CN110533618A - A kind of method and photographic means of lens distortion correction - Google Patents
A kind of method and photographic means of lens distortion correction Download PDFInfo
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Abstract
The method and photographic means of lens distortion correction of the present invention belong to video imaging field, including correction parameter module, control module, lens module, sensor devices, image flame detection module, display module and memory module；For the combination of different camera lenses and sensor devices, measurement obtains corresponding parameter value, is quickly corrected by the radial distortion that sensor devices can be taken image by retrospectively calculate；The camera arrangement uses the antidote, for close-up and sensor devices, creates the correction argument sequence under different focal length, and when taking pictures, the correction found a view and shot in real time is calculated；The method have the characteristics that simple and quick, the method can be realized under the conditions of multiple hardwares, and the device is used for commercial measurement, and video detection etc. can promote picture fidelity in application, measurement accuracy can be effectively improved when for taking pictures, and restore real scene.
Description
Technical field
The invention belongs to video imaging fields, are related specifically to the method and photographic means of a kind of lens distortion correction.
Background technique
In all video imaging systems, be all made of camera lens and sensor devices, usual camera lens due to optical characteristics limit,
It always has distortion to generate, although by using non-spherical lens, the mode of a variety of lens combinations can maximally reduce mirror
The distortion of head itself, but current technology means, still can not produce the camera lens absolutely not to distort, particularly with varifocal
Away from camera lens, basically can not meet simultaneously all has lesser distortion in long-focus and short focus.
When using film as sensor devices, the distortion of video imaging will depend on camera lens, when using sense electronics
When optical device, video signal is directly translated as digitized electric signal, may further be carried out by computer technology
Reason, corrects the distortion of camera lens, to obtain more true video image.
The distortion that camera lens generates mainly is made of radial distortion and tangential distortion, and wherein tangential distortion is mainly due to camera lens
Optical axis and sensor devices out of plumb and cause, under the conditions of modern processing technique, tangential distortion can be ignored substantially, therefore of the invention
The method and photographic means are corrected for the radial distortion of camera lens.
The radial distortion of camera lens can be divided into barrel distortion and pincushion distortion, both distortion Producing reasons, be all with
The intersection point of camera lens optical axis and imaging plane be origin, and perpendicular to the plane of optical axis be coordinate plane polar coordinate system in, camera lens
Actual imaging on sensor devices and ideal distortionless imaging, radially non-linear relationship, for barrel-shaped abnormal
Become, from the farther pixel of origin, actual imaging point is closer apart from origin than ideal distortionless imaging point；For pincushion distortion
Then on the contrary, from the farther pixel of origin, actual imaging point is farther apart from origin than ideal distortionless imaging point；It is retouched with mathematics
Stating can be expressed as:
rd=f (r) (1)
Wherein rdFor actual imaging point pixel coordinate to the distance of origin, r is ideal undistorted imaging point pixel coordinate to former
The distance of point.
Under normal conditions, the function f in (1) formula is not simple function, for fish eye lens etc., with big shooting angle
Camera lens, f cannot even be expressed using analytical function, and for zoom lens, f is also not unalterable, such as some
Zoom lens distort in long-focus as pincushion distortion, and distortion is barrel distortion in short focus；But for generally answering
With scene, such as common photographing camera, industrial camera, optical measurement video camera, camera lens radial distortion itself and flake mirror
Head ratio, relatively small, f can use simple function approximate description, or be described using the combination of simple function.
Summary of the invention
Present invention seek to address that the above problem can be by using letter for the lesser usage scenario of camera lens radial distortion
Single function describes the non-linear relation of radial distortion.
