CN115578984A

CN115578984A - Display control method and device and display equipment

Info

Publication number: CN115578984A
Application number: CN202211017614.1A
Authority: CN
Inventors: 段立业
Original assignee: BOE Technology Group Co Ltd; Beijing BOE Technology Development Co Ltd
Current assignee: BOE Technology Group Co Ltd; Beijing BOE Technology Development Co Ltd
Priority date: 2022-08-23
Filing date: 2022-08-23
Publication date: 2023-01-06

Abstract

The invention discloses a display control method, a display control device and display equipment, wherein the control method comprises the following steps: acquiring display brightness of a display module and an original image signal output to a display driving circuit of the display module; converting the original image signal into an intermediate image signal according to the display brightness; a first bit depth of the original image signal is greater than or equal to a second bit depth of the intermediate image signal, and the display brightness is positively correlated with the second bit depth; sending the intermediate image signal to the display driving circuit so that the display driving circuit converts the intermediate image signal into a target image signal and outputs and displays the target image signal; the third bit depth of the target image signal is the same as the first bit depth. The method can reduce the transmission power consumption of the image signal and the driving power consumption of the display driving circuit when the display module is at low brightness.

Description

Display control method and device and display equipment

Technical Field

The present application relates to the field of display technologies, and in particular, to a display control method and apparatus, and a display device.

Background

When a display or an electronic device equipped with the display is used, the brightness of the display is usually required to be adjusted, taking a current smart phone as an example, the smart phone has a function of automatically adjusting the brightness according to the environment, and also has a function of manually adjusting the brightness according to the user instruction, please refer to fig. 1, and the brightness of the screen is correspondingly changed by sliding the brightness control bar through a gesture.

At present, a Liquid Crystal Display (AMLCD) is often mounted on a Display or an electronic device, such as an Active Matrix Liquid Crystal Display (AMLCD). In the aspect of brightness control, please refer to fig. 2 for the principle, a display driving circuit 2' of the display is connected to a signal source 1' such as a CPU or a GPU through a data line, a backlight driving circuit 3' is connected to the signal source 1' through a single line single-wire, the signal source 1' sends an image signal to the display driving circuit 2' and sends a control command to the backlight driving circuit 3' to adjust the brightness of a backlight module 4' such as a Light Emitting Diode (LED), and the backlight driving circuit 3' can control the brightness change in 2 ways: one is "DC dimming". DC dimming changes the brightness of the screen by increasing or decreasing the current of the LEDs; after the LED is turned on, the brightness of the LED is basically proportional to the current, so that the brightness of the display screen can be changed by changing the current; the other one is PWM dimming, and the on-off alternation of the display screen is controlled instead of changing the power during the PWM dimming; in the process of turning on and off the screen, the longer the duration time of the screen-off state is, the lower the brightness of the screen to the naked eyes is; the longer the lighting time is, the less the screen-off time is, and the brighter the screen is.

The control method of the display brightness has the following problems: when the user turns down the brightness of the display, although the power of the backlight module is reduced, the image transmission power consumption of the display is not changed compared with that of the display at high brightness, so that unnecessary power consumption loss is generated.

Disclosure of Invention

The invention provides a display control method, a display control device and display equipment, which can reduce the image transmission power consumption of a display module at low brightness.

In a first aspect, the present application provides the following technical solutions through an embodiment:

a display control method comprising:

acquiring display brightness of a display module and an original image signal output to a display driving circuit of the display module;

converting the original image signal into an intermediate image signal according to the display brightness; a first bit depth of the original image signal is greater than or equal to a second bit depth of the intermediate image signal, and the display brightness is positively correlated with the second bit depth;

sending the intermediate image signal to the display driving circuit so that the display driving circuit converts the intermediate image signal into a target image signal and outputs and displays the target image signal; the third bit depth of the target image signal is the same as the first bit depth.

Optionally, the converting the original image signal into an intermediate image signal according to the display brightness includes:

determining the second bit depth according to the display brightness and a preset mapping relation between the display brightness and the bit depth;

and converting the original image signal into the intermediate image signal according to the second bit depth.

determining a target brightness interval to which the display brightness belongs from a plurality of preset brightness intervals according to the display brightness; each brightness interval corresponds to one bit depth;

converting the original image signal into an intermediate image signal according to the bit depth of the target brightness interval; the second bit depth is the bit depth of the target brightness interval.

Optionally, the preset multiple luminance intervals are obtained by dividing based on luminance values 0 to 255, and the size of the luminance interval is positively correlated with the luminance average value of the luminance interval.

Optionally, if the first bit depth is N, the number of the luminance intervals is N-1, and the value range of the second bit depth is [2,N ]; n is an integer of 6 or more.

