CN109979382B - Screen transmission spectrum-based color correction method and system for under-screen imaging system - Google Patents

Screen transmission spectrum-based color correction method and system for under-screen imaging system Download PDF

Info

Publication number
CN109979382B
CN109979382B CN201910329613.2A CN201910329613A CN109979382B CN 109979382 B CN109979382 B CN 109979382B CN 201910329613 A CN201910329613 A CN 201910329613A CN 109979382 B CN109979382 B CN 109979382B
Authority
CN
China
Prior art keywords
screen
imaging system
under
color
compensation matrix
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN201910329613.2A
Other languages
Chinese (zh)
Other versions
CN109979382A (en
Inventor
曹良才
李儒佳
卢建强
杨鑫
吴佳琛
张华�
金国藩
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Tsinghua University
Guangdong Oppo Mobile Telecommunications Corp Ltd
Original Assignee
Tsinghua University
Guangdong Oppo Mobile Telecommunications Corp Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Tsinghua University, Guangdong Oppo Mobile Telecommunications Corp Ltd filed Critical Tsinghua University
Priority to CN201910329613.2A priority Critical patent/CN109979382B/en
Publication of CN109979382A publication Critical patent/CN109979382A/en
Application granted granted Critical
Publication of CN109979382B publication Critical patent/CN109979382B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
    • G09G3/006—Electronic inspection or testing of displays and display drivers, e.g. of LED or LCD displays
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
    • G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
    • G09G3/22—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources
    • G09G3/30—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources using electroluminescent panels
    • G09G3/32—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources using electroluminescent panels semiconductive, e.g. using light-emitting diodes [LED]
    • G09G3/3208—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources using electroluminescent panels semiconductive, e.g. using light-emitting diodes [LED] organic, e.g. using organic light-emitting diodes [OLED]
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N17/00—Diagnosis, testing or measuring for television systems or their details
    • H04N17/002—Diagnosis, testing or measuring for television systems or their details for television cameras
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N23/00—Cameras or camera modules comprising electronic image sensors; Control thereof
    • H04N23/80—Camera processing pipelines; Components thereof
    • H04N23/81—Camera processing pipelines; Components thereof for suppressing or minimising disturbance in the image signal generation

Abstract

The invention discloses a color correction method and a color correction system for an off-screen imaging system based on screen transmission spectrum, which mainly aim at correcting the color cast problem generated by an acquired image when the off-screen imaging system is used for carrying out off-screen imaging through a screen. Wherein, the method comprises the following steps: firstly, obtaining the distribution of the transmittance of a screen sample along with the wavelength; generating an initial compensation matrix according to the distribution to compensate the under-screen imaging system; carrying out imaging test on the compensated and corrected under-screen imaging system and acquiring a test image; correcting the compensation matrix according to the test image, and compensating the color cast phenomenon of the under-screen imaging system by using the corrected compensation matrix; and finally, continuously correcting the compensation matrix according to the test result until the color cast condition is further weakened and meets the use requirement, and correcting the color cast phenomenon of the under-screen imaging system. The method can enable the under-screen imaging system to carry out color difference-free imaging on objects at infinity, and particularly carry out under-screen imaging on the front camera of the mobile equipment.