The method of lens distortion of the present invention correction, according to the feature of camera lens radial distortion, with camera lens optical axis at
As plane intersection point be origin, and perpendicular to the plane of optical axis be coordinate plane polar coordinate system in, by the radial distortion of camera lens
Expression are as follows:
rd=K (r) r
Wherein rdFor actual imaging point pixel coordinate to origin distance；R is ideal undistorted imaging point pixel coordinate to original
The distance of point；K (r) is a function close to constant 1, and when r → 0, K → 1, when barrel distortion, for K with r monotone decreasing, pincushion is abnormal
When change, K is with r monotonic increase；
In the method, exponential function (the i.e. e with natural constant e the bottom of for is selectedxFunction) carry out approximate substitution K function, this be because
Are as follows: exFunction is in physics, most of decaying, conductive process trend function, meet general physics law；exFunction is symbol
Close the simplest Nonlinear Monotone function of K Function feature；Use exAs the approximate function of K function, can be expressed with one
Formula describes barrel distortion and pincushion distortion and zero distortion simultaneously；CPU and GPU with math co-processor contain ex
The quick computations of function, it can be achieved that computer quick calculating；In the lesser situation of lens distortion itself, K function is pressed
When according to Taylor series expansion, constant 1 occupies leading position, other high-order terms account for specific gravity is smaller, the e of this trend and x → 0x
Characteristic it is very close；Use exWhen approximate expression K function, combination for fixed focus lens and specific sensor devices can
Entire distortion degree is described using single parameter, the combination for zoom lens and specific sensor devices, when focal length determines,
The distortion degree under corresponding focal length is described with specific parameter, the distortion parameter of entire zoom lens can be described as
One using lens focus as the function of independent variable.
For pincushion distortion, the pixel of any non-origin, actual imaging point is wanted than ideal distortionless imaging point from origin
Far, and this separate degree increases with the distance of pixel to origin and is increased, with exWhen approximate K function, it can be expressed as:
rd=ea·r·r …a≥0 (3)
Opposite, for barrel distortion, the pixel of any non-origin, actual imaging point is than ideal distortionless imaging point, distance
Origin is close, and this close degree that contracts increases with the distance of pixel to origin and increased；With exWhen approximate K function, it can express
Are as follows:
It further, can be with the expression of Unified Form by barrel distortion and pincushion distortion are as follows:
rd=ea·rR ... a is real number (5)
As a<0, barrel distortion is represented, as a>0, represents pincushion distortion, as a=0, ea·r≡ 1, substantially represents
There is no a radial distortion, i.e., zero distortion, | a | it is more serious more greatly to represent distortion；
Combination for the camera lens and sensor devices of fixed focal length, when camera lens and sensor devices parameter and characteristic determine, a mono-
A constant；
Combination for zoom lens and sensor devices, when camera lens and sensor devices parameter and characteristic determine, a is variable
The function of focal length lens focal length F, and the function is continuous monotonic function；
For having the shooting image of radial distortion, a is obtained by mensuration, according to above formula, retrospectively calculate is carried out, can be obtained
Distort smaller correcting image；
For the pixel coordinate (x, y) of ideal orthoscopic image, corresponding actual photographed pixel coordinate (xd,yd) can be with
It is asked by bringing (5) formula into:
Wherein coordinate (x0,y0) it is coordinate of the polar coordinate system origin in actual photographed image rectangular coordinate system, it is usually practical to clap
The centre coordinate of photo is taken the photograph, with actual photographed photo coordinate (xd,yd) pixel color value filling correction after image coordinate (x, y) as
Element further calculates all possible pixel coordinate of image (x, y) to get the correction color value for arriving coordinate (x, y) pixel one by one
Image after being corrected, i.e. completion lens distortion correction.
The method of lens distortion of the present invention correction, described for fixed focus lens, a can be in above-mentioned formula (6)
The detailed process obtained using mensuration are as follows: use the planar graph being made of several vertical bars and horizontal line as being clapped
Object is taken the photograph, the front of measured camera lens and sensor devices combination is placed in and subject plane and camera lens optical axis is vertical, In
In distortionless ideal image, the imaging of all horizontal lines and vertical bar is necessarily straight line, when camera lens has barrel distortion,
The horizontal line and vertical bar of actual photographed image are restrained to picture centre, when camera lens has pincushion distortion, actual photographed figure
The horizontal line and vertical bar of picture are dissipated to image peripheral；
An arbitrary a value is selected, (6) formula of use carries out correction calculating to the image that actually photographed, the figure after being corrected
Picture, using computer graphical processing tool, such as Photoshop, to the horizontal line and vertical line in image after all corrections
Item carries out collimation comparison, adjusts a value according to the distortion characteristics of image after correction, when the image after correction is barrel distortion, subtracts
Small a value increases a value when the image after correction is pincushion distortion, after adjusting a value, reuses (6) formula and carries out correction calculating, weight
Multiple above step, the smallest a value of pattern distortion degree after finding out correction.
The method of lens distortion of the present invention correction, described for zoom lens, a can be in above-mentioned formula (6)
The detailed process obtained by the way of multi-point sampling are as follows: corresponding to its focal length of multiple focometries of zoom lens respectively
A value, formed a value argument sequence；In actual use, according to the real focal length of zoom lens, mathematical interpolation is used
Method calculates the mathematical approximation with a corresponding to real focal length, and the mathematical approximation for further using a of calculating substitutes into (6)
Formula carries out correction calculating to the image of shooting.
