CN116847211A

CN116847211A - Color filter array and interpolation method

Info

Publication number: CN116847211A
Application number: CN202310701068.1A
Authority: CN
Inventors: 张秀婉; 鲁五一; 伍倩莹; 陈兰兰
Original assignee: Guangzhou City Construction College
Current assignee: Guangzhou City Construction College
Priority date: 2023-06-13
Filing date: 2023-06-13
Publication date: 2023-10-03
Anticipated expiration: 2043-06-13
Also published as: CN116847211B

Abstract

The invention discloses a color filter array and an interpolation method, wherein, each row of basic units in a 4 multiplied by 4 format of the color filter array is respectively arranged in sequence: red, white, blue and green long exposure channels, white, green, white short exposure channels and green filter channels, blue, white long exposure channels, red and white long exposure channels, white short exposure channels, green, white short exposure channels and white short exposure channels, wherein the white long exposure channels are for receiving a greater exposure than the white short exposure channels. The color filter array has different white light exposure in the same working process, and the image obtained by interpolating the original data obtained by using the color filter array has the advantages of high dynamic range, high resolution and the like. The invention is widely applied to the technical field of image sensors.

Description

Color filter array and interpolation method

Technical Field

The invention relates to the technical field of image sensors, in particular to a color filter array and an interpolation method.

Background

The color filter array (Color Filter Array, CFA) can filter the color light with specific wavelength, so that the CCD or CMOS image sensor receives the filtered light, and good color reproduction capability, color signal-to-noise ratio and other effects are obtained.

The color filter array of the current mainstream is arranged in Bayer pattern (Bayer pattern), and in the color filter array of the pattern, the filter has limited perceptibility to a dark scene due to attenuation of light intensity, and larger noise can be generated in a dark area and is easy to cut off prematurely when the dark scene is shot. On the other hand, the bayer format arrangement of color filter arrays tends to limit the dynamic range of single frame scenes that can be acquired by the sensor.

Disclosure of Invention

Aiming at the technical problems that the current color filter array has limited perceptibility of a dim light scene, limited dynamic range of a single-frame scene and the like, the invention aims to provide a color filter array and an interpolation method.

In one aspect, embodiments of the present invention include a color filter array, wherein:

the color filter array includes a basic unit of a 4×4 format, which may be divided into a first unit block, a second unit block, a third unit block, and a fourth unit block, each of which is of a 2×2 format; inside the basic unit, the first unit block and the fourth unit block are in a diagonal position, and the second unit block and the third unit block are in a diagonal position;

The first unit block, the second unit block, the third unit block and the fourth unit block respectively comprise 1 white short exposure channel, 1 white long exposure channel and 1 green filtering channel; wherein, inside each of the first unit block, the second unit block, the third unit block and the fourth unit block, the white short exposure channel and the white long exposure channel are in opposite angles, and the relative positions of the green filter channels in the unit blocks are the same;

the first unit block and the fourth unit block respectively comprise 1 red filtering channel, and the second unit block and the third unit block respectively comprise 1 blue filtering channel; wherein, inside each of the first unit block and the fourth unit block, the red filter channel and the green filter channel are diagonally positioned with respect to each other; the blue filtering channel and the green filtering channel are in a diagonal position inside each of the second unit block and the third unit block;

the red filter channel is used for filtering components except red in incident light, the blue filter channel is used for filtering components except blue in the incident light, the green filter channel is used for filtering components except green in the incident light, the white long exposure channel and the white short exposure channel are respectively used for suppressing the incident light with all wavelengths to the same extent, and the white long exposure channel is used for receiving exposure larger than the white short exposure channel.

Further, the first row of the basic unit comprises a red filtering channel, a white long exposure channel, a blue filtering channel and a white long exposure channel which are sequentially arranged;

the second row of the basic unit comprises a white short exposure channel, a green filtering channel, a white short exposure channel and a green filtering channel which are sequentially arranged;

the third row of the basic unit comprises a blue filtering channel, a white long exposure channel, a red filtering channel and a white long exposure channel which are sequentially arranged;

the fourth row of the basic unit comprises a white short exposure channel, a green filtering channel, a white short exposure channel and a green filtering channel which are sequentially arranged;

the red filter channel is used for filtering components except red in the incident light, the blue filter channel is used for filtering components except blue in the incident light, the green filter channel is used for filtering components except green in the incident light, and the white long exposure channel is used for receiving a larger exposure than the white short exposure channel.

Further, the exposure time of the white long exposure channel is longer than the exposure time of the white short exposure channel, and: the exposure time of the white long exposure channel, the red filter channel, the blue filter channel and the green filter channel is the same, or the exposure time of the white short exposure channel, the red filter channel, the blue filter channel and the green filter channel is the same;

Or:

the transmittance of the white long exposure channel is greater than the transmittance of the white short exposure channel.

On the other hand, the embodiment of the invention further includes an interpolation method for interpolating a pixel point of an image sensor using the color filter array in the embodiment, where the interpolation method includes:

performing HDR synthesis on the white pixel points; the white pixel points comprise white long-exposure pixel points and white short-exposure pixel points, wherein the white long-exposure pixel points are pixel points corresponding to the white long-exposure channels, and the white short-exposure pixel points are pixel points corresponding to the white short-exposure channels;

performing white interpolation on the red pixel point, the blue pixel point and the green pixel point; the red pixel points are pixel points corresponding to the red filtering channels, the blue pixel points are pixel points corresponding to the blue filtering channels, and the green pixel points are pixel points corresponding to the green filtering channels;

performing green interpolation on the white pixel point, the red pixel point and the blue pixel point;

performing blue interpolation on the white pixel point, the red pixel point and the green pixel point;

Red interpolation is performed on the white pixel point, the blue pixel point, and the green pixel point.

Further, the performing HDR synthesis on the white pixel includes:

acquiring an exposure ratio alpha of the white long exposure channel relative to the white short exposure channel;

according to the formula

Determining a white pixel value of the white pixel point; wherein W is _L For the white pixel value of the white long exposure pixel point after HDR synthesis, W _s For the white pixel value of the white short exposure pixel adjacent to the white long exposure pixel after HDR synthesis, L is the luminance value of the white long exposure pixel before HDR synthesis, thr _high To highlight threshold Thr _low Is a low brightness threshold value, val _L To use the color filter array to shoot the gray scale card with uniform illumination, the value of the white long exposure channel, val _S In order to use the color filter array to shoot the gray scale card with uniform illumination, the value of the white short exposure channel, blc is the black level corresponding to the image sensor using the color filter array.

Further, the acquiring the exposure ratio α of the white long exposure channel relative to the white short exposure channel includes:

By the formulaOr->Performing calculation to obtain the exposure ratio alpha; wherein T is _L For the exposure time of the white long exposure channel, T _s Val is the exposure time of the white short exposure channel _L To use the color filter array to shoot the gray scale card with uniform illumination, the value of the white long exposure channel, val _S In order to use the color filter array to shoot the gray scale card with uniform illumination, the value of the white short exposure channel, blc is the black level corresponding to the image sensor using the color filter array.

