CN109724623A

CN109724623A - A kind of two-dimensional calibrations method and device of mapping camera elements of interior orientation

Info

Publication number: CN109724623A
Application number: CN201811597198.0A
Authority: CN
Inventors: 远国勤; 郑丽娜; 张洪文; 丁亚林; 孙建军; 李彬; 张壮
Original assignee: Changchun Institute of Optics Fine Mechanics and Physics of CAS
Current assignee: Changchun Institute of Optics Fine Mechanics and Physics of CAS
Priority date: 2018-12-26
Filing date: 2018-12-26
Publication date: 2019-05-07
Anticipated expiration: 2038-12-26
Also published as: CN109724623B

Abstract

The invention relates to the technical field of aerial surveying and mapping, in particular to a two-dimensional calibration method and device for azimuth elements in a surveying and mapping camera. The calibration method and device use parallel light to illuminate the geometric center position of a linear array detector in a surveying and mapping camera to perform imaging, and record the change the azimuth and elevation angles of the surveying and mapping camera, until the parallel light is imaged in the linear array detector of the surveying and mapping camera again, and record the azimuth angle, elevation angle and linear array detection of the surveying and mapping camera at this time. The position coordinates of the image points in the imaging of the detector are calculated, and the inner azimuth elements of the surveying and mapping cameras are calculated according to the azimuth and pitch angles of the multiple surveying and mapping cameras and the position coordinates of the image points in the imaging of the line array detector. By adjusting the azimuth and pitch angles of the surveying and mapping cameras, the internal azimuth elements are calibrated to ensure that the star points are imaged in the same line array of the surveying and mapping cameras, and the precise calibration of the line-array surveying and mapping cameras is realized.

Description

A kind of two-dimensional calibrations method and device of mapping camera elements of interior orientation

Technical field

The present invention relates to aerial mapping technical fields, in particular to a kind of two dimension of mapping camera elements of interior orientation Scaling method and device.

Background technique

Linear array mapping camera has the advantages such as big base-height ratio, high-efficient, obtains in modern Aviation mapping and widely answers It needed before use with, linear array mapping camera to principal point, main carry out precision calibration away from elements of interior orientation such as, distortion.

Linear array mapping camera generally carries out elements of interior orientation calibration using precision angle method in laboratory, realizes this side The caliberating device of method include standard sources 1, light pipe holder 2, parallel light tube 3, mapping camera 4, camera support 5, precise rotating platform 6, Vibration-isolating platform 7, as shown in Figure 1, the star tester in single asterism hole is installed in 3 image planes of parallel light tube, for simulating single infinity Target.This method calibration principle is as shown in Figure 2: adjustment precise rotating platform 6, mapping camera 4, mutual between parallel light tube 3 first Relationship, when guaranteeing that precise rotating platform 6 is in zero-bit, asterism is imaged at the selected initial value M of CCD image planes, and M is generally taken as CCD picture The geometric center in face, O is the principal point to be asked of optical system, S in Fig. 2_xFor projection of the principal point in CCD image planes, OS_xFor wait ask main Away from x₀For principal point calibration value, f_xBased on away from calibration value, due to the influence of distortion, be located at true field angle α_iLocate asterism P_iImaging In focal plane P_i' place, according to geometric optics, α_iLocate P_iThe optical distortion Δ of light_iAre as follows: Δ_i=x_i-x₀-f_x×tan(α_i-dα)。 Change angle with precise rotating platform 6, obtains n asterism angle [alpha]₁,α₂,α₃...α_nAnd corresponding image point position x₁,x₂,x₃...x_n, with Observation point distortion quadratic sumMinimum constraint condition can solve principal point x according to least-squares algorithm₀, it is main away from f_x, distortion Δ_iEqual elements of interior orientation.Precision angle method has many advantages, such as that algorithm is direct, precision is higher, but there is also following problems:

1. this method is one-dimension calibration, need during the calibration process, all asterisms are imaged on the same of linear array detector In row pixel, need accurately leveling the positional relationship between turntable, camera and light pipe before calibration；

2. have biggish distortion in big visual field line-scan digital camera optical system, make linear array detector in image planes for pincushion or It is barrel-shaped, it will not be straight line, cause even if carrying out accurate adjustment to the relationship of turntable, camera and light pipe before calibration, also not May during the calibration process, in the case where not adjusting the elevation angle, asterism images in the same of linear array detector in entire visual field In row pixel, i.e. this method calibration for not being suitable for big visual field linear array mapping camera.

