CN104867453B - The dot structure conversion method and its device of display screen - Google Patents

Abstract

The invention discloses a pixel structure conversion method of a display screen and a device thereof. The pixel structure conversion method comprises the following steps: taking out the three-primary-color grayscales of all pixel units in the image of the input RGB form; taking out the three-primary-color grayscales of three to five adjacent pixel units in the original image one by one, and converting them into new grayscales , so that the grayscale square difference between the original pixel unit and the new pixel unit is minimized; and after all new grayscales are obtained, the input image is redisplayed in the form of RGBG. In this way, the existing RGB display is converted to RGBG display, and the mismatch problem of the pixel structure is solved.

Description

Pixel structure conversion method and device for display screen

technical field

The invention relates to the display field, in particular to a pixel structure conversion technology of a display screen.

Background technique

Compared with other display screens (such as LCD, etc.), AMOLED (active matrix organic light-emitting diode, English: Active-matrix organic light-emitting diode) screen has many advantages, including a full range of 180-degree viewing angle, fast response speed, and easy ultra-thin design. AMOLED display technology has received extensive attention in the world, and large international companies represented by Samsung, LG, Sharp, and AU Optronics are actively developing this technology. Currently, AMOLED displays are mainly used in mobile phones and portable media players. According to data analysis provided by ABI, shipments of smartphones priced below US$200 will grow to approximately 238 million units in 2013, and this number will surge to 758 million units in 2018. Displaysearch data shows that in recent years, driven by the rapid growth of the smart phone market, the proportion of AMOLED panels used in the global mobile phone field to total shipments has risen rapidly, and by 2016, the proportion will exceed 70%. According to displaysearch data, by 2016, global AMOLED panel shipments will reach 395 million pieces, of which about 283 million pieces will be used in mobile phones. At present, in the field of high-end electronic products, AMOLED displays have gradually become one of the important differentiating factors between products. In addition to the promotion of the smartphone market, with the further maturity of technology in the future, the yield rate will gradually increase, the production cost will be greatly reduced, and the shortcomings of high product prices will be gradually alleviated. In addition, large-size panels will also be mass-produced gradually in the future, and the application of AMOLED panels in notebook computers, netbooks, monitors, and TVs will gradually increase. According to displaysearch data, it is expected that by 2016, it will grow substantially to US$7.1 billion, with a compound annual growth rate of 36%.

Figure 2 shows two AMOLED pixel structures, the pixel structure shown in Figure 2(a) is RGBW, and the pixel structure shown in Figure 2(b) is RGBG, where the green sub-pixels are alternately arranged in the red and blue sub-pixels between pixels.

As shown in Figure 2(b), for RGBG screens, each pixel consists of two sub-pixels: RG or BG. As we all know, in order to be able to display all the colors in the CIE chromaticity diagram, each pixel should contain three primary color sub-pixels RGB. Therefore, to display all colors in a pixel unit containing only two sub-pixels, it is necessary to use the method of pixel borrowing. For example, in an RGBG pixel structure, a pixel unit composed of RG needs to borrow a missing B sub-pixel from an adjacent pixel unit to form the three primary colors of RGB. Compared with the conventional RGB strip pixel structure, for the same resolution, the number of sub-pixels required by the RGBG screen is one-third less than that required by the RGB strip structure, which greatly reduces the cost. In addition, for a screen of the same physical size, the resolution that an RGBG screen can achieve is 1.5 times that of a conventional strip RGB. Finally, for the same physical size and the same resolution, the sub-pixel area of the RGBG screen can be made larger. When displaying the same brightness, the required current is smaller, which is beneficial to slow down the aging of AMOLED.

To sum up, most images are arranged in RGB stripes. In order to display images on an RGBG screen, there is an urgent need in this field for a pixel structure conversion method for converting RGB display to RGBG display.

Contents of the invention

The object of the present invention is to provide a pixel structure conversion method and device for a display screen, which converts the existing RGB display to RGBG display based on the square difference of gray levels, and solves the problem of pixel structure mismatch.

In order to solve the above-mentioned technical problems, the embodiment of the present invention discloses a pixel structure conversion method of a display screen, the method includes the following steps:

Take out the three primary color grayscales of all pixel units in the input RGB image;

Take out the three primary color gray scales of the adjacent three to five pixel units of the input image one by one, and convert them into new gray scales, so that the gray scale square difference between the original pixel unit and the new pixel unit is the smallest; and

After all the new grayscales are obtained, the input image is redisplayed in RGBG.