Further, the performing white interpolation on the red pixel point, the blue pixel point, and the green pixel point includes:

according to the formula

Determining a white pixel value of the red pixel point, the blue pixel point or the green pixel point; wherein W is ₂₂ For the white pixel value of the red pixel, the blue pixel or the green pixel at a relative position 22 in the color filter array,horizontal gradient corresponding to pixel point with relative position 22 is represented by +.>Representing the vertical gradient corresponding to the pixel point with the relative position of 22, abs () represents taking the absolute value, W ₂₁ For the white pixel value, W, of the white pixel point of the color filter array with a relative position of 21 ₂₃ For the white pixel value, W, of the white pixel point of the color filter array at a relative position of 23 ₁₂ For the white pixel value, W, of the white pixel point of the color filter array with a relative position of 12 ₃₂ Thr represents a threshold value for the white pixel value of the white pixel point of the color filter array at a relative position of 32.

Further, the performing green interpolation on the white pixel point, the red pixel point, and the blue pixel point includes:

for the white short exposure pixel point, according to the formula

if

else if

else

Determining a green pixel value of the white short exposure pixel point; wherein G is ₃₂ For the green pixel value of the white short-exposure pixel point of the color filter array at a relative position of 32,horizontal gradient corresponding to pixel point with relative position of 32 is represented by +.>Representing the corresponding vertical gradient of the pixel point with a relative position of 32,abs () represents absolute value, W ₂₂ For the white pixel value, W, of the white pixel point of the color filter array at a relative position of 22 ₃₁ For the white pixel value, W, of the white pixel point of the color filter array with a relative position of 31 ₃₃ For the white pixel value, W, of the white pixel point of the color filter array at a relative position of 33 ₄₂ For the white pixel value of the white pixel point with a relative position of 42 in the color filter array, G ₁₁ G is the green pixel value of the green pixel point with the relative position of 11 in the color filter array ₁₃ G is the green pixel value of the green pixel point with the relative position of 13 in the color filter array ₃₁ G is the green pixel value of the green pixel point with the relative position of 31 in the color filter array ₃₃ G, which is the green pixel value of the green pixel point with the relative position of 33 in the color filter array ₅₁ G is the green pixel value of the green pixel point with the relative position of 51 in the color filter array ₅₃ A threshold value is represented by Thr for the green pixel value of the green pixel point of the color filter array with a relative position of 53;

for the white long exposure pixel point, according to the formula

if

else if

else

Determining a green pixel value of the white long-exposure pixel point; wherein G is ₂₃ For the green pixel value of the white long-exposure pixel point of the color filter array at a relative position of 23,horizontal gradient corresponding to pixel point with relative position 23 is represented by +.>Representing the vertical gradient corresponding to a pixel point with a relative position of 23, abs () represents taking the absolute value, W ₁₃ A white pixel value W for the white pixel point with a relative position of 13 in the color filter array ₂₂ For the white pixel value, W, of the white pixel point of the color filter array at a relative position of 22 ₂₄ For the white pixel value, W, of the white pixel point of the color filter array at a relative position of 24 ₃₃ For the white pixel value of the white pixel point with a relative position of 33 in the color filter array, G ₁₁ G is the green pixel value of the green pixel point with the relative position of 11 in the color filter array ₁₃ G is the green pixel value of the green pixel point with the relative position of 13 in the color filter array ₁₅ G is the green pixel value of the green pixel point with the relative position of 15 in the color filter array ₃₁ G is the green pixel value of the green pixel point with the relative position of 31 in the color filter array ₃₅ Green for the green pixel point of relative position 35 in the color filter arrayPixel value, G ₃₃ A threshold value is represented by Thr for the green pixel value of the green pixel point with a relative position of 33 in the color filter array;

for the red pixel point or the blue pixel point, according to the formula

Grad _A ＝|2*W ₂₂ -W ₁₃ -W ₃₁ |+|G ₁₃ -G ₃₁ |

Grad _D ＝|2*W ₂₂ -W ₁₁ -W ₃₃ |+|G ₁₁ -G ₃₃ |

if|Grad _A -Grad _D |<Thr：

else ifGrad _A <Grad _D

else

Determining a green pixel value of the red pixel point or the blue pixel point; wherein G is ₂₂ Grad is the green pixel value of the red pixel point or the blue pixel point with the relative position of 22 in the color filter array _A Represents the horizontal gradient corresponding to the pixel point with the relative position of 22, grad _D Representing the vertical gradient corresponding to the pixel point with the relative position of 22, abs () represents taking the absolute value, W ₁₁ A white pixel value W for the white pixel point with a relative position of 11 in the color filter array ₁₃ A white pixel value W for the white pixel point with a relative position of 13 in the color filter array ₂₂ For the white pixel value, W, of the white pixel point of the color filter array at a relative position of 22 ₃₁ For the white pixel value, W, of the white pixel point of the color filter array with a relative position of 31 ₃₃ For the white pixel value of the white pixel point with a relative position of 33 in the color filter array, G ₁₁ G is the green pixel value of the green pixel point with the relative position of 11 in the color filter array ₁₃ G is the green pixel value of the green pixel point with the relative position of 13 in the color filter array ₁₅ G is the green pixel value of the green pixel point with the relative position of 15 in the color filter array ₃₁ G is the green pixel value of the green pixel point with the relative position of 31 in the color filter array ₃₅ G is the green pixel value of the green pixel point with the relative position of 35 in the color filter array ₃₃ The threshold value is denoted Thr for the green pixel value of the green pixel point of the color filter array with a relative position of 33.

Further, the performing blue interpolation on the white pixel point, the red pixel point, and the green pixel point includes:

for the red pixel point, according to the formula

if

else if

else

Determining a blue pixel value of the red pixel point; wherein B is ₃₃ For the blue pixel value of the red pixel point of the color filter array at a relative position of 33,represents the horizontal gradient corresponding to the pixel point with the relative position of 33,representing the vertical gradient corresponding to the pixel point with the relative position of 33, abs () represents taking the absolute value, W ₁₃ A white pixel value W for the white pixel point with a relative position of 13 in the color filter array ₂₃ For the white pixel value, W, of the white pixel point of the color filter array at a relative position of 23 ₃₁ For the white pixel value, W, of the white pixel point of the color filter array with a relative position of 31 ₃₂ A white pixel value W for the white pixel point with a relative position of 32 in the color filter array ₃₃ For the white pixel value, W, of the white pixel point of the color filter array at a relative position of 33 ₃₄ For the white pixel value, W, of the white pixel point of the color filter array at a relative position of 34 ₃₅ A white pixel value W for the white pixel point with a relative position of 35 in the color filter array ₄₃ A white pixel value W for the white pixel point with a relative position 43 in the color filter array ₅₃ B is the white pixel value of the white pixel point with the relative position of 53 in the color filter array ₁₃ B, the blue pixel value of the blue pixel point with the relative position of 13 in the color filter array ₃₁ B, as the blue pixel value of the blue pixel point with the relative position of 31 in the color filter array ₃₅ B, the blue pixel value of the blue pixel point with the relative position of 35 in the color filter array ₅₃ For the blue pixel value of the blue pixel point with a relative position of 53 in the color filter array, thr represents a threshold value;