Optionally, the preset multiple luminance intervals include a first luminance interval, a second luminance interval, a third luminance interval, a fourth luminance interval, a fifth luminance interval, a sixth luminance interval, and a seventh luminance interval;

the first brightness interval is [0,3], and the bit depth corresponding to the first brightness interval is 2;

the second brightness interval is [4,7], and the bit depth corresponding to the second brightness interval is 3;

the third brightness interval is [8,15], and the bit depth corresponding to the third brightness interval is 4;

the fourth brightness interval is [16,31], and the bit depth corresponding to the fourth brightness interval is 5;

the fifth brightness interval is [32,63], and the bit depth corresponding to the fifth brightness interval is 6;

the sixth brightness interval is [64,127], and the bit depth corresponding to the sixth brightness interval is 7;

the seventh luminance interval is [128,255], and the bit depth corresponding to the seventh luminance interval is 8.

Optionally, the original image signal includes N bits of first data corresponding to a plurality of sub-pixels; the converting the original image signal into an intermediate image signal according to the display luminance includes:

for each sub-pixel, right-shifting the first data with N bits by M bits to obtain second data with N bits; n is the first bit depth, M is the difference between the first bit depth and the second bit depth;

removing M high-bit values in the N bits of the second data to obtain P bits of third data;

obtaining the intermediate image signal based on the P-bit third data respectively corresponding to the plurality of sub-pixels; p is the second bit depth.

Optionally, the sending the intermediate image signal to the display driving circuit to enable the display driving circuit to convert the intermediate image signal into a target image signal and output the target image signal for display includes:

sending the intermediate image signal to the display driving circuit to cause the display driving circuit to perform:

for the P-bit third data of each sub-pixel, supplementing a preset coding value to the coding end of the third data to obtain N-bit fourth data;

and obtaining the target image signal according to the N bits of fourth data respectively corresponding to the plurality of sub-pixels to output and display.

In a second aspect, based on the same inventive concept, the present application provides the following solutions through an embodiment:

a display control apparatus comprising:

the acquisition module is used for acquiring the display brightness of the display module and an original image signal output to a display driving circuit of the display module;

the conversion module is used for converting the original image signal into an intermediate image signal according to the display brightness; a first bit depth of the original image signal is greater than or equal to a second bit depth of the intermediate image signal, and the display brightness is positively correlated with the second bit depth;

the sending module is used for sending the intermediate image signal to the display driving circuit so as to enable the display driving circuit to convert the intermediate image signal into a target image signal and output and display the target image signal; the third bit depth of the target image signal is the same as the first bit depth.

In a third aspect, based on the same inventive concept, the present application provides, by way of an embodiment, the following solutions:

a display device comprises a processor, a converter and a display module; the converter is connected between the processor and the display module;

the converter is used for: acquiring the display brightness of the display module and an original image signal output by the processor; converting the original image signal into an intermediate image signal according to the display brightness; sending the intermediate image signal to the display module; a first bit depth of the original image signal is greater than or equal to a second bit depth of the intermediate image signal, and the display brightness is positively correlated with the second bit depth;

the display module assembly is used for: converting the intermediate image signal into a target image signal and outputting and displaying the target image signal; the third bit depth of the target image signal is the same as the first bit depth.

Through one or more technical schemes of the invention, the invention has the following beneficial effects or advantages:

the invention provides a display control method, which comprises the steps of converting an original image with a first bit depth output to a display driving circuit of a display module into an intermediate image with a second bit depth according to the display brightness of the display module, wherein the first bit depth is greater than or equal to the second bit depth; the bit depth of the intermediate image is associated with the display brightness of the display module, and when the display brightness is reduced, the bit depth of the output original image is reduced, so that the image data quantity transmitted from the signal source to the display driving circuit can be reduced, and the transmission power consumption of the image is reduced; through with display luminance and second bit depth positive correlation, when the luminance of display module assembly was lower promptly, the corresponding second bit depth was also lower, has still reduced the drive power consumption of display drive circuit when low luminance when reducing image signal transmission power consumption. In addition, the display driving circuit converts the intermediate image with the second bit depth into a target image signal and outputs the target image signal after receiving the intermediate image with the second bit depth, and the third bit depth of the target image signal is the same as the first bit depth of the original image signal, so that the display quality of the display module under low brightness is not influenced.

The foregoing is a summary of the present invention, and the following features are exemplary embodiments of the present invention in order to make the technical aspects of the present invention more clearly understandable.

Drawings

Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the invention. Also, like reference numerals are used to refer to like parts throughout the drawings. In the drawings:

fig. 1 shows a schematic diagram of currently adjusting brightness in an electronic device;

FIG. 2 is a schematic diagram illustrating the brightness control principle of the present display;

FIG. 3 shows a schematic diagram of a display control method according to an embodiment of the invention;

FIG. 4 shows a schematic diagram of a dimming implementation of a display according to an embodiment of the invention;

FIG. 5 is a diagram illustrating a correspondence between a bit depth of an image signal and a display luminance according to an embodiment of the present invention;

FIG. 6 shows a schematic diagram of a display device according to an embodiment of the invention;

fig. 7 shows a schematic diagram of a display control apparatus according to an embodiment of the present invention.

