WO2022040889A1

WO2022040889A1 - Display method and apparatus, and electronic device

Info

Publication number: WO2022040889A1
Application number: PCT/CN2020/110917
Authority: WO
Inventors: 刘洋; 刘海啸; 李睿哲
Original assignee: 华为技术有限公司
Priority date: 2020-08-24
Filing date: 2020-08-24
Publication date: 2022-03-03
Also published as: CN115918066A

Abstract

Embodiments of the present disclosure provide a display method and apparatus, and an electronic device. The method comprises: acquiring a first RGB of a first pixel to be displayed; acquiring a third display lookup table (LUT) corresponding to a first application mode, the third LUT being generated by means of fusion between a first LUT and a second LUT which corresponds to the first application mode and comprising one-to-one correspondences between multiple first initial RGBs and first display RGBs, the first LUT comprising one-to-one mapping relationships between the multiple first initial RGBs and target RGBs, the second LUT comprising one-to-one mapping relationships between multiple second initial RGBs and display RGBs; and determining, according to the third LUT, the second RGB which the first RGB corresponds to in the first application mode, and sending the second RGB to a first display for displaying. According to the embodiments of the present disclosure, the efficiency and accuracy of color space conversion by the display screen can be effectively improved.

Description

A display method, device and electronic device

technical field

The present application relates to the field of display technology, and in particular, to a display method, device and electronic device.

Background technique

Color gamut is a method of encoding a color, and also refers to the totality of colors that a technical system can produce. In computer graphics, a color gamut is some complete subset of colors. The most common application of color subsets is to accurately represent a given situation. For example, a given color space or the color rendering range of an output device. For different monitors, the displayed color gamut is different, resulting in the same graphics being displayed differently on different monitors. The objectively measured indicators can be quantified according to the CIE1931 color space.

The CIE 1931 color space (also known as the CIE 1931 XYZ color space) was one of the first color spaces to be defined mathematically. The CIE 1931 color space associates each color with tristimulus values X, Y, and Z, where the Y parameter is a measure of the lightness or brightness of the color. The chromaticity of a color is specified by the two export parameters x and y of X, Y and Z. The exported color space is specified by x, y, Y, which is called the CIE xyY color space and is widely used in practice to specify colors. The CIE 1931 color space is special because it is based on direct measurements of human color vision and serves as the basis for the definition of many other color spaces.

The sRGB color space, DCI-P3 or Adobe RGB, etc. are standard color spaces used in monitors, printers, and the Internet. Taking sRGB as an example, when outputting RGB color values in a monitor, in addition to displaying in the corresponding RGB color values, it will also display in its corresponding CIE 1931 color space. Therefore, when the display needs to be converted from one CIE 1931 color space to another CIE 1931 color space for display, the conversion can be achieved by inputting different RGB color values.

In this process, it is necessary to determine the corresponding relationship between the sRGB color space and the CIE 1931 color space. If the corresponding relationship is calculated by matrix transformation, there is a problem of low accuracy; It will consume a lot of labor cost and time cost for measurement.

SUMMARY OF THE INVENTION

The present application provides a display method, device and electronic device, which can improve the accuracy and efficiency of the display converted from one color gamut to another color gamut for display.

In a first aspect, an embodiment of the present application provides a display method, the method includes: acquiring a first RGB of a first pixel to be displayed; acquiring a third display lookup table LUT corresponding to the first application mode, the The third LUT is generated according to the fusion of the first LUT and the second LUT corresponding to the first application mode. The third LUT includes a one-to-one correspondence between the first initial RGB and the first display RGB. The first initial RGB corresponds to the initial chromaticity and Luminance parameters, the first display RGB corresponds to the chromaticity and luminance parameters of the first application mode; the first LUT includes a one-to-one mapping relationship between a plurality of first initial RGB and target RGB, and the target RGB corresponds to the specified chromaticity and luminance parameters; the second The LUT includes a one-to-one mapping relationship between a plurality of second initial RGB and display RGB. The second initial RGB corresponds to the specified luminance and chrominance parameters, and the display RGB is related to the application mode. The same second initial RGB corresponds to different application modes. The display RGB is different, and one application mode corresponds to a second LUT; the second RGB corresponding to the first RGB in the first application mode is determined according to the third LUT, and the second RGB is sent to the first display for display.

Alternatively, the display method provided by the first aspect includes: obtaining the first RGB of the first pixel to be displayed; obtaining a corresponding third lookup table LUT according to the first application mode, and the third LUT is generated by merging the first LUT and the second LUT ; wherein, different application modes correspond to different second LUTs; the third LUT includes a one-to-one mapping relationship between a plurality of first initial RGB and the first display RGB, and the first display RGB corresponds to the first application mode; the first LUT includes A one-to-one mapping relationship between a plurality of first initial RGB and target RGB, the first initial RGB corresponds to initial chromaticity and luminance parameters, and the target RGB corresponds to specified chromaticity and luminance parameters; the second LUT includes a plurality of second initial RGB and display RGB The one-to-one mapping relationship, the second initial RGB corresponds to the specified chromaticity and luminance parameters, the display RGB is related to the application mode, and the same initial RGB corresponds to different display RGB in different application modes; according to the third LUT, it is determined that the first RGB is in The corresponding second RGB in the first application mode; the second RGB is sent to the display for display.

In the embodiment of the present application, obtaining the first LUT for converting each display screen from the first initial RGB to the target RGB corresponding to the specified chromaticity and luminance parameters is to take into account the actual characteristics of each display panel and is used to describe each display panel. The color space corresponding to the display screen improves the display accuracy; in addition, the second initial RGB corresponding to the specified chromaticity and luminance parameters is obtained and converted to the second LUT of the display RGB in each application mode, and fused according to the first LUT The second LUT generates the third LUT. You can only measure and obtain the corresponding relationship between the specified chromaticity and luminance parameters and the RGB displayed in different application modes. Combined with the first LUT of each display, you can obtain the conversion of each display to The corresponding relationship of RGB in different application modes, instead of measuring the corresponding relationship of RGB when each display screen is converted to different application modes, can generate the look-up table required in different scenarios under the condition of a set of test parameters, reducing the measurement Time, improve color space conversion efficiency, and ensure conversion accuracy.

In an optional example, the method further includes: acquiring a third LUT corresponding to the second application mode, and generating the third LUT corresponding to the second application mode according to the fusion of the first LUT and the second LUT corresponding to the second application mode.

In an optional example, the method further includes: obtaining the first LUT from the memory; or receiving the first LUT from the server; or receiving the corresponding target RGB from the server according to the preset first initial RGB or obtaining the corresponding target RGB from the memory, Further, the first LUT is determined.

In the embodiment of the present application, only the target RGB is stored in the memory, and the target RGB corresponding to different first LUTs can be obtained through the preset first initial RGB, instead of repeatedly storing the first RGB in each first LUT, reducing the need for storage pressure.

In an optional example, the method further includes: acquiring a second LUT corresponding to the first application mode from a plurality of second LUTs stored in the memory; or receiving a second LUT corresponding to the first application mode from the server.

In an optional example, the method further includes: receiving an updated second LUT from the server.

In an optional example, receiving the updated second LUT from the server includes: receiving the updated second LUT from the server at a preset time or when a preset instruction is received.

In this embodiment, the second LUT is a lookup table that specifies the chrominance and luminance parameters to be converted to different application modes. When the application mode changes, an updated second LUT needs to be acquired, and the updated second LUT is acquired at a preset time. The LUT can ensure the real-time performance of acquiring the second LUT; and acquiring the updated second LUT when the preset instruction is received can ensure the practicability of acquiring the second LUT.

In an optional example, acquiring the third LUT includes: acquiring the first initial RGB in the first LUT and its corresponding target RGB; determining the real-time first display RGB obtained by mapping the target RGB according to the second LUT; An initial RGB and a first third LUT showing the mapping relationship of RGB.

In this embodiment, the first initial RGB in the first LUT is mapped to the target RGB, the target RGB corresponds to the specified chromaticity and luminance parameters, and the second initial RGB in the second LUT also corresponds to the specified chromaticity and luminance parameters. The target RGB traverses the second LUT and matches with the second initial RGB. If the matching is successful, the corresponding relationship between the first display RGB corresponding to the second initial RGB and the first initial RGB can be directly determined, and determined according to the corresponding relationship The third LUT, this process has high efficiency and low computational overhead.

In an optional example, acquiring the first LUT includes: converting the first initial RGB to obtain the intermediate RGB; performing iterative transformation on the intermediate RGB according to a preset step size to obtain the target RGB; according to the first initial RGB and the target RGB The one-to-one mapping relationship determines the first LUT.

In this embodiment, the intermediate RGB obtained according to the matrix calculation is not directly used as the target RGB, but iteratively determines the RGB for the display screen when the specified chromaticity and luminance parameters are displayed as the target RGB, which improves the generated first LUT. accuracy.

In an optional example, iteratively transforms the intermediate RGB according to the preset step size to obtain the target RGB, including: S1: transform RGB _i according to the preset step size, and obtain the corresponding chromaticity and luminance parameter change values; S2: Obtain RGB i+1 according to the preset step size, and obtain the intermediate chromaticity and luminance parameters corresponding to RGB _i ₊₁ according to the intermediate chromaticity and luminance parameters and the change values of the chrominance and luminance parameters corresponding to RGB _i ; S3: Determine RGB Whether the difference between the intermediate chrominance and brightness parameters corresponding to _i ₊₁ and the specified chrominance and brightness parameters is less than the preset threshold; is not less than the preset threshold, then set i=i+1, and repeat S1-S3 until the difference between the intermediate chromaticity and luminance parameters corresponding to RGB _i+1 and the specified chromaticity and luminance parameters is less than the preset threshold, when i When =1, RGB _i is the intermediate RGB.

In an optional example, obtaining the intermediate chromaticity and luminance parameters corresponding to RGB _i ₊₁ according to the intermediate chromaticity and luminance parameters and the change values of the chrominance and luminance parameters corresponding to RGB i, including obtaining RGB _i+ by calculating according to the following formula ₁ Corresponding intermediate chromaticity and brightness parameters:

Where xyY _i+1 is the intermediate chromaticity and brightness parameters corresponding to RGB _i+1 , xyY _i is the intermediate chromaticity and brightness parameters corresponding to RGB _i , RGB includes R parameters, G parameters and B parameters, ΔR, ΔG, ΔB are the preset step sizes of the R parameter, the G parameter and the B parameter, respectively, Δx _R , Δy _R are the chromaticity parameter changes caused by the R parameter iteration according to the preset step size, ΔY _R is the R parameter iterated according to the preset step size The resulting changes in luminance parameters, Δx _G , Δy _G are the changes in the chrominance parameters caused by the iterations of the G parameters according to the preset step size, ΔY _G is the changes in the luminance parameters caused by the iterations of the G parameters according to the preset step sizes, Δx _B , Δy _B is the change value of the chrominance parameter caused by the iteration of the B parameter according to the preset step size, and ΔY _B is the change value of the luminance parameter caused by the iteration of the B parameter according to the preset step size.

In an optional example, converting the first initial RGB to obtain the intermediate RGB includes: performing gamma transformation on the first initial RGB based on the first Gamma value to obtain the first linear rgb; A linear rgb is converted to obtain the specified chrominance and luminance parameters; the specified luminance and chrominance parameters are converted according to the second transformation matrix to obtain the second linear rgb, and the second transformation matrix is generated according to the measured luminance parameters of the first display; based on The second Gamma value performs inverse gamma transformation on the second linear rgb to obtain intermediate RGB, and the second Gamma value is determined according to the measured brightness parameter of the first display.

In a second aspect, an embodiment of the present application provides a display method, which is applied to a server. The method includes: generating a second LUT, where the second LUT includes a one-to-one mapping relationship between a plurality of second initial RGB and display RGB, and the display RGB and the application Mode related, the same second initial RGB corresponds to different display RGB in different application modes, one application mode corresponds to one second LUT; the second LUT is sent to the terminal.

