KR101637552B1 - Apparatus and Method for compensating irregular image for lense - Google Patents

Abstract

The present invention relates to an apparatus and method for correcting an image acquired through a lens.
The present invention is characterized in that a reference image for image correction is measured by transmitting a correction reference light to a lens module including at least one lens and a correction array for correcting a light transmission characteristic of the lens module by analyzing the measured reference image, The image captured by the sensor unit is transmitted through the lens module using the correction array, and the second-order offset correction is performed on the primary-corrected image. Thus, And a method thereof.

Description

[0001] The present invention relates to an apparatus and method for compensating an irregular image caused by a lens,

The present invention relates to an apparatus and method for correcting an image acquired through a lens.

2. Description of the Related Art Generally, an apparatus for acquiring an image including an infrared image includes a lens module for condensing light and a sensor module for converting light condensed through the lens module into an electric signal.

In this image capturing apparatus, the light transmission characteristic of the lens changes according to the ambient temperature. Also, the amount of light passing through the lens module and sensed by the sensor portion varies depending on how far each pixel of the sensor portion is located from the lens of the lens module. That is, the image acquired by the sensor unit is influenced by the distance between the lens and the lens, and becomes uneven. Therefore, it is necessary to remove the influence of the lens and correct the uneven image to obtain a uniform image.

In the conventional image correction method, after a lens or a lens module is placed in a room capable of temperature control and the change in the characteristics of the lens is measured while changing the temperature experimentally, And a method of correcting the image was used.

However, this conventional image correction method requires a separate experimental room capable of temperature control, and it takes a long time to measure the characteristic change according to the temperature of the lens. In case of measurement error caused by the experimenter in the test measurement, There is a problem that the correction result may be wrong.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method and an apparatus for measuring a reference image for image correction by transmitting a correction reference light to a lens module including at least one lens and analyzing the measured reference image to correct a light- Corrects the image acquired by the sensor unit by passing through the lens module using the correction array, performs second-order offset correction on the first-corrected image, and obtains high accuracy in a short time The present invention also provides an apparatus and method for correcting a non-uniform image caused by a lens while maintaining a good image quality.

According to an aspect of the present invention, there is provided an apparatus for correcting a non-uniform image using a lens, comprising: a sensor unit for measuring a reference light beam passing through an external lens module to obtain a reference image for image correction; And a correction unit that calculates correction information corresponding to a light transmission characteristic of the lens module for correcting an image obtained through the lens module using the reference image acquired by the sensor unit.

Here, the apparatus for correcting a non-uniform image using the lens may further include a light emitting unit for generating the correction reference light and making the light enter the lens module.

Here, the non-uniform image correcting device using the lens may further include: a blocking film for blocking external light to measure the correction reference light; And a lens module holder for holding the lens module and adjusting a distance between the lens module and the sensor unit.

Herein, the correction information includes a correction array having a predetermined size and an offset correction value, the correction unit estimates an approximate curve approximating the signal size of the reference image using the reference image, and uses the estimated approximate curve And calculating the correction arrangement and the offset correction value.

Here, the correcting unit may include: an estimating unit that estimates the approximate curve using the reference image; A correction array calculation unit for calculating a value of each element of the correction array using the estimated approximate curve; And an offset correction value calculation unit for calculating the offset correction value using the correction array.

Here, the estimating unit sets the center of the reference image, sets a distance between the reference image pixel and the center of the reference image as a first variable, and sets a signal size of the pixel of the reference image as a second variable And the magnitude variation of the second variable according to the first variable is estimated by the approximation curve, and the approximation curve is a first order or higher order polynomial.

Here, the correction array calculation unit may set the size of the correction array in consideration of the number of sensor pixels of the sensor unit, set the center of the correction array as a reference point of the approximate curve, and, for each element of the correction array, And calculating a value of the element of the correction array by using a value calculated by substituting the approximation curve for a distance from the element of the correction array to the center of the correction array.

Here, the offset correction value calculation unit may calculate an average of values of the elements of the correction array, and calculate the offset correction value using the calculated average value.

Here, the sensor unit acquires a correction target image to be corrected as an image of a subject, and the correction unit corrects the correction target image acquired by the sensor unit using the correction information .

Wherein the correction unit performs a primary correction by applying the correction array to the correction object image, performs a secondary correction by applying the offset correction value to the primary correction result, And an image correction processing unit for acquiring an image.