Detailed Description

Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

At present, various displays and electronic devices commonly use LCD liquid crystal displays, liquid crystal is an organic compound between solid and liquid, and the liquid crystal has the liquidity of liquid and the optical anisotropy of crystal under the condition of normal temperature, can be changed into transparent liquid when heated, and can be changed into a crystallized turbid solid after being cooled.

Under the action of the electric field, the liquid crystal molecules are arranged to change, so that the incident light beam penetrates through the liquid crystal to generate intensity change, and the intensity change is further represented as light and shade change through the action of the polarizer. Therefore, the light and shade change of the light can be realized by controlling the liquid crystal electric field, thereby achieving the purpose of information display. Thus, the liquid crystal material acts like a small "light valve" one by one.

The control circuit and the drive circuit are arranged around the liquid crystal material. When an electric field is generated by the electrodes in the LCD, the liquid crystal molecules are twisted, so that the light passing through the liquid crystal molecules is regularly refracted (the optical rotation property of the liquid crystal material), and then filtered by the second polarizer to be displayed on the screen.

Since the liquid crystal material does not emit light, the LCD generally needs to provide an additional light source for the display panel, the main light source system is called as "backlight module", and most of the current backlight modules employ Light Emitting Diodes (LEDs).

Through analysis, it is found that in the current display, especially in the backlight AMLCD display, when the user turns down the brightness of the display, although the current of the LEDs in the backlight module is reduced and the power is reduced, the color depth of the image data received by the display driving chip (IC) in the display is not changed, and the transmission power consumption of all the images is not changed with the display at high brightness. Research shows that the number of screen gray scales perceived by human eyes can be divided into about 256 (8-bit color depth) when the screen brightness is maximum, and the number of gray scales perceived by human eyes can be rapidly reduced when the brightness is reduced, and the number of gray scales perceived by human eyes is even lower than 10 when the screen is at the lowest brightness. However, at this time, the signal source of the display (e.g. CPU in the mobile phone, GPU in the computer) still sends 256-level (8-bit color depth) data to the display, and at this time, a large amount of data cannot be perceived by human eyes, and the large amount of data sent at this time means a larger power consumption for image transmission, so that some power consumption at low brightness of the display can be saved.

For the above reasons, the present invention is proposed to solve the problem that the image transmission power consumption of the display is large at low luminance. In a first aspect, an alternative embodiment provides a display control method, please refer to fig. 3, which includes steps S101 to S103, specifically as follows:

s101: acquiring display brightness of a display module and an original image signal output to a display driving circuit of the display module; specifically, the original image signal is image data sent by a signal source to a display driving circuit of the display module, such as image data sent by a CPU, a GPU, and the like of the electronic device to the display driving circuit of the display module. The display module can be a display screen of a mobile phone, a computer display module, a display screen of a tablet computer, and the like. The display module that can be understood can include a display driving circuit and a display panel, and the display panel can be a commonly used display panel, and the type is not limited, for example, when being an LCD panel, the display panel can be composed of a backlight module, an array substrate, a color film substrate, and the like, and the specific structure can be understood with reference to the prior art, and is not described herein again. The display driving circuit may include, but is not limited to, a gate driver, a source driver, and a TCON (timing controller).

Luminance (luminosity) is a property of a color, or a dimension of the color space that is related to the brightness of the color. In Lab color space, luminance is defined to reflect the subjective perception of brightness of humans.

For a display module, the brightness is the brightness of the display screen, and the unit is candela per square meter (cd/m) ² ) Or nits, which is the candle power per square meter. There are two current methods for improving the brightness of a display screen, one is to improve the light passing rate of an LCD panel; the other is to increase the brightness of the backlight module. Currently, the LCD brightness research has reached 800nits or even higher.

In the field of computer graphics, gray scale (Gray scale) digital images are images that have only one sample color per pixel. Such images are typically displayed in gray scale from darkest black to brightest white, although in theory this sample may represent different shades of any color and may even be different colors at different brightnesses. The gray image is different from the black and white image, the black and white image only has two colors of black and white in the field of computer image, and the gray image has a plurality of levels of color depth between black and white. However, outside the field of digital images, a "black-and-white image" also means a "grayscale image", and for example, a photograph of grayscale is generally called a "black-and-white photograph". In some articles relating to digital images, monochrome images are equivalent to grayscale images, and in other articles to black and white images. In the display field, the color or gray scale refers to the difference between brightness and darkness of the display pixels in the black-and-white display module, and the difference in color is expressed in the color display module, and the more the gray scale is, the clearer and more vivid the image gradation is. The gray scale level depends on the number of bits of the refreshed memory cells corresponding to each pixel and the performance of the display module itself.

S102: converting the original image signal into an intermediate image signal according to the display brightness; the first bit depth of the original image signal is greater than or equal to the second bit depth of the intermediate image signal, and the display brightness is positively correlated with the second bit depth.

