherein, " m × n " indicates to pass through the straight line of point m and n, and " s × t " indicates to pass through the straight line of point s and t, " () × () "
Indicate the intersection point of two straight lines.
B3: as shown in Fig. 2, according to the match Principle for Extreme Nodes and Lines in the definition and projective geometry of pole and polar curve, the picture o in the center of circle about
The polar curve of conic section C is vanishing line L.The back projection of conic section C is circle O, because each circle passes through two circular points
I, J, and circular point is the conjugation complex point of infinite point, and coordinate is (1, i, 0), (1 ,-i, 0), i expression plural number.According to penetrating
Two intersection points of shadow invariance, vanishing line L and conic section C are the picture mI, mJ of two circular points.
The center of circle as o about the polar curve of conic section C is vanishing line L:
L=Co；………………………………………………………………(6)
" " indicates dot product.
Vanishing line L and conic section C intersects at the picture mI, mJ of two circular points:
MI=L × C,
MJ=L × C；………………………………………………………………(7)
"×" indicates that straight line intersects with conic section, it should be noted that mI and mJ is that two-phase symmetrically puts picture.
C. by the B that repeats the above steps (B1-B3), the picture of totally 6 pairs of circular points of 3 width scene images: { m is obtainediI, miJ}
(i=1,2,3), according to the definition of absolute conic, circular point is on absolute conic, according to projective invariance, annulus
Picture w=K of the picture of point in absolute conic-TK-1On, after the picture for obtaining six circular points, it is fitted, is obtained with least square method
The picture w of absolute conic, carries out Cholesky decomposition to w, then inverts, so that it may camera intrinsic parameter matrix K is solved,
The intrinsic parameter that the parameter in the camera intrinsic parameter matrix had both obtained video camera is extracted respectively.
Embodiment two
Referring to Fig. 1-2, present embodiment discloses a kind of sides that camera intrinsic parameter is solved based on pole and the relationship of polar curve
The test scene of method, the present embodiment is as shown in Figure 1.
1, several experimental images of target are shot from different perspectives with pinhole camera, choose three width, read in image,
In MATLAB software, using Harris Corner Detection, the coordinate of image characteristic point is extracted.
The homogeneous coordinates matrix of characteristic point on piece image are as follows:
A10=[- 298.46807819006-1710.74460462943 1.00000000000]T, (8)
A11=[1518.58011758885 3115.25672794354 1.00000000000]T, (9)
A12=[631.74131830283-1155.32204715820 1.00000000000]T, (10)
A13=[290.27515513292 1288.08570300676 1.00000000000]T, (11)
A14=[- 1548.37594112322 3680.42383321465 1.00000000000]T, (12)
The homogeneous coordinates matrix of characteristic point on second width image are as follows:
a20=[- 206.05814551994 308.77764521780 1.00000000000]T, (13)
a21=[205.89211208267 503.13717652655 1.00000000000]T, (14)
a22=[- 104.83114909059-303.87222366040 1.00000000000]T, (15)
a23=[505.13928276347 260.60432842996 1.00000000000]T, (16)
a24=[454.72156520090-202.68034265175 1.00000000000]T。 (17)
The homogeneous coordinates matrix of characteristic point on third width image are as follows:
a30=[94.05521740220 216.31847128776 1.00000000000]T, (18)
a31=[382.20357517076 481.14176348368 1.00000000000]T, (19)
a32=[782.04083280012-721.19646569407 1.00000000000]T, (20)
a33=[793.17204254048 387.93183774150 1.00000000000]T, (21)
a34=[1293.63956200025 112.80871193735 1.00000000000]T。 (22)
Using least square method, the coefficient matrix for being fitted obtained conic section to each width image respectively is distinguished
Are as follows:
2, the picture in the center of circle is sought
Bring formula (8)-(12) and (23) into the center of circle on formula (1)-available piece image of (5) formula homogeneous as o1
Coordinates matrix:
o1=[838.03439162024 18017.76057123258 1.00000000000]T。 (26)
Bring formula (13)-(17) and (24) into the center of circle on formula (1)-available second width image of (5) formula neat as o2
Secondary coordinates matrix:
o2=[208.33386598732 160.11921237930 1.00000000000]T。 (27)
Above (18)-(22) and (25) are brought into the neat as o3 of the center of circle on the available third width image of (1)-(5) formula
Secondary coordinates matrix:
o3=[620.20063849585 214.91836458674 1.00000000000]T。 (28)
