CN111261077A - Color difference analysis method and display with color difference analysis function - Google Patents
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Abstract
The invention discloses a chromatic aberration analysis method, which comprises the following steps: 1. constructing a color set with the number of colors being not less than 20, wherein the color set comprises 100% white, 100% red, 100% green, 100% blue, 100% cyan, 100% magenta and 100% yellow; 2. measuring a color block displayed by a display to obtain a CIEXYZ measurement value; 3. converting the CIEXYZ measurement values of 7 colors in the CIEXYZ measurement values in the step 2 to obtain CIEYxy measurement values, and taking an x component and a y component in the CIEYxy measurement values as chromaticity coordinates of the 7 colors in a CIExy coordinate system; 4. converting all RGB color values in the color set into CIEXYZ reference values; 5. converting the CIEXYZ measured value and the CIEXYZ reference value into a CIELab measured value and a CIELab reference value respectively; 6. the color difference between the CIELab measurement and the CIELab reference is calculated. The invention also provides a display with a color difference analysis function, and the color of the display can be intuitively and efficiently evaluated only by externally connecting a colorimeter, so that the color difference can be calculated more accurately, and the evaluation result is more objective and real.
Description
Technical Field
The invention belongs to the field of video display, and particularly relates to a chromatic aberration analysis method and a display with a chromatic aberration analysis function.
Background
In the broadcast and television industries, it is necessary to ensure that the color of the display is substantially consistent during the video production process as much as possible, for example, in the high definition video production, it is necessary to ensure that the color gamut of the display is rec.709. It is generally necessary to evaluate the color of all displays and then color correct for displays that are color inaccurate, or to directly replace the display.
The color of a display is generally evaluated by several methods:
comparison and observation method: the method is characterized in that a display with an absolute standard is found as a reference, then various test signals are simultaneously input to the display, and an observer judges whether the color of the display to be tested meets the standard or not through naked eye comparison, so that the method is a qualitative evaluation mode.
Automatic evaluation method of PC software: the method comprises the steps of driving a colorimeter or a photometer to sample colors of a display through third-party color management software such as Calman, driving the display to generate corresponding color fields through an HDMI or USB protocol, recording the corresponding chromaticity and brightness value of each color field, automatically generating a detailed report after a user measures each display, and judging whether the colors of the display to be measured meet the standard or not through the report, wherein the report is a quantitative evaluation mode.
The contrast observation method has the disadvantages of being too subjective, slightly different in color impression of each observer, and causing visual fatigue of the observer after long-time observation, so that the observer cannot continue to observe. The automatic evaluation method of the PC software has the problems of complex operation, generally requiring original factory engineers to operate, difficulty in one-to-one correspondence between the generated report file and each display, and requirement of users for additional PC equipment and professional color management software.
If the publication number is CN106409265B, the publication date is 2019, 3, 29, and the chinese patent named as a method for adjusting color difference of a display discloses a technical solution, by obtaining color coordinates of a plurality of reference points, and a plurality of reference RGB voltage values corresponding to the reference points under a plurality of brightness values, the RGB voltage values include three voltage components corresponding to red, green, and blue, respectively; obtaining an actual RGB value according to an actual color coordinate and an actual brightness value of a point to be regulated; setting a target color coordinate and a target brightness value, and obtaining a target RGB value according to the target color coordinate and the brightness value; selecting a reference RGB voltage value corresponding to a reference point closest to the target color coordinate and the target brightness value; and adjusting the actual RGB value by taking the selected reference RGB voltage value as a reference and the target RGB value as a target. The method for adjusting the color difference of the display can improve the adjustment efficiency. The patent has the defects that RGB is converted into an XYZ color space, and then subsequent calculation is carried out, the XYZ color space is a non-uniform color space, and the color difference with the real feeling of human eyes exists, so that the color difference is not objective and real.