In this embodiment, the server generates the second LUT, and then sends the second LUT to the terminal, so that the terminal combines the first LUT and the second LUT to generate the third LUT, because the second LUT is only related to the application mode and the specified chrominance and luminance If the parameters are related, then if the first two are determined, the second LUT can be uniformly delivered by the server to reduce the computing resource overhead of the terminal.

In an optional example, generating the second LUT includes: converting the second initial RGB to obtain display RGB, so that the display chromaticity and luminance parameters in the first application mode corresponding to the display RGB are displayed; A one-to-one mapping relationship between RGB is displayed to generate a second LUT corresponding to the first application mode.

In an optional example, the method further includes: generating a first LUT, where the first LUT includes a one-to-one mapping relationship between a plurality of first initial RGBs and target RGBs, and the target RGBs correspond to specified chromaticity and luminance parameters; sending a message to the terminal First LUT.

In the embodiment of the present application, the server generates the first LUT and sends it to the terminal, because the server can obtain the chromaticity and brightness parameters of each display screen, and generate the first LUT corresponding to each display screen, which can effectively reduce the terminal's Computing resource overhead.

In an optional example, generating the first LUT includes: converting the first initial RGB to obtain the intermediate RGB; performing iterative transformation on the intermediate RGB according to a preset step size to obtain the target RGB; according to the first initial RGB and the target RGB The one-to-one mapping relationship determines the first LUT.

In an optional example, the method further includes: generating an updated second LUT, where the updated second LUT is a second LUT corresponding to the updated first application mode; or the updated second LUT is a newly added application mode The corresponding second LUT; the updated second LUT is sent to the terminal.

In a third aspect, an embodiment of the present application provides a display processing device, the device includes a processing module, an obtaining module and a processing module, wherein the obtaining module is used to obtain the first RGB of the first pixel to be displayed; the processing module, Used to obtain the third display lookup table LUT corresponding to the first application mode, the third LUT corresponding to the first application mode is generated according to the fusion of the first LUT and the second LUT corresponding to the first application mode, and the third LUT includes a plurality of first LUTs. The one-to-one correspondence between the initial RGB and the first display RGB, the first initial RGB corresponds to the initial chromaticity and luminance parameters, and the first display RGB corresponds to the chromaticity and luminance parameters of the first application mode; the first LUT includes a plurality of first initial The one-to-one mapping relationship between RGB and the target RGB, the target RGB corresponds to the specified chromaticity and luminance parameters; the second LUT includes a one-to-one mapping relationship between a plurality of second initial RGB and the display RGB, and the second initial RGB corresponds to the initial chromaticity and luminance parameters , the display RGB is related to the application mode, the display RGB corresponding to the same second initial RGB in different application modes is different, and one application mode corresponds to a second LUT; the processing module is used to determine the first RGB according to the third LUT. An application mode corresponds to the second RGB, and the second RGB is sent to the first display for display.

In an optional example, the obtaining module is further configured to: obtain a third LUT corresponding to the second application mode, where the third LUT corresponding to the second application mode is generated by merging the first LUT and the second LUT corresponding to the second application mode .

In an optional example, the obtaining module is further configured to: obtain the first LUT from the memory; or

Receive the first LUT from the server; or receive the corresponding target RGB from the server according to the preset first initial RGB or obtain the corresponding target RGB from the memory, and then determine the first LUT.

In an optional example, the obtaining module is further configured to: obtain a second LUT corresponding to the first application mode from a plurality of second LUTs stored in the memory; or receive a second LUT corresponding to the first application mode from the server .

In an optional example, the obtaining module is further configured to: receive the updated second LUT from the server.

In an optional example, the obtaining module is specifically configured to: receive the updated second LUT from the server at a preset time or when a preset instruction is received.

In an optional example, the processing module is specifically configured to: obtain the first initial RGB in the first LUT and its corresponding target RGB; determine the real-time first display RGB obtained by mapping the target RGB according to the second LUT; An initial RGB and a first third LUT showing the mapping relationship of RGB.

In an optional example, the processing module is specifically configured to: convert the first initial RGB to obtain the intermediate RGB; perform iterative transformation on the intermediate RGB according to a preset step size to obtain the target RGB; according to the first initial RGB and the target RGB The one-to-one mapping relationship determines the first LUT.

In an optional example, the processing module is specifically used to: S1: transform RGBi according to a preset step size, and obtain corresponding change values of chrominance and luminance parameters; S2: obtain RGBi+1 according to the preset step size, according to Obtain the intermediate chrominance and brightness parameters corresponding to RGBi and the change values of the chrominance and brightness parameters to obtain the intermediate chromaticity and brightness parameters corresponding to RGBi+1; S3: Determine the intermediate chrominance and brightness parameters corresponding to RGBi+1 and the specified chromaticity and brightness Whether the difference between the parameters is less than the preset threshold; if the difference between the intermediate chrominance and brightness parameters corresponding to RGBi+1 and the specified chrominance and brightness parameters is not less than the preset threshold, set i=i+1, and repeat S1 -S3, until the difference between the intermediate chrominance and brightness parameters corresponding to RGBi+1 and the specified chrominance and brightness parameters is less than the preset threshold, when i=1, RGBi is the intermediate RGB.

In an optional example, the processing module is specifically configured to: calculate and obtain intermediate chromaticity and luminance parameters corresponding to RGB _i+1 according to the following formula:

In an optional example, the processing module is specifically configured to: perform gamma transformation on the first initial RGB based on the first Gamma value to obtain the first linear rgb; convert the first linear rgb according to the first transformation matrix to obtain the specified Chroma and luminance parameters; convert the specified luminance and chrominance parameters according to the second transformation matrix to obtain a second linear rgb, and the second transformation matrix is generated according to the measured brightness parameters of the first display; based on the second Gamma value, the second linear rgb performs inverse gamma transformation to obtain intermediate RGB, and the second Gamma value is determined according to the measured brightness parameter of the first display.

In a fourth aspect, an embodiment of the present application provides an apparatus for display processing, the apparatus includes a processor and an interface circuit, the interface circuit is configured to receive code instructions and transmit them to the processor, and the processor is configured to run all The code instructions are used to perform the method according to any one of the first aspects, or to perform the method according to any one of the second aspects.

In a fifth aspect, an embodiment of the present application provides an apparatus for display processing, the apparatus includes a processor, a transceiver, a memory, and computer-executable instructions stored in the memory and executable on the processor, when The computer-executable instructions, when executed, cause the communication apparatus to perform the method of any one of the first aspect, or to perform the method of any one of the second aspect.

In a sixth aspect, a computer-readable storage medium is provided, and program instructions are stored in the computer-readable storage medium. When the program instructions are executed on a computer or a processor, the computer or the processor can perform any of the above-mentioned aspects. Methods.

In a seventh aspect, there is provided a computer program product comprising instructions which, when run on a computer or processor, enable the computer or processor to perform the method of any of the above aspects.

In an eighth aspect, an electronic device is provided, including the above-mentioned apparatus for display processing.

Wherein, for the technical effect brought by any one of the design methods in the second aspect to the eighth aspect, reference may be made to the technical effects brought by the different design methods in the above-mentioned first aspect, which will not be repeated here.

Description of drawings

FIG. 1 is a schematic structural diagram of an exemplary apparatus provided by an embodiment of the present application;

2 is a schematic diagram of a display screen color value conversion scene provided by an embodiment of the present application;

3 is a schematic diagram of a color value conversion process of a display screen provided by an embodiment of the present application;

4A is a schematic diagram of the architecture of a color gamut correction system corresponding to an embodiment of the present application;

FIG. 4B is a flowchart of a display method provided by an embodiment of the present application;

4C is a schematic diagram of a process of applying a third LUT provided by an embodiment of the present application;

4D is a schematic schematic diagram of a first LUT and a second LUT fused to generate a third LUT according to an embodiment of the present application;

4E is a flowchart of determining target RGB provided by an embodiment of the present application;

4F is a schematic diagram of a fusion process of a first LUT and a second LUT provided by an embodiment of the application;

FIG. 5 is a structural block diagram of an apparatus for display processing provided by an embodiment of the present application;

FIG. 6 is a schematic diagram of a hardware structure of an apparatus for display processing provided by an embodiment of the present application.

detailed description

The technical solutions in the embodiments of the present application will be described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments.

The term "and/or" in this article is only an association relationship to describe the associated objects, indicating that there can be three kinds of relationships, for example, A and/or B, it can mean that A exists alone, A and B exist at the same time, and A and B exist independently. B these three cases. In the embodiments of the present application, words such as "exemplary" or "for example" are used to represent examples, illustrations or illustrations. Any embodiments or designs described in the embodiments of the present application as "exemplary" or "such as" should not be construed as preferred or advantageous over other embodiments or designs. Rather, the use of words such as "exemplary" or "such as" is intended to present the related concepts in a specific manner. In the description of the embodiments of the present application, unless otherwise specified, the meaning of "plurality" refers to two or more. For example, multiple processing units refers to two or more processing units; multiple systems refers to two or more systems. Hereinafter, the terms "first", "second", etc. are only used for descriptive purposes, and should not be understood as indicating or implying relative importance or implying the number of indicated technical features. Thus, a feature defined as "first", "second", etc., may expressly or implicitly include one or more of that feature. In the description of this application, unless stated otherwise, "plurality" means two or more.

FIG. 1 is a schematic structural diagram of an exemplary apparatus provided by an embodiment of the present application. As shown in FIG. 1 , the device 01 includes: a processor 11 , a radio frequency (RF) circuit 12 , a power supply 13 , a memory 14 , an input unit 15 , a display unit 16 , an audio circuit 17 and other components. Those skilled in the art can understand that the structure of the device shown in FIG. 1 does not constitute a limitation to the device, and the device may include more or less components than those shown in FIG. 1 , or may be combined as shown in FIG. 1 . Some of the components shown may alternatively be arranged differently from the components shown in FIG. 1 .

The processor 11 is the control center of the device, using various interfaces and lines to connect various parts of the entire device, by running or executing the software programs and/or modules stored in the memory 14, and calling the data stored in the memory 14, Execute various functions of the device and process data to monitor the device as a whole. Optionally, the processor 11 may include one or more processing units; preferably, the processor 11 may integrate an application processor and a modem processor, wherein the application processor mainly processes the operating system, user interface, and application programs, etc. , the modem processor mainly deals with wireless communication. It can be understood that, the above-mentioned modulation and demodulation processor may not be integrated into the processor 11 .

The RF circuit 12 can be used for receiving and sending signals during transmission and reception of information or during a call. In particular, after receiving the downlink information of the base station, it is processed by the processor 11; in addition, the uplink data is sent to the base station. Typically, RF circuits include, but are not limited to, antennas, at least one amplifier, transceivers, couplers, low noise amplifiers (LNAs), duplexers, and the like. In addition, the RF circuit 12 may also communicate with the network and other devices via wireless communication. Wireless communication can use any communication standard or protocol, including but not limited to global system of mobile communication (GSM), general packet radio service (GPRS), code division multiple access (code division multiple) access, CDMA), wideband code division multiple access (wideband code division multiple access, WCDMA), long term evolution (long term evolution, LTE), email, short message service (short messaging service, SMS) and so on.

The device includes a power supply 13 (such as a battery) for supplying power to various components. Optionally, the power supply can be logically connected to the processor 11 through a power management system, so as to manage charging, discharging, and power consumption management functions through the power management system.

The memory 14 can be used to store software programs and modules, and the processor 11 executes various functional applications and data processing of the device by running the software programs and modules stored in the memory 14 . The memory 14 may mainly include a stored program area and a stored data area, wherein the stored program area may store an operating system, an application program (such as a sound playback function, an image playback function, etc.) required for at least one function, and the like; Data created by the use of the mobile phone (such as audio data, image data, phone book, etc.), etc. Additionally, memory 14 may include high-speed random access memory, and may also include non-volatile memory, such as at least one magnetic disk storage device, flash memory device, or other volatile solid state storage device.