for the green pixel point, according to the formula

Determining a blue pixel value of the green pixel point; wherein B is ₂₂ B is the blue pixel value of the green pixel point with the relative position of 22 in the color filter array ₂₄ B is the blue pixel value of the green pixel point with the relative position of 24 in the color filter array ₄₂ B is the blue pixel value of the green pixel point with the relative position of 42 in the color filter array ₄₄ Blue pixel value, W, for the green pixel point of the color filter array at a relative position 44 ₁₁ A white pixel value W for the white pixel point with a relative position of 11 in the color filter array ₁₅ A white pixel value W for the white pixel point with a relative position of 15 in the color filter array ₂₂ For the white pixel value, W, of the white pixel point of the color filter array at a relative position of 22 ₂₄ Filtering the array for the colorWhite pixel value, W, of said white pixel point with a relative position of 24 ₃₃ For the white pixel value, W, of the white pixel point of the color filter array at a relative position of 33 ₄₂ A white pixel value W for the white pixel point of the color filter array with a relative position 42 ₄₄ A white pixel value W for the white pixel point with a relative position 44 in the color filter array ₅₁ A white pixel value W for the white pixel point with a relative position of 51 in the color filter array ₅₅ B is the white pixel value of the white pixel point with the relative position of 55 in the color filter array ₁₁ B, the blue pixel value of the blue pixel point with the relative position of 11 in the color filter array ₁₅ B, as the blue pixel value of the blue pixel point with the relative position of 15 in the color filter array ₃₃ B is the blue pixel value of the blue pixel point with the relative position of 33 in the color filter array ₅₁ B is the blue pixel value of the blue pixel point with the relative position of 51 in the color filter array ₅₅ A threshold value is represented by Thr for the blue pixel value of the blue pixel point with a relative position of 55 in the color filter array;

for the white pixel point, according to the formula

if

else if

else

Determining a blue pixel value of the white pixel point; wherein B is ₂₂ For the blue pixel value, W, of the white pixel point of the color filter array at a relative position of 22 ₁₂ For the white pixel value, W, of the white pixel point of the color filter array with a relative position of 12 ₂₁ For the white pixel value, W, of the white pixel point of the color filter array with a relative position of 21 ₂₂ For the white pixel value, W, of the white pixel point of the color filter array at a relative position of 22 ₂₃ For the white pixel value, W, of the white pixel point of the color filter array at a relative position of 23 ₃₂ B is the white pixel value of the white pixel point with the relative position of 32 in the color filter array ₁₂ A blue pixel value of a pixel point with a relative position of 12 in the color filter array, B ₂₁ A blue pixel value of a pixel point with a relative position of 21 in the color filter array, B ₂₃ A blue pixel value B for a pixel point with a relative position of 23 in the color filter array ₃₂ And the blue pixel value of the pixel point with the relative position of 32 in the color filter array.

Further, the interpolation method further includes:

for any pixel point, obtaining a red pixel value R, a green pixel value G, a blue pixel value B and a white pixel value W of the pixel point;

by the formulaCalculating gain valuegain；

According to the formula

Calculating a corrected red pixel valueCorrecting the green pixel value +.>And correcting the blue pixel value +.>

The beneficial effects of the invention are as follows: the color filter array in the embodiment is provided with the white long exposure channel (L) and the white short exposure channel (S) as channels of white light, so that different positions of the image sensor applying the color filter array have different white light exposure amounts in the same working process, thereby being beneficial to the image sensor to achieve a higher dynamic range and obtaining good image resolving power; the image obtained by interpolating the raw data obtained using the color filter array has the advantages of high dynamic range, high resolution, and the like.

Drawings

FIGS. 1 (a) and 1 (b) are schematic diagrams of the basic unit of a color filter array in an embodiment;

FIG. 2 is a step diagram of an interpolation method according to an embodiment;

fig. 3 (a) and 3 (b) are schematic views of two 2×2 units in the basic unit shown in fig. 1 (a);

FIG. 4 is a schematic diagram of the HDR synthesis of white pixels in the embodiment;

FIG. 5 is a schematic diagram showing the procedure of determining the green pixel value of the white short exposure pixel point according to the embodiment;

FIG. 6 is a schematic diagram showing a step of determining a green pixel value of a white long-exposure pixel in an embodiment;

fig. 7 is a schematic diagram of a step of determining a green pixel value of a red pixel or a blue pixel in the embodiment;

FIG. 8 is a schematic diagram of a step of determining a blue pixel value of a red pixel point according to an embodiment;

FIG. 9 is a schematic diagram of a step of determining a blue pixel value of a green pixel point according to an embodiment;

fig. 10 is a schematic diagram of a step of determining a blue pixel value of a white pixel point according to an embodiment.

Detailed Description

In this embodiment, the basic unit of the color filter array is a 4×4pattern, for example, a complete color filter array is obtained by sequentially combining a plurality of 4×4 patterns shown in fig. 1 (a) or fig. 1 (b).

For convenience of explanation, referring to fig. 1 (a) or 1 (b), one basic unit may be divided into 4 unit blocks of a first unit block, a second unit block, a third unit block, a fourth unit block, and the like, each unit block being in a 2×2 format, i.e., each unit block being composed of 4 channels. In the present embodiment, the "unit block" is a concept proposed for convenience of description of the structure of the basic unit, and does not mean that there is a necessary hierarchical relationship between the "basic unit" and the "unit block", or that different "unit blocks" are mutually independent entities.

Referring to fig. 1 (a) or 1 (b), inside the basic unit, the first unit block and the fourth unit block are positioned diagonally to each other, and the second unit block and the third unit block are positioned diagonally to each other, for example, the first unit block, the second unit block, the third unit block, and the fourth unit block are positioned at the upper left corner, the upper right corner, the lower left corner, and the lower right corner, respectively, inside the basic unit.

In this embodiment, the basic unit of one color filter array includes 16 channels, specifically including 4 white long exposure channels, 4 white short exposure channels, 4 green filter channels, 2 red filter channels, and 2 blue filter channels, which are respectively distributed in different unit blocks.

For example, either fig. 1 (a) or fig. 1 (b) is a possible channel arrangement.

Referring to fig. 1 (a) or 1 (b), the first, second, third and fourth unit blocks include 1 white short exposure channel (S), 1 white long exposure channel (L) and 1 green filter channel (G), respectively. Wherein, inside each of the first unit block, the second unit block, the third unit block and the fourth unit block, the white short exposure channel and the white long exposure channel are in opposite angles, and the relative positions of the green filter channels in the unit blocks are the same. For example, in the first, second, third, and fourth unit blocks, the green filter channels (G) are all located at the lower right corner position, while the white long exposure channels (L) are all located at the upper right corner (or lower left corner) position, and the white short exposure channels (S) are all located at the lower left corner (or upper right corner) position.

Referring to fig. 1 (a), the first and fourth unit blocks respectively include 1 red filter channel (R), and the second and third unit blocks respectively include 1 blue filter channel (B). Wherein, inside each of the first unit block and the fourth unit block, the red filter channel (R) and the green filter channel (G) are diagonally positioned with respect to each other; inside each of the second unit block and the third unit block, the blue filter channel (B) and the green filter channel (G) are diagonally positioned with respect to each other. For example, referring to fig. 1 (a), inside each of the first and fourth unit blocks, the red filter channel (R) is located at the upper left corner position; inside each of the second unit block and the third unit block, the blue filter channel (B) is located at the upper left corner position.

