Display control method, device and display equipment

Abstract

The present invention discloses a display control method, device and display equipment, wherein the control method includes: obtaining the display brightness of the display module and the original image signal output to the display driving circuit of the display module; according to the display brightness, converting the original image signal into an intermediate image signal; 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; 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 it for display; the third bit depth of the target image signal is the same as the first bit depth. This method can reduce the image signal transmission power consumption and the driving power consumption of the display driving circuit when the display module is at low brightness.

Description

Technical Field

[0001] The present application relates to the field of display technology, and in particular to a display control method, device and display equipment. Background Art

[0002] When using a display or an electronic device equipped with a display, it is usually necessary to adjust the brightness of the display. For example, current smartphones have the function of automatically adjusting the brightness according to the environment, and also the function of manually adjusting the brightness according to the user's instructions. Figure 1 , slide the brightness control bar by gesture, and the screen brightness will change accordingly.

[0003] Currently, displays or electronic devices are often equipped with liquid crystal displays, such as AMLCD (Active Matrix Liquid Crystal Display) as display screens. For brightness control, please refer to the principle of Figure 2 The display driver circuit 2' of the display is connected to the signal source 1', such as the CPU or GPU, through a data line, and the backlight driver circuit 3' is connected to the signal source 1' through a single-wire. The signal source 1' sends an image signal to the display driver circuit 2' and sends a control command to the backlight driver circuit 3' to adjust the brightness of the backlight module 4', such as a light-emitting diode (LED). The backlight driver circuit 3' can use two methods to control the brightness change: one is "DC dimming". DC dimming changes the brightness of the screen by increasing or decreasing the current of the LED; after the LED is turned on, its brightness is basically proportional to the current, so the brightness of the display can be changed by changing the current; the other is PWM dimming, which is not achieved by changing the power during PWM dimming, but by controlling the alternation of the display screen on and off; in the process of the screen turning on and off, the longer the screen off state lasts, the lower the brightness of the screen to the naked eye; the longer the lighting time, the shorter the screen off time, and the brighter the screen.

[0004] The problem with the above display brightness control method is that when the user lowers the display brightness, although the power of the backlight module decreases, the image transmission power consumption of the display does not change compared to when the display is at high brightness, thus generating unnecessary power consumption loss. Summary of the invention

[0005] The present invention provides a display control method, device and display equipment, which can reduce the image transmission power consumption of a display module at low brightness.

[0006] In the first aspect, the present application provides the following technical solution through an embodiment:

[0007] A display control method, comprising:

[0008] Acquiring the display brightness of the display module and the original image signal output to the display driving circuit of the display module;

[0009] According to the display brightness, converting the original image signal into an intermediate image signal; 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;

[0010] The intermediate image signal is sent to the display driving circuit, so that the display driving circuit converts the intermediate image signal into a target image signal and outputs it for display; the third bit depth of the target image signal is the same as the first bit depth.

[0011] Optionally, converting the original image signal into an intermediate image signal according to the display brightness includes:

[0012] Determining the second bit depth according to the display brightness and a preset mapping relationship between display brightness and bit depth;

[0013] The original image signal is converted into the intermediate image signal according to the second bit depth.

[0014] Optionally, converting the original image signal into an intermediate image signal according to the display brightness includes:

[0015] According to the display brightness, determining a target brightness interval to which the display brightness belongs from a plurality of preset brightness intervals; each of the brightness intervals corresponds to a bit depth;

[0016] The original image signal is converted into an intermediate image signal according to the bit depth of the target brightness range; the second bit depth is the bit depth of the target brightness range.

[0017] Optionally, the preset multiple brightness intervals are obtained by dividing based on brightness values ​​of 0 to 255, and the size of the brightness interval is positively correlated with the brightness mean value of the brightness interval.

[0018] Optionally, if the first bit depth is N, the number of the brightness intervals is N-1, and the value range of the second bit depth is [2, N]; N is an integer greater than or equal to 6.

[0019] Optionally, the preset multiple brightness intervals include a first brightness interval, a second brightness interval, a third brightness interval, a fourth brightness interval, a fifth brightness interval, a sixth brightness interval and a seventh brightness interval;

[0020] The first brightness range is [0,3], and the bit depth corresponding to the first brightness range is 2;

[0021] The second brightness range is [4,7], and the bit depth corresponding to the second brightness range is 3;

[0022] The third brightness range is [8, 15], and the bit depth corresponding to the third brightness range is 4;

[0023] The fourth brightness range is [16, 31], and the bit depth corresponding to the fourth brightness range is 5;

[0024] The fifth brightness range is [32, 63], and the bit depth corresponding to the fifth brightness range is 6;

[0025] The sixth brightness range is [64, 127], and the bit depth corresponding to the sixth brightness range is 7;

[0026] The seventh brightness range is [128, 255], and the bit depth corresponding to the seventh brightness range is 8.