Description

Screen transmission spectrum-based color correction method and system for under-screen imaging system
Technical Field
The invention relates to the technical field of image processing, in particular to a color correction method and system of an under-screen imaging system based on screen transmission spectrum.
Background
For the under-screen imaging system, since the OLED (Organic Light Emitting Diode) screen is a multi-layer display device made of a transparent material with a certain transmittance, when the under-screen imaging is performed through the OLED screen, the transmittance of each band of Light in the white Light incident into the under-screen imaging system in the OLED screen is different, so that when the under-screen imaging system is used to shoot an image, the obtained image color is distorted compared with the shooting target scene. To address this problem, color calibration corrections need to be made to the off-screen imaging system.
The current domestic commercial camera correction method is completed based on a D65 light source and a reflective standard color plate. The method utilizes the imaging result of the imaging system to be corrected to establish a corresponding relation with the RGB (standard industrial color mode) value of the corresponding color block in the standard color card, thereby completing the correction. Meanwhile, different color calibration methods exist for different digital imaging systems. For example, a multispectral camera color correction method, aiming at a satellite multispectral camera, the method is used for comparing an image formed by a standard color block under uniform illumination light generated by an integrating sphere light source with a real result of the standard color block to finish the color correction of a space remote sensing multispectral camera, but the method is not suitable for flow line production and calibration scenes, so that the color correction of an imaging system under an OLED screen of portable electronic equipment is necessary.
Disclosure of Invention
The present invention is directed to solving, at least to some extent, one of the technical problems in the related art.
To this end, an object of the present invention is to provide a method for color correction of an under-screen imaging system based on the transmission spectrum of a screen.
Another objective of the present invention is to provide an under-screen imaging system color correction system based on the transmission spectrum of the screen.
In order to achieve the above object, the present invention provides a color correction method for an under-screen imaging system based on screen transmission spectrum, comprising the following steps: step S1, acquiring a transmissivity curve of an OLED screen sample by using a spectrometer; step S2, determining an initial compensation matrix of the OLED screen sample according to the transmissivity curve; step S3, pre-calibrating the under-screen imaging system by using the initial compensation matrix; step S4, the pre-calibrated under-screen imaging system is used for carrying out photographing test on the standard color card, and RGB three-channel test values of corresponding areas in the test results are obtained; step S5, comparing the RGB three channel test values of the corresponding area with the color standard value in the standard card to determine a compensation matrix; and S6, calibrating the under-screen imaging system by using the compensation matrix, performing imaging test on the standard color card, judging whether a color cast phenomenon exists, repeating the steps S4-S6 if the color cast phenomenon exists, and outputting a compensation result if the color cast phenomenon does not exist.
The color correction method of the under-screen imaging system based on the screen transmission spectrum comprises the steps of pre-calibrating the under-screen imaging system by utilizing the screen sample transmission spectrum obtained by a spectrometer according to the spectrum, carrying out shooting test on a standard color card by utilizing the pre-calibrated system to obtain an average calibration value, calculating a compensation matrix, and continuously correcting the compensation matrix according to a test result, so that the color cast phenomenon of the under-screen imaging system is corrected, particularly, under-screen imaging is carried out by using a front camera of a mobile phone or other mobile equipment, and the method is suitable for the color correction of an assembly line production and calibration scene and an OLED (organic light emitting diode) under-screen imaging system of portable electronic equipment.
In addition, the color correction method for the under-screen imaging system based on the transmission spectrum of the screen according to the above embodiment of the present invention may further have the following additional technical features:
further, in an embodiment of the present invention, the step S1 further includes: and measuring the OLED screen sample by using a transmission spectrometer to obtain transmittance curves under different wavelengths.
Further, in an embodiment of the present invention, in the step S2, an initial compensation matrix of the OLED screen sample is determined by calculating the transmittance curve to obtain an average transmittance, wherein the initial compensation matrix is for three RGB channels.
Further, in an embodiment of the present invention, the pre-calibration relationship between RGB of the pre-calibrated under-screen imaging system and RGB of the OLED screen sample is:
Figure BDA0002037276650000021
wherein R, G, B represent three channels of the OLED screen sample, C0,3×3Representing the initial compensation matrix, R0，G0，B0Three channels of the pre-calibrated under-screen imaging system are represented.
Further, in an embodiment of the present invention, in the step S4, if the standard color chart is used as the test target, only the first three rows of color block portions need to be selected for data acquisition processing.