Referring to fig. 1 (B), the first unit block and the fourth unit block respectively include 1 blue filter channel (B), and the second unit block and the third unit block respectively include 1 red filter channel (R). Wherein, inside each of the first unit block and the fourth unit block, the blue filter channel (B) and the green filter channel (G) are diagonally positioned with respect to each other; inside each of the second unit block and the third unit block, the red filter channel (R) and the green filter channel (G) are diagonally positioned with respect to each other. For example, referring to fig. 1 (B), inside each of the first unit block and the fourth unit block, the blue filter channel (B) is located at the upper left corner position; inside each of the second and third unit blocks, the red filter channel (R) is located at the upper left corner position.

The channel arrangement shown in fig. 1 (a) and 1 (b) and other channel arrangements satisfying the relative relationship between the channels are all possible, and the same technical effects can be achieved, and in this embodiment, the channel arrangement shown in fig. 1 (a) is taken as an example, and the description about the principle and use etc. of fig. 1 (a) is equally applicable to the channel arrangement shown in fig. 1 (b) and other channel arrangements satisfying the relative relationship between the channels.

Referring to fig. 1 (a), the first row in the 4×4pattern includes a red filter channel (R), a white long exposure channel (L), a blue filter channel (B), and a white long exposure channel (L) arranged in this order; the second row comprises a white short exposure channel (S), a green filter channel (G), a white short exposure channel (S) and a green filter channel (G) which are sequentially arranged; the third row comprises a blue filter channel (B), a white long exposure channel (L), a red filter channel (R) and a white long exposure channel (L) which are sequentially arranged; the fourth row includes a white short-exposure channel (S), a green filter channel (G), a white short-exposure channel (S), and a green filter channel (G) arranged in this order.

Wherein the red filter channel (R) is used for filtering components other than red in the incident light, namely only allowing red light to pass through; the blue filter channel (B) is used for filtering components other than blue in the incident light, namely only allowing blue light to pass through; the green filter channel (G) is used for filtering components other than green in the incident light, namely, only allowing the green light to pass through; the white long exposure channel (L) and the white short exposure channel (S) may not be filtered out for any specific color, i.e. both the white long exposure channel and the white short exposure channel allow light of any color (white light) to pass through.

When the color filter array shown in fig. 1 (a) is used in an image sensor, and is operated, the white long exposure channel (L) receives a larger exposure than the white short exposure channel (S), i.e., each exposure, the pixel corresponding to the white long exposure channel (L) on the image sensor receives a larger exposure than the pixel corresponding to the white short exposure channel (S).

In the color filter array shown in fig. 1 (a), the basic unit of the 4×4pattern contains 4 white long exposure channels (L), 4 white short exposure channels (S) (8 white channels in total), 4 green filter channels (G), 2 red filter channels (R), and 2 blue filter channels (B), that is, the white pixel ratio is 50%, the green pixel ratio is 25%, and the red pixel and blue pixel ratio are 12.5%. Because the white long exposure channel (L) and the white short exposure channel (S) are simultaneously arranged as channels of white light, different positions of the image sensor applying the color filter array have different exposure amounts of the white light in the same working process, thereby being beneficial to the image sensor to achieve higher dynamic range and obtaining good image resolving power.

In the present embodiment, the characteristic that the "white long exposure channel (L) receives a larger exposure amount than the white short exposure channel (S)" can be achieved by:

Mode 1: the exposure time of the white long exposure channel (L) is longer than the exposure time of the white short exposure channel (S);

mode 2: the transmittance of the white long exposure channel (L) is greater than the transmittance of the white short exposure channel (S).

In mode 1, the exposure time of each channel of the color filter array (or the corresponding pixel in the image sensor) may be individually controlled so that the exposure time of the white long exposure channel (L) is longer than the exposure time of the white short exposure channel (S) at each exposure. Specifically, mode 1 has the following two cases:

(1) The exposure time of the white long exposure channel (L), the red filter channel (R), the blue filter channel (B) and the green filter channel (G) are the same, and are all larger values, and the exposure time of the white short exposure channel (S) is a smaller value. In this case, it is advantageous for the image sensor to obtain more information in the highlight scene.

(2) The exposure time of the white short exposure channel (S), the red filter channel (R), the blue filter channel (B) and the green filter channel (G) are the same, and are smaller, and the exposure time of the white long exposure channel (L) is larger. This is advantageous in that the image sensor obtains more dark field detail in dark scenes.

In the mode 2, the attenuation sheet can be added on the white short exposure channel (S) independently, and the white long exposure channel (L) does not use the attenuation sheet, so that the transmissivity of the white short exposure channel (S) is reduced, the transmissivity of the white long exposure channel (L) is lower than that of the white short exposure channel (S), and the image sensor can obtain more information under a highlight scene.

For the image sensor of the color filter array in the present embodiment, an interpolation method as shown in fig. 2 is provided to interpolate pixel points in the image sensor. Referring to fig. 2, the interpolation method includes the steps of:

s1, performing HDR synthesis on white pixel points;

s2, white interpolation is carried out on the red pixel point, the blue pixel point and the green pixel point; the red pixel points are pixel points corresponding to the red filtering channels, the blue pixel points are pixel points corresponding to the blue filtering channels, and the green pixel points are pixel points corresponding to the green filtering channels;

s3, green interpolation is carried out on the white pixel point, the red pixel point and the blue pixel point;

s4, blue interpolation is carried out on the white pixel point, the red pixel point and the green pixel point;

s5, red interpolation is carried out on the white pixel point, the blue pixel point and the green pixel point.

In steps S1 to S5, when the color filter array is applied to the image sensor, the pixel point corresponding to the white long exposure channel (L) on the image sensor is referred to as a white long exposure pixel point, the pixel point corresponding to the white short exposure channel (S) is referred to as a white short exposure pixel point, the pixel point corresponding to the red filter channel (R) is referred to as a red pixel point, the pixel point corresponding to the blue filter channel (B) is referred to as a blue pixel point, and the pixel point corresponding to the green filter channel (G) is referred to as a green pixel point. The white long-exposure pixel point and the white short-exposure pixel point are both sensitive to white light, so the white long-exposure pixel point and the white short-exposure pixel point can be collectively called a white pixel point.

In performing step S1, that is, performing the HDR synthesis on the white pixel, the following steps may be specifically performed:

s101, acquiring an exposure ratio alpha of a white long exposure channel relative to a white short exposure channel;

s102, determining the white pixel value of the white pixel point according to the formula (1).

In step S101, for the color filter array implemented in mode 1, the color filter array can be obtained by the formulaCalculating an exposure ratio alpha, wherein T _L Exposure time for white long exposure channel, T _s Exposure time for a white short exposure channel; for the color filter array implemented by means 2, it is possible to apply the formula +.>Calculating an exposure ratio alpha, wherein Val _L Values of white long exposure channel obtained by calibrating color filter array (for example, shooting gray card with uniform illumination) Val _S In order to calibrate the color filter array, the obtained value of the white short exposure channel is blc, which is the black level corresponding to the image sensor when the color filter array is calibrated.

After the exposure ratio α is obtained by executing step S101, for the case shown in fig. 1 (a)Basic units from which two 2 x 2 units as shown in fig. 3 (a) and 3 (b) can be obtained. For these two 2×2 cells, step S102 is performed to set a highlight threshold Thr _high And a low brightness threshold Thr _low Calculation is performed by the formula (1), wherein W _L To synthesize the white pixel value of the white long exposure pixel point by HDR, W _S For the white pixel value of the white short exposure pixel adjacent to the white long exposure pixel after the HDR synthesis, L is the luminance value of the white long exposure pixel before the HDR synthesis.