The application publication number is CN110324476A, the publication date is 2019, 10, 11 and the name of the Chinese patent is a representation method of the color generation performance of the mobile phone screen, and another technical scheme is disclosed, wherein a plurality of red, green and blue primary colors, white field colors and the like are selected as representative colors of the color generation of the mobile phone screen, and the mathematical relationship from RGB of the color generation of the mobile phone screen to CIEXYZ chromaticity is established; and solving three primary color CIExy chromatic values, a CIExy color gamut diagram and a CIE three-dimensional color appearance color gamut diagram of the color generated by the mobile phone according to the representative color chromaticity and the mathematical relationship. Extracting at least five groups of RGB color values of typical memory color and medium gray, testing the color generation chroma and color appearance value, drawing a color appearance value curve which changes along with the RGB color sequence number, and solving the quality parameter. The color generation performance of the mobile phone screen is represented by three primary colors CIExy chromaticity, a CIExy two-dimensional color gamut diagram, a CIE three-dimensional color appearance color gamut diagram, a memory color and medium gray color appearance value curve and quality parameters. The problem that this patent exists lies in through sending the picture to the cell-phone, after the manual measurement, the current software tools such as "color _ science" of rethread calculate and visual show, just need to spend a large amount of time and personnel to the measurement of a cell-phone, is unfavorable for industrialization and automation.
Aiming at the problems that the color evaluation of the display is not objective and real enough and the color evaluation of the display is not automatic and efficient enough in the prior art, an effective solution is needed to be provided.
Disclosure of Invention
1. Problems to be solved
The invention provides a color difference analysis method and a display with a color difference analysis function, aiming at the problem that the color evaluation of the display in the prior art is not objective, real and accurate.
2. Technical scheme
In order to solve the problems, the technical scheme adopted by the invention is as follows: a method of color difference analysis comprising the steps of:
s1, constructing color sets with the number of colors not less than 20, wherein the color sets comprise 100% white, 100% red, 100% green, 100% blue, 100% cyan, 100% magenta and 100% yellow;
s2, measuring color blocks of all colors in the color set displayed by the display to obtain CIEXYZ measurement values of all colors in the color set;
s3, taking the CIEXYZ measured values of 7 colors of 100% white, 100% red, 100% green, 100% blue, 100% cyan, 100% magenta and 100% yellow in the CIEXYZ measured values in the step S2, carrying out color space conversion to obtain CIEYxy measured values, and taking the x component and the y component in the CIEYxy measured values as chromaticity coordinates of the 7 colors in a CIExy coordinate system;
s4, converting the RGB color values of all colors in the color set into CIEXYZ reference values;
s5, converting the CIEXYZ measured values and CIEXYZ reference values of all colors in the color set into CIELab measured values and CIELab reference values through a color space respectively;
and S6, calculating the color difference between the CIELab measured value and the CIELab reference value of all the colors in the color set.
By adopting the technical scheme, the color is converted by adopting the CIELab uniform color space, so that the color difference calculation is more accurate, and the color evaluation result of the display is more objective and real.
Further, the chromaticity coordinates of the 7 colors in step S3 and the color difference in step S6 are displayed in the form of OSD.
The result of the color difference analysis can be displayed more intuitively in an OSD mode, and the color of the display can be evaluated intuitively and efficiently.
Further, the color set in step S1 further includes sky blue, skin color, and grass cyan. Sky blue, skin color and grass cyan are typical colors commonly seen in the display, and the common colors are added in the color set, so that a user can judge whether the display needs to be corrected.
Further, the three color components of the CIEYxy measurement value obtained after the color space conversion in step S3 are [ Lv, X, Y ], Lv ═ Y, X ═ X/(X + Y + Z), Y ═ Y/(X + Y + Z), where [ X, Y, Z ] are the three color components of the CIEXYZ measurement value, respectively.
Further, the CIEXYZ reference value in step S4 is obtained by calculating all RGB color values in the color set with a reference color temperature D65, a reference color gamut rec.709, and a reference gamma of 2.2.
Further, the color difference in step S6 is calculated by using the standard of Delta E2000.