The input unit 15 may be used to receive input numerical or character information, and to generate key signal input related to user settings and function control of the device. Specifically, the input unit 15 may include a touch screen 151 and other input devices 152. The touch screen 151, also known as a touch panel, can collect the user's touch operations on or near the touch screen (such as the user's operations on or near the touch screen 151 using a finger, a stylus, or any suitable object or accessory), and according to the The preset program drives the corresponding connection device. Optionally, the touch screen 151 may include two parts, a touch detection device and a touch controller. Among them, the touch detection device detects the user's touch orientation, detects the signal brought by the touch operation, and transmits the signal to the touch controller; the touch controller receives the touch information from the touch detection device, converts it into contact coordinates, and then sends it to the touch controller. To the processor 11, and can receive the command sent by the processor 11 and execute it. In addition, the touch screen 151 may be implemented in various types such as resistive, capacitive, infrared, and surface acoustic waves. Other input devices 152 may include, but are not limited to, one or more of a physical keyboard, function keys (such as volume control keys, power switch keys, etc.), trackballs, mice, joysticks, and the like.

The display unit 16 may be used to display information input by the user or information provided to the user and various menus of the device. The display unit 16 may include a display panel 161, and in the present application, the display panel 161 may be configured with an AMOLED display screen. Further, the touch screen 151 can cover the display panel 161. When the touch screen 151 detects a touch operation on or near the touch screen 151, it transmits it to the processor 11 to determine the type of the touch event, and then the processor 11 displays the touch event according to the type of the touch event. Corresponding visual outputs are provided on panel 161 . Although in FIG. 1, the touch screen 151 and the display panel 161 are used as two independent components to realize the input and output functions of the device, in some embodiments, the touch screen 151 and the display panel 161 can be integrated to realize the input of the device and output functions.

Audio circuit 17, speaker 171 and microphone 172 are used to provide an audio interface between the user and the device. The audio circuit 17 can transmit the received audio data converted electrical signal to the speaker 171, and the speaker 171 converts it into a sound signal for output; on the other hand, the microphone 172 converts the collected sound signal into an electrical signal, which is converted by the audio circuit 17 Upon receipt, it is converted to audio data, which is then output to RF circuit 12 for transmission to, for example, another device, or to memory 14 for further processing.

Optionally, the device shown in FIG. 1 may further include various sensors. For example, a gyroscope sensor, a hygrometer sensor, an infrared sensor, a magnetometer sensor, etc., will not be repeated here. Optionally, the apparatus shown in FIG. 1 may further include a wireless fidelity (wireless fidelity, WiFi) module, a Bluetooth module, etc., which will not be repeated here.

It can be understood that, in this embodiment of the present application, an electronic device (for example, the apparatus shown in FIG. 1 above) may execute some or all of the steps in the embodiment of the present application, these steps or operations are only examples, and the embodiment of the present application may also be executed Other operations or variations of various operations. In addition, various steps may be performed in different orders presented in the embodiments of the present application, and may not be required to perform all the operations in the embodiments of the present application. Each embodiment of the present application may be implemented independently or in any combination, which is not limited in this application.

To facilitate understanding of the embodiments of the present application, some concepts or terms involved in the embodiments of the present application are explained.

(1) Gamma correction

Gamma correction is a method of non-linear tonal editing of the image, which can detect the dark part and the light part in the image signal, and increase the ratio of the two, thereby improving the contrast effect of the image. The photoelectric conversion characteristics of current display screens, photographic films, and many electronic cameras can be nonlinear. The relationship between the output and input of these nonlinear components can be represented by a power function, ie: output = (input) ^γ .

The non-linear transformation of the color value output by the device is due to the fact that the human visual system is not linear, and humans perceive visual stimuli through comparison. The outside world strengthens the stimulus in a certain proportion, and for people, this stimulus increases evenly. Therefore, for human perception, the physical quantity that increases in a proportional sequence is uniform. In order to display the input color according to the laws of human vision, it is necessary to convert the linear color value into a nonlinear color value through the nonlinear transformation in the form of the above power function. The value γ of gamma may be determined according to the photoelectric conversion curve of the color space.

(2) Color space

Color can be the different perceptions of the eyes for light of different frequencies, or it can represent the light of different frequencies that exists objectively. A color space is a range of colors defined by a coordinate system that people have established to represent colors. A color gamut, together with a color model, defines a color space. Among them, the color model is an abstract mathematical model that represents color with a set of color components. The color model may include, for example, three primary color mode (red green blue, RGB), printing four-color mode (cyan magenta yellow key plate, CMYK). Color gamut refers to the totality of colors that a system can produce. Illustratively, Adobe RGB and sRGB are two different color spaces based on the RGB model.

Each device such as a monitor or printer has its own color space and can only produce colors within its gamut. When moving an image from one device to another, the color of the image may change on different devices as each device converts and displays RGB or CMYK according to its own color space.

Several commonly used color spaces are described below.

①CIE 1931 color space

The CIE 1931 color space (also known as the CIE 1931 XYZ color space) was one of the first color spaces to be defined mathematically. The CIE XYZ color space is directly measured based on human color vision and can serve as the basis for the definition of other color spaces. The Y parameter used by the CIE XYZ color space is the lightness or lightness of the color. The chromaticity of a color is determined using parameters x and y, and the relationship between chromaticity x, y and tristimulus values X, Y, and Z is:

A color can be determined by the parameters x, y, Y. For a display screen, the chromaticity coordinates x, y and the luminance value Y can be measured using a color analyzer. Among them, X and Z in tristimulus values can be calculated from chromaticity coordinates x, y and luminance Y:

②sRGB color space

The sRGB (standard Red Green Blue) color space is a standard RGB color space developed by HP and Microsoft in 1996 for monitors, printers and the Internet. It provides a standard way to define color, so that various computer peripherals and application software, such as display, printing and scanning, have a common language for color. The sRGB color space is based on independent color coordinates, which enables colors to correspond to the same color coordinate system in the transmission of different devices, without being affected by the different color coordinates of these devices. However, the color gamut space of sRGB is relatively small. sRGB defines the colors of the three primary colors of red, green and blue, where the color value of one of the three primary colors takes the maximum value, and the color corresponding to the color value of the other two colors is zero, which represents the one color. Exemplarily, in the three primary colors of red, green and blue, the color values R, G and B are all 0-255, then when the values of R and G are all zero, the corresponding value of B is 255. Color means blue.

If the two monochromatic lights are combined into one test color light, the value of the three primary colors perceived by the observer is the sum of the three primary color values of the two monochromatic lights observed separately.

In other words, if beam 1 and beam 2 are monochromatic light, and {R1, G1, B1}, {R2, B2, G2} are the three primary color values of the observer's perception of beam 1 and beam 2, respectively, when these two beams When combined, the three primary color values perceived by the observer are {R,G,B}, where:

R=R1+R2

G=G1+G2

B=B1+B2

Beam 1 {R1, G1, B1} and beam 2 {R2, G2, B2} are represented by the CIE1931 color space, and the corresponding tristimulus values are {X1, Y1, Z1} and {X2, Y2, Z2} respectively, then the observation The tristimulus values {X, Y, Z} corresponding to the three primary colors {R, G, B} felt by the user are:

X=X1+X2

Y=Y1+Y2

Z=Z1+Z2

③ Color space conversion

Conversion between different color spaces is possible. The following uses CIE1931 color space and sRGB color space as examples to introduce color space conversion.

Calculating the three primary colors in sRGB from the CIE xyY coordinate system first requires transforming it into the CIE XYZ three-valued mode. That is to use formula (3) and formula (4) to determine X, Z to obtain three values X, Y and Z in the CIE 1931 color space. Then use the transformation matrix to calculate the linear R, G and B values:

sRGB is a reflection of the color values displayed by a typical monitor with a real-world gamma of 2.2, so use the following transformation formula to convert linear values to sRGB:

(3) Color value transformation of the display screen

When the display screen is displayed, due to the different color gamuts corresponding to different display screens, when the same RGB color value is input, the human eye perceives the same X, Y, and Y tristimulus values are also different. If people want to feel the same X, Y, and Y tristimulus values, the color gamut of the display screen needs to be converted, and the corresponding color value of the input sRGB color space also needs to be corrected.

Referring to FIG. 2, FIG. 2 is a schematic diagram of a display screen color value conversion scene provided by an embodiment of the application. As shown in FIG. 2, the input image fig.1 is input to the display screen 201. When the display screen 201 is in the initial color gamut , take a target pixel in fig.1 as an example, the corresponding color value of the target pixel in the initial color gamut display is the first RGB, and the corresponding XYZ stimulus value is the initial XYZ stimulus value. Color gamut correction is performed on the display screen 201 so that the color value corresponding to the target pixel is the second RGB, and the corresponding XYZ stimulus value is the target XYZ stimulus value.

The process of converting the display screen from the first RGB to the second RGB for display in FIG. 1 specifically includes the following steps:

Step 1: Perform linear transformation on the received color value of the standard color gamut image.

What the display screen displays in the initial color gamut is a standard color gamut image, which is also described by taking a target pixel as an example, and the color value of the target pixel is the first RGB. Since in the first RGB: the red component value R0, the green component value G0 and the blue component value B0 are all nonlinear, it is necessary to convert the nonlinear color values into linear color values before performing color value transformation. Please refer to FIG. 3. FIG. 3 is a schematic diagram of a color value conversion process of a display screen provided by an embodiment of the present application. The first RGB can be converted from a nonlinear value to a linear value through gamma transformation. For example, a first gamma (gamma) look-up table is stored, the first gamma look-up table includes the mapping relationship between nonlinear RGB and its corresponding linear rbg, and the first gamma look-up table is used to realize the conversion of nonlinear color values to linear color value. Specifically, gamma may be 2.2, and the mapping relationship of the first gamma lookup table may be to map the input red component value R0, green component value G0, and blue component value B0 to red component value R1, green component value G1, and blue component value in turn The color component value B1, wherein the red component value R1, the green component value G1 and the blue component value B1 are referred to as the first linear rgb. Among them, the conversion of the input nonlinear RGB to the first linear RGB is realized by the following formula:

In the first gamma lookup table, a nonlinear color value range may correspond to a linear color value. For example, the nonlinear color values in the range of (R0-ΔR, R0+ΔR) all correspond to R1 in the first gamma lookup table. For example, please refer to Table 1. Table 1 is an example of a first gamma lookup table provided by the embodiment of the present application.

Table 1 First gamma lookup table

As shown in Table 1, the values of the color values R0, G0 and B0 may all be 0-2 ¹⁰ , and R0 in a certain range corresponds to the same R1 in the first gamma lookup table. It can be normalized according to a value selected in the corresponding range of R0, so that the obtained values are all between 0 and 1, and then the gamma calculation is performed, and the 10-bit value is output, which is R1. For example, when R0 is 0-31, the corresponding R1 is (15/1023)2.2*1023. For R0 whose values fall in the range of 32-63, 32-63, ^64-95 ... (79/1023) ^2.2 *1023...(1007/1023) ^2.2 *1023 etc.

In addition, in the first gamma lookup table, a nonlinear color value may also correspond to a linear color value. The linear color value corresponding to the non-linear color value not stored in the first gamma lookup table may be determined by interpolation of the linear color value corresponding to the nonlinear color value stored in the lookup table. For example, please refer to Table 2, which is another example of the first gamma lookup table provided by the embodiment of the present application.

Table 2 First gamma lookup table

R0/G0/B0R0/G0/B0	00	3232	6464	……...	10231023
R1/G1/B1R1/G1/B1	00	(32/1023) ^2.21023 (32/1023) ^2.2 1023	(64/1023) ^2.21023 (64/1023) ^2.2 1023	……...	(1023/1023) ^2.21023 (1023/1023) ^2.2 1023

As shown in Table 2, the color values R0, G0 and B0 can all be 0-2 ¹⁰ . Taking R0 as an example, the value of R0 is 0, 32, 64...1023, which corresponds to the first gamma lookup table The value of R1 is 0, (32/1023) ^2.2 *1023, (64/1023)2.2*1023...(1023/1023)2.2*1023. In addition, in order to avoid loss of precision, 12bit R1 value can also be output. For example, when R0 is 32, the corresponding R1 can be (32/1023) ^2.2 *4095. When R0 takes a value other than 0, 32, 64...1023, the corresponding R1 value is determined by interpolating these known R1 values in the first gamma lookup table. The value of R1 corresponding to when the value of R0 is 25 is determined by interpolation according to the value of R1 corresponding to when the value of R0 is 0 and 32 in turn. In the embodiment of the present application, the specific algorithm used by the interpolation method is not limited, and may be a linear interpolation method, a Lagrangian interpolation method, or the like, or other interpolation methods may be used.