By executing step S1, pixel values of pixel points corresponding to half channels (i.e., a white long-exposure channel and a white short-exposure channel) in the basic unit shown in fig. 1 (a) can be calculated, so as to provide data for performing interpolation in steps S2-S5.

In the present embodiment, the interpolation performed in steps S2 to S5 is a process of calculating an undetected pixel value from a point where the pixel value is detected in the image sensor. For example, in step S3, the green pixel point in the image sensor can detect the green pixel value, but the white pixel point, the red pixel point and the blue pixel point do not detect the green pixel value, so the green pixel values corresponding to the white pixel point, the red pixel point and the blue pixel point can be calculated respectively through interpolation. By executing steps S2-S5, each pixel in the image sensor has its corresponding four different color pixel values, e.g., any one of the green pixel in the image sensor has its corresponding green pixel value, white pixel value, red pixel value, and blue pixel value, wherein the green pixel value is detected by the green pixel, and the white pixel value, red pixel value, and blue pixel value are interpolated.

In performing step S2, that is, performing white interpolation on the red pixel, the blue pixel, and the green pixel, the following steps may be specifically performed:

s201, determining white pixel values of red pixel points, blue pixel points or green pixel points according to formulas (2) and (3).

In the formulas (2) and (3), W ₂₂ For the white pixel value of the red pixel, blue pixel or green pixel at a relative position 22 in the color filter array,representing the horizontal gradient corresponding to the pixel point at relative position 22,representing the vertical gradient corresponding to the pixel point with the relative position of 22, abs () represents taking the absolute value, W ₂₁ White pixel value W for white pixel point with relative position 21 in color filter array ₂₃ White pixel value, W, for a white pixel point of 23 relative positions in the color filter array ₁₂ White pixel value W for white pixel point with relative position of 12 in color filter array ₃₂ The threshold value is denoted Thr, which is the white pixel value of the white pixel point of the color filter array with a relative position of 32.

When the calculation is performed according to the formulas (2) and (3), the relative positions of the respective pixel points are as shown in fig. 4. Fig. 4 is a part of a color filter array using the 4×4pattern shown in fig. 1 (a) as a basic unit, and in this embodiment, including fig. 4, in describing the position, a channel (or a pixel point in a corresponding image sensor) with x-axis and y-axis in the color filter array is represented in the form of "xy", and the positive direction of the abscissa is horizontal to the right, and the positive direction of the ordinate is vertical to the bottom. For example, in fig. 4, "relative position 23" indicates a channel (or a pixel point in a corresponding image sensor) of the 2 nd row from top to bottom and the 3 rd column from left to right.

Step S2 is executed for each of the red pixel point, the blue pixel point and the green pixel point, so that respective white pixel values of each of the red pixel point, the blue pixel point and the green pixel point can be obtained, thereby completing interpolation of the white pixel values.

In performing step S3, that is, performing green interpolation on the white pixel point, the red pixel point, and the blue pixel point, the following steps may be specifically performed:

s301, for the white short exposure pixel points, determining green pixel values of the white short exposure pixel points according to formulas (4) - (7);

if

else if

else

FIG. 5 shows the structure of FIG. 1 (a)The 4 x 4pattern shown is part of a color filter array of basic cells. In performing the calculations according to formulas (4) - (7), refer to FIG. 5, G ₃₂ Is the green pixel value of the white short-exposure pixel point with a relative position of 32 in the color filter array,horizontal gradient corresponding to pixel point with relative position of 32 is represented by +.>Representing the vertical gradient corresponding to a pixel point with a relative position of 32, abs () represents taking the absolute value, W ₂₂ White pixel value, W, for a white pixel point of relative position 22 in the color filter array ₃₁ White pixel value W of white pixel point with relative position of 31 in color filter array ₃₃ White pixel value, W, is the white pixel point of the color filter array at a relative position of 33 ₄₂ A white pixel value G for a white pixel point of 42 relative positions in the color filter array ₁₁ G is the green pixel value of the green pixel point with the relative position of 11 in the color filter array ₁₃ G is the green pixel value of the green pixel point with the relative position of 13 in the color filter array ₃₁ G is the green pixel value of the green pixel point with the relative position of 31 in the color filter array ₃₃ G is the green pixel value of the green pixel point with the relative position of 33 in the color filter array ₅₁ G is the green pixel value of the green pixel point with the relative position of 51 in the color filter array ₅₃ The threshold value is denoted Thr for the green pixel value of the green pixel point of the color filter array with a relative position of 53.

S302, for the white long exposure pixel point, determining a green pixel value of the white long exposure pixel point according to formulas (8) - (11);

if

else if/>

else

fig. 6 is a part of a color filter array having the 4×4pattern shown in fig. 1 (a) as a basic unit. In performing the calculations according to formulas (8) - (11), refer to FIG. 6, G ₂₃ For the green pixel value of the white long exposure pixel with a relative position of 23 in the color filter array,horizontal gradient corresponding to pixel point with relative position 23 is represented by +. >Representing the vertical gradient corresponding to a pixel point with a relative position of 23, abs () represents taking the absolute value, W ₁₃ White pixel value W of white pixel point with relative position 13 in color filter array ₂₂ White pixel value, W, for a white pixel point of relative position 22 in the color filter array ₂₄ White pixel value W for white pixel point with relative position 24 in color filter array ₃₃ For colour filter arraysWhite pixel value, G, of white pixel point with relative position 33 in column ₁₁ G is the green pixel value of the green pixel point with the relative position of 11 in the color filter array ₁₃ G is the green pixel value of the green pixel point with the relative position of 13 in the color filter array ₁₅ G is the green pixel value of the green pixel point with the relative position of 15 in the color filter array ₃₁ G is the green pixel value of the green pixel point with the relative position of 31 in the color filter array ₃₅ G is the green pixel value of the green pixel point with the relative position of 35 in the color filter array ₃₃ The threshold value is represented by Thr, which is the green pixel value of the green pixel point with the relative position of 33 in the color filter array;

s303, for the red pixel point or the blue pixel point, determining a green pixel value of the red pixel point or the blue pixel point according to formulas (12) - (15);

Grad _A ＝|2*W ₂₂ -W ₁₃ -W ₃₁ |+|G ₁₃ -G ₃₁ |

Grad _D ＝|2*W ₂₂ -W ₁₁ -W ₃₃ |+|G ₁₁ -G ₃₃ | (12)

if|Grad _A -Grad _D |<Thr：

else if Grad _A <Grad _D

else

Fig. 7 is a part of a color filter array having the 4×4pattern shown in fig. 1 (a) as a basic unit. In accordance with formulas (12) - (15)For calculation, refer to fig. 7,G ₂₂ For the red pixel point or the green pixel value of the blue pixel point with the relative position of 22 in the color filter array, grad _A Represents the horizontal gradient corresponding to the pixel point with the relative position of 22, grad _D Representing the vertical gradient corresponding to the pixel point with the relative position of 22, abs () represents taking the absolute value, W ₁₁ White pixel value W for a white pixel point of 11 relative positions in the color filter array ₁₃ White pixel value W of white pixel point with relative position 13 in color filter array ₂₂ White pixel value, W, for a white pixel point of relative position 22 in the color filter array ₃₁ White pixel value W of white pixel point with relative position of 31 in color filter array ₃₃ For the white pixel value of the white pixel point with the relative position of 33 in the color filter array, G ₁₁ G is the green pixel value of the green pixel point with the relative position of 11 in the color filter array ₁₃ G is the green pixel value of the green pixel point with the relative position of 13 in the color filter array ₁₅ G is the green pixel value of the green pixel point with the relative position of 15 in the color filter array ₃₁ G is the green pixel value of the green pixel point with the relative position of 31 in the color filter array ₃₅ G is the green pixel value of the green pixel point with the relative position of 35 in the color filter array ₃₃ The threshold value is denoted Thr for the green pixel value of the green pixel point with a relative position of 33 in the color filter array.