The method of lens distortion correction of the present invention, the actual photographed photo coordinate (xd,yd) pixel color value use
Mathematical image interpolation algorithm, which calculates, to be obtained；Described image interpolation algorithm include arest neighbors interpolation algorithm or bilinear interpolation algorithm or
Cubic interpolation algorithm.Radial distortion expression formula (5), (6) are continuous function expression formula, and the image of shooting is digitlization dispersion number
According to the coordinate (x being calculated by above formulad,yd) can not be in most cases aligned with the pixel coordinate of actual photographed, because
Actual photographed photo coordinate (x on thisd,yd) pixel color value need using mathematical interpolation method calculate obtain.
The photographic means of lens distortion of the present invention correction, including correction parameter module, control module, lens module,
Sensor devices, image flame detection module, display module and memory module；The correction parameter module, control module, lens module,
Sensor devices and image flame detection module are sequentially connected electrically；The control module, image flame detection module and display module are successively electrically connected
It connects；The control module, display module and memory module are sequentially connected electrically；The control module is electrically connected with memory module；
The correction parameter module is used to measure and create the correction parameter of camera lens and photoreceptor combination；For zoom lens, rectify
The instruction that positive parameter module is sent according to control module, calculates the correction parameter a under currently used focus condition；The control
Module controls the work of other module cooperatives for receiving user instructions；The lens module is the optical device for imaging,
And the instruction for receiving control module carries out Focussing operation；The sensor devices are digitized for being converted to optical imagery
Electric signal；Described image rectification module is used for the instruction sent according to control module, a value provided using correction parameter module,
Correction in real time is carried out to the image of current sensor devices shooting to calculate；The display module is for carrying out image flame detection module
Correction calculate after image information, in real-time display to display screen；The memory module is used for the instruction according to control module, into
Perhaps shooting vision operation will be in image information or video information storage to corresponding storage media for row photograph.
The method and photographic means of lens distortion correction of the present invention are directed to the combination of different camera lenses and sensor devices, survey
Corresponding parameter value is measured, is quickly corrected by the radial distortion that sensor devices can be taken image by retrospectively calculate；It is described
Camera arrangement use the antidote, for close-up and sensor devices, create the correction under different focal length
Argument sequence, when taking pictures, the correction found a view and shot in real time is calculated；The method have the characteristics that it is simple and quick, it is described
Method can realize that the device is used for commercial measurement, and video detection etc. is in application, can effectively improve under the conditions of multiple hardwares
Measurement accuracy can promote picture fidelity when for taking pictures, restore real scene.
Detailed description of the invention
Fig. 1 is principle schematic diagram of the present invention；
Fig. 2 is zoom lens a of the present invention and F relation schematic diagram.
Fig. 3 is a kind of method implementation flow chart of the lens distortion of the embodiment of the present invention 1 correction；
Fig. 4 is a kind of photographic means structure chart of the lens distortion of the embodiment of the present invention 2 correction；
Fig. 5 is the measurement grid base map of industrial camera shooting；
Fig. 6 is the effect picture after being corrected to measurement with grid base map using method of the invention.
Specific embodiment
With reference to the attached drawing in the embodiment of the present invention, technical solution in the embodiment of the present invention is further retouched
It states, it is clear that described embodiment is only section Example of the invention.Based on the embodiments of the present invention, in this field
Those of ordinary skill's all other embodiment obtained without making creative work, belong to the present invention
The range of protection.