The invention also provides a display with a chromatic aberration analysis function, which comprises a FLASH storage unit, a PS module, a PL module and a liquid crystal display panel; the PS module is in communication connection with the PL module, the colorimeter and the FLASH storage unit respectively, the PL module is in communication connection with the liquid crystal display panel, the PS module reads RGB chromaticity data with concentrated colors from the FLASH storage unit and transmits the RGB chromaticity data to the PL module, and the PS module controls the PL module to display color blocks with concentrated colors on the liquid crystal display panel; the PS module drives the colorimeter to measure color blocks on the liquid crystal display panel, data obtained by measurement of the colorimeter are stored in the FLASH storage unit, and after the PS module performs color difference analysis on the measured data, the PL module is controlled to display a color difference analysis result on the liquid crystal display panel in an OSD mode. By adopting the technical scheme, the color characteristics of the display including three primary colors, color gamut and color difference can be automatically analyzed by the display without a computer, so that the cost is reduced, and the color difference analysis result is displayed on the liquid crystal display panel in an OSD mode, so that the method is more visual.
Further, the colorimeter and the PS module are in communication connection through a USB interface.
Furthermore, the PS module and the PL module realize communication through an AXI bus and register reading and writing.
Further, the OSD displaying includes: CIExy color gamut map, color difference histogram, average color difference value.
3. Advantageous effects
Compared with the prior art, the invention has the beneficial effects that:
(1) the invention can automatically analyze the color characteristics of the display including three primary colors, color gamut and color difference through the display without a computer, thereby being beneficial to reducing the cost;
(2) according to the invention, the nonuniform color space CIEXYZ is converted into the uniform color space CIELab, so that the color difference calculation is more accurate, and the color evaluation of the display is more objective and real;
(3) the invention can simply and objectively display a color difference analysis result on the screen of the display in the form of OSD without the on-site assistance of the original factory engineer of the display, thereby effectively saving the labor cost.
Drawings
FIG. 1 is a block diagram of the present invention;
FIG. 2 is a flow chart of a method of color difference analysis in the present invention;
FIG. 3 is a schematic diagram of an OSD pattern of a color difference analysis result according to the present invention;
FIG. 4 is a schematic diagram of a color set according to the present invention;
FIG. 5 is a schematic view of the connection of a display and colorimeter of the present invention;
in the figure: 11: a FLASH storage unit; 12: a PS module; 13: a USB interface; 14: a PL module; 15: a liquid crystal display panel; 16: a colorimeter.
Detailed Description
The invention is further described with reference to specific examples.
As shown in fig. 1 and 5, the present invention provides a color difference analysis method and a display with a color difference analysis function, wherein the display with the color difference analysis function comprises: PL module 14, PS module 12, FLASH memory unit 11, liquid crystal display panel 15. When performing the color difference analysis, the display needs to be externally connected with the colorimeter 16, and in the specific implementation, the colorimeter 16 can be replaced by a photometer.
In this embodiment, the PS module 12 and the PL module 14 are implemented by a ZYNQ Chip of xilinx, the PS module 12 is generally called a programmable System, and is composed of an SoC (System on Chip) of an ARM architecture, and in this embodiment, the PS module 12 runs an operating System of a Linux kernel to drive the colorimeter 16 to measure a color patch displayed on a display, read and write the FLASH memory unit 11, and communicate with the PL module 14 through an AXI bus.
The PL block 14, generally referred to as programmable logic, is composed of an FPGA, and in the present embodiment, the PL block 14 implements video signal de-embedding and image scaling and drives the liquid crystal display panel 15 to implement OSD interface display of color difference results.
The FLASH storage unit 11 is responsible for storing configuration information of the PL module 14 and an operating system operated by the PS module 12 according to the present invention, where the configuration information refers to a program of the PL module 14, and the PL module 14 is configured by the program, and the PL module 14 can only be started after the configuration is completed, and in a specific implementation, the FLASH storage unit 11 may select QSPI FLASH.