[0027] Optionally, the original image signal includes N-bit first data corresponding to a plurality of sub-pixels; and converting the original image signal into an intermediate image signal according to the display brightness includes:

[0028] For each of the sub-pixels, right-shift the N-bit first data by M bits to obtain N-bit second data, where N is the first bit depth, and M is the difference between the first bit depth and the second bit depth;

[0029] Remove M high-order values ​​from the N-bit second data to obtain P-bit third data;

[0030] The intermediate image signal is obtained based on P-bit third data corresponding to each of the plurality of sub-pixels; P is the second bit depth.

[0031] Optionally, 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 the target image signal for display includes:

[0032] The intermediate image signal is sent to the display driving circuit so that the display driving circuit performs:

[0033] For each of the P-bit third data of the sub-pixel, a preset coding value is added to the end of the coding of the third data to obtain the N-bit fourth data;

[0034] The target image signal is obtained according to the N-bit fourth data respectively corresponding to the plurality of sub-pixels to output for display.

[0035] In the second aspect, based on the same inventive concept, the present application provides the following solution through an embodiment:

[0036] A display control device, comprising:

[0037] An acquisition module, used to acquire the display brightness of the display module and the original image signal output to the display driving circuit of the display module;

[0038] a conversion module, configured to convert the original image signal into an intermediate image signal according to the display brightness; a first bit depth of the original image signal being greater than or equal to a second bit depth of the intermediate image signal, and the display brightness being positively correlated with the second bit depth;

[0039] A sending module is used 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 it for display; the third bit depth of the target image signal is the same as the first bit depth.

[0040] In the third aspect, based on the same inventive concept, the present application provides the following solution through an embodiment:

[0041] A display device, comprising a processor, a converter and a display module; the converter is connected between the processor and the display module;

[0042] The converter is used to: obtain the display brightness of the display module and the original image signal output by the processor; convert the original image signal into an intermediate image signal according to the display brightness; and send the intermediate image signal to the display module; 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;

[0043] The display module is used to: convert the intermediate image signal into a target image signal and output it for display; the third bit depth of the target image signal is the same as the first bit depth.

[0044] Through one or more technical solutions of the present invention, the present invention has the following beneficial effects or advantages:

[0045] The present invention 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; by associating the bit depth of the intermediate image with the display brightness of the display module, when the display brightness is reduced, the bit depth of the output original image is reduced, thereby reducing the amount of image data transmitted from the signal source to the display driving circuit, and reducing the transmission power consumption of the image; by positively correlating the display brightness with the second bit depth, that is, when the brightness of the display module is low, the corresponding second bit depth is also low, while reducing the transmission power consumption of the image signal, the driving power consumption of the display driving circuit at low brightness is also reduced. In addition, after receiving the intermediate image with the second bit depth, the display driving circuit converts it into a target image signal and outputs it, and the third bit depth of the target image signal is the same as the first bit depth of the original image signal, thereby not affecting the display quality of the display module at low brightness.

[0046] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented according to the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present invention. Moreover, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0048] Figure 1 A schematic diagram showing a current method of adjusting brightness in an electronic device;

[0049] Figure 2 A schematic diagram showing the brightness control principle of a current display is shown;

[0050] Figure 3 A schematic diagram of a display control method according to an embodiment of the present invention is shown;

[0051] Figure 4 A schematic diagram showing a dimming implementation method of a display according to an embodiment of the present invention is shown;

[0052] Figure 5 A schematic diagram showing a corresponding relationship between the bit depth of an image signal and display brightness according to an embodiment of the present invention is shown;

[0053] Figure 6 A schematic diagram of a display device according to an embodiment of the present invention is shown;

[0054] Figure 7 A schematic diagram of a display control device according to an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0055] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0056] Currently, LCD liquid crystal displays are commonly used in various types of displays and electronic devices. Liquid crystal is a type of organic compound between solid and liquid. At room temperature, it exhibits both the fluidity of liquid and the optical anisotropy of crystal. When heated, it will become a transparent liquid, and when cooled, it will become a crystalline turbid solid.

[0057] Under the action of the electric field, the arrangement of liquid crystal molecules will change, thus affecting the intensity of the incident light beam passing through the liquid crystal. This change in light intensity is further manifested as a change in brightness through the action of the polarizer. Based on this, the brightness and darkness of the light can be changed by controlling the electric field of the liquid crystal, thereby achieving the purpose of information display. Therefore, the role of liquid crystal materials is similar to that of small "light valves".

[0058] Because there are control circuits and drive circuits around the liquid crystal material, when the electrodes in the LCD generate an electric field, the liquid crystal molecules will be twisted, thereby refracting the light passing through them in a regular manner (the optical rotation of the liquid crystal material), and then being filtered by the second layer of polarizer and displayed on the screen.

[0059] Because liquid crystal materials do not emit light themselves, LCDs usually require additional light sources for the display panel. The main light source system is called a "backlight module". Currently, most backlight modules use light-emitting diodes (LEDs).