In the field of digital images, the color depth and bit depth of an image are different concepts. Color depth refers to "depth of Color", and in digital images, the smallest unit is a pixel (pixel), where a pixel is a Color pixel. If the color of each pixel is represented by a 16-bit binary number, it is called a 16-bit map, which can express 2 to the power of 16, namely 65536 colors; if each pixel is represented by a 24-bit binary number, referred to as a 24-bit map, it can express 2 to the power of 24, i.e., 16777216 colors. Each pixel has independent parameters, and in the case of an RGB three-channel image, each pixel is composed of three channels, R, G, and B, wherein each channel is represented by a plurality of binary bits to indicate its "content". For example, 11001101100110011111111 (24 bit map), representing 102 red, 204 green and 255 blue, is "sky blue" according to additive color theory. Thus, "color depth" is used to indicate the 2-digit number of the color, i.e., 24 bits. In addition, although many digital images are not represented in RGB, but in YUV, their parametric description in color depth is the same.

The concept of bit depth is relatively wide, and can be used to describe the precision of quantizing analog signals or simulating digital signals, and in the display field or image field, the most basic unit displayed by the display module is a point, and is used to describe the number of pulse signal bits of each point brightness, which is called as "bit depth".

Thus in the display field the bit depth can be understood as bits per channel, i.e. channel bit depth, the color depth can be understood as bits per pixel, for RGB images the bit depth is the bit width of each channel, e.g. 8 bits, and the color depth = the sum of the bit depths of the three channels, i.e. 24 bits.

The color depth and bit depth of common digital images are related as follows:

color depth: 18bit (RGB/YUV), bit depth is 6bit;

color depth: 24bit (RGB/YUV), 8bit depth;

color depth: 30bit (RGB/YUV), bit depth is 10bit;

color depth: 32bit (RGBA), 8bit deep;

color depth: 40 bits (RGBA/YUVA) with a bit depth of 10 bits.

In step S102 of this embodiment, the bit depth of the original image signal is adjusted according to the current display brightness of the display module, and when the display brightness is reduced, the bit depth of the original image signal is reduced, so as to synchronously reduce the color depth of the original image, thereby achieving the purpose of reducing the data transmission amount from the signal source to the display driving circuit of the display module.

The display brightness is positively correlated with the second bit depth, which means that the value of the second bit depth is smaller as the display brightness is reduced. The positive correlation may be a linear correlation, an exponential correlation, a polynomial correlation, or the like. In addition, the positive correlation may be that one value of the display luminance corresponds to one second bit depth (one-to-one), or that a plurality of values of the display luminance correspond to one second bit depth (many-to-one), which is not limited herein.

Then, converting the original image signal into the intermediate image signal according to the display brightness means that the original image signal with the first bit depth is converted into the intermediate image signal with the second bit depth according to the difference of the current display brightness, so that the color depth of the image signal is reduced and the data transmission amount is reduced. The first bit depth is the bit depth of the image signal output by the signal source, for the display module, the bit depth of the commonly used image signal is 8 bits and 10 bits, and the pixel point is composed of RGB, so the color depth of the corresponding image is 24bbit and 30 bits.

Schemes that can be adopted to convert the original image signal into the intermediate image signal according to the display luminance may include:

according to the first scheme, the second bit depth is determined according to the display brightness and a preset mapping relation between the display brightness and the bit depth; the original image signal is converted into an intermediate image signal according to the second bit depth.

Specifically, the mapping relationship may be a functional relationship between the display brightness and the bit depth, or may be a corresponding relationship table between the display brightness and the bit depth. If the function relationship is true, the display brightness is taken as the independent variable input function relationship to obtain the corresponding bit depth; if the table is a corresponding relation table, the table can be looked up by using the display brightness to obtain the corresponding bit depth.

According to the second scheme, a target brightness interval to which the display brightness belongs is determined from a plurality of preset brightness intervals; each brightness interval corresponds to one bit depth; converting the original image signal into an intermediate image signal according to the bit depth of the target brightness interval; the second bit depth is the bit depth of the target brightness interval.

Specifically, the brightness range of the display module can be divided into a plurality of brightness intervals in advance through research, and then a corresponding bit depth is determined for each brightness interval. The range and number of the brightness intervals can be determined according to the gray scale number of the color channel or the brightness range of the display module. After the current display brightness of the display module is obtained, the brightness interval to which the current display brightness belongs can be determined, and therefore the second bit depth corresponding to the current display brightness can be determined quickly.

The actual brightness (in nit) of the display module screen is related to two parameters: one is that when a user operates the display module or the electronic device with the display module, the brightness control bar is adjusted through gestures or a controller, and for the LCD, the brightness value of the backlight module is adjusted by the brightness control bar; if the display is an OLED (organic light emitting diode) or the like without a backlight module, the full-screen brightness value is adjusted; the other is the gray scale number or the gray scale value, for a display with 8bit width, the gray scale number divides the transmittance of the screen into 256 levels, and the gray scale value of each pixel is independently controllable.