It can be understood that the above example of the first gamma lookup table is only used to explain the embodiment of the present application, and should not be construed as a limitation. The examples of this application take a gamma of 2.2 as an example to introduce the conversion between nonlinear color values and linear color values. The example should not constitute a limitation. The specific gamma value can also be determined according to the photoelectric conversion curve of the color space. The embodiment of the present application does not limit the specific gamma value.

Step 2: Perform color gamut conversion to obtain the color value of the display screen.

(1) Color gamut conversion by conversion matrix

After obtaining the first linear rgb corresponding to the first RGB through the first gamma lookup table, color gamut conversion can be performed, that is, the initial XYZ stimulus value of the display screen is converted to the target XYZ stimulus value, and the first linear rgb is converted to the second Linear rgb, the second linear rgb is the linear color value corresponding to the second RGB. Target XYZ stimulus values can be expressed as: Xt, Yt and Zt.

Since the color gamut of different display screens is different, in order for the eyes to feel the same target XYZ stimulus value, the corresponding input RGB color value needs to be corrected. This process requires both color space conversion and display color gamut correction. The specific principles are as follows:

In formula (8)

is the target color value to which the display screen needs to be converted, that is, the second linear rgb corresponding to the second RGB.

It can be a conversion matrix from sRGB color space to 1931 color space, and specifically can be an inverse matrix of the 3×3 conversion matrix in formula (5).

Among them, X _R , Y _R and Z _R are the corresponding tristimulus values when the red color value R of the display screen takes the maximum value, and X _G , Y _G and Z _G are the three corresponding tristimulus values when the green color value G of the display screen takes the maximum value. Color stimulus value, X _B , Y _B and Z _B are the corresponding tristimulus values when the blue color value B of the display screen takes the maximum value. Exemplarily, the color values R, G and B of the display screen are all 0-255, then X _R , Y _R and Z _R are the corresponding tristimulus values when the red color value R of the display screen is 255, X R _G , Y _G and Z _G are the corresponding tristimulus values when the green color value G of the display screen is 255, X _B , Y _B and Z _B are the corresponding tristimulus values when the display screen blue color value B is 255 .

Deformation of formula (8) can be obtained:

In formula (9), let

That is to get:

can be stored

The 3×3 conversion matrix is used to convert the linear color values R1 , G1 and B1 output by the first gamma lookup table into the linear color values R _pannel , G _pannel and B _pannel on the display color gamut of the display screen.

(2) Color gamut conversion by look-up table

Alternatively, the color gamut conversion on the display can also be performed directly by storing the color value lookup table. That is, when the first RGB is determined, the corresponding second RGB is found through the color value look-up table, so that the display screen is displayed under the target XYZ stimulus value, and the color gamut conversion is completed. The mapping relationship of the color value look-up table may be obtained by measurement, and a three-dimensional color value look-up table is established by using the known target color gamut and the color values on the display screen corresponding to the color gamut measured by the color analyzer. The three dimensions are R, G, and B, respectively. In the color value lookup table, the same set of values of the initial color values R _in , G _in and B _in can uniquely correspond to a set of display target color values R _out , G according to the three dimensions The values of _out and B _out . When the color value lookup table looks for the unsaved R1, G1 and B1 values, find the position of the input linear color value in the three dimensions in the color value lookup table, and determine the color value of the display screen by interpolation method, For the description of the interpolation method, reference may be made to the specific description in step 1, and details are not repeated here.

Optionally, the color value RGB stored in the color value lookup table may be a linear value or a non-linear value.

Step 3: Perform nonlinear conversion on the linear color value.

The above R _pannel , G _pannel , and B _pannel obtained by formula (10) are linear color values on the display color gamut of the display screen. In order to ensure that the color is displayed according to the laws of human vision, it needs to undergo non-linear transformation. The nonlinear transformation can be implemented by a look-up table similar to the linear transformation in step one. Specifically, a second gamma lookup table can be stored, the second gamma lookup table includes the correspondence between linear rgb and its corresponding nonlinear RGB, and the second gamma lookup table is used to realize the linear color value on the display color gamut of the display screen Convert to non-linear color values. Specifically, the gamma may be 2.2, and the mapping relationship of the second gamma lookup table may be to map the input red component value R _pannel , green component value G _pannel and blue component value B _pannel to the red component value R2 , the green component value R2 and the green component value in turn. G2 and blue component value B2. in:

In the second gamma lookup table, a linear color value range may correspond to a non-linear color value. For example, linear color values in the range of (R _{pannel -ΔR1} , R _pannel +ΔR1) all correspond to R2 in the first gamma lookup table. In addition, in the second gamma lookup table, a linear color value may also correspond to a nonlinear color value. The nonlinear color value value corresponding to the unsaved linear color value value in the second gamma lookup table may be determined by an interpolation method. For the description of the interpolation method, reference may be made to the specific description in step 1, which will not be repeated here.

Step 4: Display the display screen according to the non-linear color value obtained by conversion.

The second RGB corresponding to when the display screen is converted to the target XYZ stimulus value is obtained, specifically the non-linear red component value R2, green component value G2 and blue component value B2, and the display screen displays according to the corresponding color values.

The display screens involved in the embodiments of the present application may be LED display screens, and may specifically include various types of organic light-emitting diode (organic light-emitting diode, OLED) display screens, such as AMOLED display screens, passive matrix organic light emitting diodes (passive matrix organic light emitting diodes) matrix organic light-emitting diodes, PM-OLED) display screen, may also include other types of LEDs, and may also include future types of displays, which are not limited in the embodiments of the present application.

In the above-mentioned display color gamut conversion process, when the color value is transformed by the transformation matrix, the white brightness of the display is generally required to be corrected to gamma 2.2 to meet the human eye's perception of brightness. However, there is crosstalk between the RGB pixels of the display. As a result, when the gamma curve of the white brightness is corrected to 2.2, the brightness corresponding to the three components of R, G, and B may not conform to the gamma 2.2, and the gammas corresponding to displays of different technological levels are different. , so the linear domain to nonlinear domain conversion cannot be accurately performed, thus affecting the color accuracy. At the same time, since the light-emitting wavelength of the LED is affected by the driving voltage, the chromaticity coordinates x and y of the RGB will change with the brightness, especially for the OLED with active light emission or the LCD with the LED as the backlight, especially if the brightness is low. In the case of , the amount of change is relatively large, and a fixed 3x3 matrix cannot well correct the color gamut of the display screen to the standard color gamut, thus affecting the color accuracy.

The color value transformation through the color value lookup table is to directly map the RGB color value of the standard color gamut image as the input RGB component to the RGB component output by the display. In theory, if the color value lookup table is large enough, the input RGB can be mapped one by one. RGB components to the monitor output, allowing the monitor to display accurate colors.

In practical applications, it is impossible to map each RGB component one by one, so a color value lookup table of 5x5x5, 9x9x9 or even 17x17x17 is used, and the position of the corresponding color value lookup table is searched according to the input RGB, and then the corresponding output is obtained by interpolation calculation. value.

Before generating the color value lookup table, each node in the table needs to be corrected to display accurate colors. The calibration process is as follows: The chromaticity and luminance parameters (ie, the xyY parameters, which are used to describe the color of the pixel, are used to describe the color of the pixel, and have a function with the tristimulus value XYZ perceived by the human eye) when a certain RGB color value is input to the display screen through a color analyzer. relationship), the computer performs the calculation and then writes it into the storage of the mobile phone. The more information tested, the more accurate the color correction will be. However, too many sampling tests will affect the actual display production capacity. For example, it takes 200-500ms to measure a color on the display. Usually, more than 17x17x17 colors need to be measured to achieve accurate color gamut correction of the display. One hour.

At the same time, for different display scenarios, the display needs to be calibrated to different color gamuts, and usually needs to use different color value lookup tables. In order to ensure the display consistency in different scenarios, it is necessary to perform color correction for different scenarios, so as the usage scenarios increase, the correction time will be longer.

Based on the above description, an embodiment of the present application provides a display method to solve the above-mentioned problems of low display color accuracy and low color gamut conversion efficiency. Firstly, the system architecture of this method is introduced. Please refer to FIG. 4A . FIG. 4A is a schematic diagram of the architecture of a color gamut correction system corresponding to an embodiment of the present application. As shown in FIG. 4A , the system architecture 40 includes various functional modules 401 , such as a user interface, an image module, and a video module. , a shooting module, etc.; and then includes a graphics processor (graphics processing unit, GPU) 402 capable of image processing, and includes a display subsystem 403 for determining display colors, and a display screen 404 for displaying colors. The display subsystem 403 further includes various sub-modules for determining display colors, such as a scaling module, a color space conversion module, a high-dynamic range (high-dynamic range, HDR) image module, a color module, and the like. The color module 4036 is used to generate a color value lookup table, so that the initial RGB displayed in the current color gamut of the display screen can find the corresponding display RGB according to the color value lookup table, so that when the display screen is displayed by displaying RGB, the corresponding XYZ The tristimulus value is the same as the standard color gamut, that is, the display is corrected to the standard color gamut. FIG. 4A may be fully deployed in the electronic device described in FIG. 1 , or partially deployed in the electronic device described in FIG. 1 , so as to implement the display method described in the embodiments of the present application.

Please refer to FIG. 4B . FIG. 4B is a flowchart of a display method provided by an embodiment of the present application. As shown in FIG. 4B , the method includes the following steps:

501. Obtain the first RGB of the first pixel to be displayed.

In some cases, a terminal device may be referred to as a terminal (terminal) for short, also referred to as a user equipment (user equipment, UE), or a subscriber unit (subscriber unit, SU), which may be specifically a mobile phone (mobile phone), Tablet computers, laptop computers, wearable devices (such as smart watches, smart bracelets, smart helmets, smart glasses), and other devices with wireless access capabilities, such as smart cars, are Internet of Things (IOT) devices, including various smart home devices (such as smart meters and smart home appliances) and smart city devices (such as security or monitoring devices, smart road traffic facilities), etc. In the case where the terminal device includes a display screen, the image can be displayed according to its own color gamut, screen material or other parameters. For a specific image, its corresponding color can be described by the RGB color value of each pixel. Therefore, after obtaining the input image that needs to be displayed on the first display screen, first obtain the corresponding color value of each pixel of the input image. The first RGB, used to describe the input image.

502. Obtain the third display lookup table LUT corresponding to the first application mode, the third LUT corresponding to the first application mode is generated according to the fusion of the first LUT and the second LUT corresponding to the first application mode, and the third LUT corresponding to the first application mode is merged and generated. The LUT includes a one-to-one correspondence between a plurality of initial RGB and the first display RGB, the initial RGB corresponds to the initial chromaticity and luminance parameters, and the first display RGB corresponds to the chromaticity and luminance parameters of the first application mode; The first LUT includes a one-to-one mapping relationship between a plurality of initial RGB and target RGB, and the target RGB corresponds to specified chromaticity and luminance parameters; the second LUT includes a one-to-one mapping relationship between a plurality of initial RGB and display RGB, so the The display RGB is related to the application mode, the same initial RGB corresponds to different display RGB in different application modes, and one application mode corresponds to one of the second LUTs.

503. Determine, according to the third LUT, a second RGB corresponding to the first RGB in the first application mode, and send the second RGB to a first display for display.

Usually, the application mode includes multiple modes divided by product, such as mobile phone mode, tablet mode, TV mode, etc.; or multiple modes divided by different application scenarios, such as divided according to energy consumption mode, which can include conventional mode and power saving mode, etc.; according to the application content, it can include web page mode, video mode, image mode, etc. Different application modes have different corresponding color gamuts, that is, for the same input image, the RGB color values and XYZ tristimulus values in each application mode are also different.