According to another aspect of the present invention, there is provided a method for correcting a non-uniform image using a lens, comprising: measuring a correction reference light passing through an external lens module using an image sensor to obtain a reference image for image correction; A correction reference image acquiring step; Estimating an approximate curve approximating a signal size of the reference image using the reference image; A correction array calculating step of calculating a correction array having a predetermined size by using the estimated approximate curve; And an offset correction value calculation step of calculating an offset correction value using the correction array.

Here, the estimating step sets a center part of the reference image, sets a distance of a pixel of the reference image away from a central part of the reference image as a first variable, and adjusts a signal size of the pixel of the reference image as a second variable And estimating a magnitude variation of the second variable according to the first variable with the approximate curve, wherein the correction array calculating step sets the size of the correction array in consideration of the sensor pixel number of the sensor unit, A center portion of the correction array is set as a reference point of the approximate curve and a distance from an element of the correction array to a center portion of the correction array is substituted for the approximate curve for each element of the correction array, Wherein the offset correction value calculation step calculates an average value of the elements of the correction array, And the offset correction value is calculated using the average value.

Here, the nonuniform image correcting method using the lens may be configured to obtain a correction target image to be corrected as an image of a subject photographed using the image sensor, and to obtain the correction target image using the correction array and the offset correction value, And an image correction processing step of correcting the corrected image data.

According to an aspect of the present invention, there is provided an apparatus and method for correcting a heterogeneous image using a lens, the method comprising: measuring a reference image for image correction by transmitting a correction reference light through a lens module including at least one lens; Acquiring a correction array for correcting a light transmission characteristic of the module, transmitting the lens module through the correction array to first correct the image acquired by the sensor unit, and performing second-order offset correction on the first-corrected image Thereby, there is an effect of correcting the non-uniform image caused by the lens with high accuracy in a short time and efficiently.

1 is a block diagram of an apparatus for correcting a non-uniform image using a lens according to an embodiment of the present invention.
FIG. 2 is a detailed block diagram of a correction unit of a non-uniform image correction apparatus using a lens according to the present invention.
FIG. 3 is a reference diagram for explaining the operation of the estimation unit of the non-uniform image correction apparatus using the lens according to the present invention.
FIG. 4 is a reference diagram for explaining the operation of the correction array calculation unit among the non-uniform image correction apparatus using the lens according to the present invention.
5 is a reference diagram for explaining the operation of the offset correction value calculating unit of the apparatus for correcting a non-uniform image by the lens according to the present invention.
6 is a reference view of an apparatus for correcting a non-uniform image using a lens according to an embodiment of the present invention.
7 is a flowchart illustrating a method of correcting a nonuniform image by a lens according to an embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the drawings, the same reference numerals are used to designate the same or similar components throughout the drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear. In addition, the preferred embodiments of the present invention will be described below, but it is needless to say that the technical idea of the present invention is not limited thereto and can be variously modified by those skilled in the art.

1 is a block diagram of an apparatus for correcting a non-uniform image using a lens according to an embodiment of the present invention.

The non-uniform image correcting apparatus using the lens may include a light emitting unit 100, a sensor unit 200, and a correcting unit 300. Here, the light emitting unit 100 may be omitted if necessary, and the non-uniform image correcting apparatus using the lens according to another embodiment of the present invention may include the sensor unit 200 and the correcting unit 300.

Hereinafter, each operation of the light emitting unit 100, the sensor unit 200, and the correcting unit 300 will be described in detail.

The light emitting unit 100 generates correction reference light and makes it enter the lens module.

The sensor unit 200 measures the correction reference light passing through the lens module to obtain a reference image for image correction.

Here, the correction reference light generated by the light emitting unit 100 may change the wavelength band and the intensity of the light considering the characteristics of the lens module. Further, the correction reference light may be a laser having a single wavelength band, and may be a white light if necessary.

Here, the correction reference light passing through the lens module may have a characteristic in which the intensity at the central portion of the lens included in the lens module is large, and the intensity becomes weaker toward the peripheral portion of the lens. Accordingly, the magnitude of the signal at the center of the reference image corresponding to the central portion of the reference image obtained by the sensor unit 200 according to the correction reference light is large, and the signal is weaker at the center of the reference image Characteristics can be shown.

Here, the intensity of the correction reference light that has passed through the lens module and the magnitude of the signal of the reference image change in accordance with the distance from the center as described above, and the light transmission characteristic of the lens module changes according to the ambient temperature of the lens module You can also change it as you go.