For example, a certain LCD uses 10000nit of backlight module, the maximum pass rate is 10%, and then 1000nit at 256 gray level and 300nit at 128 gray level can be obtained. If the backlight is adjusted to 1000nit, then 100nit at 256 gray levels and 30nit at 128 gray levels can be obtained.

Since different screens have different display luminance ranges, in the implementation of a program, for the purpose of generalized control, the display luminance ranges of the screens may be unified to a luminance value range of [ N0, N255], and therefore, a plurality of preset luminance sections are obtained by dividing based on the luminance values 0 to 255, and the size of the luminance section is positively correlated with the luminance average value of the luminance section.

The positive correlation between the size of the brightness interval and the brightness mean value of the brightness interval means that the ranges of different brightness intervals are not uniform, but satisfy the rule that the smaller the brightness value is, the smaller the distance between the upper limit and the lower limit of the corresponding brightness interval is, the larger the brightness value is, and the larger the distance between the upper limit and the lower limit of the corresponding brightness interval is. The principle of this arrangement is to consider that the gray-scale values of the sub-pixels RGB and the display luminance of the display module are not simply linear relationships, but are power functions, as shown in fig. 4. The exponent of the power function is called the Gamma value, which is typically 2.2, and this scaling process is called the Gamma correction. Therefore, the size of the brightness interval is positively correlated with the brightness mean value of the brightness interval, so that the adjustment range of the second bit depth can be ensured to be more matched with the change of the actual brightness of the display module, and the display quality of the display module can not be obviously reduced while the power consumption of image signal transmission is reduced.

The number of luminance sections may be related to the bit depth of the original image signal. In some optional embodiments, if the first bit depth is N, the number of the luminance intervals is N-1, and the value range of the second bit depth is [2,N ]; n is not less than 6 and is an integer.

The bit width of the common display module is 8bit or 10bit, that is, the bit width of the original image signal is 8bit or 10bit, which is taken as an example to illustrate:

for 8 bits: seven luminance intervals can be preset, specifically as follows:

For 10 bits: 9 brightness intervals can be preset, specifically as follows:

the first brightness interval is [0,1], and the bit depth corresponding to the first brightness interval is 2;

the second brightness interval is [1,3], and the bit depth corresponding to the second brightness interval is 3;

the third brightness interval is [4,7], and the bit depth corresponding to the third brightness interval is 4;

the fourth brightness interval is [8,15], and the bit depth corresponding to the fourth brightness interval is 5;

the fifth brightness interval is [16,31], and the bit depth corresponding to the fifth brightness interval is 6;

the sixth brightness interval is [32,64], and the bit depth corresponding to the sixth brightness interval is 7;

the seventh luminance interval is [64,127], and the bit depth corresponding to the seventh luminance interval is 8.

The eighth brightness interval is [128,191], and the bit depth corresponding to the eighth brightness interval is 9;

the ninth brightness interval is [192,255], and the bit depth corresponding to the ninth brightness interval is 10.

In some embodiments, the dividing of the luminance interval may also consider the actual luminance value (nit) of the display module, and the following scheme may be adopted:

if the brightness interval is

The corresponding bit depth is 2;

if the display interval is

The corresponding bit depth is N +1-i; b is _max Is the maximum actual brightness of the display moduleNit; n is the first bit depth, and i is an integer between 1 and N-2.

After the brightness interval and the corresponding bit depth are divided, the second bit depth is determined according to the current display brightness, and the original image signal is converted into the intermediate image signal based on the second bit depth.

According to the scheme, the division of the brightness intervals of the display modules with different types and different bit widths and the determination of the corresponding color depth are provided, and the image transmission power consumption of a signal source and the driving power consumption of the display module can be reduced when the display module is in a low-brightness state.

Taking an RGB image as an example, each pixel on the display module consists of three different sub-pixels: 5363 and R, G, B, the bit width of each sub-pixel in the original image is N, N is greater than or equal to 6, the value is usually 8 or 10, and the color depth of the corresponding image is 24bit or 30bit.

During conversion, the first data with N bits is shifted to the right by M bits aiming at each sub-pixel to obtain second data with N bits; n is a first bit depth, and M is a difference between the first bit depth and a second bit depth; removing M high-order values in the N bits of second data to obtain P bits of third data; obtaining an intermediate image signal based on the P-bit third data respectively corresponding to the plurality of sub-pixels; p is the second bit depth.

The method is to convert gray scale binary coding of pixels by a method of firstly shifting M bits to the right and then deleting M bits at high order. For example, the number of 8-bit gray levels is: 11110000, M =1, then right shift one bit becomes 01111000, then high order delete 1bit, only reserve 7 bits and then become 7bit coding: 1111000.

in combination with the above RGB image with a bit depth of 8bit and a color depth of 24bit, the corresponding conversion process is as follows:

when the brightness value of the full screen is adjusted to be N128-N255 by a user, the brightness is higher at the moment, and the data sent to the display module is unchanged and is an image signal with 8-bit depth and 24-bit color depth.