The embodiment of the present invention also discloses a pixel structure conversion device of a display screen, comprising:

a grayscale acquisition unit, configured to retrieve the grayscales of the three primary colors of all pixel units in the input image in the form of RGB;

The grayscale conversion unit is used to take out the three-primary-color grayscales of the input adjacent three to five pixel units one by one, and convert them into new grayscales, so that the grayscale square difference between the original pixel unit and the new pixel unit is the smallest; and

The display unit is used to re-display the input image in the form of RGBG after obtaining all the new gray scales.

Compared with the prior art, the embodiment of the present invention has the main difference and its effects in that:

By regenerating a new gray scale for the gray scale of the corresponding pixel unit of the original image, the gray scale square difference between the original pixel unit (RGB format original image) and the new pixel unit (RGBG format) can be minimized, which can weaken RGBG Color fringing effect for format images.

Further, converting to a new gray scale includes the following steps: constructing a function in which the gray scale square difference varies with the gray scale of the red and blue channels in the display screen, and solving the corresponding gray scale when the gray scale square error is the smallest, while maintaining The gray scale of green in the display screen remains unchanged, thus, the display effect produced by the obtained new gray scale is better.

Further, the display screen is an AMOLED screen, although the present invention is applicable to all display screens with an RGBG pixel structure, and is not limited to an AMOLED screen.

Description of drawings

FIG. 1 is a schematic flowchart of a pixel structure conversion method in the first embodiment of the present invention.

FIG. 2 is a schematic diagram of pixel structures of two types of display screens.

Fig. 3 is a schematic diagram of pixel structure conversion from RGB to RGBG.

FIG. 4 is a schematic diagram of determining the gray scale square difference in the pixel structure conversion method in FIG. 1 .

FIG. 5 is a schematic structural diagram of a pixel structure conversion device in the second embodiment of the present invention.

Detailed ways

In the following description, many technical details are proposed in order to enable readers to better understand the application. However, those skilled in the art can understand that without these technical details and various changes and modifications based on the following implementation modes, the technical solution claimed in each claim of the present application can be realized.

First, before introducing the content of the invention in detail, some basic knowledge about pixel structure conversion in the present invention will be introduced.

Through direct mapping, the grayscale original value of each sub-pixel in the original image can be directly assigned to the sub-pixel at the corresponding position in the RGBG screen. As shown in Figure 3, R _2i and G _2i of pixel 1 in the original image are respectively assigned to R _2i ' and G _2i ' of pixel 1' in the RGBG screen, and B _2i+1 and G _2i of pixel 2 in the original image are assigned ₊₁ is respectively assigned to B _2i+1 ' and G _2i+1 ' of pixel 2' in the RGBG screen.

A schematic diagram of pixel structure conversion from RGB to RGBG is shown in Figure 3. Figure 3(a) shows 4 continuous pixel units in an RGB format image, and Figure 3(b) shows 4 continuous pixel units at corresponding positions in an RGBG screen. The pixel structure conversion from RGB to RGBG is based on the gray scale of each pixel unit known in the original image, and the gray scale of the pixel unit at the corresponding position in the RGBG screen is obtained. Since the smallest repeating unit of the RGBG screen occupies 2 pixels, the number of pixels is set to 2i, 2i+1, where i=0,1,2,...,N/2-1, N is the total number of pixels in the image number. In FIG. 3( a ), pixel 1 and pixel 2 inside the big dotted line box correspond to pixel 1 ′ and pixel 2 ′ inside the big dotted line box in FIG. 3( b ), respectively.

From the perspective of data processing, it is necessary to first store the gray scale of each pixel unit in the original image in the memory, and then read it out pixel by pixel, process it according to a specific conversion method, and convert the processed gray scale pixel by pixel. stored in another storage area of the memory.

As we all know, in the CIE (International Commission on Illumination) chromaticity diagram, all colors can be expressed by the combination of red, green and blue primary colors. However, in an RGBG screen, each pixel unit contains only 2 sub-pixels, that is, only 2 primary colors. Therefore, each pixel unit in the RGBG screen needs to borrow the missing sub-pixel from the adjacent pixel unit to display all colors. As shown in Figure 3(b), a pixel unit in an RGBG screen includes 2 sub-pixels, RG or BG. As mentioned above, in order to be able to display all colors in the CIE chromaticity diagram, a pixel unit should contain three primary color sub-pixels. Since each pixel unit of the RGBG screen consists of two sub-pixels (RG or BG), the missing sub-pixel needs to be borrowed from adjacent pixels.