3, the picture of circular point is obtained
(23) and (26) are brought into (6), (7) formula obtains two circular points on piece image as m1I, and m1J's is homogeneous
Coordinates matrix are as follows:
m1I=[308.9335078-574.1052598i 198.1247238-194.7858296i 1]T, (29)
m1J=[308.9335078+574.1052598i 198.1247238+194.7858296i 1]T。 (30)
(24) and (27) are brought into (6), (7) formula obtains two circular points on the second width image as m2I, and m2J's is homogeneous
Coordinates matrix are as follows:
m2I=[1099.0464768+1056.1763532i 1276.2903427-975.9245900i 1]T, (31)
m2J=[1099.0464768-1056.1763532i 1276.2903427+075.9245900i 1]T。 (32)
(25) and (28) are brought into (6), (7) formula obtains two circular points on third width image as m3I, and m3J's is homogeneous
Coordinates matrix are as follows:
m3I=[395.1983773+869.7375564i 929.4786350-143.0723642i 1]T, (33)
m3J=[395.1983773-869.7375564i 9294786350+143.0723642i 1]T。 (34)
4, camera intrinsic parameter is solved
(29)-(34) formula is fitted with least square method, obtains the picture w=K of absolute conic-TK-1Coefficient
Matrix, as a result are as follows:
Cholesky decomposition is carried out to (35), then is inverted, so that it may w is obtained, as a result as follows:
From (36) Shi Ke get, five intrinsic parameters of video camera are respectively as follows: the effective focal length of u axis direction: fu=
600.00000000015；The effective focal length of v axis direction: fv=660.00000000020；Obliquity factor: s=
0.09999999987；U0=300.00000000015；V0=230.00000000008, i.e. principal point homogeneous coordinates matrix are as follows: P
=[300.00000000015 230.00000000008 1.00000000000]T。
Embodiment three
Present embodiment discloses a kind of system for solving camera intrinsic parameter based on pole and the relationship of polar curve, based on by
The test scene that two plane mirrors, an object point are built, two plane mirrors are placed in two plane mirrors at 72 degree or so angles, by object point
Acute angle between.The system includes an image acquisition device and an arithmetic unit, the data output end two and arithmetic unit of image acquisition device
Data input pin, in one embodiment, image acquisition device select pinhole cameras.System operation is based on pole and polar curve
The method of relationship solution camera intrinsic parameter, wherein image acquisition device is asked for executing the above-mentioned relationship based on pole and polar curve
The scene image acquisition movement in the method for camera intrinsic parameter is solved, above-described embodiment is matched with, under 3 width different perspectivess of acquisition
Scene image, and be transmitted to arithmetic unit；For executing, execution is above-mentioned to be solved arithmetic unit based on pole and the relationship of polar curve
Operation in the method for camera intrinsic parameter acts and exports operation result, i.e., B and later step in execution method and step.
The invention is not limited to specific embodiments above-mentioned.The present invention, which expands to, any in the present specification to be disclosed
New feature or any new combination, and disclose any new method or process the step of or any new combination.
Claims (9)
1. a kind of method for solving camera intrinsic parameter based on pole and the relationship of polar curve, which is characterized in that including following below scheme:
A. scene image of several width under different perspectives is obtained, the corresponding test scene of the scene image are as follows:
An object point is placed between two plane mirrors that angle is predetermined angular, is formed test scene and is obtained under the test scene
5 points: the object point and 4 catadioptric exit points in two plane mirrors, 5 points are inevitable on same circle；
B. it is directed to each width scene image, executes following steps B1-B3:
B1: extracting the characteristic point coordinate of scene image, according to the characteristic point coordinate of extracted scene image, calculates described 5
The picture of circle where a point；
B2. the picture for calculating separately 5 points calculates the picture in the center of circle of the circle according to the picture of 5 points；
B3: the picture of picture and the center of circle based on the circle seeks the picture of two circular points of the circle；
C. the picture according to the circular point to taking-up required by all scene images is based on projective invariance, seeks the internal reference of video camera
Number.