When a user adjusts the brightness value of the full screen to N64-N127, for 8-bit data of each color, the high bit is deleted for 1bit after the right bit is shifted for 1bit, only 7 bits are reserved, at the moment, the bit depth is 8 bits, the original image signal with the color depth of 24 bits is reduced to an intermediate image signal with the bit depth of 7 bits and the color depth of 21 bits; for example, the original 255 gray-level value is sent 127 after conversion, the original 254 gray-level value is sent 127, the original 253 gray-level value is sent 126, and so on.

When the user adjusts the brightness value of the full screen to N32-N63, for 8-bit data of each color, the high bit is deleted for 2 bits after right shifting for 2 bits, only 6 bits are reserved, at the moment, the bit depth is 8 bits, the original image signal with the color depth of 24 bits is reduced to the intermediate image signal with the bit depth of 6 bits and the color depth of 18 bits.

When the user adjusts the brightness value of the full screen to N16-N31, for 8-bit data of each color, 3 bits are deleted after shifting right by 3 bits, only 5 bits are reserved, at the moment, the bit depth is 8 bits, the original image signal with the color depth of 24 bits is reduced to an intermediate image signal with the bit depth of 5 bits and the color depth of 15 bits.

When the user adjusts the brightness value of the full screen to N8-N15, for 8-bit data of each color, the high bit is deleted 4 bits after right shifting 4 bits, only 4 bits are reserved, at the moment, the bit depth is 8 bits, the original image signal with the color depth of 24 bits is reduced to the intermediate image signal with the bit depth of 4 bits and the color depth of 12 bits.

When the brightness value of the full screen is adjusted to N4-N7 by a user, for 8-bit data of each color, 5 bits are deleted after the right shift by 5 bits, only 3 bits are reserved, at the moment, the bit depth is 8 bits, the original image signal with the color depth of 24 bits is reduced to an intermediate image signal with the bit depth of 3 bits and the color depth of 9 bits.

When the user adjusts the brightness value of the full screen to N0-N3, for 8-bit data of each color, the 6 bits are deleted after being shifted to the right by 6 bits, only 2 bits are reserved, at the moment, the bit depth is 8 bits, the original image signal with the color depth of 24 bits is reduced to the intermediate image signal with the bit depth of 2 bits and the color depth of 6 bits.

The corresponding relationship between the converted intermediate image signal and the brightness of the display module can be seen in fig. 5.

S103: sending the intermediate image signal to a display driving circuit so that the display driving circuit converts the intermediate image signal into a target image signal and outputs and displays the target image signal; the third bit depth of the target image signal is the same as the first bit depth.

Specifically, after receiving the intermediate image signal, the display driving circuit restores the intermediate image signal to the first color depth which is the same as that of the original image signal, and after the intermediate image signal is restored to the initial first color depth, the problem that the display effect of the display module is obviously reduced can be avoided, and the use experience of a user is guaranteed.

In contrast to the above method of changing from high to low, the display module converts the intermediate image signal into the target image signal as follows:

sending the intermediate image signal to a display driving circuit to cause the display driving circuit to perform:

supplementing a preset coding value to the coding tail of the third data aiming at the P-bit third data of each sub-pixel to obtain N-bit fourth data; and obtaining target image signals according to the N-bit fourth data respectively corresponding to the plurality of sub-pixels to output and display.

The conversion of the intermediate image signal into the target image signal may be performed by a Source Driver (Source Driver) of the display drive circuit, and the conversion process of the signal is as follows, corresponding to the foregoing example:

when the display module receives the intermediate image signal of 24 bits, the recovery is not needed.

When the display module receives the 21-bit intermediate image signal, for the 7-bit data of each color, 1-bit 0 (or 1) is supplemented at the end of encoding to change it into 8-bit data, for example, in the 7-bit data: the last bit of 1111000 is complemented by a bit of 0 to obtain 8-bit data: 11110000, so that the bit depth of the image is restored to 8 bits, and the color depth of the rgb image is restored to 24 bits.

When the display module receives 18-bit data, for 6-bit data of each color, the tail supplement of 2-bit 0 (or 1) is changed into 8-bit data, so that the bit depth of the image is restored to be 8bit, and the color depth of the RGB image is restored to be 24bit.

When the display module receives 15-bit data, for 5-bit data of each color, the tail supplement 3-bit 0 (or 1) is changed into 8-bit data, so that the bit depth of the image is restored to be 8bit, and the color depth of the RGB image is restored to be 24bit.

When the display module receives 12-bit data, for 4-bit data of each color, the tail supplementary 4-bit 0 (or 1) is changed into 8-bit data, so that the bit depth of the image is restored to be 8bit, and the color depth of the RGB image is restored to be 24bit.