Summary of the invention

The embodiment of the invention provides a kind of two-dimensional calibrations method and devices of mapping camera elements of interior orientation, at least to solve Certainly technological deficiency when existing progress one-dimension calibration.

According to an embodiment of the invention, a kind of two-dimensional calibrations method of mapping camera elements of interior orientation is provided, including with Lower step:

Step b: being imaged using the geometric center position that directional light is radiated at linear array detector in mapping camera, record The azimuth of mapping camera and pitch angle at this time；

Step c: changing azimuth and the pitch angle of mapping camera, until directional light re-imaging is in the linear array of mapping camera Image point position coordinate in detector, in the record azimuth of mapping camera, pitch angle and linear array detector imaging at this time；

Step d: being repeated several times step c, obtains in azimuth, pitch angle and the linear array detector imaging of multiple mapping cameras Image point position coordinate；

Step e: according to the image point position coordinate in the imaging of the azimuth of multiple mapping cameras, pitch angle and linear array detector Calculate the elements of interior orientation of mapping camera.

Further, step e includes:

According to the image point position coordinate in the imaging of the azimuth of multiple mapping cameras, pitch angle and linear array detector, and make The elements of interior orientation of mapping camera is calculated using least square adjustment method with distortion quadratic sum minimum constraint condition.

Further, step c includes:

The azimuth for changing mapping camera, judges that can directional light be imaged in the linear array detector of mapping camera, if can, Image point position coordinate in the record azimuth of mapping camera, pitch angle and linear array detector imaging at this time；If cannot, change and surveys The pitch angle of camera is drawn, until directional light can be imaged in the linear array detector of mapping camera, record mapping camera at this time Image point position coordinate in azimuth, pitch angle and linear array detector imaging.

Further, method includes:

Step b: being imaged using the geometric center position that directional light is radiated at linear array detector in mapping camera, record The azimuth of mapping camera is set to zero by the pitch angle β of mapping camera at this time；

Step c: changing azimuth and the pitch angle of mapping camera, until directional light re-imaging is in the linear array of mapping camera Detector G₁Point position, records the azimuth angle alpha of mapping camera₁And pitch angle (β+d β₁), record G₁Point image point position coordinate G_1x；

Step d: step c is repeated several times, successively obtains G₂, G₃..., G_nPoint records the pitch angle (β+d of mapping camera β₂), (β+d β₃) ..., (β+d β_n) and azimuth angle alpha₂, α₃..., α_n, record G₂, G₃..., G_nImage point position coordinate G_2x, G_3x..., G_{n x}；

Step e: according to the image point position coordinate in the imaging of the azimuth of n mapping camera, pitch angle and linear array detector The elements of interior orientation of mapping camera is calculated, the integer that wherein n is >=1.

Further, photo coordinate system xNy and turntable coordinate system XOY is defined, x-axis is linear array spy in photo coordinate system Device length direction is surveyed, N is the intersection point in the online array detector of principal point, and X-axis is parallel with dimensional turntable pitch axis in turntable coordinate system, Y Axis is parallel with dimensional turntable azimuth axis, and mapping camera is mounted in dimensional turntable；When M point is that dimensional turntable is located at zero point, in parallel Picture point of the light pipe in linear array detector；

The transformational relation of plane coordinate system xNy and turntable coordinate system XOY are as follows:

M_O=C_N ^OM_N+T (15)

M in formula (1)_OFor M point in turntable coordinate system XOY coordinate, M_NFor M point in plane coordinate system xNy coordinate, M_OPoint x Coordinate is denoted as M_Ox, y-coordinate is denoted as M_Oy, C_N ^O2 × 2 spin matrixs converted for plane coordinate system xNy to turntable coordinate system XOY:

θ indicates the angle between linear array detector and dimensional turntable direction of rotation, formula (1) in formula (2) y₀It is principal point y to coordinate, G₁Point distortion can method for solving it is as follows: dimensional turntable is around its azimuth axis rotation alpha₁D is rotated further around pitch axis β₁When, the asterism of directional light subpoint in photo coordinate system xNy by M point is moved to G at this time₁Point, then in Rt Δ OO₁In S, It can be in the hope of:

F is the master of mapping camera away from M in formula (3)_OxFor M point in turntable coordinate system XOY x coordinate, M_OyIt is M point in turntable Y-coordinate in coordinate system XOY, SO₁For line segment SO₁Length；When d α is that parallel light tube turns to S point by M point, dimensional turntable is in side Position to rotational angle；

Then in Rt Δ O₁In SH:

SH indicates the length of line segment SH, H in formula (4)_OxFor point H in turntable coordinate system XOY x coordinate, H_OyTurning for M point Y-coordinate in platform coordinate system XOY；

After acquiring H point, in Rt Δ OKO₁、RtΔG₁KO₁In to G₁Point is solved:

O in formula (5)₁K indicates line segment O₁The length of K, G_1Ox、G_1OyRespectively G₁X, the y of point in turntable coordinate system XOY are sat Mark, can obtain according to formula (1):

G_N1=(C_N ^O)-¹(G_O1-T) (20)

(C in formula (6)_N ^O)^-1Representing matrix C_N ^OInverse matrix；G_N1For G₁In the coordinate of plane coordinate system xNy, x, y are sat point Mark is denoted as G respectively_N1xAnd G_N1y, then G can be obtained₁Point distortion are as follows:

DG in formula (7)_1xIndicate G point x to distortion, DG_1yIndicate G point y to distortion；In entire calibration process, G is obtained altogether₁, G₂, G₃..., G_nAmount to n calibration point, then basisMinimum constraint condition, using least square adjustment Method can acquire mapping camera principal point x₀、y₀, main away from f, distort Δ_i。

Further, the elements of interior orientation of mapping camera include principal point, it is main away from, distortion.

According to another embodiment of the present invention, a kind of two-dimensional calibrations device of mapping camera elements of interior orientation is provided, is wrapped It includes:

First recording unit, in the geometric center position for being radiated at linear array detector in mapping camera using directional light After being imaged, the azimuth of mapping camera and pitch angle at this time are recorded；

Second recording unit, for change mapping camera azimuth and pitch angle, until directional light re-imaging exists After in the linear array detector of mapping camera, record is at this time in the azimuth of mapping camera, pitch angle and linear array detector imaging Image point position coordinate；

Acquiring unit, the picture point in azimuth, pitch angle and linear array detector imaging for recording multiple mapping cameras Position coordinates；

Computing unit, for according to the picture point in the imaging of the azimuth of multiple mapping cameras, pitch angle and linear array detector Position coordinates calculate the elements of interior orientation of mapping camera.

Further, computing unit is used to be imaged according to the azimuth of multiple mapping cameras, pitch angle and linear array detector In image point position coordinate, and survey calculated using least square adjustment method using distortion quadratic sum minimum constraint condition Draw the elements of interior orientation of camera.

Further, the calculating step of computing unit are as follows:

Photo coordinate system xNy and turntable coordinate system XOY is defined, x-axis is that linear array detector is rectangular in photo coordinate system To N is the intersection point in the online array detector of principal point, and X-axis is parallel with dimensional turntable pitch axis in turntable coordinate system, Y-axis and two dimension Turntable azimuth axis is parallel, and mapping camera is mounted in dimensional turntable；When M point is that dimensional turntable is located at zero point, parallel light tube is online Picture point in array detector；

M_O=C_N ^OM_N+T (22)

Then in Rt Δ O₁In SH:

G_N1=(C_N ^O)^-1(G_O1-T) (27)

The two-dimensional calibrations method and device of one of embodiment of the present invention mapping camera elements of interior orientation, by adjusting survey Azimuth, the pitch angle progress elements of interior orientation calibration for drawing camera, guarantee that asterism is imaged in the same line battle array of mapping camera, Realize the precision calibration to linear array type mapping camera.The scaling method is simple, and when calibration does not need to parallel light tube, mapping phase Mutual alignment relation between machine, dimensional turntable accurately level.

