CN106023193B - A kind of array camera observation procedure detected for body structure surface in turbid media - Google Patents
A kind of array camera observation procedure detected for body structure surface in turbid media Download PDFInfo
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Abstract
The invention discloses a kind of array camera observation procedures detected for body structure surface in turbid media, using camera array device, observed range can be greatly shortened in the case that visual field size is constant, imaging definition is improved, to realize the purpose that body structure surface blur-free imaging is carried out in turbid media.This method includes the following steps：Each camera is demarcated using encoded point scaling board, while obtains the spin matrix and translation matrix of the inner parameter matrix of each camera, distortion parameter matrix, camera coordinates system and world coordinate system；Calculate camera array ideal inner parameter matrix；Calculate image homograph matrix；Camera photocentre correction calculates；Lens distortion calibration calculates；The mapping relations of single camera image and array image, that is, look-up table calculates；Body structure surface high resolution imaging shows and detects.
Description
Technical field
It is especially a kind of the present invention relates to a kind of array camera observation procedure detected for body structure surface in turbid media
It is observed using what digital image processing techniques and camera calibration technology were realized for the fine definition body structure surface in turbid media
Method.
Background technology
Structure can be influenced during military service by various conditions, the damage that these influences can cause structure different degrees of
Wound, influences its normal use.Therefore it is extremely important to the safety detection of structure, Surface testing is wherein important
One side.Surface testing refer to the measurement of the geometric dimension to overall structure and partial structurtes, the detection of Structural defect with
Measure etc..
Surface testing generally carries out structure, but be situated between as muddy in some complex conditions using one camera under normal condition
In matter, if observed range farther out when, influenced by optical transmission medium, hardly result in clearly apparent image；But observed range is near
When, visual field can then become smaller.Most of camera arrays are difficult to ensure that using remote imaging, image definition at present, so far
Do not occur a kind of array camera method that can be used for body structure surface detection in turbid media also.
Invention content
Technical problem：The present invention provides a kind of easy to operate, it is easy to accomplish, it can be with real-time display structure in detection process
The array camera observation procedure detected for body structure surface in turbid media of surface image.
Technical solution：The array camera observation procedure detected for body structure surface in turbid media of the present invention, including with
Lower step：
1) array camera is demarcated：Encoded point scaling board is placed in tested structural plan position, all cameras of array, which synchronize, to be adopted
Collect scaling board image, obtain one group of image 0；Scaling board is translated into known distance, array phase along the direction vertical with its plane
Machine synchronous acquisition scaling board image, obtains one group of image 1；Two-step method mark is utilized by each camera the image collected 0 and image 1
Surely all parameters of the camera are obtained, the camera parameter includes：Inner parameter matrix Ai, lens distortion parameter matrix Di, camera
Optical center coordinate system relative to encoded point scaling board world coordinate system spin matrix Ri=[RI, x RI, y RI, z] and translation matrix Ti
=[TI, x TI, y TI, z], the inner parameter matrix isWherein fI, x、fI, yFor i-th camera
Horizontal direction and vertical direction equivalent focal length, i=1,2 ..., m, m be camera number, siFor obliquity factor, cI, x、cI, yFor mirror
The optical axis of head and the pixel coordinate of target surface intersection point；
2) array camera synchronous acquisition body structure surface image calculates the structure table of each camera acquisition according to relationship below
The homograph matrix H of face imagei：
AidealRideal=HiAiRi
3) world coordinates of each camera photocentre is calculated firstWherein Ci=[CI, x CI, y CI, z], then
Calculate correction after optical center to body structure surface distance CIdeal, z, CIdeal, zFor C in all camera photocentre world coordinatesI, zBe averaged
Value；
4) using the upper left corner camera in camera array as camera 1, all camera photocentres are calculated according to the following formula relative to camera 1
The horizontal and vertical pixel translation x of optical centertrans、ytrans：
xtrans=(CI, x-C1, x)×fIdeal, x/CIdeal, z
ytrans=(CI, y-C1, y)×fIdeal, y/CIdeal, z
5) all the points in array image are traversed as follows, calculate the body structure surface figure for determining single camera acquisition
As the mapping relations with array image：For any point on array image, all camera phases obtained according to the step 4)
The pixel of camera 1 is translated, the point is calculated positioned at the picture position of i-th of camera, is then obtained using the step 3)
The distance of optical center to body structure surface carries out optical center position correction to each camera after correction, should using the list that the step 2) obtains
Transformation matrix carries out homograph correction, finally using the lens distortion parameter matrix that the step 1) obtains into line distortion school
Just；
The optical center position correction is carried out according to equation below：
xideal-cIdeal, x=(xi-cIdeal, x)×CI, z/CIdeal, z
yideal-cIdeal, y=(yi-cIdeal, y)×CI, z/CIdeal, z
Wherein xi、yiTo correct the image coordinate at preceding any point, xideal、yidealImage for any point after correction is sat
Mark；
6) pixel value of each picture point in the mapping relations computing array image obtained by the step 5), and thereby
It obtains array image and carries out array image in real time showing and the detection of structure apparent face.