In order to achieve the above object, another aspect of the present invention provides an off-screen imaging system color correction system based on screen transmission spectrum, comprising: the acquisition module is used for acquiring a transmissivity curve of the OLED screen sample by using a spectrometer; the initialization module is used for determining an initial compensation matrix of the OLED screen sample according to the transmittance curve; the pre-calibration module is used for pre-calibrating the under-screen imaging system by using the initial compensation matrix; the test module is used for carrying out photographing test on the standard color card by using the pre-calibrated under-screen imaging system to obtain RGB three-channel test values of corresponding areas in the test result; the comparison module is used for comparing the RGB three channel test values of the corresponding area with the color standard value in the standard card to determine a compensation matrix; the judgment module is used for calibrating the under-screen imaging system by using the compensation matrix, carrying out imaging test on the standard color card, judging whether a color cast phenomenon exists or not, and outputting a compensation result if the color cast phenomenon does not exist.
The color correction system of the under-screen imaging system based on the screen transmission spectrum is used for correcting the color cast phenomenon of the under-screen imaging system by pre-calibrating the under-screen imaging system according to the spectrum through the screen sample transmission spectrum obtained by a spectrometer, then carrying out shooting test on a standard color card by using the pre-calibrated system to obtain an average calibration value, calculating a compensation matrix and continuously correcting the compensation matrix according to a test result, particularly carrying out under-screen imaging by using a front camera of a mobile phone or other mobile equipment, and is suitable for the color correction of an assembly line production and calibration scene and an OLED (organic light emitting diode) under-screen imaging system of portable electronic equipment.
In addition, the color correction system of the off-screen imaging system based on the screen transmission spectrum according to the above embodiment of the invention may also have the following additional technical features:
further, in an embodiment of the present invention, the obtaining module further includes: and measuring the OLED screen sample by using a transmission spectrometer to obtain transmittance curves under different wavelengths.
Further, in an embodiment of the present invention, in the initialization module, an initial compensation matrix of the OLED screen sample is determined by calculating the transmittance curve to obtain an average transmittance, wherein the initial compensation matrix is for three channels of RGB.
Further, in an embodiment of the present invention, the pre-calibration relationship between RGB of the pre-calibrated under-screen imaging system and RGB of the OLED screen sample is:
Figure BDA0002037276650000031
wherein R, G, B represent three channels of the OLED screen sample, C0,3×3Representing the initial compensation matrix, R0，G0，B0Three channels of the pre-calibrated under-screen imaging system are represented.
Further, in an embodiment of the present invention, in the test module, if the standard color chart is used as a test target, only the first three rows of color block portions need to be selected for data acquisition processing.
Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.
Drawings
The foregoing and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:
FIG. 1 is a flow chart of a method for color correction of an off-screen imaging system based on screen transmission spectra according to an embodiment of the invention;
FIG. 2 is a flowchart illustrating a color correction method for an off-screen imaging system based on screen transmission spectrum according to an embodiment of the present invention;
FIG. 3 is a graph showing transmittance curves of screen samples according to an embodiment of the present invention;
FIG. 4 is a schematic diagram of a color standard color chart according to an embodiment of the present invention;
FIG. 5 is a diagram illustrating RGB values corresponding to some colors in a standard color chart according to an embodiment of the present invention;
FIG. 6 is a schematic diagram of a color correction system of an off-screen imaging system based on screen transmission spectrum according to an embodiment of the present invention.
Detailed Description
Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are illustrative and intended to be illustrative of the invention and are not to be construed as limiting the invention.
The method and system for correcting the color of the under-screen imaging system based on the transmission spectrum of the screen according to the embodiment of the invention will be described with reference to the accompanying drawings.
FIG. 1 is a flow chart of a method for color correction of an off-screen imaging system based on screen transmission spectra according to an embodiment of the invention.
As shown in FIG. 1, the color correction method of the under-screen imaging system based on the transmission spectrum of the screen comprises the following steps:
in step S1, a transmittance curve of the OLED screen sample is acquired using a spectrometer.
Further, in step S1, in the embodiment of the present invention, the OLED screen sample is measured by using a transmission spectrometer, so as to obtain transmittance curves at different wavelengths. The transmittance curve may also be referred to as a transmission spectrum curve.
In step S2, an initial compensation matrix for the OLED screen sample is determined from the transmittance curve.
That is, from the screen sample transmission spectral distribution, a color pre-calibration matrix for the three channels of RGB is obtained.
Further, in the embodiment of the present invention, in step S2, an initial compensation matrix of the OLED screen sample is determined by calculating a transmittance curve to obtain an average transmittance, where the initial compensation matrix is for three channels of RGB.
It can be understood that the embodiment of the present invention performs a transmission spectrum test on the OLED screen, and determines the pre-calibration matrix according to the transmittance at three wavelength bands of the industry standard RGB.
In step S3, the off-screen imaging system is pre-calibrated using the initial compensation matrix.
It is understood that the generated pre-calibration matrix is used to pre-calibrate the images taken by the off-screen imaging system.
The pre-calibration relation between the RGB of the pre-calibrated under-screen imaging system and the RGB of the OLED screen sample is as follows:
Figure BDA0002037276650000041