As shown in Figure 3(b), the two sub-pixels of pixel 1' are R _2i ' and G _2i ', and this pixel unit lacks blue sub-pixels, so B _2i+ is borrowed from the adjacent pixel 2' ₁ ', to form a complete three-primary color.

The following briefly introduces the visual effect evaluation indicators displayed by RGBG images.

Figure 3(a) is the original image in RGB format, and Figure 3(b) is the corresponding RGBG. Taking pixel 1 as an example, pixel 1 in the original image corresponds to 1' in RGBG. This pixel unit only contains 2 sub-pixels (R2i' and G2i'), and the nearest blue sub-pixel needs to be borrowed from adjacent pixels. pixel, B _2i+1 ' in pixel 2' is borrowed here, and these three sub-pixels constitute a pixel 1", which is called a virtual pixel of pixel 1'.

Raw Pixels:

Pixel 1 (R _2i ,G _2i ,B _2i )

Pixel 2 (R _2i+1 ,G _2i+1 ,B _2i+1 )

Virtual Pixels:

Pixel 1" (R _2i ', G _2i ', B _2i+1 '), where B _2i+1 ' is borrowed from pixel 2'.

Pixel 2"(R _2i+2 ', G _2i+1 ', B _2i+1 '), where R _2i+2 ' is borrowed from pixel 3'.

An image composed of all virtual pixels is a virtual image. A virtual pixel is formed by sub-pixels in RGBG through the principle of pixel borrowing. Since the grayscale of the three primary colors of the virtual pixel determines the color and brightness of the corresponding pixel unit, the quality of the virtual image can reflect whether the conversion is superior. For the same image, the number of sub-pixels used by the RGBG type panel is reduced by one third compared with the number of sub-pixels of the original image. Since the display in this format uses fewer sub-pixels to display the same image, the visual effect displayed on the image screen will be more or less reduced. It is necessary to evaluate the visual effect of the image displayed on the RGBG screen. As shown in FIG. 3 , the color and brightness of pixel 1 and pixel 2 are respectively determined by the gray scale of their respective pixels. Correspondingly, the color and brightness of the pixel 1' and the pixel 2' are respectively determined by the gray scale of their respective virtual pixels. Therefore, the difference between the original pixel unit and the virtual pixel unit should be used to evaluate the visual effect of the image displayed on the RGBG screen.

(1) Square difference of gray scale

Grayscale square difference is a common visual effect evaluation index, as shown in Figure 4, the upper part of Figure 4 is the 4 pixels in the RGB format image, and the lower part is the 4 pixels in the corresponding position in the RGBG screen . Since the smallest repeating unit of the RGBG screen occupies 2 pixels, the subscript of the pixel is 2i, 2i+1, where i=0,1,2,...,N/2-1, N is the total number of pixels of the image number. For the red channel, the grayscale squared difference is:

Among them, N is the total number of pixels in the image, R' _2i and R' _2i+2 are the unknowns to be solved, F _R is a function that changes with R' _2i and R' _2i+2 , R _2i , R _{2i+ 1} is the gray scale of the original image, which is known. It can be seen from FIG. 4 that the sub-pixel R _{2i of the image corresponds to the sub-pixel R' 2i of} the display screen in one-to-one spatial position, so the two are compared. However, for the sub-pixel R _2i+1 of the image, there is no spatially corresponding sub-pixel in the display screen. Here, in order to take into account the influence of the left and right adjacent pixels (R′ _2i and R′ _2i+2 ), the average value of the two Compare with subpixel R _2i+1 of the image. From this, the expression of the square difference of the gray scale of the red channel can be obtained.