Detailed description of the invention

The drawings described herein are used to provide a further understanding of the present invention, constitutes part of this application, this hair Bright illustrative embodiments and their description are used to explain the present invention, and are not constituted improper limitations of the present invention.In the accompanying drawings:

Fig. 1 is the schematic diagram of caliberating device in the prior art；

Fig. 2 is the schematic diagram for realizing Fig. 1 caliberating device；

Scaling method flow chart of the invention when Fig. 3；

Fig. 4 is the schematic diagram for realizing Fig. 3 scaling method；

Fig. 5 is the module map of caliberating device of the invention；

Fig. 6 is the schematic diagram of caliberating device of the invention.

Specific embodiment

In order to enable those skilled in the art to better understand the solution of the present invention, below in conjunction in the embodiment of the present invention Attached drawing, technical scheme in the embodiment of the invention is clearly and completely described, it is clear that described embodiment is only The embodiment of a part of the invention, instead of all the embodiments.Based on the embodiments of the present invention, ordinary skill people The model that the present invention protects all should belong in member's every other embodiment obtained without making creative work It encloses.

It should be noted that description and claims of this specification and term " first " in above-mentioned attached drawing, " Two " etc. be to be used to distinguish similar objects, without being used to describe a particular order or precedence order.It should be understood that using in this way Data be interchangeable under appropriate circumstances, so as to the embodiment of the present invention described herein can in addition to illustrating herein or Sequence other than those of description is implemented.In addition, term " includes " and " having " and their any deformation, it is intended that cover Cover it is non-exclusive include, for example, the process, method, system, product or equipment for containing a series of steps or units are not necessarily limited to Step or unit those of is clearly listed, but may include be not clearly listed or for these process, methods, product Or other step or units that equipment is intrinsic.

Embodiment 1

An embodiment according to the present invention provides a kind of two-dimensional calibrations method of mapping camera elements of interior orientation, referring to figure 3, comprising the following steps:

The two-dimensional calibrations method of one of embodiment of the present invention mapping camera elements of interior orientation, by adjusting mapping camera Azimuth, pitch angle carry out elements of interior orientation calibration, guarantee that asterism is imaged in the same line battle array of mapping camera, realize To the precision calibration of linear array type mapping camera.The scaling method is simple, and when calibration does not need to parallel light tube, mapping camera, two The mutual alignment relation between turntable is tieed up accurately level.

In as a preferred technical scheme, step e includes:

In as a preferred technical scheme, step c includes:

In as a preferred technical scheme, method includes:

In as a preferred technical scheme, referring to fig. 4, photo coordinate system xNy and turntable coordinate system XOY is defined, as flat X-axis is linear array detector length direction in areal coordinate system, and N is the intersection point in the online array detector of principal point, in turntable coordinate system X-axis with Dimensional turntable pitch axis is parallel, and Y-axis is parallel with dimensional turntable azimuth axis, and mapping camera is mounted in dimensional turntable；M point is two dimension When turntable is located at zero point, picture point of the parallel light tube in linear array detector is typically chosen as the midpoint of linear array detector length direction；

M_O=C_N ^OM_N+T (29)

Then in Rt Δ O₁In SH:

G_N1=(C_N ^O)^-1(G_O1-T) (34)

In as a preferred technical scheme, the elements of interior orientation of mapping camera includes principal point, main away from, distortion.