That is, since the intensity of the light passing through the lens module varies with the distance from the center of the lens module and is also influenced by the ambient temperature of the lens module, the reference image acquired by the sensor unit 200 has non-uniformity . The nonuniformity of the image due to the light transmission characteristic of the lens module unit is not displayed only on the reference image obtained according to the correction reference light, but a general subject is photographed using the lens module, and the sensor unit 200 photographs The same occurs also in the case of acquiring an image. That is, the image acquired by the sensor unit 200 with respect to the subject is influenced by the distance from the center of the lens module and the ambient temperature, and nonuniformity occurs.

In order to correct the nonuniformity of the image measured by the sensor unit 200 as described above, the apparatus for correcting a non-uniform image using the lens according to the present invention first generates the correction reference light in the light emitting unit 100, enters the lens module, The sensor unit 200 measures the reference light that has passed through the lens module to acquire the reference image. The calibration unit 300 analyzes the reference image, and acquires the image obtained by the sensor unit 200 according to the lens module It is preferable to calculate the correction information corresponding to the light transmission characteristic of the lens module for correcting the non-uniformity of the lens module. Next, the correction unit 300 can correct the non-uniformity in the image obtained from the object light reflected from the general subject and incident on the lens module using the correction information calculated as above.

The correction unit 300 calculates correction information corresponding to the light transmission characteristic of the lens module for correction of an image obtained through the lens module using the reference image acquired by the sensor unit 200. [

The correction information may include a correction array having a fixed size and an offset correction value.

Here, it is preferable that the corrector 300 estimates an approximate curve approximating the signal size of the reference image using the reference image, and calculates the correction array and the offset correction value using the estimated approximate curve.

Herein, the correction arrangement is a two-dimensional arrangement or more, preferably a two-dimensional arrangement, applied to the reference image to correct the non-uniformity of the reference image.

Here, the offset correction value is a value used for correcting the entire reference image by applying an offset value.

Hereinafter, the correction unit 300 will be described in more detail.

2 is a detailed block diagram of the correcting unit 300. As shown in FIG.

The correction unit 300 may include an estimation unit 310, a correction array calculation unit 320, and an offset correction value calculation unit 330.

The estimator 310 estimates the approximate curve using the reference image.

The correction array calculating unit 320 may calculate the value of each element of the correction array using the estimated approximate curve.

The offset correction value calculation unit 330 preferably calculates the offset correction value using the correction array.

Hereinafter, the operations of the estimation unit 310, the correction array calculation unit 320, and the offset correction value calculation unit 330 will be described in detail.

The estimating unit 310 sets the center of the reference image and sets a distance between the center of the reference image and a center of the reference image as a first variable and a size of a signal of the pixel of the reference image as a second variable And estimating a magnitude change of the second variable according to the first variable by the approximate curve.

Here, the approximation curve is preferably a polynomial of a first order or higher order.

For example, the approximation curve may be a third-order polynomial as shown in the following equation (1).

(Where x is the first variable, Y is the second variable, and a , b , c , and d are the respective coefficients of the polynomial).

Here, the estimator 310 estimates the approximate curve by calculating a coefficient of the polynomial of the approximate curve to estimate an approximate curve according to the polynomial.

3 is a reference diagram for explaining the operation of the estimation unit 310. As shown in FIG.

For example, as shown in FIG. 3, when the magnitude of the signal at the center of the reference image is large and the signal size decreases as the distance from the center increases, the approximation curve according to the reference image is expressed as x is near 0, the more the Y x is increased to have the maximum value Y has a value can be estimated by the curve that decreases drawing a curve.

The lens included in the lens module has a circular shape with respect to the center portion and may have a radially symmetrical structure. In this case, the light transmission characteristic of the lens may also have a radially symmetrical characteristic with respect to the central portion, and as a result, the intensity of the light transmitted through the lens may also have a radially symmetrical characteristic with respect to the central portion of the lens.

Therefore, the estimation unit 310 sets one approximation curve, determines one representative line extending from the central portion of the reference image to the peripheral portion, and determines a representative line corresponding to the distance from the center (the first variable) The change of the signal size of the reference image (the second variable) can be estimated by the approximate curve.

If necessary, the estimator 310 sets one approximation curve for more accurate estimation of the approximate curve, determines two or more representative lines from the central portion to the peripheral portion of the reference image, (Second variable) of the reference image according to the distance from the center (the first variable) in consideration of the distance from the center of the reference image to the approximate curve.