[0060] After analysis, it was found that for current displays, especially backlit AMLCD displays, when users lower the display brightness, although the current of the LED in the backlight module decreases and the power is reduced, the color depth of the image data received by the display driver chip (IC) in the display remains unchanged, and the transmission power consumption of all images does not change when the display is at high brightness. Studies have shown that when the screen brightness is maximum, the number of grayscales that the human eye can perceive can be divided into approximately 256 levels (8-bit color depth), and when the brightness decreases, the number of grayscales that the human eye can perceive will decrease rapidly. When the screen is at the lowest brightness, the number of grayscales that the human eye can perceive is even less than 10. However, at this time, the signal source of the display (such as the CPU in the mobile phone, the GPU in the computer) is still sending 256 levels (8-bit color depth) of data to the display. At this time, a large amount of data cannot be perceived by the human eye, and the large amount of data sent at this time means greater image transmission power consumption, so some power consumption can be saved when the display is at low brightness.

[0061] Based on the above reasons, the present invention is proposed to solve the problem of high power consumption of image transmission when the display is at low brightness. In a first aspect, a display control method is provided in an optional embodiment, referring to FIG. 3 , including steps S101 to S103, which are as follows:

[0062] S101: Obtain the display brightness of the display module and the original image signal output to the display driving circuit of the display module; specifically, the original image signal is the image data sent by the signal source to the display driving circuit of the display module, such as the image data sent by the CPU, GPU, etc. of the electronic device to the display driving circuit of the display module. The display module may be a display screen of a mobile phone, a computer display module, a display screen of a tablet computer, and so on. It can be understood that the display module may include a display driving circuit and a display panel. The display panel may be an existing commonly used display panel, and the type is not limited. For example, when it is an LCD panel, it may be composed of a backlight module, an array substrate, a color film substrate, etc. The specific structure can be understood by referring to the prior art and will not be repeated here. The display driving circuit may include but is not limited to a gate driver, a source driver, and a TCON (timing controller).

[0063] Luminance is a property of color, or a dimension of color space that is related to the brightness of a color. In the Lab color space, luminance is defined to reflect the subjective perception of brightness by humans.

[0064] For display modules, brightness refers to the brightness of the picture, and the unit is candela per square meter (cd / m 2) or nits, which is candlelight per square meter. There are currently two ways to increase the brightness of display screens. One is to increase the light transmittance of the LCD panel; the other is to increase the brightness of the backlight module. Currently, in terms of LCD brightness research, it has reached 800nits or even higher.

[0065] In the field of computer graphics, a grayscale digital image is an image with only one sampled color per pixel. Such images are usually displayed as grayscale from the darkest black to the brightest white, although in theory this sample can represent different shades of any color, or even different colors at different brightnesses. Grayscale images are different from black and white images. In the field of computer graphics, black and white images only have two colors, black and white, while grayscale images have many levels of color depth between black and white. However, outside the field of digital images, "black and white images" also mean "grayscale images", for example, grayscale photos are usually called "black and white photos". In some articles about digital images, monochrome images are equivalent to grayscale images, and in other articles they are equivalent to black and white images. In the field of display, the so-called color or grayscale refers to the difference in brightness of the pixels displayed in a black and white display module, which is manifested as different colors in a color display module. The more grayscale levels there are, the clearer and more realistic the image layers are. The grayscale level depends on the number of bits of the refresh storage unit corresponding to each pixel and the performance of the display module itself.

[0066] S102: converting the original image signal into an intermediate image signal according to 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.

[0067] In the field of digital images, the color depth and bit depth of an image are different concepts. Color depth refers to the "depth of color". In digital images, the smallest unit is a 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 image, which can express 2 to the 16th power, that is, 65,536 colors; if each pixel is represented by a 24-bit binary number, it is called a 24-bit image, which can express 2 to the 24th power, that is, 16,777,216 colors. Each pixel has independent parameters. Taking an RGB three-channel image as an example, each pixel consists of three channels, R, G, and B, and each channel is represented by a number of binary bits to represent its "content". For example, 11001101100110011111111 (24-bit image) means 102 red, 204 green, and 255 blue. According to the additive color theory, this color is "sky blue". Therefore, "color depth" is used to represent the binary digits of the color, that is, 24 bits. In addition, although many digital images are not represented by RGB but by YUV, the parameter description of color depth is the same.

[0068] The concept of bit depth is relatively broad, and can be used to describe the accuracy of quantizing analog signals or simulating digital signals. In the display or image fields, the most basic unit of display module display is the dot, and the number of pulse signal bits used to describe the brightness of each dot is called "bit depth."

[0069] Therefore, in the display field, bit depth can be understood as bits per channel, that is, channel bit depth, and color depth can be understood as bits per pixel. For RGB images, the bit depth is the bit width of each channel, such as 8 bits, and color depth = the sum of the bit depths of the three channels, that is, 24 bits.

[0070] The relationship between the color depth and bit depth of common digital images is as follows:

[0071] Color depth: 18bit (RGB / YUV), bit depth 6bit;

[0072] Color depth: 24bit (RGB / YUV), bit depth 8bit;

[0073] Color depth: 30bit (RGB / YUV), bit depth 10bit;

[0074] Color depth: 32bit (RGBA), bit depth 8bit;

[0075] Color depth: 40bit (RGBA / YUVA), bit depth is 10bit.