In this embodiment of the present application, after acquiring the pixels to be displayed (which may be images or videos), to convert them to color gamuts in different application modes for display, you can generate the corresponding first pixel in each application mode by generating The third is to display a look up table (LUT), and after determining the first application mode corresponding to the display screen, input the first RGB of the input image into the third LUT corresponding to the first application mode, and obtain the corresponding The second RGB, so that when the display screen is displayed by the second RGB, the display in the color gamut corresponding to the first application mode is achieved.

Before applying the mapping relationship of the third LUT to determine the second RGB corresponding to each input image for display, the third LUT needs to be generated. The third LUT includes a one-to-one correspondence between a plurality of first initial RGBs and first display RGBs. The first initial RGB is the color value corresponding to when the display screen is displayed in the current color gamut. Under normal circumstances, each display screen can be displayed in the interval of R, G and B values respectively 0-255 (in decimal). Then the first initial RGB can be some typical sampled RGB, such as the value obtained by dividing 0-255 into 17 equal parts, then the initial RGB can be (0,0,16), (0,32,16), (16 , 16, 48), (16, 64, 16), (240, 0, 0)...(255, 255, 255) and so on. The first display RGB is the color value to which the initial RGB corresponds when the display screen is converted to the color gamut in the first application mode. The content in the third LUT can be shown in the following table:

Table 3 Third LUT

第一初始RGBfirst initial RGB	第一显示RGBfirst display RGB
(0,,0,16)(0,,0,16)	(0,0,10)(0,0,10)
(0,32,32)(0,32,32)	(0,25,25)(0,25,25)
……	……
(255,255,255)(255,255,255)	(250,250,250)(250,250,250)

For example, the first initial RGB of the input image is (255, 255, 255), that is, the red component value, the green component value and the blue component value are all 255, which is a white image. In the first application mode, all white images need to be displayed at a lower brightness, that is, mapped to display RGB (250, 250, 250) for display.

For each display on the production line, its corresponding third LUT in each application mode needs to be determined. In order to determine the corresponding display RGB of the input image on each display screen and each application mode. For details, please refer to FIG. 4C. FIG. 4C is a schematic diagram of a process of applying a third LUT provided by an embodiment of the present application. As shown in FIG. 4C, the same input image can be input into different display screens, and different display screens can display The difference between brightness and color, the transmittance of LCD, and the material of OLED make each display screen feel the same chromaticity and brightness, and the corresponding RGB display will be different. On the other hand, the same display screen can be used in multiple application modes, that is, the same display screen can be displayed in different chromaticity and brightness, and the corresponding display RGB will be different. Therefore, after the input image is input to the display screen, the display RGB of the corresponding output image is related to the display screen on the one hand, and the application mode of the display screen on the other hand, and can be generated and applied according to each application mode of each display screen. A third LUT.

According to the foregoing description, for each display screen, the corresponding display RGB of the display screen in each application mode can be measured multiple times to directly generate the third LUT in this mode, but this will lead to the problem of low generation efficiency. Or calculate the corresponding display RGB of each display screen in different application modes according to the matrix transformation, and then generate the third LUT, which will cause the acquired display RGB to be inaccurate, which will lead to inaccurate chromaticity and brightness parameters displayed on the display screen. The problem. In this embodiment of the present application, the third LUT is generated by fusing the first LUT and the second LUT. For the specific process, please refer to FIG. 4D . FIG. 4D is a schematic diagram of the principle of generating a third LUT by fusing a first LUT and a second LUT according to an embodiment of the present application. As shown in FIG. 4D , for any first display screen, the When a display screen is converted from the initial color gamut to the specified color gamut of the designated display screen, the corresponding color value is converted from the first initial RGB to the target RGB, and the corresponding color value of the display screen is generated according to the one-to-one mapping relationship between the first initial RGB and the target RGB. The first LUT; when the specified display screen is converted from the specified color gamut to the display color gamut corresponding to each application mode, its corresponding output RGB is converted from the second initial RGB to the display RGB, and the display RGB is related to the application mode. Two initial RGBs correspond to different display RGBs in different application modes, and one application mode corresponds to one second LUT. Each second LUT includes a one-to-one mapping relationship between multiple second initial RGB and display RGB, and the second initial RGB in the second LUT is also some typical RGB values, such as the values obtained by dividing 0-255 into 17 equal parts, Then the second initial RGB can be (0,0,16), (0,32,16), (16,16,48), (16,64,16), (240,0,0)...(255,255,255 )Wait. In different application modes, the same second initial RGB value will be mapped to different display RGBs. For example, in the second LUT corresponding to the night eye protection mode, when the second initial RGB is (255, 255, 255), the display mapped to The RGB may be (150, 150, 150); in the second LUT corresponding to the outdoor mode, when the second initial RGB is (255, 255, 255), the mapped display RGB may be (250, 250, 250). Finally, the first LUT and the second LUT are merged to generate a third LUT, and the application mode corresponding to the third LUT is the application mode corresponding to the second LUT.

Specifically, for each display screen, inputting an RGB will have its corresponding XYZ tristimulus value perceived by the human eye, and its derived parameters x, y, and Y are used to characterize the brightness and color corresponding to the stimulus value. In the embodiments of the present application, the x, y, and Y parameters are expressed as chromaticity and luminance parameters corresponding to RGB. The initial color gamut of each display screen (can be factory color gamut, default color gamut, etc.) can be characterized by the initial RGB and the initial chromaticity and luminance parameters corresponding to the initial RGB. The conversion relationship between RGB and XYZ stimulus values can be based on The aforementioned formula (5) and formula (6) are calculated and obtained, and the functional relationship between XYZ stimulus value and chromaticity and luminance parameters can be determined according to the aforementioned formulas (1) to (4), so the conversion relationship between RGB and chromaticity and luminance parameters can be derived.

For the first display screen and the designated display screen, the RGB color value, brightness and chromaticity parameters, and the corresponding relationship of the color gamut are shown in the following table:

Table 4 Color gamut relationship between the first display screen and the specified display screen

The first initial RGB and the second RGB can be the same color value, such as initial RGB1, initial RGB2 or initial RGB3, but the first initial RGB corresponds to the initial luminance and chrominance parameters, and the second initial RGB corresponds to the specified chromaticity and luminance Parameters, that is, the actual characteristics of different display screens are different, and the color and brightness perceived by the human eye are also different (or the color gamut is different). In order to convert the first display screen to the color gamut of the specified display screen, that is, to make the first display screen display in the specified brightness and chromaticity parameters, the output RGB of the first display screen needs to be converted into the target RGB, and then according to the first initial The one-to-one mapping relationship between RGB and target RGB generates the first LUT.

Assuming that in the color gamut correction system 40, the color module 4036 includes a storage module, which stores the first initial RGB of the first display screen and the corresponding initial brightness and chromaticity parameters, and then the second initial RGB and chromaticity parameters of the specified display screen can be obtained. The corresponding specified luminance and chrominance parameters. Or, the program sets the initial RGB (corresponding to the first initial RGB and the second initial RGB) by default, and correspondingly stores the corresponding initial luminance and chrominance parameters in the memory, and specifies the luminance and chrominance parameters. Optionally, the specified luminance and chrominance parameters can also be read from the temporary storage space in real time. Then, a first LUT is generated by the first LUT generation module, and the first LUT is a one-to-one correspondence table of conversion from the first initial RGB to the target RGB when the display screen is converted from the initial color gamut to the designated color gamut of the designated display screen. The specific process is:

1. Assuming that the first initial RGB is (R0, G0, B0), first convert the first initial RGB to the linear domain through gamma conversion, and obtain the first linear RGB, which is expressed as (r, g, b), the specific conversion formula for:

2. Use the conversion matrix of the specified color gamut to convert the linear rgb to the XYZ tristimulus value. For details, please refer to the following formula:

Among them, Xt, Yt and Zt correspond to the initial chrominance and luminance parameters.

3. After the initial chromaticity and luminance parameters corresponding to the first initial RGB are obtained, they can be converted to the linear space domain value of the target RGB according to the aforementioned formula (8) to obtain the second linear RGB. Specifically:

where (r, g, b) _panel is the second linear rgb, which can be obtained according to Glassman's third law:

After the second linear rgb is obtained, the non-linear RGB value can be obtained by inverse gamma transformation.

Since a fixed gamma value does not necessarily enable accurate conversion of RGB values in the linear domain and the nonlinear domain, in this embodiment of the present application, when performing inverse gamma transformation on the second linear rgb, the corresponding second gamma value Calculated from measured values. Specifically, the formula for obtaining the second gamma value is:

gamma2=log(Y _gray1 /Y _gray2 )/log(Gray1/Gray2) (17)

Among them, gray1 and gray2 represent the grayscale values corresponding to any two groups of RGB values, and Y _gray1 and Y _gray2 respectively represent the corresponding brightness values when the grayscale value is gray1, and the corresponding brightness value when the grayscale value is gray2. The grayscale values corresponding to any two groups of RGB can be obtained by measurement. Then the second gamma value is calculated and obtained according to the measured value.

Finally, perform inverse gamma transformation on the second linear rgb according to gamma2 to obtain the intermediate RGB corresponding to the output of the first display screen. The formula is:

Matrix in the above process

The values in are selected according to the specified luminance and chromaticity parameters, so the intermediate RGB calculated according to this matrix is the theoretically corresponding output RGB (non-linear RGB) when the first display screen is converted to the specified luminance and chromaticity parameters. ). However, due to the limitation of the above-mentioned matrix selection, the intermediate RGB obtained according to the matrix is not necessarily the output RGB corresponding to the first display screen when the luminance and chrominance parameters are specified for display. Therefore, in the embodiment of the present application, it is necessary to further obtain the target RGB, and the target RGB is the output RGB actually corresponding to the first display screen when the specified luminance and chromaticity parameters are displayed.

In the embodiment of the present application, the intermediate RGB is iteratively transformed according to the preset step size, and the corresponding chromaticity and luminance parameters are calculated for the intermediate RGB obtained by each iteration, until it is determined that the measured chromaticity and luminance parameters and the specified If the chrominance and luminance parameters are the same or similar, it is determined that the intermediate RGB is the target RGB. Referring to FIG. 4E, FIG. 4E is a flowchart of determining target RGB provided by an embodiment of the present application. As shown in FIG. 4E, the process includes the following steps:

601. Transform RGB _i according to the preset step size, and obtain corresponding chromaticity and luminance parameter change values;

602. Obtain RGB i+1 according to the preset step size, and obtain the intermediate chromaticity corresponding to RGB i ₊ ₁ according to the intermediate chromaticity and luminance parameters corresponding to the RGB _i and the change values of the chromaticity and luminance parameters and the brightness parameter;

603. Determine whether the difference between the intermediate chromaticity and luminance parameters corresponding to the RGB _i+1 and the specified chromaticity and luminance parameters is less than a preset threshold;

604. If the luminance difference between the intermediate chromaticity and luminance parameters corresponding to the RGB _i+1 and the specified chromaticity and luminance parameters is not less than a preset threshold, set i=i+1, and repeat S1- S3, until the difference between the intermediate chromaticity and luminance parameters corresponding to the RGB _i+1 and the specified chromaticity and luminance parameters is less than a preset threshold, obtain the RGB _i+1 as the target RGB. When i=1, the RGB _i is the intermediate RGB.

The preset step size can be a fixed value composed of ΔR, ΔG and/or ΔB, for example, the preset step size can be (0, 0, ΔR), (0, ΔG, 0) or (ΔR, ΔG, ΔB), etc. . The intermediate RGB obtained by the above matrix calculation is used as the initial value of the iterative transformation, for example, set as RGB ₁ . When the output RGB of the first display screen is RGB ₁ , the corresponding intermediate chromaticity and luminance parameter 1 can be obtained by measurement. If this value is equal to the specified luminance and chromaticity parameters (or the difference between the two is less than the preset threshold), it means The intermediate RGB obtained by the matrix calculation is the target RGB displayed by the first display screen in the specified color gamut, and it is not necessary to perform iterative transformation on the intermediate RGB.