In this embodiment, step S301 is performed on each white short-exposure pixel point, so as to obtain a respective green pixel value of each white short-exposure pixel point; step S302 is executed for each white long exposure pixel point respectively, so that a respective green pixel value of each white long exposure pixel point can be obtained; step S303 is performed for each red pixel or each blue pixel, respectively, so that a respective green pixel value for each red pixel or each blue pixel can be obtained. Accordingly, by performing steps S301 to S303, the respective green pixel values of each of the white pixel point, the red pixel point, and the blue pixel point can be obtained, thereby completing the interpolation of the green pixel values.

In performing step S4, that is, performing blue interpolation on the white pixel point, the red pixel point, and the green pixel point, the following steps may be specifically performed:

s401, for the red pixel point, determining a blue pixel value of the red pixel point according to formulas (16) - (19);

if

else if

else

Fig. 8 is a part of a color filter array having the 4×4pattern shown in fig. 1 (a) as a basic unit. In performing the calculations according to formulas (16) - (19), refer to FIG. 8, B ₃₃ For the blue pixel value of the red pixel point with a relative position of 33 in the color filter array,pixel point pair representing relative position 33Horizontal gradient of response,/->Representing the vertical gradient corresponding to the pixel point with the relative position of 33, abs () represents taking the absolute value, W ₁₃ White pixel value W of white pixel point with relative position 13 in color filter array ₂₃ White pixel value, W, for a white pixel point of 23 relative positions in the color filter array ₃₁ White pixel value W of white pixel point with relative position of 31 in color filter array ₃₂ White pixel value W for white pixel point with relative position 32 in color filter array ₃₃ White pixel value, W, is the white pixel point of the color filter array at a relative position of 33 ₃₄ White pixel value, W, is the white pixel point of the color filter array at a relative position of 34 ₃₅ White pixel value W for a white pixel point of 35 relative positions in the color filter array ₄₃ White pixel value, W, is the white pixel point of the color filter array at a relative position of 43 ₅₃ A white pixel value of a white pixel point with a relative position of 53 in the color filter array, B ₁₃ B is the blue pixel value of the blue pixel point with the relative position of 13 in the color filter array ₃₁ B is the blue pixel value of the blue pixel point with the relative position of 31 in the color filter array ₃₅ Blue pixel value of blue pixel point with relative position of 35 in color filter array, B ₅₃ The threshold value is denoted Thr for the blue pixel value of the blue pixel point of the color filter array with a relative position of 53.

S402, for the green pixel points, determining blue pixel values of the green pixel points according to formulas (20) - (23).

/>

Fig. 9 is a part of a color filter array having the 4×4pattern shown in fig. 1 (a) as a basic unit. In performing the calculations according to formulas (20) - (23), refer to FIG. 9, B ₂₂ Blue pixel value of green pixel point with relative position of 22 in color filter array, B ₂₄ Blue pixel value of green pixel point with relative position of 24 in color filter array, B ₄₂ Blue pixel value of green pixel point with relative position of 42 in color filter array, B ₄₄ Blue pixel value, W, of green pixel point with relative position 44 in color filter array ₁₁ White pixel value W for a white pixel point of 11 relative positions in the color filter array ₁₅ White pixel value W of white pixel point with relative position of 15 in color filter array ₂₂ White pixel value, W, for a white pixel point of relative position 22 in the color filter array ₂₄ White pixel value W for white pixel point with relative position 24 in color filter array ₃₃ White pixel value, W, is the white pixel point of the color filter array at a relative position of 33 ₄₂ White pixel value W for a white pixel point of 42 relative positions in the color filter array ₄₄ White pixel value, W, is the white pixel point of the color filter array at a relative position of 44 ₅₁ Is the white pixel value, W, of the white pixel point with the relative position of 51 in the color filter array ₅₅ B is the white pixel value of the white pixel point with the relative position of 55 in the color filter array ₁₁ B is the blue pixel value of the blue pixel point with the relative position of 11 in the color filter array ₁₅ B is the blue pixel value of the blue pixel point with the relative position of 15 in the color filter array ₃₃ Blue pixel value B for blue pixel point with relative position 33 in color filter array ₅₁ For filtering the phases in the arrayBlue pixel value, B, for blue pixel point at position 51 ₅₅ The threshold value is denoted Thr for the blue pixel value of the blue pixel point with a relative position of 55 in the color filter array.

S403, for the white pixel point, determining a blue pixel value of the white pixel point according to formulas (24) - (27).

if

else if

else

Fig. 10 is a part of a color filter array having the 4×4pattern shown in fig. 1 (a) as a basic unit. In performing the calculations according to formulas (20) - (23), refer to FIG. 10, B ₂₂ Blue pixel value, W, for a white pixel point of relative position 22 in the color filter array ₁₂ White pixel value W for white pixel point with relative position of 12 in color filter array ₂₁ For relative position in the color filter arrayWhite pixel value, W, of 21 white pixel point ₂₂ White pixel value, W, for a white pixel point of relative position 22 in the color filter array ₂₃ White pixel value, W, for a white pixel point of 23 relative positions in the color filter array ₃₂ A white pixel value B for a white pixel point with a relative position of 32 in the color filter array ₁₂ Blue pixel value of pixel point with relative position of 12 in color filter array, B ₂₁ Blue pixel value of pixel point with relative position of 21 in color filter array, B ₂₃ Blue pixel value of pixel point with relative position of 23 in color filter array, B ₃₂ Is the blue pixel value of the pixel point with the relative position of 32 in the color filter array.

In this embodiment, step S401 is performed for each red pixel point, so as to obtain a respective blue pixel value of each red; step S402 is executed for each green pixel point, so as to obtain a respective blue pixel value of each green pixel point; step S403 is performed for each white pixel point, respectively, and a respective blue pixel value for each white pixel point can be obtained. Thus, by performing steps S301 to S303, the respective blue pixel values of each of the green pixel point, the red pixel point, and the white pixel point can be obtained, thereby completing interpolation of the blue pixel values.

In the present embodiment, the principle of interpolation of the red pixel value is the same as that of the blue pixel value, and therefore, interpolation of the red pixel value can be performed with reference to steps S401 to S403. Specifically, the "red" and "blue" in steps S401 to S403 are swapped, and an interpolation process of the red pixel value is obtained.