wherein R, G, B represent three channels of the OLED screen sample, C0,3×3Representing an initial compensation matrix, R0，G0，B0Three channels of the pre-calibrated under-screen imaging system are shown.
In step S4, the pre-calibrated under-screen imaging system is used to perform a photographing test on the standard color card, and RGB three-channel test values in the corresponding region in the test result are obtained.
If the standard color card is used as a test target, only the first three rows of color block parts need to be selected for data acquisition and processing.
And after the test is finished, comparing the RGB value of the standard color card with the RGB value of the test result, and generating a correction matrix by using the difference value.
In step S5, the RGB three-channel test values of the corresponding area are compared with the standard color values in the standard card to determine a compensation matrix.
That is, the compensation matrix is obtained according to the difference between the standard RGB value and the test value of each part of the standard color card.
In step S6, the compensation matrix is used to calibrate the under-screen imaging system, and the standard color card is subjected to an imaging test to determine whether a color cast phenomenon exists, if so, steps S4-S6 are repeated, and if not, a compensation result is output.
In summary, as shown in fig. 2, the calibration method of the embodiment of the invention includes: firstly, testing a screen sample transmission spectrum used by an imaging system under a screen by using a spectrometer; calculating an initial compensation matrix C from the obtained projection spectrum0,3×3(ii) a After the initial color correction is carried out on the imaging system under the screen by using the initial compensation matrix, the pre-corrected system is used for shooting a standard color card S0,m×nObtaining a test value Ti,m×n(ii) a Calculating a correction compensation matrix C by using the difference between the color channel corresponding values between the test value and the standard valuei,3×3(ii) a And shooting the standard color card again, and repeating the correction process according to the requirement.
In the first embodiment, taking RGB as an example, the specific steps are as follows:
(1) measuring a screen used by an imaging system under the screen by using a transmission spectrometer to obtain transmittance curves under different wavelengths, and respectively obtaining average transmittances t of the three required imaging systems under the working wavelengths of 700nm, 546.1nm and 435.8nm and the bandwidth of 10nmλ。
(2) Tong (Chinese character of 'tong')Obtaining an initial color compensation matrix C based on the transmission spectrum of the screen sample according to the obtained average transmittance at different wavelengths0,3×3The expression should be as follows:
Figure BDA0002037276650000051
(3) using an initial color compensation matrix C0,3×3If the off-screen imaging system is pre-calibrated, the relationship between the pre-calibrated RGB of the off-screen imaging system and the RGB of the captured image can be expressed as:
Figure BDA0002037276650000052
(4) shooting standard color chip S by using under-screen imaging system0,m×nObtaining a test value Ti,m×nAnd m and n respectively represent the number of rows and columns of different standard test color blocks in the field of view of the imaging system under the screen. Take the color block distribution of the standard color card under RGB condition as an example, S0,m×nCan be expressed in the following form. If the standard color card is used as a test target, only the first three rows of color blocks are selected for data acquisition and processing.
Figure BDA0002037276650000061
(5) Will T0,m×nRespectively comparing the RGB value in each color block with the standard color value in the standard color card to obtain the RGB difference value between the standard color value and the RGB value, and determining the compensation matrix C according to the average value of the difference valuesi,3×3。
Figure BDA0002037276650000062
(6) According to a compensation matrix Ci,3×3The compensated under-screen imaging system RGB values are obtained as:
Figure BDA0002037276650000063
and (4) repeating the steps (4) to (6) according to actual requirements until the test value of the under-screen imaging system on the standard color card is the same as the value of the standard color card.
In a second embodiment, a system color correction method for performing an off-screen imaging on a transparent top-emitting OLED screen is taken as an example, and the specific steps are as follows:
(1) the screen used in the off-screen imaging system was measured using a transmission spectrometer to obtain the wavelength versus transmission curve shown in figure 3. Because of the imaging system, RGB has corresponding wavelengths. The reference wavelength of R red light is 700nm according to the RGB three primary colors wavelength determined by the International Commission on illumination in 1931; the reference wavelength of the G green light is 546.1 nm; the reference wavelength of the blue light B is 435.8nm, the three wavelengths are selected as characteristic wavelengths, and the average transmittance of 10nm in bandwidth under the three wavelengths is obtained respectively. In the embodiment of the invention, the average transmittance of blue light is 41.15%, the average transmittance of green light is 51.51%, and the average transmittance of red light is 48.70%. The normalized transmittances were: blue light 0.7989, green light 1, red light 0.9454.
(2) Obtaining an initial color compensation matrix C based on the transmission spectrum of the screen sample0,3×3The expression should be as follows:
Figure BDA0002037276650000064
(3) using an initial color compensation matrix C0,3×3If the OLED display screen used in the off-screen imaging system in this example is pre-calibrated, the pre-calibration relationship between the pre-calibrated RGB of the off-screen imaging system and the RGB of the captured image can be expressed as:
Figure BDA0002037276650000071
(4) photographing a standard color chart S as shown in FIG. 4 using an off-screen imaging system0,m×nAnd obtaining a test value Ti,m×nWherein m is,n respectively represents the number of rows and columns of different standard test color blocks in the field of view of the imaging system under the screen.