Embodiment one
The method of lens distortion correction of the present invention, according to the feature of camera lens radial distortion, flat with camera lens optical axis and imaging
The intersection point in face is origin, and perpendicular to the plane of optical axis be coordinate plane polar coordinate system in, the radial distortion of camera lens is expressed
Are as follows:
rd=K (r) r
Wherein rdFor actual imaging point pixel coordinate to origin distance；R is ideal undistorted imaging point pixel coordinate to original
The distance of point；K (r) is a function close to constant 1, and when r → 0, K → 1, when barrel distortion, for K with r monotone decreasing, pincushion is abnormal
When change, K is with r monotonic increase；
As shown in Figure 1, for pincushion distortion, the pixel of any non-origin, actual imaging point imaging point more distortionless than ideal, from
Origin is remote, and this separate degree increases with the distance of pixel to origin and increased, with exWhen approximate K function, it can be expressed as:
rd=ea·r·r …a≥0 (3)
Opposite, for barrel distortion, the pixel of any non-origin, actual imaging point is than ideal distortionless imaging point, distance
Origin is close, and this close degree that contracts increases with the distance of pixel to origin and increased；With exWhen approximate K function, it can express
Are as follows:
It further, can be with the expression of Unified Form by barrel distortion and pincushion distortion are as follows:
rd=ea·rR ... a is real number (5)
As a<0, barrel distortion is represented, as a>0, represents pincushion distortion, as a=0, ea·r≡ 1, substantially represents
There is no a radial distortion, i.e., zero distortion, | a | it is more serious more greatly to represent distortion；
Combination for the camera lens and sensor devices of fixed focal length, a are a constant；
Combination for zoom lens and sensor devices, a is the function of zoom lens focal length F, and the function is to connect
Continuous monotonic function；
For having the shooting image of radial distortion, a is obtained by mensuration, according to above formula, retrospectively calculate is carried out, can be obtained
Distort smaller correcting image；
For the pixel coordinate (x, y) of ideal orthoscopic image, corresponding actual photographed pixel coordinate (xd,yd) can be with
It is asked by bringing (5) formula into:
The specific steps of the method for lens distortion correction, as shown in Figure 3:
Step 1: use the grid figure being made of several horizontal linear sections and vertical line section as subject, and will
The center of the optical axis perpendicular alignmnet grid figure of the camera lens of filming apparatus.
In distortionless ideal image, the imaging of all horizontal lines and vertical bar is necessarily straight line, when camera lens is deposited
In barrel distortion, the horizontal line and vertical bar of actual photographed image are restrained to picture centre, when that there are pincushions is abnormal for camera lens
When change, the horizontal line and vertical bar of actual photographed image are dissipated to image peripheral.
Step 2: zoom lens are transferred to the smallest focal length, the distance of mobile subject to camera lens makes entire
Grid figure is then not necessarily to adjust focal length full of entire shooting visual field for the camera lens of fixed focal length.
The combination of specific for one camera lens and sensor devices, a is a constant, for zoom lens and specific
Sensor devices combination, a be zoom lens focal length F function, therefore for zoom lens need from it is multiple not
A is measured on same focal length respectively, and constitutes the sequence of an a parameter, in actual use, according to the practical coke of zoom lens
Away from calculating approximate a value corresponding to real focal length using the method for mathematical interpolation, further use the approximate a being calculated
Value carries out correction calculating to the image of actual photographed.
Step 3: shooting image carries out correction calculating according to (6) formula, the image after being corrected using any a value.
In fact, any a value is theoretically not do any restrictions to a, rule of thumb, the lesser camera lens of radial distortion leads to
Often | a | it is much smaller than 1, can be since | a | it is calculated=0.01, when actual photographed image is barrel distortion, a takes negative, works as reality
When shooting image is pincushion distortion, a takes positive number.
Step 4: according to the distortion performance of image after correction, adjusting a value, from the new image calculated after correcting, until obtaining
The optimal a value of rectification effect, a value of a value or fixed lens under focal length is corresponded to as camera lens；
According to the correcting image that step 3 calculates, the distortion situation of correction readjusts a value, and the image after correction is that pincushion is abnormal
When change, increase a value, when the image after correction is barrel distortion, reduces a value, after adjusting a value, reuse (6) formula and corrected
It calculates, repeats above step, the smallest a value of pattern distortion degree after finding out correction.
Step 5: for zoom lens, adjusting camera lens real focal length, repeats shooting and is calculated according to (6) corresponding burnt
Away from a value.
Step 6: it repeats to adjust the focal length of zoom lens, and takes pictures and calculate a value of corresponding focal length, until adjustment
The focal length of zoom lens is longest focal length.
The a of zoom lens is one using zoom lens focal length as the function of independent variable, thus on need multiple spot
Sampling repeatedly measures the corresponding a value of the focal length, and form an a argument sequence, usual situation under conditions of different focal length
Under, a zoom lens at least sample 5~10 different focal lengths, calculate its corresponding a value.
Step 7: for fixed lens, recording parameter of a value as the progress image flame detection calculating of (6) formula of use, for can
Zoom lens records corresponding a value under multiple focal lengths, as zoom lens use (6) formula carry out correction calculating ginseng
Number Sequence.