In the same way, the expression of the square difference of the gray scale of the blue channel can be obtained:

(2) Color edge effect

Due to the influence of the color edge effect, the visual effect of the image displayed on the RGBG AMOLED screen will be degraded. Therefore, during the conversion process from RGB to RGBG, this effect should be minimized as much as possible. The color fringing effect in the RGBG screen is shown in Figure 3. As a special example, for the high-frequency components in the original image (the gray scale difference between adjacent pixels is large), the gray scale of the original image is:

0(0,0,0),1(255,255,255),2(255,255,255),3(0,0,0),

If the gray scale of RGBG is obtained by direct assignment, then

B _i-1 '=B _i-1 =0, G _i-1 '=G _i-1 =0

R _i '=R _i =255, G _i '=G _i =255

B _i+1 '=B _i+1 =255, G _i+1 '=G _i+1 =255

R _i+2 '=R _i+2 =0, G _i+2 '=G _i+2 =0.

The gray scale of the virtual pixel is: 0”(255,0,0), 1”(255,255,255), 2”(0,255,255). In the original image, the color of pixel 0 is black, but after conversion, the corresponding pixel becomes red , the color distortion is very large. For some high-frequency image information, the converted color is different from the original color. This phenomenon is called the color edge effect.

To evaluate the color edge effect, first convert the original image to YUV space, where U, V represent color-related information, get U, V histogram, then convert the virtual image to YUV space, get the histogram, and then Comparing the difference between the original image and the virtual image histogram, as an example of evaluation, the following formula is given:

PSNR _U ＝10×log ₁₀ (255 ² /MSE _U )

Among them, Ui and Ui' represent the U component of the original image and the virtual image respectively, and N is the total number of pixels of the image. Define PSNR _V in a similar way. The larger the PSNR _U , the smaller the difference between the original image and the virtual image, so the display effect on RGBG is better.

In order to make the purpose, technical solution and advantages of the present invention clearer, the following will further describe the implementation of the present invention in detail in conjunction with the accompanying drawings.

The first embodiment of the present invention relates to a pixel structure conversion method of a display screen. FIG. 1 is a schematic flowchart of the pixel structure conversion method.

Specifically, as shown in Figure 1, the pixel structure conversion method includes the following steps:

In step S101, the three-primary-color grayscales of all pixel units in the input image in RGB format are taken out.

Specifically, for the input image, the three primary color gray scales of all pixel units in the image are taken out and stored.

Then enter step S102, take out the gray scales of the three primary colors of three to five adjacent pixel units in the original image one by one, and convert them into new gray scales, so that the gray scale square difference between the original pixel unit and the new pixel unit is the smallest.

Specifically, the three-primary-color grayscales of adjacent three to five pixel units in the image are taken out one by one. The expression of the new grayscale of these pixel units is set so that the square difference of the grayscale between the original pixel unit (RGB format original image) and the new pixel unit (RGBG format) is minimized. Preferably, the three-primary-color gray scales of four adjacent pixel units can be taken out, at this time, the amount of calculation is small and the display accuracy is high.

In the image to be displayed and the display screen, there is a one-to-one correspondence between the sub-pixels of the green channel, so the algorithm does not change the gray scale of the green channel. However, for the red and blue channels, the number of subpixels in the display is half the number of subpixels in the image. Therefore, it is no longer possible to obtain new sub-pixel gray scales through direct assignment. For the grayscale of the red channel and blue channel of the display, the grayscale of the red and blue channels in the display can be set as unknowns, and the function of the grayscale square difference changing with these unknowns can be constructed, and then the grayscale square error can be solved The grayscale corresponding to the minimum hour.

make Where k=0,1,...,N/2-1, N/2 N/2-element linear equations are obtained, and this equation system has a unique solution.

Here, the red channel is taken as an example for illustration. The grayscale squared difference of the red channel is

Next, find the expression of the partial derivative. Since among all the summation terms of the function FR, two terms appear _R ' _2k

(1) When i=k, item, appears R' _2k

(2) When i=k-1, item,

that is R _2k also occurs, so,

Among them, k=0,1,...,N/2-1

Written in matrix form:

Solving this matrix equation, we get:

For the blue channel, the same can be obtained

After the new gray scale value is determined, the conversion from RGB to RGBG can be performed.

Then enter step S103, after obtaining all the new gray scales, redisplay the input image in RGBG mode.

Specifically, for each pixel unit taken out, the gray levels R _2i ', G _2i ' and B _2i+1 ', G _2i+1 ' of the pixel unit at the corresponding position in the RGBG screen are obtained and stored, and then according to the RGBG type The image display driving sequence of the AMOLED screen transmits the new image gray scales R _2i ', G _2i ', B _2i+1 ', and G _2i+1 ' obtained from the above conversion to the screen end,

Thereafter, this process ends.