Take the color block distribution of the standard color card under RGB condition as an example, S0,m×nCan be expressed in the following form. If the standard color card shown in fig. 4 is used as a test target, only the first three rows of color blocks need to be selected for data acquisition.
Figure BDA0002037276650000072
(5) Will T0,m×nThe RGB values in each color block are compared with the standard values shown in FIG. 5, respectively, to obtain an RGB difference matrix T with the standard valuesΔAnd determining a compensation matrix based on the average of the differences
Figure BDA0002037276650000073
Figure BDA0002037276650000074
(6) According to a compensation matrix
Figure BDA0002037276650000075
The compensated under-screen imaging system RGB values are obtained as:
Figure BDA0002037276650000076
and (4) repeating the steps (4) to (6) according to the actual requirement, and performing cycle optimization until the use requirement is met.
According to the color correction method of the under-screen imaging system based on the screen transmission spectrum, which is provided by the embodiment of the invention, the under-screen imaging system is pre-calibrated by utilizing the screen sample transmission spectrum obtained by a spectrometer according to the spectrum, then the pre-calibrated system is utilized to carry out shooting test on a standard color card to obtain an average calibration value, a compensation matrix is calculated, and the compensation matrix is continuously corrected according to the test result, so that the color cast phenomenon of the under-screen imaging system is corrected, especially the under-screen imaging is carried out by using a front camera of a mobile phone or other mobile equipment.
Next, a color correction system for an under-screen imaging system based on a transmission spectrum of a screen according to an embodiment of the present invention will be described with reference to the accompanying drawings.
FIG. 6 is an under-screen imaging system color correction system based on screen transmission spectra in accordance with one embodiment of the present invention.
As shown in fig. 6, the color correction system 10 for an off-screen imaging system based on screen transmission spectrum comprises: the device comprises an acquisition module 100, an initialization module 200, a pre-calibration module 300, a test module 400, a comparison module 500 and a judgment module 600.
The obtaining module 100 is configured to obtain a transmittance curve of the OLED screen sample by using a spectrometer. The initialization module 200 is used to determine an initial compensation matrix for the OLED screen sample from the transmittance curve. The pre-calibration module 300 is used to pre-calibrate the off-screen imaging system using the initial compensation matrix. The test module 400 is configured to perform a photographing test on the standard color card by using the pre-calibrated under-screen imaging system, and obtain RGB three-channel test values of a corresponding region in the test result. The comparison module 500 is used for comparing the RGB three-channel test values of the corresponding area with the color standard values in the standard card to determine the compensation matrix. The determining module 600 is configured to calibrate the under-screen imaging system by using the compensation matrix, perform an imaging test on the standard color card, determine whether a color cast phenomenon exists, and output a compensation result if the color cast phenomenon does not exist.
It is understood that the system of the embodiment of the invention comprises: the device comprises components such as a spectrometer, a reflective standard color card, a screen sample used by the under-screen imaging system, an under-screen imaging system module and the like.
Further, in an embodiment of the present invention, the obtaining module further includes: and measuring the OLED screen sample by using a transmission spectrometer to obtain the transmittance curves under different wavelengths.
Further, in one embodiment of the present invention, in the initialization module, the initial compensation matrix of the OLED screen sample is determined by calculating the transmittance curve to obtain the average transmittance, wherein the initial compensation matrix is for the RGB three channels.
Further, in an embodiment of the present invention, the pre-calibration relationship between RGB of the pre-calibrated under-screen imaging system and RGB of the OLED screen sample is:
Figure BDA0002037276650000081
wherein R, G, B represent three channels of the OLED screen sample, C0,3×3Representing an initial compensation matrix, R0，G0，B0Three channels of the pre-calibrated under-screen imaging system are shown.
Further, in an embodiment of the present invention, in the test module, if the standard color chart is used as the test target, only the first three rows of color block portions need to be selected for data acquisition processing.
It should be noted that the foregoing explanation of the embodiment of the color correction method for an under-screen imaging system based on the transmission spectrum of a screen is also applicable to the system, and is not repeated here.
According to the color correction system of the under-screen imaging system based on the screen transmission spectrum, which is provided by the embodiment of the invention, the under-screen imaging system is pre-calibrated by using the screen sample transmission spectrum obtained by a spectrometer according to the spectrum, then the pre-calibrated system is used for carrying out shooting test on a standard color card to obtain an average calibration value, a compensation matrix is calculated, and the compensation matrix is continuously corrected according to the test result, so that the color cast phenomenon of the under-screen imaging system is corrected, especially the under-screen imaging is carried out by using a front camera of a mobile phone or other mobile equipment.
Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.
In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.
In the present invention, unless otherwise expressly stated or limited, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through an intermediate. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.
In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.
Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations can be made to the above embodiments by those of ordinary skill in the art within the scope of the present invention.