Embodiment 2

Another embodiment according to the present invention provides a kind of two-dimensional calibrations device of mapping camera elements of interior orientation, referring to Fig. 5, comprising:

First recording unit 201, in the geometric center for being radiated at linear array detector in mapping camera using directional light After position is imaged, the azimuth of mapping camera and pitch angle at this time are recorded；

Second recording unit 202, for change mapping camera azimuth and pitch angle, until directional light re-imaging After in the linear array detector of mapping camera, record is at this time in the azimuth of mapping camera, pitch angle and linear array detector imaging Image point position coordinate；

Acquiring unit 203, the picture in azimuth, pitch angle and linear array detector imaging for recording multiple mapping cameras Point position coordinates；

Computing unit 204, for according to the picture in the imaging of the azimuth of multiple mapping cameras, pitch angle and linear array detector Point position coordinates calculate the elements of interior orientation of mapping camera.

The two-dimensional calibrations device of one of embodiment of the present invention mapping camera elements of interior orientation does not need accurate adjustment and turns The mutual alignment relation of platform, camera and parallel light tube, step is simple, and surveys and draws phase especially suitable for big visual field, big distortion linear array The elements of interior orientation of machine is demarcated, and the caliberating device is as shown in fig. 6, include standard sources 1, light pipe holder 2, parallel light tube 3, mapping Camera 4, dimensional turntable 5, vibration-isolating platform 6 are wherein equipped with the star tester with single asterism hole in 3 image planes of parallel light tube, Demarcating steps are as follows:

A. mapping camera 4 is fixed in dimensional turntable 5；

B. dimensional turntable 5 is adjusted, the directional light of parallel light tube 3 is allowed to be imaged in mapping camera 4 in linear array detector geometry Heart position；Record the azimuth of dimensional turntable 5 and pitch angle at this time；

C. change the azimuth of dimensional turntable 5, whether the asterism for observing star tester can be imaged in linear array detector, such as Fruit can be imaged, and record the azimuth of dimensional turntable 5 and pitch angle at this time, while recording image point position coordinate at this time；If no It can be imaged, adjust the pitching shafting of dimensional turntable 5, change the pitch angle of dimensional turntable 5, until asterism can be imaged on linear array spy It surveys in device, records the azimuth of dimensional turntable 5 and pitch angle at this time, while recording image point position coordinate at this time；

D. step c) is repeated, in the field range of mapping camera 4, azimuth and the pitch angle of dimensional turntable 5 is adjusted, allows Mapping camera 4 is imaged parallel light tube 3 in n angle, records the azimuth and pitch angle of n dimensional turntable 5, records n A image point position coordinate；

E. according to the azimuth of dimensional turntable 5, pitch angle and image point position coordinate, according to the distortion minimum constraint of quadratic sum Condition solves the elements of interior orientation of mapping camera 4.

Beneficial effects of the present invention are at least are as follows:

The present invention carries out elements of interior orientation calibration by adjusting the azimuth of dimensional turntable 5, pitch angle, guarantees asterism imaging In the same line battle array of mapping camera 4, the precision calibration to linear array type mapping camera 4 is realized.

Scaling method is simple, and when calibration does not need to the mutual position between parallel light tube 3, mapping camera 4, dimensional turntable 5 Relationship is set accurately to be leveled.

Below with specific embodiment, caliberating device of the invention is described in detail, the demarcating steps of the caliberating device Are as follows:

A. dimensional turntable 5 is adjusted, the asterism of parallel light tube 3 is allowed to be imaged on linear array detector geometric center position M；

The azimuth of dimensional turntable 5 is set to zero by the pitch angle β for b. recording dimensional turntable 5 at this time；

C. dimensional turntable 5 is rotated, the azimuth and pitch angle, asterism for changing dimensional turntable 5 image in linear array detector G1 Point position, records the azimuth angle alpha of dimensional turntable 5₁And pitch angle (β+d β₁), record G₁Point image point position coordinate G_1x；

D. step c) is repeated, G is successively obtained₂, G₃..., G_nPoint records the pitch angle (β+d β of dimensional turntable 5₂), (β+d β₃) ..., (β+d β_n) and azimuth angle alpha₂, α₃..., α_n, record G₂, G₃..., G_nImage point position coordinate G_2x, G_3x..., G_nx。

E. elements of interior orientation is solved.

Solution procedure is as follows: in order to solve conveniently, photo coordinate system xNy and turntable coordinate system XOY is defined, as plane is sat X-axis is linear array detector length direction in mark system, and N is the intersection point in the online array detector of principal point, X-axis and two dimension in turntable coordinate system 5 pitch axis of turntable is parallel, and Y-axis is parallel with 5 azimuth axis of dimensional turntable.