Effect

In order to evaluate the color fringing effect objectively, compare PSNR _U and PSNR _V for different images, as shown in Table 1 and Table 2.

As can be seen from Table 1 and Table 2, the PSNR value of the image processed by the present invention is always greater than the PSNR value of the image processed by the prior art, indicating that the present invention greatly improves the color fringe effect.

Table 1 PSNR _U comparison of three different images

image current technology this invention (a) 32.79 32.93 (b) 29.30 30.67 (c) 31.83 32.54

Table 2 PSNR _V comparison of three different images

image current technology this invention (a) 32.20 32.15 (b) 30.25 31.34 (c) 32.26 32.80

In order to evaluate the difference between the original image and the processed image, it is necessary to compare FB and FR, and take the average value of all pixel units, which are MFB and MFR, respectively.

Table 3 MFB comparison of three images

image current technology this invention (a) 54.96 47.11 (b) 157.89 115.92

(c) 49.89 44.84

Table 4 MFR comparison of three images

image current technology this invention (a) 58.41 51.49 (b) 141.52 103.84 (c) 50.39 45.31

For the same three images, the MFB and MFR values of the images processed by the pixel conversion algorithm are shown in Tables 3 and 4. The value of the image processed by the present invention is always smaller than the processing result of the prior art. After processing a large number of other images and analyzing the results, it can also be seen that the pixel conversion method of the present invention is superior to the prior art.

In the above description of the present invention, although an AMOLED screen is taken as an example, the present invention is actually applicable to all display screens with RGBG pixel structures, and is not limited to AMOLED screens. That is to say, the above-mentioned pixel structure conversion method of the present invention can be applied to all display screens with BGRG pixel structure through simple replacement, not limited to AMOLED screens.

All method implementations of the present invention can be implemented in software, hardware, firmware and other ways. Regardless of whether the invention is implemented in software, hardware, or firmware, the instruction codes may be stored in any type of computer-accessible memory (e.g., permanent or modifiable, volatile or nonvolatile, solid-state or non-solid state, fixed or replaceable media, etc.). Similarly, the memory can be, for example, Programmable Array Logic (Programmable Array Logic, referred to as "PAL"), Random Access Memory (Random Access Memory, referred to as "RAM"), Programmable Read Only Memory (Programmable Read Only Memory, referred to as "PROM") ), Read-Only Memory (Read-Only Memory, referred to as "ROM"), Electrically Erasable Programmable Read-Only Memory (Electrically Erasable Programmable ROM, referred to as "EEPROM"), magnetic disk, optical disc, Digital Versatile Disc (Digital Versatile Disc, referred to as "DVD") and so on.

The second embodiment of the present invention relates to a pixel structure converting device of a display screen. FIG. 5 is a schematic structural diagram of the pixel structure conversion device. The actual structure of the present invention can make necessary adjustments according to actual needs, and is not limited to the structure in FIG. 5 .

Specifically, the pixel structure conversion device performs pixel conversion to solve the problem of pixel structure mismatch. As shown in FIG. 5, the pixel structure conversion device 100 includes:

A gray scale acquiring unit 101, configured to extract the gray scales of the three primary colors of all pixel units in the input image in the form of RGB;

The gray scale conversion unit 102 is used to take out the three primary color gray scales of three to five adjacent pixel units in the original image one by one, and convert them into new gray scales, so that the gray scale square difference between the original pixel unit and the new pixel unit is the smallest; as well as

The display unit 103 is configured to re-display the input image in the form of RGBG after all new gray scales are obtained.

The first embodiment is a method implementation corresponding to this embodiment, and this embodiment can be implemented in cooperation with the first embodiment. The relevant technical details mentioned in the first embodiment are still valid in this embodiment, and will not be repeated here to reduce repetition. Correspondingly, the relevant technical details mentioned in this implementation manner can also be applied in the first implementation manner.

It should be noted that each unit mentioned in each device embodiment of the present invention is a logical unit. Physically, a logical unit may be a physical unit, or a part of a physical unit, or may be a plurality of physical units. The combination of units, the physical implementation of these logic units is not the most important, the combination of functions realized by these logic units is the key to solve the technical problems raised by the present invention. In addition, in order to highlight the innovative part of the present invention, the above-mentioned equipment implementations of the present invention do not introduce units that are not closely related to solving the technical problems proposed by the present invention. unit.