If the difference between the intermediate chromaticity and luminance parameter 1 and the specified chromaticity and luminance parameter is greater than the preset threshold, it means that the current display color gamut of the first display screen is far away from the specified color gamut, and the RGB ₁ is transformed according to the preset step size. , for example, increase or subtract ΔR, ΔG, ΔB from the R, G, B values corresponding to RGB ₁ to obtain RGB2, and the output RGB of the first display screen changes, which also causes changes in the corresponding chromaticity and luminance parameters, and records the chromaticity The change value of the luminance parameter is added and subtracted with the intermediate chromaticity and luminance parameter 1 to obtain the intermediate chromaticity and luminance parameter 2 corresponding to RGB ₂ . The corresponding formula can be expressed as:

Wherein xyY _i+1 is the intermediate chromaticity and luminance parameter corresponding to RGB _i+1 , xyY _i is the intermediate chromaticity and luminance parameter corresponding to RGB _i , and the intermediate chromaticity and luminance parameter 2 corresponds to the case of i=1 in the above formula. RGB includes R parameter, G parameter and B parameter, ΔR, ΔG, ΔB are the preset step size of R parameter, G parameter and B parameter respectively, Δx _R , Δy _R are the color caused by the iteration of R parameter according to the preset step size. The change value of the luminance parameter, ΔY _R is the change value of the luminance parameter caused by the iteration of the R parameter according to the preset step size, Δx _G , Δy _G are the change value of the chrominance parameter caused by the iteration of the G parameter according to the preset step size, ΔY _G is the G Δx _B , Δy _B is the change value of the chrominance parameter caused by the iteration of the B parameter according to the preset step size, ΔY _B is the luminance parameter caused by the iteration of the B parameter according to the preset step size Parameter change value.

Alternatively, it is also possible to directly measure and obtain the intermediate chromaticity and brightness parameter 2 corresponding to the first display screen outputting RGB ₂ . After obtaining the intermediate chrominance and luminance parameters 2, similarly, compare them with the specified chrominance and luminance parameters. If the difference between the two is less than the preset threshold, stop the iteration and use RGB ₂ as the target RGB, otherwise continue to iterate . Until the iteratively obtained RGB _i makes the luminance and chromaticity parameters corresponding to the first display screen the specified luminance and chromaticity parameters, indicating that the color gamut of the first display screen has been converted to the specified color gamut, and the corresponding RGB is the target RGB.

On the first display screen, after the output RGB is converted from the first initial RGB to the target RGB, the displayed luminance and chromaticity parameters are converted from the initial chromaticity and luminance parameters to the specified chromaticity and luminance parameters, that is, the first display screen is converted to Specify the color gamut for display.

It can be seen that, in the embodiment of the present application, the intermediate RGB to which the initial color gamut of the first display screen needs to be converted is calculated by the matrix corresponding to the specified color gamut, and then the intermediate RGB is used as the output RGB of the first display screen, and the corresponding chromaticity is carried out. With the measurement of the brightness parameter, it is determined whether the first display screen is converted to the specified color gamut. If not, iteratively transforms the output RGB according to the preset step size until it is determined that the first display screen is converted to the specified color gamut, and the corresponding target is obtained. RGB. In this process, the gamma value is first determined according to the measured gray value of each display screen, which improves the accuracy of matrix conversion. In addition, the intermediate RGB obtained according to the matrix calculation is not directly used as the first display screen in the specified color gamut. The target RGB is displayed, but iteratively determines the target RGB, which further improves the accuracy of the generated first LUT.

Optionally, the above-mentioned process of obtaining the first LUT can also be performed in other devices or processors. In the color gamut correction system 40, the color module 4036 does not include the first LUT generation module, and the communication module in the system does not include the first LUT generation module. When the third LUT needs to be generated, the first LUT can be directly requested from other devices or processors, which can reduce the system data processing consumption; or the communication module has obtained the first LUT in advance and stored it in the storage module. When there are three LUTs, the first LUT is read from the storage module. Because the first initial RGB can be a value set by default in the program, the target RGB obtained or stored by the system can also be the target RGB corresponding to the first initial RGB, which reduces the storage pressure. The system can also determine the first LUT according to the first initial RGB set by default and the acquired target RGB.

After the first LUT is obtained, the first LUT and the second LUT need to be fused to generate the third LUT. The second LUT is a one-to-one correspondence table of conversion from the second initial RGB to the display RGB when the specified display screen is converted from the specified color gamut to the corresponding color gamut under different application scenarios. If the designated display screen used by the multiple first display screens is the same, then the second LUTs used by them are also the same.

It is known from the foregoing description that the current color gamut (specified color gamut) of the designated display screen can be indicated by the second initial RGB, for example, the input second initial RGB is (0, 0, 16), (0, 32, 16), ..., (255, 255, 255), the corresponding chrominance and luminance parameters are: specify chrominance and luminance parameter 1, specify chrominance and luminance parameter 2, ..., specify chrominance and luminance parameter N, convert to different application modes After displaying the color gamut, the corresponding relationship is shown in Table 5:

Table 5 specifies the color gamut relationship between the display and different application modes

That is, on the specified display screen, the conversion from the specified color gamut to the first display color gamut corresponding to the first application mode is reflected in the conversion of the specified luminance and chromaticity parameters to the display chromaticity and luminance parameters, correspondingly, the output RGB of the specified display screen Convert from second initial RGB to display RGB. The second LUT may only include the correspondence between the second initial RGB and the display RGB, and each application mode corresponds to a second LUT.

The second LUT is generated in other devices or processors, and then the communication interface of the color gamut correction system 40 acquires the second LUT from the server when the third LUT needs to be generated; or the color gamut correction system 40 has acquired and stored the second LUT in advance. For the second LUT, when the third LUT needs to be generated, the second LUT can be read from the memory.

The first LUT and the second LUT are fused to generate a third LUT, including: acquiring the first initial RGB in the first LUT and its corresponding target RGB; determining the real-time first display RGB obtained by the target RGB mapping according to the second LUT; The first initial RGB and the first third LUT showing the mapping relationship of RGB.

Specifically, please refer to FIG. 4F . FIG. 4F is a schematic diagram of a fusion process of a first LUT and a second LUT provided by an embodiment of the present application. As shown in FIG. 4F , after obtaining the target RGB corresponding to the first initial RGB according to the first LUT , take the target RGB as the input value of the second LUT, and find the corresponding display RGB. Because the target RGB corresponds to the specified chromaticity and luminance parameters, and the second initial RGB also corresponds to the specified chromaticity and luminance parameters, then in the case of target RGB=second initial RGB, it can be considered that the correspondence between the second initial RGB and the display RGB is It is the correspondence between target RGB and display RGB. For example, in Figure 4F, when the first initial RGB1 in the first LUT is (0, 0, 16), the corresponding target RGB1 is (0, 0, 32), and the second initial RGB2 in the second LUT is (0, 0, 32). 0,32), the corresponding display RGB2 is (0,0,48), then in the generated third LUT, the display RGB1 corresponding to the first initial RGB1 (0,0,16) is (0,0,48) . If the target RGB in the first LUT does not correspond to the ready-made second initial RGB in the second LUT, an interpolation method or the like may be used to obtain the correspondence between the first initial RGB and the display RGB. For example, in Figure 4F, the target RGB2 corresponding to the first initial RGB2 (0, 0, 32) is (0, 0, 40), and the target RGB2 is the intermediate value of the second initial RGB2 and the second initial RGB3 in the second LUT , can be obtained in LUT2 according to the interpolation of display RGB2 and display RGB3, if the second initial RGB2 is (0, 0, 40), the corresponding color value B of display RGB2 is: (48+72)/2=60, that is The display RGB2 corresponding to the first initial RGB2 (0, 0, 32) is (0, 0, 60).

After the third LUT is generated according to the first LUT and the corresponding second LUT in the first application mode, the first RGB is input to the third LUT for the initial image originally displayed on the first display screen (described by the first RGB) , match or interpolate it with the first initial RGB in the third LUT to obtain the second RGB corresponding to the output, which is used as the display RGB corresponding to the first RGB. The first display displays the chrominance and luminance parameters corresponding to the second RGB, that is, the initial image is converted to the first application mode for display.

It can be seen that, in the embodiment of the present application, a third LUT corresponding to each application mode is generated, and then it is determined according to the third LUT that when the first display screen is converted from the current color gamut to the target color gamut corresponding to each application mode for display, the The correspondence between the first RGB conversion of a pixel to the second RGB. The efficiency of the first display screen from the initial color gamut to the target color gamut of different application modes is improved. In addition, obtaining the first LUT of each display screen converted from the first initial RGB to the target RGB corresponding to the specified chromaticity and brightness parameters is to describe the color corresponding to each display screen in consideration of the actual characteristics of each display screen panel In addition, the second initial RGB corresponding to the specified chromaticity and luminance parameters is obtained and converted to the second LUT of the display RGB in each application mode, and the second LUT is fused according to the first LUT to generate the first LUT. Three LUTs, you can only measure and obtain the corresponding relationship between the specified chromaticity and brightness parameters and the RGB displayed in different application modes, and then combine the first LUT of each display screen to obtain the time when each display screen is converted to different application modes The corresponding relationship of RGB, instead of measuring the corresponding relationship of RGB when each display screen is converted to different application modes, can generate the look-up table required in different scenarios under the condition of a set of test parameters, reduce the measurement time and improve the color space Conversion efficiency, while ensuring conversion accuracy.

In some possible cases, the second LUT can be updated. For example, if a new application mode is added to the mobile phone, including sleep mode, eye protection mode for teenagers, etc., the possibility of specifying the display screen to switch to a different application mode increases, that is, the number of second LUTs increases. Or, if the previous application mode is updated, for example, the contrast and brightness of the video mode are optimized, then the second LUT corresponding to the video mode is updated. In this case, the color gamut correction system 40 can obtain the updated second LUT from other devices through the communication interface. After receiving the updated second LUT sent by the other device, the color gamut correction system 40 stores it in the ROM, and the color module The fusion module in 4036 reads the ROM as needed, obtains the updated second LUT, and then fuses the generated first LUT to generate the third LUT. This method can update the third LUT in real time and improve the display efficiency of the display screen in different application modes.

FIG. 5 is a display processing apparatus provided by an embodiment of the present application, so as to execute the display method in the foregoing embodiment. As shown in FIG. 5 , the device 70 for controlling screen brightness provided in this embodiment may include:

an obtaining module 701, configured to obtain the first RGB of the first pixel to be displayed;

The processing module 702 is used to obtain the third display lookup table LUT corresponding to the first application mode, and the third LUT corresponding to the first application mode is generated according to the fusion of the first LUT and the second LUT corresponding to the first application mode, The third LUT includes a one-to-one correspondence between a plurality of first initial RGB and first display RGB, the first initial RGB corresponds to initial chromaticity and luminance parameters, and the first display RGB corresponds to the first application mode The chromaticity and luminance parameters of the The one-to-one mapping relationship between the initial RGB and the display RGB, the second initial RGB corresponds to the specified luminance and chrominance parameters, the display RGB is related to the application mode, and the same initial RGB corresponds to different application modes. The display RGB is different, and one application mode corresponds to one of the second LUTs;

The processing module 702 is further configured to determine the second RGB corresponding to the first RGB in the first application mode according to the third LUT, and send the second RGB to the first display for display.

Optionally, the obtaining module 701 is further configured to: obtain a third LUT corresponding to the second application mode, and the third LUT corresponding to the second application mode is based on the first LUT and the corresponding second application mode. The second LUT is fused to generate.

Optionally, the obtaining module 701 is further configured to: obtain the first LUT from the memory; or receive the first LUT from the server; or receive from the server according to the preset first initial RGB or obtain the corresponding LUT from the memory. target RGB, and then determine the first LUT.

Optionally, the obtaining module 701 is further configured to: obtain a second LUT corresponding to the first application mode from a plurality of second LUTs stored in the memory; or receive a second LUT corresponding to the first application mode from the server; The second LUT corresponding to the application mode.

Optionally, the obtaining module 701 is further configured to: receive the updated second LUT from the server.