In order to express conveniently, all the points are expressed in turntable XOY coordinate system, if without specified otherwise in following, All the points are expressed in turntable XOY coordinate system.According to Fig. 4, the conversion of plane coordinate system xNy and turntable coordinate system XOY Relationship are as follows: when M point is that dimensional turntable 5 is located at zero point, picture point of the parallel light tube 3 in linear array detector is typically chosen as linear array spy Survey the midpoint of device length direction；

M_O=C_N ^OM_N+T (36)

Then in Rt Δ O₁In SH:

G_N1=(C_N ^O)^-1(G_O1-T) (41)

Caliberating device of the invention carries out elements of interior orientation calibration by adjusting the azimuth of mapping camera, pitch angle, protects Card asterism is imaged in the same line battle array of mapping camera, realizes the precision calibration to linear array type mapping camera.The calibration side Method is simple, and when calibration does not need accurately to level the mutual alignment relation between parallel light tube, mapping camera, dimensional turntable ?.

The serial number of the above embodiments of the invention is only for description, does not represent the advantages or disadvantages of the embodiments.

In the above embodiment of the invention, it all emphasizes particularly on different fields to the description of each embodiment, does not have in some embodiment The part of detailed description, reference can be made to the related descriptions of other embodiments.

In several embodiments provided herein, it should be understood that disclosed technology contents can pass through others Mode is realized.Wherein, system embodiment described above is only schematical, such as the division of unit, can be one kind Logical function partition, there may be another division manner in actual implementation, such as multiple units or components can combine or can To be integrated into another system, or some features can be ignored or not executed.Another point, shown or discussed is mutual Coupling, direct-coupling or communication connection can be through some interfaces, the indirect coupling or communication connection of unit or module, It can be electrical or other forms.

Unit may or may not be physically separated as illustrated by the separation member, shown as a unit Component may or may not be physical unit, it can and it is in one place, or may be distributed over multiple units On.It can some or all of the units may be selected to achieve the purpose of the solution of this embodiment according to the actual needs.

It, can also be in addition, the functional units in various embodiments of the present invention may be integrated into one processing unit It is that each unit physically exists alone, can also be integrated in one unit with two or more units.Above-mentioned integrated list Member both can take the form of hardware realization, can also realize in the form of software functional units.

It, can if integrated unit is realized in the form of SFU software functional unit and when sold or used as an independent product To be stored in a computer readable storage medium.Based on this understanding, technical solution of the present invention substantially or Say that all or part of the part that contributes to existing technology or the technical solution can embody in the form of software products Out, which is stored in a storage medium, including some instructions are used so that a computer equipment (can be personal computer, server or network equipment etc.) executes all or part of step of each embodiment method of the present invention Suddenly.And storage medium above-mentioned includes: USB flash disk, read-only memory (ROM, Read-Only Memory), random access memory The various media that can store program code such as (RAM, Random Access Memory), mobile hard disk, magnetic or disk.

The above is only a preferred embodiment of the present invention, it is noted that for the ordinary skill people of the art For member, various improvements and modifications may be made without departing from the principle of the present invention, these improvements and modifications are also answered It is considered as protection scope of the present invention.