[0076] Step S102 of this embodiment is to adjust the bit depth of the original image signal according to the current display brightness of the display module. When the display brightness is reduced, the bit depth of the original image signal is reduced, thereby synchronously reducing the color depth of the original image, thereby achieving the purpose of reducing the amount of data transmitted from the signal source to the display driving circuit of the display module.

[0077] The display brightness is positively correlated with the second bit depth, which means that as the display brightness decreases, the value of the second bit depth decreases. The positive correlation may be a linear correlation, or an exponential correlation, a polynomial correlation, etc. In addition, the positive correlation may be that one display brightness value corresponds to one second bit depth (one-to-one), or multiple display brightness values ​​correspond to one second bit depth (many-to-one), which is not limited here.

[0078] Then, converting the original image signal into an intermediate image signal according to the display brightness means converting the original image signal with the first bit depth into an intermediate image signal with the second bit depth according to the current display brightness, thereby reducing the color depth of the image signal and the amount of data transmission. The first bit depth is the bit depth of the image signal output by the signal source. For the display module, the commonly used image signal bit depths are 8bit and 10bit. The pixels are composed of RGB, so the corresponding image color depths are 24bbit and 30bit.

[0079] According to the display brightness, the schemes that can be used to convert the original image signal into the intermediate image signal may include:

[0080] Solution 1: Determine the second bit depth according to the display brightness and the preset mapping relationship between the display brightness and the bit depth; and convert the original image signal into an intermediate image signal according to the second bit depth.

[0081] Specifically, the mapping relationship can be a functional relationship between display brightness and bit depth, or a corresponding relationship table between display brightness and bit depth. If it is a functional relationship, the display brightness is used as an independent variable to input the functional relationship to obtain the corresponding bit depth; if it is a corresponding relationship table, the display brightness can be used to look up the table to obtain the corresponding bit depth.

[0082] Solution 2: According to the display brightness, determine the target brightness interval to which the display brightness belongs from multiple preset brightness intervals; each brightness interval corresponds to a bit depth; according to the bit depth of the target brightness interval, convert the original image signal into an intermediate image signal; the second bit depth is the bit depth of the target brightness interval.

[0083] Specifically, through research, the brightness range of the display module can be divided into multiple brightness intervals in advance, and then a corresponding bit depth can be determined for each brightness interval. The range and number of brightness intervals can be determined according to the grayscale number of the color channel or the brightness range of the display module. After obtaining the current display brightness of the display module, the brightness interval to which the current display brightness belongs can be clearly determined, thereby quickly determining the second bit depth corresponding to the current display brightness.

[0084] The actual brightness of the display module screen (in nit) is related to two parameters: one is the brightness control bar adjusted by the user through gestures or controllers when operating the display module or an electronic device with the display module. For LCD displays, the brightness control bar adjusts the brightness value of the backlight module; if it is a display without a backlight module such as OLED (organic light emitting diode), it adjusts the full-screen brightness value; the second is the grayscale number or grayscale value. For an 8-bit wide display, the grayscale number divides the screen transmittance into 256 levels, and the grayscale value of each pixel is individually controllable.

[0085] For example, if an LCD display uses a 10000nit backlight module and the maximum pass rate is 10%, the brightness can be 1000nit at 256 grayscale and 300nit at 128 grayscale. If the backlight is adjusted to 1000nit, the brightness can be 100nit at 256 grayscale and 30nit at 128 grayscale.

[0086] Since different screens have different display brightness ranges, when implementing the program, in order to universalize the control, the display brightness range of the screen can be unified to the brightness value range of [N0, N255]. Therefore, the preset multiple brightness intervals are obtained based on the brightness value of 0 to 255, and the size of the brightness interval is positively correlated with the brightness mean of the brightness interval.

[0087] The size of the brightness interval is positively correlated with the average brightness of the brightness interval, which means that the range of different brightness intervals is not uniform, but meets the rule that the smaller the brightness value, the smaller the distance between the upper and lower limits of the corresponding brightness interval, and the larger the brightness value, the larger the distance between the upper and lower limits of the corresponding brightness interval. The principle of this setting is to take into account that the grayscale value of the sub-pixel RGB and the display brightness of the display module are not a simple linear relationship, but a power function relationship, such as Figure 4As shown. The exponent of the power function is called the Gamma value, which is generally 2.2. This conversion process is called Gamma correction. Therefore, by making the size of the brightness interval positively correlated with the brightness mean of the brightness interval, it can ensure that the adjustment range of the second bit depth is more matched with the change in the actual brightness of the display module, while reducing the power consumption of image signal transmission and ensuring that the display quality of the display module will not be significantly reduced.

[0088] The number of brightness intervals 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 brightness intervals is N-1, and the value range of the second bit depth is [2, N]; N ≥ 6 and is an integer.