Optionally, the obtaining module 701 is specifically configured to: receive the updated second LUT from the server at a preset time or when a preset instruction is received.

Optionally, the processing module 702 is specifically configured to: obtain the first initial RGB in the first LUT and the corresponding target RGB; determine the real-time first RGB obtained by mapping the target RGB according to the second LUT. a display RGB; generating the third LUT including the mapping relationship between the first initial RGB and the first display RGB.

Optionally, the processing module 702 is specifically configured to: convert the first initial RGB to obtain intermediate RGB; perform iterative transformation on the intermediate RGB according to a preset step size to obtain the target RGB; The one-to-one mapping relationship between the first initial RGB and the target RGB determines the first LUT.

Optionally, the processing module 702 is specifically configured to:

S1: transform RGBi according to the preset step size, and obtain corresponding chromaticity and luminance parameter change values;

S2: Obtain RGBi+1 according to the preset step size, and obtain the intermediate chrominance and luminance parameters corresponding to the RGBi+1 according to the intermediate chrominance and luminance parameters corresponding to the RGBi and the change values of the chrominance and luminance parameters ;

S3: Determine whether the difference between the intermediate chrominance and brightness parameters corresponding to the RGBi+1 and the specified chrominance and brightness parameters is less than a preset threshold; if the intermediate chrominance and brightness parameters corresponding to the RGBi+1 and the specified chromaticity and luminance parameter luminance difference is not less than the preset threshold, then set i=i+1, and repeat S1-S3 until the intermediate chromaticity and luminance parameters corresponding to the RGBi+1 are the same as the described The difference between the specified chrominance and luminance parameters is less than a preset threshold, and when i=1, the RGBi is the intermediate RGB.

Optionally, the processing module 702 is specifically configured to: calculate and obtain the intermediate chromaticity and luminance parameters corresponding to the RGB _i+1 according to the following formula:

The xyY _i+1 is the intermediate chromaticity and luminance parameter corresponding to the RGB _i+1 , the xyY _i is the intermediate chromaticity and luminance parameter corresponding to the RGB _i , the RGB includes the R parameter, the G parameter and B parameter, ΔR, ΔG, ΔB are the R parameter, the preset step size of the G parameter and the B parameter respectively, the Δx _R , Δy _R are the R parameter according to the preset step size The change value of the chrominance parameter caused by the long iteration, ΔY _R is the change value of the luminance parameter caused by the iteration of the R parameter according to the preset step size, Δx _G , Δy _G are the value of the G parameter according to the preset step size The change value of the chrominance parameter caused by the iteration, ΔY _G is the change value of the luminance parameter caused by the iteration of the G parameter according to the preset step size, and the Δx _B , Δy _B are the B parameter according to the preset step size The change value of the chrominance parameter caused by the iteration, ΔY _B is the change value of the luminance parameter caused by the iteration of the B parameter according to the preset step size.

Optionally, the processing module 702 is specifically configured to: perform gamma transformation on the first initial RGB based on the first Gamma value to obtain a first linear rgb; convert the first linear rgb according to a first transformation matrix , to obtain the specified chromaticity and luminance parameters;

Convert the specified luminance and chrominance parameters according to a second transformation matrix to obtain a second linear rgb, and the second transformation matrix is generated according to the measured luminance parameters of the first display;

The intermediate RGB is obtained by performing inverse gamma transformation on the second linear rgb based on a second Gamma value determined according to a measured luminance parameter of the first display.

It should be noted that it should be understood that the division of each module of the apparatus shown in FIG. 5 is only a division of logical functions, and may be fully or partially integrated into a physical entity in actual implementation, or may be physically separated. And these modules can all be implemented in the form of software calling through processing elements; they can also all be implemented in hardware; some modules can also be implemented in the form of software calling through processing elements, and some modules can be implemented in hardware. For example, the processing module 702 may be a separately established processing element, or may be integrated into a certain chip of the apparatus, and may also be stored in the memory of the apparatus in the form of a program, and a certain processing element of the apparatus may The functions of the processing module 702 are called and executed. The implementation of other modules is similar. In addition, all or part of these modules can be integrated together, and can also be implemented independently. The processing element described here may be an integrated circuit with signal processing capability. In the implementation process, each step of the above-mentioned method or each of the above-mentioned units may be completed by an integrated logic circuit of hardware in the processor element or an instruction in the form of software.

The above modules may be one or more integrated circuits configured to implement the above methods, such as: one or more application-specific integrated circuits (ASICs), or, one or more digital signal processors (digital signal processors) signal processor, DSP), or, one or more field-programmable gate arrays (FPGA), etc. For another example, when one of the above modules is implemented in the form of a processing element scheduler, the processing element may be a general-purpose processor, such as a central processing unit (central processing unit, CPU) or other processors that can call programs. For another example, these modules can be integrated together and implemented in the form of a system-on-a-chip (SOC).

FIG. 6 is a schematic diagram of a hardware structure of an apparatus for display processing provided by an embodiment of the present application. As shown in FIG. 6 , the display processing apparatus 80 includes: a processor 801 , a transceiver 802 , a controller 803 and a screen 804 .

Wherein, the transceiver 801 is used to obtain the first RGB of the first pixel to be displayed;

The processor 802 is configured to obtain a third display lookup table LUT corresponding to the first application mode, and the third LUT corresponding to the first application mode is fused according to the first LUT and the second LUT corresponding to the first application mode. Generated, the third LUT includes a one-to-one correspondence between multiple first initial RGBs and first display RGBs, the first initial RGBs correspond to initial chromaticity and luminance parameters, and the first display RGBs correspond to the first The chromaticity and luminance parameters of the application mode; the first LUT includes a one-to-one mapping relationship between a plurality of first initial RGB and target RGB, and the target RGB corresponds to a specified chromaticity and luminance parameter; the second LUT includes a plurality of The one-to-one mapping relationship between the second initial RGB and the display RGB, the second initial RGB corresponds to the specified luminance and chrominance parameters, the display RGB is related to the application mode, and the same second initial RGB is used in different applications The corresponding display RGB in the mode is different, and one application mode corresponds to one of the second LUTs;

The controller 803 is configured to determine the second RGB corresponding to the first RGB in the first application mode according to the third LUT, and send the second RGB to the screen 804 for display.

In this way, the display processing apparatus in this embodiment can execute the display method in the foregoing embodiment, and the specific process and steps of obtaining the third LUT have been described in detail in the foregoing embodiment, and will not be repeated here.

In this way, after the processor 802 determines the first LUT, the transceiver 801 can be used to obtain the first RGB corresponding to the target image to be displayed when displayed in the initial color gamut of the first display screen, and obtain the first RGB according to the first LUT. After one RGB is in the second RGB corresponding to the first application mode, the controller 803 outputs the second RGB to the screen 804 and controls the screen 804 to display in the second RGB, that is, the color corresponding to the target image in the first application mode is completed. The process of displaying the domain will not be repeated here.

In addition, optionally, the apparatus 80 for display processing may further include a memory 805, and the memory 804 is used for storing the first LUT, the second LUT and/or the third LUT obtained from other servers.

Wherein, the screen 804 is usually composed of an organic light emitting display (Organic Light Emitting Display, OLED for short) or an active matrix organic light emitting diode (Active-matrix organic light emitting diode, AMOLED). Exemplarily, the screen 804 is used as an OLED screen for illustration. In order to enable each pixel of the OLED screen to display desired brightness and color, the controller 803 in the display processing device generates corresponding grayscale values according to the second RGB. When the screen is driven with different voltages, it can display different brightness, so as to display the display brightness value corresponding to the input grayscale value.

Specifically, the controller 803 may include a voltage generator 8031 and a brightness controller 8032 . The voltage generator can be used to generate a corresponding reference voltage according to the input gray-scale value; and the brightness controller can be used to control the screen to display a display brightness value corresponding to the input gray-scale value based on the reference voltage.

Wherein, since the input grayscale value is usually a digital signal, in order to convert the input grayscale value into an analog voltage value, optionally, the voltage generator 8031 may be a digital to analog converter (digital to analog converter, DAC). The digital-to-analog converter is used to convert the input grayscale value into an analog reference voltage value, so that the brightness controller 8032 can control the display brightness value of the screen according to the reference voltage, so that the screen displays the corresponding display brightness value when powered on. Specifically, after receiving the input gray-scale value in the form of a digital signal, the digital-to-analog converter can convert the input gray-scale value into an actual reference voltage value. When the input grayscale value is different, the corresponding reference voltage value will also change accordingly, so that the screen can emit light with different brightness under the excitation of different reference voltage value and current value, and display the actual image.

Among them, the processor 802, the transceiver 801, the controller 803 and the memory 805 can use a communication bus or other data paths to realize the transmission of data and signals. Due to the electrical connection between the memory 805 and the processor 802 and the controller 803, the first LUT and/or the second LUT stored in the memory 805 can be transmitted to the processor 802 to generate a third LUT, and then transmit and receive After the controller 801 determines the second RGB according to the obtained first RGB and the third LUT, it is transmitted to the controller 803 to determine the input grayscale value that the pixel should have according to the second RGB, and let the controller 803 determine the input grayscale value according to the input grayscale value. Control the display brightness value of each pixel of the screen 804, etc.

Wherein, the processor 802 is usually the control center of the display processing device, and can be directly connected with different hardware parts such as the memory 805 by means of a communication bus, and by running or executing software programs and/or modules, and calling data stored in the memory , perform various functions of the terminal device and process data, so as to complete the brightness control operation of the screen. The processor 71 may be a microcontroller unit (Microcontroller Unit, MCU), or a central processing unit (central processing unit, CPU), or an independent system-on-a-chip (system-on-a-chip, SOC), or a One or more integrated circuits configured to implement the above method, for example: one or more application specific integrated circuits (ASIC), or, one or more microprocessors (digital singnal processor, DSP), or, One or more field programmable gate arrays (field programmable gate array, FPGA), etc.

Optionally, the processor 802 may include one or more processing units; and use different processing units to execute the above-mentioned different instructions and programs respectively, so as to perform different functions respectively.

While the memory 805 may be read-only memory (ROM) or other types of static storage devices that can store static information and instructions, random access memory (RAM) or other types of static storage devices that can store information and instructions Types of dynamic storage devices, which can also be electrically erasable programmable read-only memory (EEPROM), compact disc read-only memory (CD-ROM), or other optical disk storage, optical disks storage (including compact discs, laser discs, compact discs, digital versatile discs, Blu-ray discs, etc.), magnetic disk storage media or other magnetic storage devices, or capable of carrying or storing desired program code in the form of instructions or data structures and capable of being accessed by Any other medium accessed by the computer, but not limited to this. The memory 805 may exist independently and be connected to the processor 802 and the transceiver 801 through a bus. Memory 805 may also be integrated with processor 802.

In addition to storing the preset gamma correction look-up table, optionally, the memory 805 can also be used to store the application code for executing the solution of the present application, and the execution is controlled by the processor 802 . The processor 802 is configured to execute the application program code stored in the memory 805, so as to implement the screen brightness control method provided by the above embodiments of the present application.

In addition, the display processing device also includes a pulse width modulation (Pulse Width Modulation, PWM) dimmer 806, and the PWM dimmer 806 can modulate the on-off of internal transistor gates or MOS transistor bases and other switching devices , thereby generating a series of pulses with the same pulse width, and by changing the pulse width or duty cycle to achieve different equivalent analog outputs, thereby adjusting the output brightness of the screen 804 . Exemplarily, the PWM dimmer 806 is electrically connected to the screen 804. The PWM dimmer 806 can receive digital signals from the control chip and convert the digital signals into pulses with different pulse widths or duty cycles. The equivalent output voltage signals with different amplitudes, with the different magnitudes of the voltage signals, each pixel on the screen 804 will also display different brightness, thereby realizing the normal display and brightness adjustment of the image. Exemplarily, the PWM dimmer 806 may be electrically connected to the processor 802 or be a part of the controller 803 to adjust the display brightness of the screen 804 according to input data such as grayscale values.