By above seven steps perhaps wherein a argument sequence of the available zoom lens of several steps or
The a value of fixed lens；Fixed focus lens rectify the image of actual photographed by the calculating of (6) formula using its a value
Just, focal length zoom lens then used according to real lens, by being obtained after carrying out mathematical interpolation to a argument sequence
The approximate a value of focal length is actually used, the calculating of (6) formula is further used, the image of actual photographed is corrected.
Fig. 2 is the relation schematic diagram between a of zoom lens and focal length F, and usual zoom lens are in short focus
When generate barrel distortion, be to generate pincushion distortion in long-focus, curve is as shown in Fig. 2, a is negative when short focus at this time, long-focus a
It is positive, this camera lens certainly exists a focal length, a zero, i.e. zero distortion point, if the short focus and length of zoom lens
Pincushion distortion is all generated in the case of focal length, then the curve in Fig. 2 is entirely located in above F axis, otherwise the feelings of short focus and long-focus
Barrel distortion is all generated under condition, then the curve in Fig. 2 is then entirely located in below F axis.
Fig. 5 is for optical measurement background grid figure, using industrial camera in actual condition, the figure of shooting
Picture, it is evident that the grid on its boundary not instead of straight line, toe-in, there is barrel distortions for camera lens.
Fig. 6 is the method by Fig. 5 according to embodiment one, the image after being corrected, the grid line after correction in image
The boundary of item and chart board all measures the accuracy with higher resolution ratio relative to original image close to straight line.
Embodiment two
A kind of photographic means of lens distortion correction is respectively as shown in figure 4, by nine module compositions: correction parameter module, control
Molding block, lens module, sensor devices, image flame detection module, display module, memory module.
Wherein control module is the control core of photographic means, completes to receive user instructions, and is controlled according to user instruction whole
A other module cooperatings.
Correction parameter module preserve according to embodiment one measurement obtain camera lens and photoreceptor combination correction parameter a or
Person's a argument sequence is corrected the instruction that parameter module can be sent according to control module, is obtained if camera lens is zoom lens
It takes the actual focal length of current lens, and utilizes a argument sequence, using mathematical interpolation method, calculate a under the conditions of current focus
Approximation.
Lens module is in photographic means, and specific optical device is made of, Ke Yijie camera lens and corresponding control mechanism
By the instruction that control module is sent, the adjusting of the parameters such as lens focus is carried out, it is corresponding to be saved in correction parameter module
There is correction parameter a or a argument sequence with shots match.
Sensor devices are the devices that optical signal is converted into digital signal, specific sensor devices and specific
Camera lens combination will determine specific correction parameter a or a argument sequence, no matter replace sensor devices or camera lens, require
Again according to the method for embodiment one, a a argument sequence is re-measured；For specific equipment, such as specific model
Smart phone, tablet computer etc., camera lens and sensor devices be all it is determining and known, a a argument sequence can be by setting
Standby manufacturer provides or in such a way that internet is shared, obtains and is stored in correction parameter module from other sources.
Image flame detection module is the instruction sent according to control module, a value provided using correction parameter module, to current
The image of sensor devices shooting carries out correction in real time and calculates, image after being corrected in real time, for smart phone, plate electricity
Brain, laptop etc., the CPU or GPU that system itself can be used are calculated.
Display module is that image flame detection module is carried out to the image information after correction calculating, real-time display to display screen, is supplied
User finds a view and shoots reference.
Memory module is the instruction according to control module, taken a picture perhaps shoot vision operation by image information or
In video information storage to corresponding storage media.
Above nine module compositions, one complete photographic means, and real-time distortion correction and video bat may be implemented
It takes the photograph, when being applied to other scenes, image flame detection module can also export the image information after correction to be set to others processing
It is standby, such as the video target seeker of automatic aircraft, the video processing module of industrial detection and the image processing module of optical measurement
Deng.