[0089] The bit width of common display modules is 8 bits or 10 bits, that is, the bit width of the original image signal is 8 bits or 10 bits. Let's take these as examples:

[0090] For 8bit: Seven brightness ranges can be preset, as follows:

[0091] The first brightness range is [0,3], and the bit depth corresponding to the first brightness range is 2;

[0092] The second brightness range is [4,7], and the bit depth corresponding to the second brightness range is 3;

[0093] The third brightness range is [8,15], and the bit depth corresponding to the third brightness range is 4;

[0094] The fourth brightness range is [16,31], and the bit depth corresponding to the fourth brightness range is 5;

[0095] The fifth brightness range is [32,63], and the bit depth corresponding to the fifth brightness range is 6;

[0096] The sixth brightness range is [64,127], and the bit depth corresponding to the sixth brightness range is 7;

[0097] The seventh brightness range is [128, 255], and the bit depth corresponding to the seventh brightness range is 8.

[0098] For 10bit: 9 brightness ranges can be preset, as follows:

[0099] The first brightness range is [0,1], and the bit depth corresponding to the first brightness range is 2;

[0100] The second brightness range is [1,3], and the bit depth corresponding to the second brightness range is 3;

[0101] The third brightness range is [4,7], and the bit depth corresponding to the third brightness range is 4;

[0102] The fourth brightness range is [8,15], and the bit depth corresponding to the fourth brightness range is 5;

[0103] The fifth brightness range is [16,31], and the bit depth corresponding to the fifth brightness range is 6;

[0104] The sixth brightness range is [32,64], and the bit depth corresponding to the sixth brightness range is 7;

[0105] The seventh brightness range is [64,127], and the bit depth corresponding to the seventh brightness range is 8.

[0106] The eighth brightness range is [128,191], and the bit depth corresponding to the eighth brightness range is 9;

[0107] The ninth brightness range is [192,255], and the bit depth corresponding to the ninth brightness range is 10.

[0108] In some embodiments, the division of brightness intervals may also take into account the actual brightness value (nit) of the display module, and the following scheme may be adopted:

[0109] If the brightness range is The corresponding bit depth is 2;

[0110] If the display interval is The corresponding bit depth is N+1-i; B max It is the maximum actual brightness of the display module, in nit; N is the first bit depth, and i is an integer between 1 and N-2.

[0111] After the brightness intervals and the corresponding bit depths are divided, the next step is to determine the second bit depth according to the current display brightness, and convert the original image signal into an intermediate image signal based on the second bit depth.

[0112] The above scheme provides a method for dividing the brightness ranges of display modules of different types and different bit widths and determining the corresponding color depths. It can also reduce the image transmission power consumption of the signal source and the driving power consumption of the display module when the display module is in a low brightness state.

[0113] Taking RGB images as an example, each pixel on the display module is composed of three different sub-pixels: R, G, and B. Let the bit width of each sub-pixel in the original image be N, N ≥ 6, and the common values ​​are 8 or 10, and the corresponding image color depth is 24bit or 30bit.

[0114] During the conversion, for each sub-pixel, the N-bit first data is right-shifted by M bits to obtain the N-bit second data; N is the first bit depth, and M is the difference between the first bit depth and the second bit depth; the M high-bit values ​​in the N-bit second data are removed to obtain the P-bit third data; based on the P-bit third data corresponding to multiple sub-pixels, an intermediate image signal is obtained; P is the second bit depth.

[0115] The above method is to convert the grayscale binary encoding of the pixel by first shifting right by M bits and then deleting M bits in the high position. For example, if the grayscale number of an 8-bit pixel is: 11110000, M=1, then shifting right by one bit becomes 01111000, and then deleting one bit in the high position, leaving only 7 bits, and then becoming a 7-bit encoding: 1111000.

[0116] Combining the above content with the example of 8-bit RGB image with 24-bit color depth, the corresponding conversion process is as follows:

[0117] When the user adjusts the full-screen brightness value to N128-N255, the brightness is relatively high, and the data sent to the display module remains unchanged, which is an image signal with an 8-bit bit depth and a 24-bit color depth.

[0118] When the user adjusts the full-screen brightness value to N64-N127, for the 8-bit data of each color, after shifting right by 1 bit, the high bit is deleted and only 7 bits are retained. At this time, the original image signal with a bit depth of 8 bits and a color depth of 24 bits is reduced to an intermediate image signal with a bit depth of 7 bits and a color depth of 21 bits; for example, after conversion, the original 255 grayscale value is sent as 127, the original 254 grayscale value is sent as 127, the original 253 grayscale value is sent as 126, and so on.

[0119] When the user adjusts the full-screen brightness value to N32-N63, for the 8-bit data of each color, the high-order 2 bits are deleted after right shifting 2 bits, leaving only 6 bits. At this time, the original image signal with a bit depth of 8 bits and a color depth of 24 bits is reduced to an intermediate image signal with a bit depth of 6 bits and a color depth of 18 bits.

[0120] When the user adjusts the full-screen brightness value to N16-N31, for the 8-bit data of each color, the high-order 3 bits are deleted after right shifting 3 bits, leaving only 5 bits. At this time, the original image signal with a bit depth of 8 bits and a color depth of 24 bits is reduced to an intermediate image signal with a bit depth of 5 bits and a color depth of 15 bits.