When the display module receives 9-bit data, for 3-bit data of each color, the tail supplement 5-bit 0 (or 1) is changed into 8-bit data, so that the bit depth of the image is restored to be 8bit, and the color depth of the RGB image is restored to be 24bit.

When the display module receives 6-bit data, for 2-bit data of each color, the tail supplement 6-bit 0 (or 1) is changed into 8-bit data, so that the bit depth of the image is restored to be 8bit, and the color depth of the RGB image is restored to be 24bit.

The embodiment provides a display control method, which converts an original image with a first bit depth output to a display driving circuit of a display module into an intermediate image with a second bit depth according to the display brightness of the display module, wherein the first bit depth is greater than or equal to the second bit depth; the bit depth of the intermediate image is associated with the display brightness of the display module, and when the display brightness is reduced, the bit depth of the output original image is reduced, so that the image data volume transmitted from the signal source to the display driving circuit can be reduced, and the transmission power consumption of the image is reduced; through will show that luminance and second bit depth are positive correlation, when the luminance of display module assembly was lower promptly, the corresponding second bit depth was also lower, has still reduced the drive consumption of display drive circuit when low-luminance when reducing image signal transmission consumption. In addition, the display driving circuit converts the intermediate image with the second bit depth into a target image signal and outputs the target image signal after receiving the intermediate image with the second bit depth, and the third bit depth of the target image signal is the same as the first bit depth of the original image signal, so that the display quality of the display module under low brightness is not influenced.

Based on the same inventive concept, in a second aspect, please refer to fig. 6, in another alternative embodiment, a display device is provided, which includes a processor 1, a converter 5 and a display module 6; the converter 5 is connected between the processor 1 and the display module 6;

the converter 5 is used for: acquiring display brightness of a display module 6 and an original image signal output by a processor 1; converting the original image signal into an intermediate image signal according to the display brightness; and sending the intermediate image signal to the display module 6; the first bit depth of the original image signal is greater than or equal to the second bit depth of the intermediate image signal, and the display brightness is positively correlated with the second bit depth;

the display module 6 is used for: converting the intermediate image signal into a target image signal and outputting and displaying the target image signal; the third bit depth of the target image signal is the same as the first bit depth.

Specifically, the display device may be a display for a desktop computer, an all-in-one computer, a television, or a mobile electronic device such as a notebook computer, a tablet computer, and a smart phone.

The display device may include a signal source or an external signal source, the signal source may be a CPU, a GPU, a television box, or the like, and is configured to output an original image signal, and the processor 1 (CPU) is used as the signal source in this embodiment.

A converter 5 for converting an original image signal of high bit depth into an intermediate image signal of low bit depth, and fig. 6 shows an example of a converter 5 for reducing the bit depth of 8 bits to 2-8 bits, which forms with the processor 1 an output device capable of transmitting a light-dark image signal. Therefore, the converter 5 is connected to the processor 1 through a single line, and the processor 1 transmits a control signal to the converter 5 through a single line. In addition, the processor 1 capable of transmitting image signals of different color depths may also be used directly, i.e. the processor 1 is integrated with the converter 5.

The display module 6 in the display device may be an LCD display module or an OLED display module, taking an AMLCD display module as an example, the array substrate of the display module 6 may be implemented by using existing substrates of a-SI, LTPS, and the like, the backlight module 4 may also be implemented by using an existing commonly used implementation manner, and the backlight brightness of the backlight module 4 is controlled by the backlight control circuit 3. The display module 6 also needs to introduce a display driving circuit capable of receiving low bit depth (e.g. 2-8 bit) image signals. The display driving circuit may also be used to convert an image signal of low bit depth into an image signal of high bit depth, for example, by using a Source Driver 2 (Source Driver) in the display driving circuit, that is, the Source Driver 2 may be used to convert an intermediate image signal into a target image signal and output the target image signal for display.

The working process of the display device is as follows:

when detecting that a user reduces or adjusts display brightness, an original image signal sent to the source driver 2 by the processor 1 through the MIPI-DSI interface protocol may be reduced to an intermediate image signal of 2-8bit by the converter 5, after the source driver 2 receives the reduced intermediate image signal of 2-8bit, the original image signal may be restored to a target image signal of 8bit by high-order invariance, low-order complement of 0 (or low-order complement of 1) or other methods, and then converted and output a driving voltage by the digital-to-analog converter 5 (DAC) in the source driver 2, and the bit width of the target image signal received by the DAC of the source driver 2 is still 8bit. Compared with the original image signal, the compressed intermediate image signal is transmitted, although the restored 8-bit target image signal is simplified and discontinuous, because the display module 6 is at low brightness, the number of gray scales which can be distinguished by human eyes is obviously reduced, and therefore, the scheme does not cause the reduction of the display effect which can be obviously perceived. Therefore, under the condition of ensuring that the display effect perceived by the user is almost unchanged, the data volume sent to the source driver 2 by the processor 1 is reduced, the burden of image signal processing and the transmission power consumption of the image signals of the processor 1 are reduced, and the power consumption of the source driver 2 for receiving the image signals can be reduced.