Further, in the method for the present invention, in the step 1), lens distortion parameter matrix is joined including 6 rank radial distortions
Number K1、K2、K3、K4、K5、K6With 2 rank tangential distortion parameter matrix P1、P2。
Further, in the method for the present invention, in the step 2), scaling board image includes but are not limited to encoded point.
The method of the present invention shortens observed range in the case where visual field size is constant, carries by using camera array device
Imaging definition in high turbid media, it is final to realize the purpose that body structure surface detection is carried out in turbid media.
Advantageous effect：Compared with prior art, the present invention it has the following advantages：
(1) it is tested body structure surface visual inspection.Compared with the detection techniques such as other acoustic imagings, the present invention uses optical imagery
Technology can be directly observed body structure surface original image, more intuitively, effectively.
(2) body structure surface imaging is more clear.Traditional one camera body structure surface detection image-forming range farther out, visual field compared with
It is small；And the present invention is not only increased visual field, while shorten observed range, is reduced muddy Jie using array camera device
It verifies in the influence of imaging definition, improves body structure surface imaging definition.
(3) it is simple to operate.The present invention only needs two steps that calibration can be completed, due to using fixed using encoded point
Array camera device, calibration is primary when need to only dispatch from the factory, and carries out to demarcate again during body structure surface detection later.
(4) body structure surface detects in real time.The present invention, can direct computing array image by way of building look-up table
Pixel value, and suitable for multithreading concurrent operation；Compared to the method computational efficiency higher using image mosaic.
Description of the drawings
Fig. 1 is encoded point scaling board, is the standard component of known dimensions.
Fig. 2 is inventive method flow chart.
Specific embodiment
With reference to embodiment and Figure of description, the present invention is further illustrated.
Prepare a camera array device：Camera is ordered in by grid arrangement mode on rigid mount, wherein all cameras
The cameras such as image resolution ratio, aperture, focal length it is consistent with lens parameters, the visual field size of single camera is about 8cm × 6cm,
Observed range is about 11cm, and horizontal distance is slightly less than the width of single camera visual field between adjacent cameras, and vertical distance is slightly less than list
The height of a viewing field of camera, keeping parallelism as possible between camera and camera；This arrangement mode can both make full use of the figure of camera
As resolution ratio can ensure that between adjacent cameras there is certain overlapping region again, so as to ensure the continuity of final array image.If
Underwater condition carries out body structure surface detection, then camera should have water-tight device, for ensure under low light condition can blur-free imaging,
4 LED light should be at least arranged to improve brightness around each camera.
The array camera observation procedure detected for body structure surface in turbid media includes the following steps：
1) array camera is demarcated：Encoded point scaling board shown in Fig. 1 is placed in tested structural plan position, uses mobile working
All camera synchronous acquisition scaling board images of stand control array, obtain one group of image 0；By scaling board along vertical with its plane
Direction translates known distance, and array camera synchronous acquisition scaling board image obtains one group of image 1；It is collected by each camera
Image 0 and image 1 are demarcated to obtain all parameters of the camera using two-step method；This method only needs two steps can calibration for cameras
Multiple measurement can be realized without calibration again after primary calibration terminates in all parameters.Using encoded point scaling board conduct
Demarcate pattern, which is characterized in that each characteristic point can with unique identification, in calibration process the image coordinate of each characteristic point and
World coordinates can uniquely determine, and scaling board herein includes but are not limited to encoded point scaling board.The camera parameter includes：
Inner parameter matrix Ai, lens distortion parameter matrix Di, camera photocentre coordinate system is relative to encoded point scaling board world coordinate system
Spin matrix Ri=[RI, x RI, y RI, z] and translation matrix Ti=[TI, x TI, y TI, z].Inner parameter matrixWherein fI, x、fI, yFor the horizontal direction and vertical direction equivalent focal length of i-th of camera, i=1,
2nd ..., m (m is camera number), siFor obliquity factor, cI, x、cI, yThe pixel coordinate of optical axis and target surface intersection point for camera lens；Mirror
Head distortion parameter matrix generally comprises 6 rank radial distortion parameter K1、K2、K3、K4、K5、K6With 2 rank tangential distortion parameter matrix P1、
P2, lens distortion parameter matrix be mainly used to correction due to lens distortion and caused by image fault.