[0121] When the user adjusts the full-screen brightness value to N8-N15, for the 8-bit data of each color, the high-order 4 bits are deleted after right shifting 4 bits, leaving only 4 bits. At this time, the original image signal with a bit depth of 8 bits and a color depth of 24 bits is reduced to an intermediate image signal with a bit depth of 4 bits and a color depth of 12 bits.

[0122] When the user adjusts the full-screen brightness value to N4-N7, for the 8-bit data of each color, the 5 high bits are deleted after right shifting 5 bits, leaving only 3 bits. At this time, the original image signal with a bit depth of 8 bits and a color depth of 24 bits is reduced to an intermediate image signal with a bit depth of 3 bits and a color depth of 9 bits.

[0123] When the user adjusts the full-screen brightness value to N0-N3, for the 8-bit data of each color, the high-order 6 bits are deleted after right shifting 6 bits, leaving only 2 bits. At this time, the original image signal with a bit depth of 8 bits and a color depth of 24 bits is reduced to an intermediate image signal with a bit depth of 2 bits and a color depth of 6 bits.

[0124] The corresponding relationship between the converted intermediate image signal and the brightness of the display module can be found in Figure 5 .

[0125] 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 it for display; the third bit depth of the target image signal is the same as the first bit depth.

[0126] Specifically, after receiving the intermediate image signal, the display driving circuit restores it to the same first color depth as the original image signal. After restoring the intermediate image to the initial first color depth, the problem of significantly reduced display effect of the display module can be avoided, thereby ensuring the user experience.

[0127] In contrast to the above-mentioned high-bit to low-bit conversion method, the display module has the following optional solutions for converting the intermediate image signal into the target image signal:

[0128] The intermediate image signal is sent to the display driving circuit so that the display driving circuit performs:

[0129] For the P-bit third data of each sub-pixel, a preset coding value is added to the end of the coding of the third data to obtain N-bit fourth data; according to the N-bit fourth data corresponding to multiple sub-pixels, a target image signal is obtained for output display.

[0130] The work of converting the intermediate image signal into the target image signal can be performed by the source driver of the display driving circuit. Corresponding to the above example, the signal conversion process is as follows:

[0131] When the display module receives a 24-bit intermediate image signal, no recovery is required.

[0132] When the display module receives the 21-bit intermediate image signal, for the 7-bit data of each color, a 0 (or 1) is added to the end of the encoding to convert it into 8-bit data. For example, a 0 is added to the last bit of the 7-bit data: 1111000 to obtain 8-bit data: 11110000, thereby restoring the image bit depth to 8 bits and the RGB image color depth to 24 bits.

[0133] When the display module receives 18-bit data, 2 bits of 0 (or 1) are added to the end of the 6-bit data of each color to convert it into 8-bit data, so that the image bit depth is restored to 8 bits and the color depth of the RGB image is restored to 24 bits.

[0134] When the display module receives 15-bit data, 3 bits of 0 (or 1) are added to the end of the 5-bit data of each color to convert it into 8-bit data, so that the image bit depth is restored to 8 bits and the color depth of the RGB image is restored to 24 bits.

[0135] When the display module receives 12-bit data, 4 bits of 0 (or 1) are added to the end of the 4-bit data of each color to convert it into 8-bit data, so that the image bit depth is restored to 8 bits and the color depth of the RGB image is restored to 24 bits.

[0136] When the display module receives 9-bit data, it adds 5 bits of 0 (or 1) at the end of the 3-bit data of each color to convert it into 8-bit data, so that the image bit depth is restored to 8 bits and the color depth of the RGB image is restored to 24 bits.

[0137] When the display module receives 6-bit data, for each color's 2-bit data, 6 bits of 0 (or 1) are added to the end to convert it into 8-bit data, so that the image bit depth is restored to 8 bits and the color depth of the RGB image is restored to 24 bits.

[0138] This embodiment provides a display control method, by converting the original image with a first bit depth output to the display driving circuit of the 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; by associating the bit depth of the intermediate image with the display brightness of the display module, when the display brightness is reduced, the bit depth of the output original image is reduced, so that the amount of image data transmitted from the signal source to the display driving circuit can be reduced, and the transmission power consumption of the image is reduced; by making the display brightness positively correlated with the second bit depth, that is, when the brightness of the display module is low, the corresponding second bit depth is also low, while reducing the transmission power consumption of the image signal, the driving power consumption of the display driving circuit at low brightness is also reduced. In addition, after receiving the intermediate image with the second bit depth, the display driving circuit converts it into a target image signal and outputs it, 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 at low brightness is not affected.

[0139] Based on the same inventive concept, in the second aspect, please refer to Figure 6 In another optional embodiment, a display device is provided, the display device comprising 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;

[0140] The converter 5 is used to: obtain the display brightness of the display module 6 and the original image signal output by the processor 1; convert the original image signal into an intermediate image signal according to the display brightness; and send 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;

[0141] The display module 6 is used to convert the intermediate image signal into a target image signal and output the target image signal for display; the third bit depth of the target image signal is the same as the first bit depth.