By performing steps S1 to S5, pixel values of respective pixel points in the image sensor using the color filter array in the present embodiment can be obtained. Specifically, for any one pixel point, it has a red pixel value R, a green pixel value G, a blue pixel value B, and a white pixel value W obtained by detection or interpolation. On the basis of performing steps S1-S5, the following steps may also be performed:

S6, calculating a gain value gain through a formula (28);

s7, according to the formula(29) - (31) calculating corrected red pixel valueCorrecting the green pixel value +.>And correcting the blue pixel value +.>

In step S6, the calculated gain value gain is a Luma gain, and may be used to correct the red pixel value R, the green pixel value G, and the blue pixel value B of the pixel point, to obtain a red pixel valueCorrecting the green pixel value +.>And correcting the blue pixel value +.>Can be used as the corresponding output value of the pixel point.

By executing steps S1 to S4 and steps S5 to S6, the raw map acquired using the color filter array can be converted into RGB format. According to the principle of the color filter array in the present embodiment, the RGB format image obtained by performing the interpolation in steps S1-S4 has the advantages of high dynamic range and high resolution.

It should be noted that, unless otherwise specified, when a feature is referred to as being "fixed" or "connected" to another feature, it may be directly or indirectly fixed or connected to the other feature. Further, the descriptions of the upper, lower, left, right, etc. used in this disclosure are merely with respect to the mutual positional relationship of the various components of this disclosure in the drawings. As used in this disclosure, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. In addition, unless defined otherwise, all technical and scientific terms used in this example have the same meaning as commonly understood by one of ordinary skill in the art. The terminology used in the description of the embodiments is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and/or" as used in this embodiment includes any combination of one or more of the associated listed items.

It should be understood that although the terms first, second, third, etc. may be used in this disclosure to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element of the same type from another. For example, a first element could also be termed a second element, and, similarly, a second element could also be termed a first element, without departing from the scope of the present disclosure. The use of any and all examples, or exemplary language (e.g., "such as") provided herein, is intended merely to better illuminate embodiments of the invention and does not pose a limitation on the scope of the invention unless otherwise claimed.

It should be appreciated that embodiments of the invention may be implemented or realized by computer hardware, a combination of hardware and software, or by computer instructions stored in a non-transitory computer readable memory. The methods may be implemented in a computer program using standard programming techniques, including a non-transitory computer readable storage medium configured with a computer program, where the storage medium so configured causes a computer to operate in a specific and predefined manner, in accordance with the methods and drawings described in the specific embodiments. Each program may be implemented in a high level procedural or object oriented programming language to communicate with a computer system. However, the program(s) can be implemented in assembly or machine language, if desired. In any case, the language may be a compiled or interpreted language. Furthermore, the program can be run on a programmed application specific integrated circuit for this purpose.

Furthermore, the operations of the processes described in the present embodiments may be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The processes (or variations and/or combinations thereof) described in this embodiment may be performed under control of one or more computer systems configured with executable instructions, and may be implemented as code (e.g., executable instructions, one or more computer programs, or one or more applications), by hardware, or combinations thereof, that collectively execute on one or more processors. The computer program includes a plurality of instructions executable by one or more processors.

Further, the method may be implemented in any type of computing platform operatively connected to a suitable computing platform, including, but not limited to, a personal computer, mini-computer, mainframe, workstation, network or distributed computing environment, separate or integrated computer platform, or in communication with a charged particle tool or other imaging device, and so forth. Aspects of the invention may be implemented in machine-readable code stored on a non-transitory storage medium or device, whether removable or integrated into a computing platform, such as a hard disk, optical read and/or write storage medium, RAM, ROM, etc., such that it is readable by a programmable computer, which when read by a computer, is operable to configure and operate the computer to perform the processes described herein. Further, the machine readable code, or portions thereof, may be transmitted over a wired or wireless network. When such media includes instructions or programs that, in conjunction with a microprocessor or other data processor, implement the steps described above, the invention described in this embodiment includes these and other different types of non-transitory computer-readable storage media. The invention also includes the computer itself when programmed according to the methods and techniques of the present invention.

The computer program can be applied to the input data to perform the functions described in this embodiment, thereby converting the input data to generate output data that is stored to the non-volatile memory. The output information may also be applied to one or more output devices such as a display. In a preferred embodiment of the invention, the transformed data represents physical and tangible objects, including specific visual depictions of physical and tangible objects produced on a display.

The present invention is not limited to the above embodiments, but can be modified, equivalent, improved, etc. by the same means to achieve the technical effects of the present invention, which are included in the spirit and principle of the present invention. Various modifications and variations are possible in the technical solution and/or in the embodiments within the scope of the invention.

Claims

1. A color filter array, characterized by:

2. The color filter array of claim 2, wherein:

the first row of the basic unit comprises a red filtering channel, a white long exposure channel, a blue filtering channel and a white long exposure channel which are sequentially arranged;

the fourth row of the basic unit comprises a white short exposure channel, a green filtering channel, a white short exposure channel and a green filtering channel which are sequentially arranged.

3. The color filter array of claim 2, wherein:

the exposure time of the white long exposure channel is longer than that of the white short exposure channel, and: the exposure time of the white long exposure channel, the red filter channel, the blue filter channel and the green filter channel is the same, or the exposure time of the white short exposure channel, the red filter channel, the blue filter channel and the green filter channel is the same;

Or alternatively

4. An interpolation method for interpolating a pixel point of an image sensor using the color filter array of any one of claims 1 to 3, the interpolation method comprising:

5. The interpolation method according to claim 4, wherein the performing HDR synthesis on the white pixel points includes:

according to the formula

6. The interpolation method according to claim 5, wherein the obtaining the exposure ratio α of the white long exposure channel with respect to the white short exposure channel includes:

By the formulaOr->Performing calculation to obtain the exposure ratio alpha; wherein T is _L For the exposure of the white long exposure channelBetween T _s Val is the exposure time of the white short exposure channel _L To use the color filter array to shoot the gray scale card with uniform illumination, the value of the white long exposure channel, val _S In order to use the color filter array to shoot the gray scale card with uniform illumination, the value of the white short exposure channel, blc is the black level corresponding to the image sensor using the color filter array.

7. The interpolation method according to claim 4, wherein the performing white interpolation on the red pixel, the blue pixel, and the green pixel includes:

according to the formula

8. The interpolation method according to claim 4, wherein the performing green interpolation on the white pixel point, the red pixel point, and the blue pixel point includes:

for the white short exposure pixel point, according to the formula

else

Determining a green pixel value of the white short exposure pixel point; wherein G is ₃₂ For the green pixel value of the white short-exposure pixel point of the color filter array at a relative position of 32,horizontal gradient corresponding to pixel point with relative position of 32 is represented by +.>Representing the vertical gradient corresponding to a pixel point with a relative position of 32, abs () represents taking the absolute value, W ₂₂ For the white pixel value, W, of the white pixel point of the color filter array at a relative position of 22 ₃₁ For the white pixel value, W, of the white pixel point of the color filter array with a relative position of 31 ₃₃ For the white pixel value, W, of the white pixel point of the color filter array at a relative position of 33 ₄₂ For the white pixel value of the white pixel point with a relative position of 42 in the color filter array, G ₁₁ G is the green pixel value of the green pixel point with the relative position of 11 in the color filter array ₁₃ G is the green pixel value of the green pixel point with the relative position of 13 in the color filter array ₃₁ G is the green pixel value of the green pixel point with the relative position of 31 in the color filter array ₃₃ G, which is the green pixel value of the green pixel point with the relative position of 33 in the color filter array ₅₁ G is the green pixel value of the green pixel point with the relative position of 51 in the color filter array ₅₃ A threshold value is represented by Thr for the green pixel value of the green pixel point of the color filter array with a relative position of 53;