2. the method for solving camera intrinsic parameter based on pole and the relationship of polar curve as described in claim 1, which is characterized in that
In the B1, according to the characteristic point coordinate of extracted scene image, the picture of circle where 5 points is calculated specifically:
It is fitted using characteristic point coordinate of the least square method to the extracted scene image, obtained conic section is i.e.
For the picture of circle where 5 points.
3. the method for solving camera intrinsic parameter based on pole and the relationship of polar curve as described in claim 1, which is characterized in that
In the B2, according to the picture of 5 points, the picture in the center of circle of the circle is calculated specifically:
The picture of 5 points is first calculated separately, then calculates separately the polar curve of the picture of each point about the picture of the circle, then is based on
Coordinate of the picture of part or all of each point about the intersection point between the polar curve of round picture, calculates the picture in the center of circle.
4. the method for solving camera intrinsic parameter based on pole and the relationship of polar curve as claimed in claim 3, which is characterized in that
Coordinate of the picture based on part or all of each point about the intersection point between the polar curve of round picture, calculates the center of circle
Picture specifically:
If 5 points are respectively as follows: catadioptric exit point A1 of object point A0, A0 in plane mirror 1, folding of the A0 in plane mirror 2
Catadioptric exit point A4,5 point corresponding picture of catadioptric exit point A3, the A1 of reflection point A2, A2 in plane mirror 1 in plane mirror 2
Respectively a0, a1, a2, a3, a4；
Take a0 about the polar curve and a1, a2 of the picture of the circle about two intersection points m, s between the polar curve of the picture of the circle；Take a1
The polar curve and a4 of picture about the circle take a2 about the pole of the picture of the circle about the intersection point t between the polar curve of the picture of the circle
Line and a3 are about the intersection point n between the polar curve of the picture of the circle；Calculate the intersection point of straight line mn and straight line st again up to the picture in the center of circle.
5. the method for solving camera intrinsic parameter based on pole and the relationship of polar curve as described in claim 1, which is characterized in that
The B3 specifically:
The polar curve L of the picture in the center of circle about the picture of the circle is sought, then seeks two intersection points of the picture of the polar curve L and the circle
The picture of two circular points of the as described circle.
6. the method for solving camera intrinsic parameter based on pole and the relationship of polar curve as described in claim 1, which is characterized in that
The C specifically:
It is fitted using picture of the least square method to acquired all circular points, the picture w of absolute conic is obtained, by w
It is decomposed into w=K-TK-1And Cholesky decomposition is carried out, obtain K-1, the calculated matrix K of institute of inverting is intrinsic parameters of the camera
Matrix extracts the intrinsic parameter that the parameter in the intrinsic parameters of the camera matrix had both obtained video camera respectively.
7. the method for solving camera intrinsic parameter based on pole and the relationship of polar curve as described in one of claim 1-6, special
Sign is that acquired scene image is at least 3 width in the step A.
8. the method for solving camera intrinsic parameter based on pole and the relationship of polar curve as described in one of claim 1-6, special
Sign is that the angle of two plane mirrors is 70-75 degree.
9. a kind of system for solving camera intrinsic parameter based on pole and the relationship of polar curve, the system include an image acquisition device and
One arithmetic unit；Described image collector is for acquiring image and by the image transmitting of acquisition to the arithmetic unit；It is characterized in that,
The system runs the side as described in one of claim 1-8 that camera intrinsic parameter is solved based on pole and the relationship of polar curve
Method, wherein described image collector is used to execute the above-mentioned method for solving camera intrinsic parameter based on pole and the relationship of polar curve
In scene image acquisition movement, the arithmetic unit above-mentioned solves video camera internal reference based on pole and the relationship of polar curve for executing
Operation in several methods acts and exports operation result.
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