The specific connection relationship is as follows: the photosensitive part of the colorimeter 16 is used for measuring the liquid crystal display panel 15, the other end of the colorimeter 16 is in communication connection with the PS module 12 of the display through the USB interface 13, on one hand, the PS module 12 is used for driving the colorimeter 16 to measure color blocks displayed on the liquid crystal display panel 15, and on the other hand, the colorimeter 16 transmits measured data to the PS module 12; the PS module 12 is in communication connection with the FLASH memory unit 11 to read and write the FLASH memory unit 11, on one hand, the PS module 12 reads the color set stored in the FLASH memory unit 11 and transmits the read RGB color values to the PL module 14, and on the other hand, the PS module 12 stores the CIEXYZ measurement values measured by the colorimeter 16 in the FLASH memory unit 11; the PL module 14 is in bidirectional communication connection with the PS module 12, and the PL module 14 is used for realizing video signal de-embedding and driving the liquid crystal display panel 15 to display; the PS module 12 controls the PL module 14 to drive the liquid crystal display panel 15 to display colors in a color set through an AXI bus; meanwhile, the PS module 12 drives the colorimeter 16 to measure the above colors displayed on the liquid crystal display panel 15, and after performing calculation analysis on the above measurement data in the PS module 12, controls the PL module 14 to display the result on the liquid crystal display panel 15 in the form of an OSD (on-screen display).
When performing color difference analysis, the colorimeter 16 is connected with the display of the invention through the USB interface 13, the light-sensitive part of the colorimeter 16 is aligned with the middle part of the liquid crystal display panel 15, the other end of the colorimeter 16 is connected with the PS module 12 of the display through the USB interface 13 in a communication way, the PS module 12 drives the colorimeter 16 to measure the color displayed on the liquid crystal display panel 15, and after calculating and analyzing the measured data in the PS module 12, the PL module 14 is controlled to display the result on the liquid crystal display panel 15 in an OSD mode.
In this embodiment, the interface in the form of OSD includes a in fig. 3: CIExy gamut map of display, b: color difference histogram, c: the color difference values are averaged.
The invention also provides a color difference analysis method, which obtains the three primary color characteristics of the display, the color gamut coverage of the display and the color characteristics of the display after calculation and conversion by obtaining the CIEXYZ values of different colors displayed on the display, and displays the analysis result on the display in the form of OSD.
As shown in fig. 2, the flow of the color difference analysis method includes:
step S21: a color set is constructed that consists of several RGB color values. The color set is composed of a color label, a color name and RGB color values, in this embodiment, the color name corresponding to the color label 1 is 100% white, the corresponding RGB color values are [255, 255, 255], and so on, all the RGB color values in the color set are arranged in increments according to the color label. Where the color set must include 100% white, 100% red, 100% green, 100% blue, 100% cyan, 100% magenta, 100% yellow, and may also include some important representative colors such as: skin color, grass cyan, sky blue, etc., the number of RGB color values cannot be lower than 20 in consideration of reducing the color difference calculation error. The arrangement of color sets in this embodiment is shown in fig. 4, with a total of 30 RGB color values.
The constructed color set exists in the FLASH memory unit 11 in the form of a text file, which has the advantage that the color set can be adjusted by replacing the text file, thereby facilitating debugging and modification.
Step S22: the RGB color values in the color set are read one by one and displayed on the liquid crystal display panel 15. In this embodiment, the PS module 12 reads the color set stored in the FLASH memory unit 11, sends the RGB color values to the PL module 14 after the reading is completed, and drives the liquid crystal display panel 15 through the PL module 14 to display the RGB color values.
The PS module 12 and the PL module 14 communicate with each other by an AXI bus and register reading and writing. It is necessary to send a command to switch the PL module 14 from display mode to measurement mode before the PS module 12 sends RGB colour values to the PL module 14. The PL module 14 displays RGB color values from an external signal source, such as an SDI signal from a video camera or an HDMI signal, on the liquid crystal display panel 15 in a display mode, which is a normal operation mode of the display. In the measurement mode of the PL module 14, the liquid crystal display panel 15 displays RGB color values sent from the PS module 12, and in the measurement mode, the liquid crystal display panel 15 displays corresponding solid color patches.