Claims (5)
1. a kind of method of lens distortion correction, it is characterised in that: according to the feature of camera lens radial distortion, with camera lens optical axis with
The intersection point of imaging plane be origin, and perpendicular to the plane of optical axis be coordinate plane polar coordinate system in, the radial direction of camera lens is abnormal
Become expression are as follows:
rd=K (r) r
Wherein rdFor actual imaging point pixel coordinate to origin distance；R is ideal undistorted imaging point pixel coordinate to origin
Distance；K (r) is a function close to constant 1, and when r → 0, K → 1, when barrel distortion, K is with r monotone decreasing, pincushion distortion
When, K is with r monotonic increase；
Use exFunction substitutes K function, and the radial distortion of further camera lens can be expressed as:
rd=ea·rR ... a is real number (5)
As a<0, barrel distortion is represented, as a>0, represents pincushion distortion, as a=0, ea·r≡ 1, substantially represents
There is no a radial distortion, i.e., zero distortion, | a | it is more serious more greatly to represent distortion；
Combination for the camera lens and sensor devices of fixed focal length, when camera lens and sensor devices parameter and characteristic determine, a mono-
A constant；
Combination for zoom lens and sensor devices, when camera lens and sensor devices parameter and characteristic determine, a is variable
The function of focal length lens focal length F, and the function is continuous monotonic function；
For having the shooting image of radial distortion, a is obtained by mensuration, according to above formula, retrospectively calculate is carried out, can be obtained
Distort smaller correcting image；
For the pixel coordinate (x, y) of ideal orthoscopic image, corresponding actual photographed pixel coordinate (xd,yd) can be with
It is asked by bringing (5) formula into:
Wherein coordinate (x0,y0) it is polar coordinate system origin in the coordinate of actual photographed image rectangular coordinate system, usually actual photographed
The centre coordinate of photo, with actual photographed photo coordinate (xd,yd) pixel color value filling correction after image coordinate (x, y) pixel,
The correction color value for obtaining coordinate (x, y) pixel, is further calculated all possible pixel coordinate of image (x, y) one by one
Image after correction, i.e. completion lens distortion correction.
2. the method for lens distortion correction according to claim 1, it is characterised in that: it is described for fixed focus lens, on
State the detailed process that a can be obtained using mensuration in formula (6) are as follows: use what is be made of several vertical bars and horizontal line
Planar graph as subject, be placed in the front of measured camera lens and sensor devices combination and subject plane and
Camera lens optical axis is vertical, and in distortionless ideal image, the imaging of all horizontal lines and vertical bar is necessarily straight line, works as mirror
When head has barrel distortion, the horizontal line and vertical bar of actual photographed image are restrained to picture centre, when camera lens has pincushion abnormal
When change, the horizontal line and vertical bar of actual photographed image are dissipated to image peripheral；
An arbitrary a value is selected, (6) formula of use carries out correction calculating to the image that actually photographed, the figure after being corrected
Picture, in the image after all corrections horizontal line and vertical bar carry out collimation comparison, according to after correction image it is abnormal
Become Character adjustment a value, when the image after correction is barrel distortion, reduce a value, when the image after correction is pincushion distortion, increases a
Value after adjusting a value, reuses (6) formula and carries out correction calculating, repeat above step, the pattern distortion journey after finding out correction
Spend the smallest a value.
3. the method for lens distortion correction according to claim 1, it is characterised in that: it is described for zoom lens, on
State the detailed process that a can be obtained by the way of multi-point sampling in formula (6) are as follows: respectively to multiple cokes of zoom lens
Away from the corresponding a value of its focal length is measured, the argument sequence of a value is formed；In actual use, according to the practical coke of zoom lens
Away from, using mathematical interpolation method calculate with real focal length corresponding to a mathematical approximation, further use the number of a of calculating
It learns approximation substitution (6) formula and correction calculating is carried out to the image of shooting.
4. the method for the correction of the lens distortion according to Claims 2 or 3, it is characterised in that: the actual photographed photo coordinate
(xd,yd) pixel color value using mathematical image interpolation algorithm calculate obtain；Described image interpolation algorithm includes that arest neighbors interpolation is calculated
Method or bilinear interpolation algorithm or cubic interpolation algorithm.
5. a kind of photographic means of lens distortion correction, it is characterised in that: including correcting parameter module, control module, camera lens mould
Block, sensor devices, image flame detection module, display module and memory module；The correction parameter module, control module, camera lens mould
Block, sensor devices and image flame detection module are sequentially connected electrically；The control module, image flame detection module and display module are successively electric
Connection；The control module, display module and memory module are sequentially connected electrically；The control module is mutually electrically connected with memory module
It connects.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910827446.4A CN110533618B (en) | 2019-09-03 | 2019-09-03 | Lens distortion correction method and photographic device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910827446.4A CN110533618B (en) | 2019-09-03 | 2019-09-03 | Lens distortion correction method and photographic device |
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