Claims

1. a two-dimensional calibration method of orientation elements in a surveying and mapping camera, is characterized in that, comprises the following steps:

Step b: use parallel light to illuminate the geometric center position of the linear array detector in the surveying and mapping camera for imaging, and record the azimuth and elevation angles of the surveying and mapping camera at this time;

Step c: Change the azimuth and elevation angles of the surveying and mapping camera until the parallel light is imaged in the linear array detector of the surveying and mapping camera again, and record the azimuth and elevation angles of the surveying and mapping camera and the image point position in the imaging of the linear detector. coordinate;

Step d: Repeat step c for many times to obtain the azimuth angle, the pitch angle of the plurality of surveying and mapping cameras, and the position coordinates of the image points in the imaging of the linear array detector;

Step e: Calculate the inner azimuth element of the surveying and mapping cameras according to the azimuth and pitch angles of the plurality of surveying and mapping cameras and the position coordinates of the image points in the imaging of the linear array detector.

2. The method according to claim 1, wherein the step e comprises:

According to the azimuth and pitch angles of multiple surveying and mapping cameras and the image point position coordinates in the imaging of the linear array detector, and using the minimum sum of distortion squares as the constraint condition, the least squares adjustment method is used to calculate the inner orientation elements of the surveying and mapping cameras. .

3. The method according to claim 1, wherein the step c comprises:

Change the azimuth angle of the surveying and mapping camera to determine whether the parallel light can be imaged in the linear array detector of the surveying and mapping camera, and if so, record the azimuth angle, pitch angle of the surveying and mapping camera and the image point position coordinates in the imaging of the linear array detector; If not, change the pitch angle of the surveying and mapping camera until the parallel light can be imaged in the linear array detector of the surveying and mapping camera, and record the azimuth angle, pitch angle of the surveying and mapping camera and the image point position coordinates in the imaging of the linear array detector.

4. The method of claim 1, wherein the method comprises:

Step b: use parallel light to illuminate the geometric center position of the linear array detector in the surveying and mapping camera for imaging, record the elevation angle β of the surveying and mapping camera at this time, and set the azimuth angle of the surveying and mapping camera to zero;

Step c: Change the azimuth angle and pitch angle of the surveying and mapping camera until the parallel light is imaged again at the position of the line detector _G1 of the surveying and mapping camera, record the azimuth angle α1 and the pitch angle (β ₊ _dβ1 ) of the surveying and mapping camera, and record G ₁ point image point position coordinate G _1x ;

Step d _: Repeat step _c for many _times , obtain G ₂ , G ₃ , . β ₊ dβ _n ) and azimuth angles α ₂ , α ₃ ,...,α _n , record _G ₂ , _G ₃ , _... ;

Step e: Calculate the inner azimuth element of the surveying and mapping cameras according to the azimuth and pitch angles of the n surveying and mapping cameras and the position coordinates of the image points in the imaging of the linear array detector, where n is an integer greater than or equal to 1.

5. The method according to claim 4, wherein the image plane coordinate system xNy and the turntable coordinate system XOY are defined, the x-axis in the image plane coordinate system is the long direction of the linear array detector, and N is the main point of the linear array detector. In the vertical foot of the turntable coordinate system, the X axis is parallel to the pitch axis of the two-dimensional turntable, and the Y axis is parallel to the azimuth axis of the two-dimensional turntable. The image point in the linear array detector;

The transformation relationship between the plane coordinate system xNy and the turntable coordinate system XOY is:

M _O =C _N ^O M _N +T (1)

In formula (1), M _O is the coordinate of point M in the turntable coordinate system XOY, M _N is the coordinate of point M in the plane coordinate system xNy, the x coordinate of the M _O point is M _Ox , the y coordinate is M _Oy , _CN ^O is the 2×2 rotation matrix of the transformation from the plane coordinate system xNy to the turntable coordinate system XOY:

In formula (2), θ represents the angle between the linear array detector and the rotation direction of the two-dimensional turntable, formula (1) y ₀ is the y-direction coordinate of the main point, and the distortion of G ₁ can be solved as follows: when the two-dimensional turntable rotates around its azimuth axis by α ₁ and then rotates around its elevation axis by dβ ₁ , the star point of the parallel light is in the image plane coordinate system xNy The mid-projection point moves from point M to point G ₁ , then in RtΔOO ₁ S, we can obtain:

In formula (3), f is the main distance of the surveying and mapping camera, M _Ox is the x coordinate of the M point in the turntable coordinate system XOY, M _Oy is the y coordinate of the M point in the turntable coordinate system XOY, and SO ₁ is the length of the line segment SO ₁ ; dα is the rotation angle of the two-dimensional turntable in the azimuth direction when the collimator is rotated from point M to point S;

Then in RtΔO ₁ SH:

In formula (4), SH represents the length of the line segment SH, H _Ox is the x coordinate of the point H in the turntable coordinate system XOY, and H _Oy is the y coordinate of the M point in the turntable coordinate system XOY;

After the H point is obtained, the G ₁ point is solved in RtΔOKO ₁ , RtΔG ₁ KO ₁ :

In formula (5), O ₁ K represents the length of line segment O ₁ K, and G _1Ox and G _1Oy are the x and y coordinates of point G ₁ in the turntable coordinate system XOY, respectively. According to formula (1), we can obtain:

G _N1 = (C _N ^O ) ^-1 (G _O1 -T) (6)

In formula (6), (C _N ^O ) ^-1 represents the inverse matrix of the matrix C _N ^O ; G _N1 is the coordinate of the point G ₁ in the plane coordinate system xNy, and its x and y coordinates are respectively recorded as G _N1x and G _N1y , then The distortion of _G1 point can be obtained as:

In formula (7), DG _1x represents the x-direction distortion of the G point, and DG _1y represents the y-direction distortion of the G point; in the whole calibration process, a total of n calibration points G ₁ , G ₂ , G ₃ ,..., G _n are obtained. , then according to The minimum is a constraint condition, and by using the least squares adjustment method, the principal points x ₀ , y ₀ of the surveying and mapping camera, principal distance f, and distortion Δ _i can be obtained.

6 . The method according to claim 1 , wherein the interior orientation elements of the surveying and mapping camera include principal point, principal distance, and distortion. 7 .

7. A two-dimensional calibration device for orientation elements in a surveying and mapping camera, characterized in that, comprising:

The first recording unit is used to record the azimuth angle and the pitch angle of the surveying and mapping camera at this time after using the parallel light to illuminate the geometric center position of the linear array detector in the surveying and mapping camera for imaging;

The second recording unit is used to record the azimuth angle, elevation angle and linear array detector of the surveying and mapping camera at this time after changing the azimuth angle and the elevation angle of the surveying and mapping camera until the parallel light is imaged in the linear array detector of the surveying and mapping camera again. Image point position coordinates in imaging;

an acquisition unit, used for recording the azimuth angle, the pitch angle of the plurality of surveying and mapping cameras and the image point position coordinates in the imaging of the linear array detector;

The calculation unit is used for calculating the inner azimuth element of the surveying and mapping camera according to the azimuth angle, the pitch angle of the plurality of surveying and mapping cameras and the position coordinates of the image point in the imaging of the linear array detector.

8 . The device according to claim 7 , wherein the calculation unit is configured to use the distortion sum of squares according to the azimuth angle, the elevation angle of a plurality of surveying cameras and the position coordinates of the image points in the imaging of the linear array detector. 9 . The minimum is the constraint condition, and the least squares adjustment method is used to calculate the interior orientation elements of the surveying and mapping camera.

9. The device according to claim 7, wherein the calculation step of the calculation unit is:

Define the image plane coordinate system xNy and the turntable coordinate system XOY. In the image plane coordinate system, the x-axis is the long direction of the linear array detector, N is the main point of the vertical foot of the linear array detector, and the X-axis in the turntable coordinate system is related to the two-dimensional turntable. The pitch axis is parallel, the Y axis is parallel to the azimuth axis of the two-dimensional turntable, and the surveying and mapping camera is installed on the two-dimensional turntable; point M is the image point of the collimator in the line array detector when the two-dimensional turntable is at the zero point;

M _O =C _N ^O M _N +T (8)

Then in RtΔO ₁ SH:

G _N1 = (C _N ^O ) ^-1 (G _O1 -T) (13)

10 . The device according to claim 7 , wherein the interior orientation elements of the surveying and mapping camera include principal point, principal distance, and distortion. 11 .