for the white long exposure pixel point, according to the formula

else

Determining a green pixel value of the white long-exposure pixel point; wherein G is ₂₃ Green pixel value for the white long exposure pixel point of relative position 23 in the color filter array Horizontal gradient corresponding to pixel point with relative position 23 is represented by +.>Representing the vertical gradient corresponding to a pixel point with a relative position of 23, abs () represents taking the absolute value, W ₁₃ A white pixel value W for the white pixel point with a relative position of 13 in the color filter array ₂₂ For the white pixel value, W, of the white pixel point of the color filter array at a relative position of 22 ₂₄ For the white pixel value, W, of the white pixel point of the color filter array at a relative position of 24 ₃₃ For the white pixel value of the white pixel point with a relative position of 33 in the color filter array, G ₁₁ G is the green pixel value of the green pixel point with the relative position of 11 in the color filter array ₁₃ G is the green pixel value of the green pixel point with the relative position of 13 in the color filter array ₁₅ G is the green pixel value of the green pixel point with the relative position of 15 in the color filter array ₃₁ G is the green pixel value of the green pixel point with the relative position of 31 in the color filter array ₃₅ G is the green pixel value of the green pixel point with the relative position of 35 in the color filter array ₃₃ A threshold value is represented by Thr for the green pixel value of the green pixel point with a relative position of 33 in the color filter array;

For the red pixel point or the blue pixel point, according to the formula

Grad _A ＝12*W ₂₂ -W ₁₃ -W ₃₁ |+|G ₁₃ -G ₃₁ |

Grad _D ＝|2*W ₂₂ -W ₁₁ -W ₃₃ |+|G ₁₁ -G ₃₃ |

if|Grad _A -Grad _D |＜Thr：

elseif Grad _A ＜Grad _D

else

Determining a green pixel value of the red pixel point or the blue pixel point; wherein G is ₂₂ Grad is the green pixel value of the red pixel point or the blue pixel point with the relative position of 22 in the color filter array _A Represents the horizontal gradient corresponding to the pixel point with the relative position of 22, grad _D Representing the vertical gradient corresponding to the pixel point with the relative position of 22, abs () represents taking the absolute value, W ₁₁ A white pixel value W for the white pixel point with a relative position of 11 in the color filter array ₁₃ A white pixel value W for the white pixel point with a relative position of 13 in the color filter array ₂₂ For the white pixel value, W, of the white pixel point of the color filter array at a relative position of 22 ₃₁ For the white pixel value, W, of the white pixel point of the color filter array with a relative position of 31 ₃₃ For the white pixel value of the white pixel point with a relative position of 33 in the color filter array, G ₁₁ G is the green pixel value of the green pixel point with the relative position of 11 in the color filter array ₁₃ G is the green pixel value of the green pixel point with the relative position of 13 in the color filter array ₁₅ G is the green pixel value of the green pixel point with the relative position of 15 in the color filter array ₃₁ G is the green pixel value of the green pixel point with the relative position of 31 in the color filter array ₃₅ G is the green pixel value of the green pixel point with the relative position of 35 in the color filter array ₃₅ The threshold value is denoted Thr for the green pixel value of the green pixel point of the color filter array with a relative position of 33.

9. The interpolation method according to claim 4, wherein the performing blue interpolation on the white pixel point, the red pixel point, and the green pixel point includes:

for the red pixel point, according to the formula

else

Determining a blue pixel value of the red pixel point; wherein B is ₃₃ For the blue pixel value of the red pixel point of the color filter array at a relative position of 33,image representing relative position 33The horizontal gradient corresponding to the pixel point,representing the vertical gradient corresponding to the pixel point with the relative position of 33, abs () represents taking the absolute value, W ₁₃ A white pixel value W for the white pixel point with a relative position of 13 in the color filter array ₂₃ For the white pixel value, W, of the white pixel point of the color filter array at a relative position of 23 ₃₁ For the white pixel value, W, of the white pixel point of the color filter array with a relative position of 31 ₃₂ A white pixel value W for the white pixel point with a relative position of 32 in the color filter array ₃₃ For the white pixel value, W, of the white pixel point of the color filter array at a relative position of 33 ₃₄ For the white pixel value, W, of the white pixel point of the color filter array at a relative position of 34 ₃₅ A white pixel value W for the white pixel point with a relative position of 35 in the color filter array ₄₃ A white pixel value W for the white pixel point with a relative position 43 in the color filter array ₅₃ B is the white pixel value of the white pixel point with the relative position of 53 in the color filter array ₁₃ B, the blue pixel value of the blue pixel point with the relative position of 13 in the color filter array ₃₁ B, as the blue pixel value of the blue pixel point with the relative position of 31 in the color filter array ₃₅ B, the blue pixel value of the blue pixel point with the relative position of 35 in the color filter array ₅₃ For the blue pixel value of the blue pixel point with a relative position of 53 in the color filter array, thr represents a threshold value;

For the green pixel point, according to the formula

Determining a blue pixel value of the green pixel point; wherein B is ₂₂ B is the blue pixel value of the green pixel point with the relative position of 22 in the color filter array ₂₄ B is the blue pixel value of the green pixel point with the relative position of 24 in the color filter array ₄₂ B is the blue pixel value of the green pixel point with the relative position of 42 in the color filter array ₄₄ Blue pixel value, W, for the green pixel point of the color filter array at a relative position 44 ₁₁ A white pixel value W for the white pixel point with a relative position of 11 in the color filter array ₁₅ A white pixel value W for the white pixel point with a relative position of 15 in the color filter array ₂₂ For the white pixel value, W, of the white pixel point of the color filter array at a relative position of 22 ₂₄ For the white pixel value, W, of the white pixel point of the color filter array at a relative position of 24 ₃₃ For the white pixel value, W, of the white pixel point of the color filter array at a relative position of 33 ₄₂ A white pixel value W for the white pixel point of the color filter array with a relative position 42 ₄₄ A white pixel value W for the white pixel point with a relative position 44 in the color filter array ₅₁ A white pixel value W for the white pixel point with a relative position of 51 in the color filter array ₅₅ B is the white pixel value of the white pixel point with the relative position of 55 in the color filter array ₁₁ For a relative position of 11 in the color filter arrayBlue pixel value of the blue pixel point of (B) ₁₅ B, as the blue pixel value of the blue pixel point with the relative position of 15 in the color filter array ₃₃ B is the blue pixel value of the blue pixel point with the relative position of 33 in the color filter array ₅₁ B is the blue pixel value of the blue pixel point with the relative position of 51 in the color filter array ₅₅ A threshold value is represented by Thr for the blue pixel value of the blue pixel point with a relative position of 55 in the color filter array;

for the white pixel point, according to the formula

else

10. The interpolation method according to any one of claims 4 to 9, characterized in that the interpolation method further comprises:

by the formulaCalculating a gain value gain;

according to the formula

Calculating a corrected red pixel valueCorrecting the green pixel value +. >And correcting the blue pixel value +.>