It should be noted that in the claims and description of this patent, relative terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or Any such actual relationship or order between such entities or operations is implied. Furthermore, the term "comprises", "comprises" or any other variation thereof is intended to cover a non-exclusive inclusion such that a process, method, article, or apparatus comprising a set of elements includes not only those elements, but also includes elements not expressly listed. other elements of or also include elements inherent in such a process, method, article, or apparatus. Without further limitations, an element defined by the statement "comprising a" does not exclude the presence of additional identical elements in the process, method, article or apparatus comprising said element.

Although the present invention has been illustrated and described with reference to certain preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the present invention. The spirit and scope of the invention.

Claims (6)

1. a pixel structure conversion method of display screen, is characterized in that, comprises the following steps: Take out the three primary color grayscales of all pixel units in the input RGB image; Take out the three-primary-color grayscales of the adjacent three to five pixel units of the input image one by one, and convert them into new grayscales, so that the grayscale square difference between the original pixel unit and the new pixel unit is the smallest, The conversion to a new gray scale includes the following steps: For the two channels of red and blue, construct the function that the square difference of gray scale varies with the gray scale of the red and blue channels in the display screen, and solve the corresponding The gray level; at the same time for the green channel, the new gray level is equal to the gray level of the original image, Among them, for the red channel, the grayscale square difference is: Among them, N is the total number of pixels in the image, R' _2i and R' _2i+2 are the unknowns to be solved, F _R is a function that changes with R' _2i and R' _2i+2 , R _2i , R _{2i+ 1} is the gray scale of the original image; For the blue channel, the expression for the squared difference of gray levels is: N is the total number of pixels in the image, B' _2i-1 and B' _2i+1 are the unknowns to be solved, F _B is a function that changes with B' _2i-1 and B' _2i+1 , B _2i and B _2i+1 is the gray scale of the original image; and After obtaining all the new gray scales, re-display the input image in the form of RGBG; where, The matrix form of the gray scale square difference of the red channel is: The matrix form of the gray scale square difference of the blue channel is: in, 2. pixel structure conversion method as claimed in claim 1, is characterized in that, The display screen is an AMOLED screen. 3. pixel structure conversion method as claimed in claim 1, is characterized in that, When the three-primary-color grayscales of three to five adjacent pixel units of the input image are taken out one by one, the three-primary-color grayscales of four pixel units are taken out. 4. A pixel structure conversion device for a display screen, characterized in that it comprises: a grayscale acquisition unit, configured to retrieve the grayscales of the three primary colors of all pixel units in the input image in the form of RGB; The gray scale conversion unit is used to take out the three primary color gray scales of the adjacent three to five pixel units of the input image one by one, and convert them into new gray scales, so that the gray scale square difference between the original pixel unit and the new pixel unit is the smallest , where converting to a new gray scale includes the following steps: For the red and blue channels, construct a function that the gray scale square difference varies with the gray scale of the red and blue channels in the display, and solve the gray scale square difference when it is the smallest The corresponding grayscale; meanwhile, for the green channel, the new grayscale is equal to the grayscale of the original image, Among them, for the red channel, the grayscale square difference is: Among them, N is the total number of pixels in the image, R' _2i and R' _2i+2 are the unknowns to be solved, F _R is a function that changes with R' _2i and R' _2i+2 , R _2i , R _{2i+ 1} is the gray scale of the original image; For the blue channel, the expression for the squared difference of gray levels is: N is the total number of pixels in the image, B' _2i-1 and B' _2i+1 are the unknowns to be solved, F _B is a function that changes with B' _2i-1 and B' _2i+1 , B _2i and B _2i+1 is the gray scale of the original image, where, The matrix form of the gray scale square difference of the red channel is: The matrix form of the gray scale square difference of the blue channel is: in, as well as The display unit is used to re-display the input image in the form of RGBG after obtaining all the new gray scales. 5. The pixel structure conversion device as claimed in claim 4, characterized in that, The display screen is an AMOLED screen. 6. The pixel structure converting device according to claim 4, characterized in that, When the three-primary-color grayscales of three to five adjacent pixel units of the input image are taken out one by one, the three-primary-color grayscales of four pixel units are taken out.