2) array camera synchronous acquisition body structure surface image calculates the structure table of each camera acquisition according to relationship below
The homograph matrix H of face imagei：
AidealRideal=HiAiRi
3) due to the installation error of camera, the optical center of all cameras can not possibly be in the same plane, thus needs to carry out
Camera photocentre position correction.The world coordinates of each camera photocentre is calculated firstWherein Ci=[CI, x CI, y
CI, z].Then the distance for calculating optical center to body structure surface after correcting is CIdeal, z, CIdeal, zFor in all camera photocentre world coordinates
CI, zAverage value.
4) using the upper left corner camera in camera array as camera 1, all camera photocentres are calculated according to the following formula relative to camera 1
The horizontal and vertical pixel translation x of optical centertrans、ytrans：
xtrans=(CI, x-C1, x)×fIdeal, x/CIdeal, z
ytrans=(CI, y-C1, y)×fIdeal, y/CIdeal, z
5) all the points in array image are traversed as follows, calculate the body structure surface figure for determining single camera acquisition
As the mapping relations with array image：For any point on array image, all camera phases obtained according to the step 4)
The pixel of camera 1 is translated, the point is calculated positioned at the picture position of i-th of camera, is then utilized respectively the step 3) and obtains
To correction after the distance of optical center to structural plan carry out optical center position correction to each camera, obtained using the step 2)
Homograph matrix carries out homograph correction, finally using the lens distortion parameter matrix that the step 1) obtains into line distortion
Correction.The all the points in array image are traversed, mapping relations, that is, look-up table, which calculates, to be completed.
The optical center position correction is carried out according to equation below：
xideal-cIdeal, x=(xi-cIdeal, x)×CI, z/CIdeal, z
yideal-cIdeal, y=(yi-cIdeal, y)×CI, z/CIdeal, z
Wherein xi、yiTo correct the image coordinate at preceding any point, xideal、yidealImage for any point after correction is sat
Mark.
6) pixel value of each picture point in the quick computing array image of mapping relations obtained by the step 5), from
And obtain array image.Calibration once obtains the mapping relations of the step 5) when array camera device need to only dispatch from the factory, later
The mapping relations can be directly utilized in detection process, body structure surface array can be calculated and be shown using multithreading in real time
Image.
Above-described embodiment is only the preferred embodiment of the present invention, it should be pointed out that：For the ordinary skill of the art
For personnel, without departing from the principle of the present invention, several improvement and equivalent replacement can also be made, these are to the present invention
Claim be improved with the technical solution after equivalent replacement, each fall within protection scope of the present invention.
Claims (3)
1. a kind of array camera observation procedure detected for body structure surface in turbid media, which is characterized in that this method includes
Following steps：
1) array camera is demarcated：Encoded point scaling board is placed in tested structural plan position, all camera synchronous acquisition marks of array
Fixed board image obtains one group of image 0；Scaling board is translated into known distance along the direction vertical with its plane, array camera is same
Step acquisition scaling board image, obtains one group of image 1；It is demarcated by each camera the image collected 0 and image 1 using two-step method
To all parameters of the camera, the camera parameter includes：Inner parameter matrix Ai, lens distortion parameter matrix Di, camera photocentre
Coordinate system relative to encoded point scaling board world coordinate system spin matrix Ri=[RI, x RI, y RI, z] and translation matrix Ti=
[TI, x TI, y TI, z], the inner parameter matrix isWherein fI, x、fI, yWater for i-th of camera
Square to vertical direction equivalent focal length, i=1,2 ..., m, m be camera number, siFor obliquity factor, cI, x、cI, yFor camera lens
Optical axis and target surface intersection point pixel coordinate；
2) array camera synchronous acquisition body structure surface image calculates the body structure surface figure of each camera acquisition according to relationship below
The homograph matrix H of picturei：
Wherein fIdeal, x、fIdeal, y、sidealFor all camera fI, x、fI, y、siAverage value, cIdeal, xAnd cIdeal, yFor each camera
Image list should correct after imaging region maximum preferable principal point coordinate, RidealFor unit matrix,
3) world coordinates of each camera photocentre is calculated firstWherein Ci=[CI, x CI, y CI, z], then calculate
Optical center is to the distance C of body structure surface after correctionIdeal, z, CIdeal, zFor C in all camera photocentre world coordinatesI, zAverage value；
4) using the upper left corner camera in camera array as camera 1, all camera photocentres are calculated according to the following formula relative to 1 optical center of camera
Horizontal and vertical pixel translation xtrans、ytrans：
xtrans=(CI, x-C1, x)×fIdeal, x/CIdeal, z
ytrans=(CI, y-C1, y)×fIdeal, y/CIdeal, z
5) as follows traverse array image in all the points, calculate determine single camera acquisition body structure surface image with
The mapping relations of array image：For any point on array image, according to all cameras that the step 4) obtains relative to
The pixel translation of camera 1, calculates the point positioned at the picture position of i-th of camera, the correction then obtained using the step 3)
The distance of optical center to body structure surface carries out optical center position correction, the homograph obtained using the step 2) to each camera afterwards
Matrix carries out homograph correction, finally carries out distortion correction using the lens distortion parameter matrix that the step 1) obtains；
The optical center position correction is carried out according to equation below：
xideal-cIdeal, x=(xi-cIdeal, x)×CI, z/CIdeal, z
yideal-cIdeal, y=(yi-cIdeal, y)×CI, z/CIdeal, z
Wherein xi、yiTo correct the image coordinate at preceding any point, xideal、yidealImage coordinate for any point after correction；
6) pixel value of each picture point in the mapping relations computing array image obtained by the step 5), so as to obtain battle array
Row image.