[0142] Specifically, the display device may be a monitor for a desktop computer, an all-in-one computer, a television, etc., or may be a mobile electronic device such as a laptop computer, a tablet computer, a smart phone, etc.

[0143] The display device may include a signal source or an external signal source. The signal source may be a CPU, a GPU or a TV box, etc., for outputting original image signals. In this embodiment, the processor 1 (CPU) is used as the signal source.

[0144] The converter 5 is used to convert the original image signal with a high bit depth into an intermediate image signal with a low bit depth. Figure 6An example of a converter 5 that reduces the bit depth of 8 bits to 2 to 8 bits is shown, and the converter 5 and the processor 1 form an output device capable of sending a light color depth image signal. Therefore, the converter 5 is connected to the processor 1 via a single-wire, and the processor 1 sends a control signal to the converter 5 via the single-wire. In addition, the processor 1 that can send image signals of different color depths can also be used directly, that is, the processor 1 is integrated with the converter 5.

[0145] The display module 6 in the display device can be an LCD display module or an OLED display module. Taking the AMLCD display module as an example, the array substrate of the display module 6 can be implemented by using existing a-SI, LTPS and other types of substrates. The backlight module 4 can also adopt the existing commonly used implementation method. 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 driver circuit that can receive low-bit depth (such as 2 to 8 bits) image signals. The display driver circuit can also be used to convert low-bit depth image signals into high-bit depth image signals, for example, using the source driver 2 (Source Driver) in the display driver circuit. That is, the source driver 2 can be used to convert the intermediate image signal into a target image signal and output it for display.

[0146] The working process of the display device is:

[0147] When it is detected that the user reduces or adjusts the display brightness, the original image signal sent by the processor 1 to the source driver 2 through the MIPI-DSI interface protocol can be reduced to an intermediate image signal of 2 to 8 bits through the converter 5. After receiving the reduced intermediate image signal of 2-8 bits, the source driver 2 can restore it to an 8-bit target image signal by keeping the high bit unchanged, filling the low bit with 0 (or filling the low bit with 1) or other methods, and then convert it through the digital-to-analog converter 5 (DAC) in the source driver 2 and output the driving voltage. The bit width of the target image signal received by the DAC of the source driver 2 is still 8 bits. Compared with the original image signal, the compressed intermediate image signal is transmitted, and although the restored 8-bit target image signal is simplified and discontinuous, because the display module 6 is at low brightness at this time, the number of grayscales that the human eye can distinguish has been significantly reduced. Therefore, the above scheme does not cause a significant decrease in the display effect that can be perceived. Thereby, while ensuring that the display effect perceived by the user remains almost unchanged, the amount of data sent by the processor 1 to the source driver 2 is reduced, which not only reduces the burden of image signal processing on the processor 1 and the power consumption of image signal transmission, but also reduces the power consumption of the source driver 2 in receiving image signals.

[0148] In another optional embodiment, please refer to Figure 7 , provides a display control device, comprising:

[0149] An acquisition module 710 is used to acquire the display brightness of the display module and the original image signal output to the display driving circuit of the display module;

[0150] A conversion module 720, configured to convert the original image signal into an intermediate image signal according to 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;

[0151] The sending module 730 is used 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 it for display; the third bit depth of the target image signal is the same as the first bit depth.

[0152] Optionally, the conversion module 720 is used to:

[0153] Determining a second bit depth according to the display brightness and a preset mapping relationship between the display brightness and the bit depth;

[0154] The original image signal is converted into an intermediate image signal according to the second bit depth.

[0155] Optionally, the conversion module 720 is used to:

[0156] According to the display brightness, determining a target brightness interval to which the display brightness belongs from a plurality of preset brightness intervals; each brightness interval corresponds to a bit depth;

[0157] The original image signal is converted into an intermediate image signal according to the bit depth of the target brightness range; the second bit depth is the bit depth of the target brightness range.

[0158] Optionally, the original image signal includes N-bit first data corresponding to a plurality of sub-pixels; the conversion module 720 is used for:

[0159] For each sub-pixel, the N-bit first data is right shifted by M bits to obtain the N-bit second data; N is the first bit depth, and M is the difference between the first bit depth and the second bit depth; the M high-bit values ​​in the N-bit second data are removed to obtain the P-bit third data; based on the P-bit third data corresponding to multiple sub-pixels, an intermediate image signal is obtained; P is the second bit depth.

[0160] Optionally, the sending module 730 is used to:

[0161] The intermediate image signal is sent to the display driving circuit so that the display driving circuit performs:

[0162] For the P-bit third data of each sub-pixel, a preset coding value is supplemented at the end of the encoding of the third data to obtain the N-bit fourth data; based on the N-bit fourth data corresponding to the multiple sub-pixels, the target image signal is obtained for output display.

[0163] It should be noted that the specific implementation and technical effects of the control device provided in the embodiment of the present invention are the same as those of the method embodiment of the first aspect. For the sake of brief description, for matters not mentioned in the device embodiment, reference may be made to the corresponding contents in the aforementioned method embodiment.