In order to estimate the approximate curve more precisely, the estimator 310 determines two or more representative lines from the central portion to the peripheral portion of the reference image, sets the approximate curves corresponding to the respective representative lines, , The variation of the signal magnitude (second variable) of the reference image according to the representative lines and the distance from the center (the first variable) to each of the approximate curves may be estimated by the approximate curve.

The correction array calculating unit 320 sets the size of the correction array in consideration of the number of sensor pixels of the sensor unit 200, sets the center of the correction array as a reference point of the approximate curve, It is preferable that a value of an element of the correction array is calculated using a value calculated by substituting a distance from the element of the correction array to the center of the correction array to the approximate curve with respect to the element.

Here, the correction array calculating unit 320 sets the center of the correction array as the zero point of the first variable, which is the reference point of the approximate curve, and for each element of the correction array, Calculating a value of the second variable of the approximate curve corresponding to the inputted first variable by inputting the distance to the center of the array as the first variable of the approximate curve, The value obtained by subtracting the value of the second variable from the value of the element of the correction array.

Here, the reference constant of the constant size may be a maximum signal value at the center of the reference image.

Here, the correction array calculating unit 320 may calculate the values of the elements of the correction array as shown in the following equations (2) and (3).

(Where CM is the correction sequence, K is the reference constant of the constant size, i , j is a variable indicating the index of the element in the correction array, and Y ( x ) Curve.)

(Where, x and D ( i , j ) are the distances from the center of the correction array to the elements corresponding to the index ( i , j ) of the correction array, N and M are the lengths of the sides of the correction array, n and m are constants for adjusting the center position of the correction array, and Q is a constant constant size.)

That is, in Equation (3), the size of the correction array is N x M , n and m are constants added to the index of the correction array to adjust the center point in calculating the distance from the center of the correction array , Q is a constant that is multiplied in order to scale the unit difference between the distance calculated according to the index of the correction array and the first variable in the regression curve.

Preferably, the correction arrangement may have a size proportional to the number of sensor pixels included in the sensor unit 200. For example, when the number of sensor pixels of the sensor unit 200 is 1080 x 720, the size of the correction array may be 1080 x 720.

FIG. 4 is a reference diagram for explaining the operation of the correction array calculation unit 320. FIG. According to FIG. 4, for example, the sensor pixel number of the sensor unit 200 may be 12 x 12, and the size of the reference image acquired in accordance with the sensor unit 200 may be 12 x 12. The approximate curve for the signal value according to the distance from the center of the reference image can be estimated by the estimation unit 310. [ In this case, the correction array may be set to a size of 12 x 12 according to the number of sensor pixels of the sensor unit 200. Here, when the distance corresponding to each element of the correction array is substituted into the regression curve as the first variable, the correction array calculating unit 320 calculates the value of the second variable corresponding to the distance, The value obtained by subtracting the calculated value of the second variable from the value of each element of the correction array. For example, the correction array calculated by the correction array calculation unit 320 may be calculated to have a distribution having the same size as the graph 1 of FIG.

It is preferable that the offset correction value calculating unit 330 calculates an average of the values of the elements of the correction array and calculates the offset correction value using the calculated average value.

Here, the offset correction value is preferably the calculated average value.

5 is a reference diagram for explaining the operation of the offset correction value calculation unit 330. In FIG. The graph 1 of FIG. 5 is a graph corresponding to the correction array, and it can be confirmed that the signal value has a uniform overall offset. Accordingly, an average value of the correction arrays is calculated and is used as the offset correction value, and the offset correction value is added to the reference image together with the correction array, thereby obtaining a uniform image as shown in the graph 2 of FIG.

As described above, the correction unit 300 can calculate the correction array and the offset correction value, which are correction information for correcting the non-uniform image caused by the lens.

Next, an operation of the correcting unit 300 for correcting an image of a subject photographed using the correction array and the offset correction value will be described.

First, the sensor unit 200 can acquire a correction target image to be corrected as an image of a photographed subject.

The correction unit 300 may correct the correction target image acquired by the sensor unit 200 using the correction information.

Here, the correction unit 300 performs a primary correction by applying the correction arrangement to the correction target image, applies the offset correction value to the primary correction result to perform secondary correction, And an image correction processing unit 340 for obtaining a corrected image.

Here, the image correction processing unit 340 may perform the primary correction by adding the correction array to the correction target image, perform the secondary correction by adding the offset correction value to the primary correction result, and correct the correction target image have.