2. the array camera observation procedure according to claim 1 detected for body structure surface in turbid media, feature
It is, in the step 1), lens distortion parameter matrix includes 6 rank radial distortion parameter K1、K2、K3、K4、K5、K6It is tangential with 2 ranks
Distortion parameter matrix P1、P2。
3. the array camera observation procedure according to claim 1 or 2 detected for body structure surface in turbid media, special
Sign is, in the step 1), scaling board image includes but are not limited to encoded point.
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| CN107643213B (en) * | 2017-07-31 | 2018-07-20 | 东南大学 | A kind of high temperature strain measurement method for eliminating off face Influence of Displacement |
| CN107687821B (en) * | 2017-08-24 | 2019-11-15 | 南京理工大学 | Polyphaser light knife system scaling method for deep holes revolving part topography measurement |
| CN108154534B (en) * | 2017-12-26 | 2020-09-01 | 努比亚技术有限公司 | Picture definition calibration method, terminal and computer readable storage medium |
| CN110298878B (en) * | 2018-03-21 | 2021-03-12 | 北京猎户星空科技有限公司 | Method and device for determining three-dimensional pose of target object and electronic equipment |
| CN110530869B (en) * | 2018-05-25 | 2022-08-23 | 上海翌视信息技术有限公司 | Detection system based on position information and image information |
| CN109099883A (en) * | 2018-06-15 | 2018-12-28 | 哈尔滨工业大学 | The big visual field machine vision metrology of high-precision and caliberating device and method |
| CN112435303B (en) * | 2020-12-09 | 2024-03-19 | 华中科技大学 | Method and system for constructing correction table of galvanometer system and method for correcting galvanometer system |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104182969A (en) * | 2014-08-08 | 2014-12-03 | 河南科技大学 | Internal and external parameter calibration method of single-scanline camera |
| CN104635278A (en) * | 2014-12-18 | 2015-05-20 | 中国海洋大学 | Detection device and detection method for target image of large non-uniform light field |
| CN105303574A (en) * | 2015-07-30 | 2016-02-03 | 四川大学 | Integrated imaging camera array calibration method based on homography transformation |
| US9310191B1 (en) * | 2008-07-08 | 2016-04-12 | Bae Systems Information And Electronic Systems Integration Inc. | Non-adjustable pointer-tracker gimbal used for directed infrared countermeasures systems |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US9392189B2 (en) * | 2014-02-28 | 2016-07-12 | Intel Corporation | Mechanism for facilitating fast and efficient calculations for hybrid camera arrays |
-
2016
- 2016-05-18 CN CN201610328899.9A patent/CN106023193B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US9310191B1 (en) * | 2008-07-08 | 2016-04-12 | Bae Systems Information And Electronic Systems Integration Inc. | Non-adjustable pointer-tracker gimbal used for directed infrared countermeasures systems |
| CN104182969A (en) * | 2014-08-08 | 2014-12-03 | 河南科技大学 | Internal and external parameter calibration method of single-scanline camera |
| CN104635278A (en) * | 2014-12-18 | 2015-05-20 | 中国海洋大学 | Detection device and detection method for target image of large non-uniform light field |
| CN105303574A (en) * | 2015-07-30 | 2016-02-03 | 四川大学 | Integrated imaging camera array calibration method based on homography transformation |
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