[0164] The term "and / or" that appears in this article is only a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the objects associated before and after are in an "or" relationship; the word "comprising" does not exclude the existence of elements or steps that are not listed in the claims. The word "one" or "an" placed before an element does not exclude the existence of multiple such elements. The present invention can be implemented with the aid of hardware including several different elements and with the aid of appropriately programmed computers. In a unit claim that lists several devices, several of these devices may be embodied by the same hardware item. The use of the words first, second, and third, etc. does not indicate any order. These words can be interpreted as names.

[0165] It will be appreciated by those skilled in the art that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0166] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1A device that provides the functions specified in a block or multiple blocks.

[0167] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 One or more processes and / or boxes Figure 1 A function specified in one or more boxes.

[0168] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0169] Although the preferred embodiments of the present invention have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0170] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these 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 also intended to include these modifications and variations.

Claims

1. A display control method, It is characterized in that The control method comprises: Acquiring the display brightness of the display module and the original image signal output to the display driving circuit of the display module; According to the display brightness, converting the original image signal into an intermediate image signal; 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 intermediate image signal is sent to the display driving circuit, so that the display driving circuit converts the intermediate image signal into a target image signal and outputs it for display; the third bit depth of the target image signal is the same as the first bit depth.

2. The control method according to claim 1, It is characterized in that 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 relationship between display brightness and bit depth; The original image signal is converted into the intermediate image signal according to the second bit depth.

3. The control method according to claim 1, It is characterized in that The converting the original image signal into an intermediate image signal according to the display brightness includes: According to the display brightness, determining a target brightness interval to which the display brightness belongs from a plurality of preset brightness intervals; each of the brightness intervals corresponds to a bit depth; The original image signal is converted into an intermediate image signal according to the bit depth of the target brightness range; the second bit depth is the bit depth of the target brightness range.

4. The control method according to claim 3, It is characterized in that The preset multiple brightness intervals are obtained by dividing based on brightness values ​​of 0 to 255, and the size of the brightness interval is positively correlated with the brightness mean value of the brightness interval.

5. The control method according to claim 4, It is characterized in that If the first bit depth is N, the number of the brightness intervals is N-1, and the value range of the second bit depth is [2, N]; N is an integer greater than or equal to 6.

6. The control method according to claim 4, It is characterized in that The preset plurality of brightness intervals include a first brightness interval, a second brightness interval, a third brightness interval, a fourth brightness interval, a fifth brightness interval, a sixth brightness interval and a seventh brightness interval; The first brightness range is [0,3], and the bit depth corresponding to the first brightness range is 2; The second brightness range is [4,7], and the bit depth corresponding to the second brightness range is 3; The third brightness range is [8, 15], and the bit depth corresponding to the third brightness range is 4; The fourth brightness range is [16, 31], and the bit depth corresponding to the fourth brightness range is 5; The fifth brightness range is [32, 63], and the bit depth corresponding to the fifth brightness range is 6; The sixth brightness range is [64, 127], and the bit depth corresponding to the sixth brightness range is 7; The seventh brightness range is [128, 255], and the bit depth corresponding to the seventh brightness range is 8.

7. The control method according to claim 1, It is characterized in that The original image signal includes N-bit first data corresponding to a plurality of sub-pixels; and converting the original image signal into an intermediate image signal according to the display brightness includes: For each of the sub-pixels, right-shift the N-bit first data by M bits to obtain N-bit second data, where N is the first bit depth, and M is the difference between the first bit depth and the second bit depth; Remove M high-order values ​​from the N-bit second data to obtain P-bit third data; The intermediate image signal is obtained based on P-bit third data corresponding to each of the plurality of sub-pixels; P is the second bit depth.

8. The control method according to claim 7, It is characterized in that The step of 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 the target image signal for display, comprises: The intermediate image signal is sent to the display driving circuit so that the display driving circuit performs: For each of the P-bit third data of the sub-pixel, a preset coding value is added to the end of the coding of the third data to obtain N-bit fourth data; The target image signal is obtained according to the N-bit fourth data respectively corresponding to the plurality of sub-pixels to output for display.

9. A display control device, It is characterized in that The control device comprises: An acquisition module, used to acquire the display brightness of the display module and the original image signal output to the display driving circuit of the display module; a conversion module, configured to convert the original image signal into an intermediate image signal according to the display brightness; a first bit depth of the original image signal being greater than or equal to a second bit depth of the intermediate image signal, and the display brightness being positively correlated with the second bit depth; A sending module is used 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 it for display; the third bit depth of the target image signal is the same as the first bit depth.

10. A display device, It is characterized in that The display device includes a processor, a converter and a display module; the converter is connected between the processor and the display module; The converter is used to: obtain the display brightness of the display module and the original image signal output by the processor; convert the original image signal into an intermediate image signal according to the display brightness; and send the intermediate image signal to the display module; 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 is used to: convert the intermediate image signal into a target image signal and output it for display; the third bit depth of the target image signal is the same as the first bit depth.

Images