Alternatively, the image correction processing unit 340 performs a primary correction by adding a value obtained by performing a conversion operation on the correction array to the correction object image, and a value obtained by performing a conversion operation on the offset correction value on the primary correction result The correction target image may be corrected by performing the secondary correction.

6 is a reference view of an apparatus for correcting a non-uniform image using a lens according to an embodiment of the present invention.

The apparatus for correcting a non-uniform image using a lens according to an embodiment of the present invention is configured as shown in FIG. 6A. First, the correction unit 300 calculates the correction information using the correction reference light and the reference image 6 (b), the correction unit 300 can correct the correction target image acquired from the subject by the sensor unit 200 using the calculated correction information.

The apparatus for correcting a non-uniform image using a lens according to an embodiment of the present invention may further include a shielding film for shielding external light so that the sensor unit 200 measures the reference light, And a lens module holder for adjusting the distance to the sensor unit 200.

6 (a), the non-uniform image correcting apparatus may include a light emitting unit 100, a lens module holder, a shielding film, a sensor unit 200, and a correcting unit 300. Here, the lens module can be mounted on a lens module mount which can be adjusted up and down.

7 is a flowchart illustrating a method of correcting a nonuniform image by a lens according to an embodiment of the present invention.

The non-uniform image correction method using the lens may include a correction reference image acquisition step (S100), an estimation step (S200), a correction array calculation step (S300), and an offset correction value calculation step (S400). The non-uniform image correcting method using the lens can operate in the same manner as the non-uniform image correcting apparatus using the lens according to the embodiment of the present invention described above. Therefore, in the following, a description will be given of a method of correcting the non-uniform image by the lens by omitting duplicate parts of the apparatus.

The correction reference image acquiring step (S100) acquires a reference image for image correction by measuring a correction reference light passing through an external lens module using an image sensor.

The estimating step S200 estimates an approximate curve by approximating the signal size of the reference image using the reference image.

Herein, the estimating step S200 may include setting a center of the reference image, setting a distance between the reference image pixel and the center of the reference image as a first variable, And estimating a magnitude change of the second variable according to the first variable by the approximate curve.

The correction array calculation step S300 calculates a correction array having a predetermined size using the estimated approximate curve.

Here, the correction array calculation step S300 may set the size of the correction array in consideration of the number of sensor pixels of the sensor unit 200, set the center of the correction array as a reference point of the approximate curve, It is preferable that for each element, the value of the element of the correction array is calculated by using a value calculated by substituting the approximation curve for the distance from the element of the correction array to the center of the correction array.

The offset correction value calculation step (S400) calculates the offset correction value using the correction array.

Here, it is preferable that the offset correction value calculation step (S400) calculates the average of the values of the elements of the correction array, and calculates the offset correction value using the calculated average value.

Here, the non-uniform image correction method using the lens may include a step of acquiring a correction target image to be corrected as an image of a subject photographed using an image sensor, and correcting the correction target image using the correction array and the offset correction value And an image correction processing step S500.

It is to be understood that the present invention is not limited to these embodiments, and all elements constituting the embodiment of the present invention described above are described as being combined or operated in one operation. That is, within the scope of the present invention, all of the components may be selectively coupled to one or more of them.

In addition, although all of the components may be implemented as one independent hardware, some or all of the components may be selectively combined to perform a part or all of the functions in one or a plurality of hardware. As shown in FIG. In addition, such a computer program may be stored in a computer readable medium such as a USB memory, a CD disk, a flash memory, etc., and read and executed by a computer to implement an embodiment of the present invention. As the recording medium of the computer program, a magnetic recording medium, an optical recording medium, a carrier wave medium, and the like can be included.

Furthermore, all terms including technical or scientific terms have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs, unless otherwise defined in the Detailed Description. Commonly used terms, such as predefined terms, should be interpreted to be consistent with the contextual meanings of the related art, and are not to be construed as ideal or overly formal, unless expressly defined to the contrary.

It will be apparent to those skilled in the art that various modifications, substitutions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims. will be. Therefore, the embodiments disclosed in the present invention and the accompanying drawings are intended to illustrate and not to limit the technical spirit of the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments and the accompanying drawings . The scope of protection of the present invention should be construed according to the following claims, and all technical ideas within the scope of equivalents should be construed as falling within the scope of the present invention.