Claims (6)

1. A color correction method of an under-screen imaging system based on screen transmission spectrum is characterized by comprising the following steps:
step S1, obtaining a transmittance curve of an OLED screen sample by using a spectrometer, wherein the OLED screen sample is measured by using a transmission spectrometer to obtain transmittance curves under different wavelengths;
step S2, determining an initial compensation matrix of the OLED screen sample according to the transmittance curve, wherein the initial compensation matrix of the OLED screen sample is determined by calculating the transmittance curve to obtain an average transmittance, and the initial compensation matrix is for three channels of RGB;
step S3, pre-calibrating the under-screen imaging system by using the initial compensation matrix;
step S4, the pre-calibrated under-screen imaging system is used for carrying out photographing test on the standard color card, and RGB three-channel test values of corresponding areas in the test results are obtained;
step S5, comparing the RGB three channel test values of the corresponding area with the color standard value in the standard color card to determine a compensation matrix; and
and S6, calibrating the under-screen imaging system by using the compensation matrix, performing imaging test on the standard color card, judging whether a color cast phenomenon exists, repeating the steps S4-S6 if the color cast phenomenon exists, and outputting a compensation result if the color cast phenomenon does not exist.
2. The method for color correction of an off-screen imaging system based on screen transmission spectrum of claim 1, wherein the pre-calibration relationship between the RGB of the pre-calibrated off-screen imaging system and the RGB of the OLED screen sample is:
Figure DEST_PATH_FDA0002667222270000011
wherein R, G, B represent three channels of the OLED screen sample, C0,3× 3 Representing the initial compensation matrix, R0，G0 ，B0Three channels of the pre-calibrated under-screen imaging system are represented.
3. The color correction method for screen transmission spectrum based underscreen imaging system of claim 1, wherein in said step S4, if said standard color chart is used as a test target, only the first three rows of color block portions need to be selected for data acquisition processing.
4. An off-screen imaging system color correction system based on screen transmission spectra, comprising:
the device comprises an acquisition module, a transmission module and a control module, wherein the acquisition module is used for acquiring a transmittance curve of an OLED screen sample by using a spectrometer, and the transmission curve under different wavelengths is acquired by measuring the OLED screen sample by using a transmission spectrometer;
an initialization module, configured to determine an initial compensation matrix of the OLED screen sample according to the transmittance curve, wherein an average transmittance is obtained by calculating the transmittance curve to determine the initial compensation matrix of the OLED screen sample, and the initial compensation matrix is for three RGB channels;
the pre-calibration module is used for pre-calibrating the under-screen imaging system by utilizing the initial compensation matrix;
the test module is used for carrying out photographing test on the standard color card by using the pre-calibrated under-screen imaging system to obtain RGB three-channel test values of corresponding areas in the test result;
the comparison module is used for comparing the RGB three channel test values of the corresponding area with the color standard value in the standard color card to determine a compensation matrix; and
and the judging module is used for calibrating the under-screen imaging system by using the compensation matrix, carrying out imaging test on the standard color card, judging whether a color cast phenomenon exists or not, and outputting a compensation result if the color cast phenomenon does not exist.
5. The under-screen imaging system color correction system based on screen transmission spectrum of claim 4, wherein the pre-calibrated relationship between RGB of the under-screen imaging system and RGB of the OLED screen sample is:
Figure DEST_PATH_FDA0002667222270000021
wherein R, G, B represent three channels of the OLED screen sample, C0,3× 3 Representing the initial compensation matrix, R0，G0 ，B0Three channels of the pre-calibrated under-screen imaging system are represented.
6. The color correction system for an under-screen imaging system based on screen transmission spectrum of claim 4, wherein in the testing module, if the standard color chart is used as a testing target, only the first three rows of color block parts need to be selected for data acquisition processing.
CN201910329613.2A 2019-04-23 2019-04-23 Screen transmission spectrum-based color correction method and system for under-screen imaging system Active CN109979382B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201910329613.2A CN109979382B (en) 2019-04-23 2019-04-23 Screen transmission spectrum-based color correction method and system for under-screen imaging system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201910329613.2A CN109979382B (en) 2019-04-23 2019-04-23 Screen transmission spectrum-based color correction method and system for under-screen imaging system