In a third aspect, in another alternative embodiment, referring to fig. 7, there is provided a display control apparatus including:

an obtaining module 710, configured to obtain display brightness of the display module and an original image signal output to a display driving circuit of the display module;

a conversion module 720, configured to convert the original image signal into an intermediate image signal according to the display brightness; the first bit depth of the original image signal is greater than or equal to the second bit depth of the intermediate image signal, and the display brightness is positively correlated with the second bit depth;

a sending module 730, configured to send the intermediate image signal to the display driving circuit, so that the display driving circuit converts the intermediate image signal into a target image signal and outputs and displays the target image signal; the third bit depth of the target image signal is the same as the first bit depth.

Optionally, the converting module 720 is configured to:

determining a second bit depth according to the display brightness and a preset mapping relation between the display brightness and the bit depth;

the original image signal is converted into an intermediate image signal according to the second bit depth.

Optionally, the converting module 720 is configured to:

Optionally, the original image signal includes N bits of first data corresponding to the plurality of sub-pixels; the conversion module 720 is configured to:

for each sub-pixel, right shifting the N bits of first data by M bits to obtain N bits of second data; n is a first bit depth, and M is a difference between the first bit depth and a second bit depth; removing M high-bit values in the N-bit second data to obtain P-bit third data; obtaining an intermediate image signal based on the P-bit third data respectively corresponding to the plurality of sub-pixels; p is the second bit depth.

Optionally, the sending module 730 is configured to:

for the P-bit third data of each sub-pixel, supplementing a preset coding value to the coding end of the third data to obtain N-bit fourth data; and obtaining the target image signal according to the N bits of fourth data respectively corresponding to the plurality of sub-pixels to output and display.

It should be noted that the control device provided in the embodiment of the present invention, the specific implementation and the technical effects thereof are the same as those of the method embodiment of the first aspect, and for the sake of brief description, reference may be made to the corresponding contents in the foregoing method embodiment for the part where the embodiment of the device is not mentioned.

The term "and/or" appearing herein is merely one type of association that describes an associated object, meaning that three relationships may exist, e.g., a and/or B, may mean: a exists alone, A and B exist simultaneously, and B exists alone. In addition, the character "/" herein generally indicates that the former and latter related objects are in an "or" relationship; the word "comprising" does not exclude the presence of elements or steps not listed in a claim. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The invention may be implemented by means of hardware comprising several distinct elements, and by means of a suitably programmed computer. In the unit claims enumerating several means, several of these means may be embodied by one and the same item of hardware. The usage of the words first, second and third, etcetera do not indicate any ordering. These words may be interpreted as names.

As will be appreciated by one skilled in the art, embodiments of the present invention may be provided as a method, system, or computer program product. Accordingly, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present invention may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.

The present invention is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

While preferred embodiments of the present invention have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. Therefore, it is intended that the appended claims be interpreted as including preferred embodiments and all such alterations and modifications as fall within the scope of the invention.

It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is intended to include such modifications and variations.

Claims

1. A display control method, characterized in that the control method comprises:

2. The control method according to claim 1, wherein said converting the original image signal into an intermediate image signal according to the display luminance comprises:

3. The control method according to claim 1, wherein said converting the original image signal into an intermediate image signal according to the display luminance comprises:

4. The control method according to claim 3, wherein the preset plurality of luminance sections are obtained by dividing the preset plurality of luminance sections based on luminance values of 0 to 255, and the size of the luminance section is positively correlated with a luminance average value of the luminance sections.

5. The control method according to claim 4, wherein if the first bit depth is N, the number of the luminance sections is N-1, and the value range of the second bit depth is [2,N ]; n is an integer of 6 or more.

6. The control method according to claim 4, wherein the preset plurality of luminance sections include a first luminance section, a second luminance section, a third luminance section, a fourth luminance section, a fifth luminance section, a sixth luminance section, and a seventh luminance section;

7. The control method according to claim 1, wherein the original image signal includes N bits of first data corresponding to a plurality of sub-pixels; the converting the original image signal into an intermediate image signal according to the display brightness includes:

8. The method of claim 7, wherein sending the intermediate image signal to the display driver circuit to cause the display driver circuit to convert the intermediate image signal to a target image signal and output a display comprises:

9. A display control apparatus, characterized in that the control apparatus comprises:

the sending module is used for sending the intermediate image signal to the display driving circuit so that the display driving circuit converts the intermediate image signal into a target image signal and outputs and displays the target image signal; the third bit depth of the target image signal is the same as the first bit depth.

10. The display equipment is characterized by comprising a processor, a converter and a display module; the converter is connected between the processor and the display module;