100:
200:
300:
310:
320: correction array calculating section
330: Offset correction value calculation unit
340: image correction processing unit
S100: correction reference image acquisition step
S200: Estimation step
S300: Calculation array calculation step
S400: Offset correction value calculation step
S500: image correction processing step

Claims (13)

In the image correction apparatus,
A sensor unit for acquiring a reference image for image correction by measuring a correction reference light passing through an external lens module; And
And a correction unit for calculating correction information corresponding to a light transmission characteristic of the lens module for correcting an image obtained through the lens module using the reference image acquired by the sensor unit,
Wherein the correction information includes a correction array having a fixed size and an offset correction value,
The correction unit
Estimating an approximate curve approximating a signal size of the reference image using the reference image, setting a center of the reference image, setting a distance of the reference image to a center of the reference image as a first variable Estimating a magnitude variation of the second variable according to the first variable as the approximate curve with a magnitude of a signal of a pixel of the reference image as a second variable,
Calculating the correction array and the offset correction value using the estimated approximate curve, calculating a value of each element of the correction array using the estimated approximate curve, and calculating the offset correction value using the correction array and,
Characterized in that the approximate curve is a polynomial of a first order or higher order. The method according to claim 1,
And a light emitting unit for generating the correction reference light and making the light enter the lens module. 3. The method of claim 2,
A shielding layer for shielding external light to measure the correction reference light; And
Further comprising a lens module holder for holding the lens module and adjusting a distance between the lens module and the sensor unit. delete The apparatus according to claim 1,
An estimating unit estimating the approximate curve using the reference image;
A correction array calculation unit for calculating a value of each element of the correction array using the estimated approximate curve; And
And an offset correction value calculation unit for calculating the offset correction value using the correction sequence. 6. The apparatus according to claim 5,
Wherein a center of the reference image is set and a distance of a pixel of the reference image from the center of the reference image is set as the first variable and a signal size of the pixel of the reference image is set as the second variable, Estimating a magnitude change of the second variable according to one variable by the approximate curve,
Wherein the approximate curve is a first-order or higher-order polynomial. 6. The image processing apparatus according to claim 5,
Setting a size of the correction array in consideration of the number of sensor pixels of the sensor unit, setting a center of the correction array as a reference point of the approximate curve,
And for each element of the correction array, calculating a value of the element of the correction array using a value calculated by substituting the approximation curve for a distance from the element of the correction array to the center of the correction array Uneven image correction device by lens. The apparatus of claim 5, wherein the offset correction value calculation unit
Calculates an average value of the elements of the correction array, and calculates the offset correction value using the calculated average value. The method according to claim 1,
The sensor unit acquires a correction target image to be corrected as an image of a photographed subject,
Wherein the correction unit corrects the correction object image acquired by the sensor unit using the correction information. 10. The image processing apparatus according to claim 9,
An image correction processing unit for performing a primary correction by applying the correction array to the correction object image and performing a secondary correction by applying the offset correction value to the primary correction result to obtain an image obtained by correcting the correction object image, Further comprising a lens for correcting the uneven image. In the image correction method,
A correction reference image acquiring step of acquiring a reference image for image correction by measuring a correction reference light passing through an external lens module using an image sensor;
Estimating an approximate curve approximating a signal size of the reference image using the reference image;
A correction array calculating step of calculating a correction array having a predetermined size by using the estimated approximate curve; And
And an offset correction value calculation step of calculating an offset correction value using the correction array,
Wherein the estimating step sets a center of the reference image and sets a distance between a pixel of the reference image and a center of the reference image as a first variable and a size of a signal of the pixel of the reference image as a second variable, , Estimating a magnitude change of the second variable according to the first variable as the approximate curve,
Wherein the correction arrangement and the offset correction value are correction information corresponding to a light transmission characteristic of the lens module for correction of an image obtained through the lens module,
Wherein the approximate curve is a first-order or higher-order polynomial. 12. The method of claim 11,
Wherein the correction array calculation step sets the size of the correction array in consideration of the number of sensor pixels of the image sensor, sets the center of the correction array as a reference point of the approximate curve, Calculating a value of an element of the correction array by using a value calculated by substituting a distance from the element of the correction array to the center of the correction array to the approximate curve,
Wherein the offset correction value calculation step calculates an average of values of the elements of the correction array and calculates the offset correction value using the calculated average value. 13. The method of claim 12,
Further comprising an image correction processing step of acquiring a correction target image to be corrected as an image of the object photographed using the image sensor and correcting the correction target image using the correction array and the offset correction value Characterized in that the non-uniform image correction method using a lens.

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