Step S23: the CIEXYZ values of the color patches shown by the display were measured. After step S22 is completed, the pure color patches of the color set displayed on the liquid crystal display panel 15 are measured to obtain CIEXYZ measurement values corresponding to the RGB color values in step S22. In this embodiment, the PS module 12 drives the colorimeter 16 to sample the display through the USB interface 13.
And after the step 23 is completed, judging whether the color set is completely read, if not, continuously reading the next RGB color value in the color set, if so, storing the CIEXYZ measurement values of all the colors in the color set, and finally storing the CIEXYZ measurement values in a FLASH storage unit in a text file form, thereby facilitating the next debugging.
Step S24: the measured CIEXYZ values and RGB color values in the color set are compared against the CIEXYZ values of the reference display. It should be clear first that the same RGB colour values are input and the CIEXYZ values measured for different displays are different. And the difference between the CIEXYZ values of the current display and the CIEXYZ values of the reference display is the color difference. In this embodiment, the CIEXYZ values measured by the current display are referred to as CIEXYZ measurement values, and the CIEXYZ values of the reference display are referred to as CIEXYZ reference values. The reference display is the display with the most accurate color, and the CIEXYZ value of the reference display is determined by the reference color temperature, the reference gamma and the reference color gamut.
In step S24, 7 CIEXYZ measurement values corresponding to 7 colors of 100% white, 100% red, 100% green, 100% blue, 100% cyan, 100% magenta, and 100% yellow in the color set are extracted, the 7 CIEXYZ measurement values are color space-converted to obtain CIEYxy measurement values, and x and y components in the CIEYxy measurement values are extracted as chromaticity coordinates of the 7 colors in the CIExy coordinate system. The above 7 coordinates correspond to 7 small points in a portion a of fig. 3, the 7 small boxes are the reference positions of rec.709 color gamut on the CIExy color gamut map, that is, the chromaticity coordinates of 7 CIEXYZ reference values corresponding to 7 colors of 100% white, 100% red, 100% green, 100% blue, 100% cyan, 100% magenta, and 100% yellow, the center of the small box is the chromaticity coordinate point of the CIEXYZ reference value, and the more the small point is away from the center of the small box, the larger the color difference of the display is.
The formula for converting the CIEXYZ measurements to CIEYxy measurements is as follows:
let the three color components of the above CIEXYZ measurement be [ X, Y, Z ], and the three color components of the CIEYxy measurement be [ Lv, X, Y ]. Then, Lv is Y, X is X/(X + Y + Z), and Y is Y/(X + Y + Z).
In step S24, the RGB color values of all the colors in the color set need to be converted into CIEXYZ reference values, which are determined by the reference color temperature, the reference color gamut, and the reference gamma. In the present embodiment, the reference color temperature is D65, the reference color gamut is rec.709, and the reference gamma is 2.2. The method comprises the steps of firstly performing power calculation of 2.2 on RGB color values of all colors in a color set according to a reference gamma, then selecting a corresponding matrix NPM according to the reference gamma and a reference color gamut, and multiplying data after the power calculation by the matrix NPM to obtain CIEXYZ reference values corresponding to all the RGB color values in the color set.
The formula is as follows:
three components in the CIEXYZ reference value are [ X ]REF，YREF，ZREF]The three components of the RGB color values in the color set are [ R, G, B ]]。
Matrix array
Gamma 2.2
R′＝((R/255)γ)*100
G′＝((G/255)γ)*100
B′＝((B/255)γ)*100
As is known, CIEXYZ is a non-uniform color space, so there is a certain error in the calculated color difference, and in order to calculate the color difference more accurately, we need to convert the CIEXYZ color space into the CIELab color space, and thus in step S24, we need to perform color space conversion from CIEXYZ to CIELab on the CIEXYZ measurement values and CIEXYZ reference values, respectively.
The formula is as follows:
first, the three components of CIELab are [ L, a, b ]]Three components of the CIEXYZ measurement are [ X, Y, Z ] respectively]. Three components of the CIEXYZ measurement for 100% white in the above color set are [ X ]MAXYMAXZMAX]Three components [ X ] of CIEXYZ value corresponding to color temperature D65T，YT，ZT]＝[95.04 100 108.88]，
X′＝100*X/YMAX
Y′＝100*Y/YMAX
Z′＝100*Z/ZMAX
If X/XT，Y/YT，Z/ZTAre both greater than 0.008856, then
On the contrary, if X/XT，Y/YT，Z/ZT0.008856 or less, then:
L＝903.2963(Y′/YT)
a＝500(7.7870(X′/XT)-7.7870(Y′/YT))
b＝200(7.7870(Y′/YT)-7.7870(Z′/ZT))
after the CIEXYZ measurement value and the CIEXYZ reference value are calculated, the CIELab measurement value and the CIELab reference value can be obtained.
After obtaining the above CIELab measurement value and CIELab reference value, the color difference corresponding to all RGB color values in the color set is calculated, in this embodiment, the corresponding color difference is calculated by using the standard of Delta E2000, and the formula is as follows:
assuming that the CIELab measurement is L1，a1，b1CIELab has a reference value of L2，a2，b2And the chromatic aberration is delta E, then:
a′1＝a1(1+G)
a′2＝a2(1+G)
ΔL′＝L2-L1
ΔC′＝C′2-C＇1
RT＝-Rcsin(2Δθ)
KL＝1
KC＝1
KH＝1
step S25: and the current color rendering performance and color difference of the display are presented by using an OSD interface of the display.
In the present embodiment, an OSD interface is used to comprehensively reflect the color difference, color gamut coverage, color temperature, etc. of the display.
As shown in fig. 3, the OSD interface is further divided into three parts from top to bottom, where the first part is a in fig. 3: CIExy gamut map, the second part is b in fig. 3: color difference histogram, third part c in fig. 3: the color difference values are averaged.
The coordinate data of 7 points in the CIExy color gamut map in fig. 3 are generated by step S22, and the colors of these 7 points in the color set are: 100% white, 100% red, 100% green, 100% blue, 100% cyan, 100% magenta, 100% yellow. Wherein the approximate color temperature of the display can be judged by the coordinate position of 100% white in the above CIExy color gamut diagram. The current color gamut coverage and color reducibility of the display can be judged through the coordinate positions of the rest 6 points.
The 7 small boxes in the CIExy color gamut diagram in fig. 3 are the reference positions of the rec.709 color gamut on the CIExy color gamut diagram, and if the coordinates of the above-mentioned 7 points are located inside the small boxes, it means that the color gamut of the display is very close to the rec.709 color gamut, which means better color reduction.
Of course, the present invention is not limited to the above 7 colors, and more colors including the above 7 colors may be used to obtain a better color evaluation result.
The color difference histogram in fig. 3 shows a color difference histogram of a plurality of colors in a color set, and a user can determine whether the color difference of the plurality of colors meets requirements through the histogram, wherein the colors include representative colors such as 100% white, 100% red, 100% green, 100% blue, 100% cyan, 100% magenta, 100% yellow, sky blue, grass cyan, skin color, and the like, and the user can determine whether the display needs to be corrected through the color difference of the representative colors. In FIG. 3, W is 100% white, R is 100% red, G is 100% green, B is 100% blue, Cy is 100% cyan, Mg is 100% magenta, and Y1 is 100% yellow.
In the average color difference in fig. 3, the average color difference value of all colors in the color set is given, which is convenient for the user to make a quantitative judgment.
In the present invention, the following concepts need to be clarified:
the CIEXYZ measurement value represents the actual 'tri-stimulus value' information of the measured color, namely the stimulation and the feeling of the color spectrum to human eyes, and is biased to the level of the physical spectrum;
CIEYxy: performing linear calculation on CIEXYZ, separating the brightness and the chromaticity, wherein the calculated Y represents the brightness, and the x and the Y represent the chromaticity;
the CIExy chromaticity coordinates refer to the coordinates of x and y in the CIEYxy;
the CIExy color gamut map is a two-dimensional plane formed by the above x and y coordinates, and the CIExy chromaticity coordinates of XX color on the two-dimensional plane can be used to represent color gamut information, and the CIExy chromaticity coordinates of gray and white color on the map are the same because the map does not contain luminance information;
CIELab: also based on CIEXYZ, and CIELab also separates luminance and chrominance, which has the advantage of "uniformity", where the color difference can be expressed in terms of distance.
Claims (10)
1. A chromatic aberration analysis method is characterized in that: the method comprises the following steps:
s1, constructing color sets with the number of colors not less than 20, wherein the color sets comprise 100% white, 100% red, 100% green, 100% blue, 100% cyan, 100% magenta and 100% yellow;
s2, measuring color blocks of all colors in the color set displayed by the display to obtain CIEXYZ measurement values of all colors in the color set;
s3, taking the CIEXYZ measured values of 7 colors of 100% white, 100% red, 100% green, 100% blue, 100% cyan, 100% magenta and 100% yellow in the step S2, carrying out color space conversion to obtain CIEYxy measured values, and taking an x component and a y component in the CIEYxy measured values as chromaticity coordinates of the 7 colors in a CIExy coordinate system;
s4, converting the RGB color values of all colors in the color set into CIEXYZ reference values;
s5, converting the CIEXYZ measured values and CIEXYZ reference values of all colors in the color set into CIELab measured values and CIELab reference values through a color space respectively;
and S6, calculating the color difference between the CIELab measured value and the CIELab reference value of all the colors in the color set.
2. The color difference analysis method according to claim 1, characterized in that: further comprising: the chromaticity coordinates of the 7 colors in step S3 and the color difference in step S6 are displayed in the form of OSD.
3. The color difference analysis method according to claim 1 or 2, characterized in that: the color set in step S1 further includes sky blue, skin color, and grass cyan.
4. The color difference analysis method according to claim 1 or 2, characterized in that: the three color components of the CIEYxy measurement value obtained through the color space conversion in step S3 are [ Lv, X, Y ], where Lv is Y, X is X/(X + Y + Z), and Y is Y/(X + Y + Z), where [ X, Y, Z ] are the three color components of the CIEXYZ measurement value, respectively.
5. The color difference analysis method according to claim 1 or 2, characterized in that: the CIEXYZ reference value in step S4 is obtained by calculating all RGB color values in the color set with a reference color temperature D65, a reference color gamut rec.709, and a reference gamma of 2.2.
6. The color difference analysis method according to claim 1 or 2, characterized in that: the color difference in step S6 is calculated by using the Delta E2000 standard.
7. A display with chromatic aberration analysis function is characterized in that: the device comprises a FLASH storage unit, a PS module, a PL module and a liquid crystal display panel; the PS module is in communication connection with the PL module, the colorimeter and the FLASH storage unit respectively, the PL module is in communication connection with the liquid crystal display panel, the PS module reads RGB chromaticity with concentrated color from the FLASH storage unit and transmits the RGB chromaticity to the PL module, and the PS module controls the PL module to display color blocks with concentrated color on the liquid crystal display panel; the PS module drives the colorimeter to measure color blocks on the liquid crystal display panel, data obtained by measurement of the colorimeter are stored in the FLASH storage unit, and after the PS module performs color difference analysis on the measured data, the PL module is controlled to display color difference analysis results on the liquid crystal display panel in an OSD mode.
8. The display with chromatic aberration analysis function of claim 7, characterized in that: the colorimeter is in communication connection with the PS module through a USB interface.
9. The display with chromatic aberration analysis function of claim 7, characterized in that: and the PS module and the PL module realize communication through AXI bus and register reading and writing.
10. The display with chromatic aberration analysis function of claim 7, characterized in that: the OSD displaying includes: CIExy color gamut map, color difference histogram, average color difference value.
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