Publications (2)

Publication Number Publication Date
CN109979382A CN109979382A (en) 2019-07-05
CN109979382B true CN109979382B (en) 2021-02-23

Family

ID=67085944

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201910329613.2A Active CN109979382B (en) 2019-04-23 2019-04-23 Screen transmission spectrum-based color correction method and system for under-screen imaging system

Country Status (1)

Country Link
CN (1) CN109979382B (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11954833B2 (en) 2021-04-02 2024-04-09 Samsung Electronics Co., Ltd Electronic device for supporting machine learning-based image processing

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110460825A (en) * 2019-08-02 2019-11-15 武汉华星光电半导体显示技术有限公司 A kind of imaging compensating device, imaging compensating method and its application
CN112449085A (en) * 2019-08-30 2021-03-05 北京小米移动软件有限公司 Image processing method and device, electronic equipment and readable storage medium
CN110636225B (en) * 2019-10-23 2021-06-15 维沃移动通信有限公司 Photographing method and electronic equipment
CN111311523B (en) * 2020-03-26 2023-09-05 北京迈格威科技有限公司 Image processing method, device and system and electronic equipment
CN112004077B (en) * 2020-08-17 2022-06-07 Oppo（重庆）智能科技有限公司 Calibration method and device for off-screen camera, storage medium and electronic equipment
CN112133197B (en) * 2020-09-29 2022-09-13 厦门天马微电子有限公司 Display screen, optical compensation method and optical compensation system of under-screen camera in display screen