In the above-mentioned embodiments, it may be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented using a software program, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on the computer, all or part of the processes or functions described in the embodiments of the present application are generated. The computer may be a general purpose computer, special purpose computer, computer network, or other programmable device. The computer instructions may be stored in or transmitted from one computer-readable storage medium to another computer-readable storage medium, for example, the computer instructions may be downloaded from a website site, computer, server, or data center Transmission to another website site, computer, server, or data center by wire (eg, coaxial cable, optical fiber, digital subscriber line, DSL) or wireless (eg, infrared, wireless, microwave, etc.). The computer-readable storage medium can be any available medium that can be accessed by a computer or data storage devices including one or more servers, data centers, etc. that can be integrated with the medium. The usable media may be magnetic media (eg, floppy disks, hard disks, magnetic tapes), optical media (eg, DVDs), or semiconductor media (eg, solid state disks (SSDs)), and the like.

Claims

A method for display processing, characterized in that the method comprises:

obtaining the first RGB of the first pixel to be displayed;

Obtain the third display lookup table LUT corresponding to the first application mode, the third LUT corresponding to the first application mode is generated according to the fusion of the first LUT and the second LUT corresponding to the first application mode, and the third LUT includes One-to-one correspondence between a plurality of first initial RGBs and first display RGBs, the first initial RGBs correspond to initial chrominance and luminance parameters, and the first display RGBs correspond to chrominance and luminance parameters of the first application mode The first LUT includes a one-to-one mapping relationship between a plurality of first initial RGB and target RGB, and the target RGB corresponds to specified chromaticity and luminance parameters; The second LUT includes a plurality of second initial RGB and display RGB One-to-one mapping relationship, the second initial RGB corresponds to the specified luminance and chrominance parameters, the display RGB is related to the application mode, and the same second initial RGB corresponds to different display RGB in different application modes, One application mode corresponds to one of the second LUTs;

The second RGB corresponding to the first RGB in the first application mode is determined according to the third LUT, and the second RGB is sent to the first display for display.
The method according to claim 1, wherein the method further comprises:

A third LUT corresponding to the second application mode is acquired, where the third LUT corresponding to the second application mode is generated by fusion of the first LUT and the second LUT corresponding to the second application mode.
The method according to claim 1 or 2, wherein the method further comprises:

obtain the first LUT from memory; or

receive the first LUT from a server; or

According to the preset first initial RGB, the corresponding target RGB is received from the server or obtained from the memory, and then the first LUT is determined.
The method according to any one of claims 1-3, wherein the method further comprises:

Acquire a second LUT corresponding to the first application mode from a plurality of second LUTs stored in the memory; or receive a second LUT corresponding to the first application mode from the server.
The method according to any one of claims 1-4, wherein the method further comprises: receiving an updated second LUT from the server.
The method according to claim 5, wherein the receiving the updated second LUT from the server comprises: receiving the updated second LUT from the server at a preset time or when a preset instruction is received Second LUT.
The method according to any one of claims 1-6, wherein the obtaining the third LUT comprises:

Obtain the first initial RGB in the first LUT and the corresponding target RGB;

Determine the real-time first display RGB obtained by the target RGB according to the second LUT mapping;

The third LUT including the mapping relationship between the first initial RGB and the first display RGB is generated.
The method according to any one of claims 1-7, wherein the acquiring the first LUT comprises:

Converting the first initial RGB to obtain intermediate RGB;

Perform iterative transformation on the intermediate RGB according to a preset step size to obtain the target RGB;

The first LUT is determined according to a one-to-one mapping relationship between the first initial RGB and the target RGB.
The method according to claim 8, wherein the iteratively transforming the intermediate RGB according to a preset step size to obtain the target RGB comprises:

S1: transform RGB i according to the preset step size, and obtain the corresponding chromaticity and luminance parameter change values;

S2: Obtain RGB i+1 according to the preset step size, and obtain the intermediate chromaticity corresponding to the RGB i + 1 according to the intermediate chromaticity and luminance parameters corresponding to the RGB i and the change values of the chrominance and luminance parameters and the brightness parameter;

S3: Determine whether the difference between the intermediate chromaticity and luminance parameters corresponding to the RGB i +1 and the specified chromaticity and luminance parameters is less than a preset threshold; If the luminance difference between the luminance parameter and the specified chromaticity and luminance parameters is not less than the preset threshold, then set i=i+1, and repeat S1-S3 until the intermediate chromaticity and luminance parameters corresponding to the RGB i+1 The difference from the specified chrominance and luminance parameters is less than a preset threshold, and when i=1, the RGB i is the intermediate RGB.
The method according to claim 9, wherein the intermediate chromaticity and luminance corresponding to the RGB i+1 are obtained according to the intermediate chromaticity and luminance parameters corresponding to the RGB i and the change values of the chrominance and luminance parameters parameters, including obtaining the intermediate chromaticity and brightness parameters corresponding to the RGB i+1 according to the following formula:

The xyY i+1 is the intermediate chromaticity and luminance parameter corresponding to the RGB i+1 , the xyY i is the intermediate chromaticity and luminance parameter corresponding to the RGB i , the RGB includes the R parameter, the G parameter and B parameter, ΔR, ΔG, ΔB are the R parameter respectively, the preset step size of the G parameter and the B parameter, Δx R Δy R is the R parameter according to the preset step The change value of the chrominance parameter caused by the long iteration, ΔY R is the change value of the luminance parameter caused by the iteration of the R parameter according to the preset step size, and the Δx G , Δy G are the G parameter according to the preset The change value of the chrominance parameter caused by the step size iteration, ΔY G is the change value of the luminance parameter caused by the G parameter iteration according to the preset step size, and the Δx B , Δy B are the B parameter according to the preset value. The change value of the chrominance parameter caused by the step size iteration, ΔY B is the change value of the luminance parameter caused by the B parameter iteration according to the preset step size.
The method according to any one of claims 8-10, wherein the converting the initial RGB to obtain the intermediate RGB comprises:

Perform gamma transformation on the first initial RGB based on the first Gamma value to obtain a first linear rgb;

Convert the first linear rgb according to the first transformation matrix to obtain the specified chrominance and luminance parameters;

Convert the specified luminance and chrominance parameters according to a second transformation matrix to obtain a second linear rgb, and the second transformation matrix is generated according to the measured luminance parameters of the first display;

The intermediate RGB is obtained by performing inverse gamma transformation on the second linear rgb based on a second Gamma value determined according to a measured luminance parameter of the first display.
A device for display processing, characterized in that the device comprises:

an acquisition module for acquiring the first RGB of the first pixel to be displayed;

The processing module is used to obtain the third display lookup table LUT corresponding to the first application mode, and the third LUT corresponding to the first application mode is generated according to the fusion of the first LUT and the second LUT corresponding to the first application mode. The third LUT includes a one-to-one correspondence between a plurality of first initial RGB and the first display RGB, the first initial RGB corresponds to the initial chromaticity and luminance parameters, and the first display RGB corresponds to the first application mode. Chroma and luminance parameters; the first LUT includes a one-to-one mapping relationship between a first plurality of initial RGB and target RGB, and the target RGB corresponds to a specified chromaticity and luminance parameter; the second LUT includes a second initial RGB One-to-one mapping relationship between RGB and display RGB, the second initial RGB corresponds to the specified luminance and chrominance parameters, the display RGB is related to the application mode, and the same second initial RGB corresponds to different application modes The display RGB is different, and one application mode corresponds to one of the second LUTs;

The processing module is further configured to determine the second RGB corresponding to the first RGB in the first application mode according to the third LUT, and send the second RGB to the first display for display.
The apparatus according to claim 12, wherein the processing module is further configured to: obtain a third LUT corresponding to the second application mode, wherein the third LUT corresponding to the second application mode is based on the first LUT and the The second LUT corresponding to the second application mode is generated by fusion.
The device according to claim 12 or 13, wherein the acquiring module is further configured to:

obtain the first LUT from memory; or

receive the first LUT from a server; or

According to the preset first initial RGB, the corresponding target RGB is received from the server or obtained from the memory, and then the first LUT is determined.
The device according to any one of claims 12-14, wherein the acquiring module is further configured to:

Acquire a second LUT corresponding to the first application mode from a plurality of second LUTs stored in the memory; or receive a second LUT corresponding to the first application mode from the server.
The apparatus according to any one of claims 12-15, wherein the obtaining module is further configured to: receive an updated second LUT from the server.
The apparatus according to claim 16, wherein the obtaining module is specifically configured to: receive the updated second LUT from the server at a preset time or when a preset instruction is received.
The device according to any one of claims 12-17, wherein the processing module is specifically configured to:

Obtain the first initial RGB in the first LUT and the corresponding target RGB;

Determine the real-time first display RGB obtained by the target RGB according to the second LUT mapping;

The third LUT including the mapping relationship between the first initial RGB and the first display RGB is generated.
The device according to any one of claims 12-18, wherein the processing module is specifically configured to:

Converting the first initial RGB to obtain intermediate RGB;

Perform iterative transformation on the intermediate RGB according to a preset step size to obtain the target RGB;

The first LUT is determined according to a one-to-one mapping relationship between the first initial RGB and the target RGB.
The device according to claim 19, wherein the processing module is specifically configured to:

S1: transform RGBi according to the preset step size, and obtain corresponding chromaticity and luminance parameter change values;

S2: Obtain RGBi+1 according to the preset step size, and obtain the intermediate chrominance and luminance parameters corresponding to the RGBi+1 according to the intermediate chrominance and luminance parameters corresponding to the RGBi and the change values of the chrominance and luminance parameters ;

S3: Determine whether the difference between the intermediate chromaticity and brightness parameters corresponding to the RGBi+1 and the specified chromaticity and brightness parameters is less than a preset threshold; if the intermediate chromaticity and brightness parameters corresponding to the RGBi+1 and the specified chromaticity and luminance parameter luminance difference is not less than the preset threshold, then set i=i+1, and repeat S1-S3 until the intermediate chromaticity and luminance parameters corresponding to the RGBi+1 are the same as the described The difference between the specified chrominance and luminance parameters is less than a preset threshold, and when i=1, the RGBi is the intermediate RGB.
The device according to claim 20, wherein the processing module is specifically configured to: calculate and obtain the intermediate chromaticity and luminance parameters corresponding to the RGB i+1 according to the following formula:

The xyY i+1 is the intermediate chromaticity and luminance parameter corresponding to the RGB i+1 , the xyY i is the intermediate chromaticity and luminance parameter corresponding to the RGB i , the RGB includes the R parameter, the G parameter and B parameter, the ΔR, ΔG, ΔB are the R parameter, the preset step size of the G parameter and the B parameter, the Δx R , Δy R are the R parameter according to The chrominance parameter change value caused by the preset step size iteration, ΔY R is the luminance parameter change value caused by the R parameter iteration according to the preset step size, and the Δx G , Δy G are the G parameters The change value of the chrominance parameter caused by the iteration according to the preset step size, ΔY G is the change value of the luminance parameter caused by the iteration of the G parameter according to the preset step size, and the Δx B , Δy B are the B parameters The change value of the chrominance parameter caused by the iteration according to the preset step size, ΔY B is the change value of the luminance parameter caused by the iteration of the B parameter according to the preset step size.
The device according to any one of claims 19-21, wherein the processing module is specifically configured to:

Perform gamma transformation on the first initial RGB based on the first Gamma value to obtain a first linear rgb;

Convert the first linear rgb according to the first transformation matrix to obtain the specified chrominance and luminance parameters;

Convert the specified luminance and chrominance parameters according to a second transformation matrix to obtain a second linear rgb, and the second transformation matrix is generated according to the measured luminance parameters of the first display;

The intermediate RGB is obtained by performing inverse gamma transformation on the second linear rgb based on a second Gamma value determined according to a measured luminance parameter of the first display.
A display processing device, characterized in that the display image processing device includes a processor and an interface circuit, the interface circuit is coupled to the processor, and the processor is configured to execute code instructions stored in a memory to A method as claimed in any one of claims 1 to 11 is performed.
A computer-readable storage medium, characterized in that, program instructions are stored in the computer-readable storage medium, and when the program instructions are executed on a computer or a processor, the computer or the processor is made to execute the The method of any one of claims 1-11.