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2002209230A (en) * 2000-12-29 2002-07-26 Totoku Electric Co Ltd Color calibration device for display device and the display device
CN101226730A (en) * 2007-01-18 2008-07-23 中兴通讯股份有限公司 Method and apparatus for managing color of mobile terminal
CN102063888A (en) * 2009-11-13 2011-05-18 京东方科技集团股份有限公司 Method and device for managing colors
JP4834896B2 (en) * 1997-10-31 2011-12-14 ソニー株式会社 Image processing apparatus and method, image transmission / reception system and method, and recording medium
CN102778201A (en) * 2011-05-13 2012-11-14 索尼公司 Image processing device, image processing method, and program
CN104902153A (en) * 2015-05-25 2015-09-09 北京空间机电研究所 Color correction method for multi-spectrum cameras
CN108668122A (en) * 2017-03-31 2018-10-16 宁波舜宇光电信息有限公司 Color rendition method and equipment for spectral response curve

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4834896B2 (en) * 1997-10-31 2011-12-14 ソニー株式会社 Image processing apparatus and method, image transmission / reception system and method, and recording medium
JP2002209230A (en) * 2000-12-29 2002-07-26 Totoku Electric Co Ltd Color calibration device for display device and the display device
CN101226730A (en) * 2007-01-18 2008-07-23 中兴通讯股份有限公司 Method and apparatus for managing color of mobile terminal
CN102063888A (en) * 2009-11-13 2011-05-18 京东方科技集团股份有限公司 Method and device for managing colors
CN102778201A (en) * 2011-05-13 2012-11-14 索尼公司 Image processing device, image processing method, and program
CN104902153A (en) * 2015-05-25 2015-09-09 北京空间机电研究所 Color correction method for multi-spectrum cameras
CN108668122A (en) * 2017-03-31 2018-10-16 宁波舜宇光电信息有限公司 Color rendition method and equipment for spectral response curve

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11954833B2 (en) 2021-04-02 2024-04-09 Samsung Electronics Co., Ltd Electronic device for supporting machine learning-based image processing

Also Published As

Publication number Publication date
CN109979382A (en) 2019-07-05

Similar Documents

Publication Publication Date Title
CN109979382B (en) Screen transmission spectrum-based color correction method and system for under-screen imaging system
CN107197225B (en) Color digital camera white balance correcting based on chromatic adaptation model
US7570881B2 (en) Color balanced camera with a flash light unit
WO2012004910A1 (en) Imaging device and color temperature calculation method
CN107256689B (en) Uniformity repairing method for LED display screen after brightness correction
US7616314B2 (en) Methods and apparatuses for determining a color calibration for different spectral light inputs in an imaging apparatus measurement
US20070177032A1 (en) Automatic color calibration of an image sensor
CN113170028A (en) Method for generating image data of imaging algorithm based on machine learning
JP6530751B2 (en) Image processing apparatus, imaging apparatus, information processing apparatus, image processing method and program
US8659685B2 (en) Method and apparatus for calibrating and correcting shading non-uniformity of camera systems
CN111292246B (en) Image color correction method, storage medium, and endoscope
CN103647958B (en) Image processing method, image processing apparatus and electronic equipment
JP2016194456A (en) Color fidelity environment correction device and color fidelity environment correction method
CN107479222B (en) Measuring method and device for measuring display panel
WO2003103298A1 (en) Multiprojection system and correction data acquiring method for multiprojection system
CN113676639A (en) Image processing method, processing device, electronic apparatus, and medium
JP2007093477A (en) Method and apparatus of calibrating color measuring device, and color measuring method and device
JP5899894B2 (en) Imaging apparatus, image processing apparatus, image processing program, and image processing method
US9036030B2 (en) Color calibration of an image capture device in a way that is adaptive to the scene to be captured
US10009605B1 (en) Multi-camera filter system for characterizing display panels
JP2010139324A (en) Color irregularity measuring method and color irregularity measuring device
GB2411309A (en) Manual white balance using arbitrary surface
CN111896109B (en) Spectrum reconstruction method based on original response value of digital camera
JP2006108988A (en) Calibration device
US10937230B2 (en) Image processing

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant