WO2020200015A1 - 一种对比度提升算法及双面板显示装置 - Google Patents

一种对比度提升算法及双面板显示装置 Download PDF

Info

Publication number
WO2020200015A1
WO2020200015A1 PCT/CN2020/081251 CN2020081251W WO2020200015A1 WO 2020200015 A1 WO2020200015 A1 WO 2020200015A1 CN 2020081251 W CN2020081251 W CN 2020081251W WO 2020200015 A1 WO2020200015 A1 WO 2020200015A1
Authority
WO
WIPO (PCT)
Prior art keywords
brightness
pixel
local
value
modeling
Prior art date
Application number
PCT/CN2020/081251
Other languages
English (en)
French (fr)
Inventor
葛中峰
田广
Original Assignee
海信视像科技股份有限公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 海信视像科技股份有限公司 filed Critical 海信视像科技股份有限公司
Priority to US16/847,942 priority Critical patent/US11263987B2/en
Publication of WO2020200015A1 publication Critical patent/WO2020200015A1/zh

Links

Images

Classifications

    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
    • G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
    • G09G3/34—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source
    • G09G3/36—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source using liquid crystals
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
    • G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
    • G09G3/34—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
    • G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
    • G09G3/34—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source
    • G09G3/3406—Control of illumination source
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2320/00—Control of display operating conditions
    • G09G2320/06—Adjustment of display parameters
    • G09G2320/0626—Adjustment of display parameters for control of overall brightness

Definitions

  • the present disclosure relates to the field of display technology, and in particular to a contrast enhancement algorithm and a dual-panel display device.
  • Fig. 1 is a schematic structural diagram of a display device.
  • the display device includes a light-emitting source 1 and an LCD panel 2.
  • the light-emitting source 1 provides background light for the LCD panel 2 so that the LCD panel 2 can display images.
  • Figure 2 is a display screen, where the first partial area of the displayed image is a low-brightness screen, and the low-brightness background light is suitable for the second display image.
  • the local area is a high-brightness picture, which is suitable for high-brightness background light.
  • the purpose of the present disclosure is to provide a contrast enhancement algorithm and a double panel display device.
  • the first aspect of the present disclosure shows a contrast enhancement algorithm applied to a dual-panel display device, including: receiving the RGB value of each second pixel of a display image, and determining each first pixel according to the RGB value of each second pixel The brightness value of the pixel, wherein the second pixel is a pixel located on the second panel of the dual panel display device, and the first pixel is a pixel located on the first panel of the dual panel display device, The first panel is located between the light-emitting source and the second panel; according to the brightness value of each first pixel, statistics of the local area brightness value and the global image brightness value are performed to determine the local brightness adjustment factor and the global brightness adjustment factor Calculate the brightness driving signal corresponding to the first pixel according to the brightness value of each first pixel, the local brightness adjustment factor, and the global brightness adjustment factor, wherein the brightness driving signal is used to adjust the transparency of the corresponding pixel of the first panel The light rate, the global brightness adjustment factor is used to adjust the output brightness value of the pixel corresponding to the first panel.
  • the step of calculating the brightness driving signal corresponding to the first pixel point according to the brightness value of each first pixel point, the local brightness adjustment factor and the global brightness adjustment factor includes: calculating the first pixel point according to the local brightness adjustment factor.
  • the brightness value of a pixel is stretched and adjusted to generate a local brightness adjustment value
  • the brightness value of the first pixel is stretched and adjusted according to the global brightness adjustment factor to generate a global brightness adjustment value; according to the local brightness adjustment value and the global brightness Adjust the value to calculate the brightness drive signal corresponding to the first pixel.
  • the global brightness adjustment factor includes: a global brightness up-regulation factor and a global brightness down-regulation factor.
  • the brightness value of the first pixel is stretched and adjusted according to the global brightness adjustment factor to generate a global brightness adjustment value.
  • the steps include: calculating the average brightness of the displayed image according to the brightness value of each first pixel; for a first pixel among the plurality of first pixels, if the brightness value of the first pixel is less than that of the displayed image The brightness average value, according to the global brightness down-regulation factor, lower the brightness value of the first pixel to generate a global brightness adjustment value; if the brightness value of the first pixel is greater than the average brightness of the displayed image, according to the The global brightness up-regulation factor increases the brightness value of the first pixel to generate a global brightness adjustment value.
  • the local brightness adjustment factor includes: a local brightness up-regulation factor and a local brightness down-regulation factor.
  • the brightness value of the first pixel is stretched and adjusted according to the local brightness adjustment factor to generate a local brightness adjustment value.
  • the steps include: for any first pixel, m*n pixel blocks with the first pixel position as the center constitute a local area, and the brightness value of the local area includes: the brightness value of the m*n pixels;
  • the brightness value of the area calculate the average brightness of the local area; if the brightness value of the first pixel is less than the average brightness of the local area, then according to the local brightness down-regulation factor, the brightness value of the first pixel is reduced to generate the local brightness Adjustment value; if the brightness value of the first pixel is greater than the average brightness of the local area, according to the local brightness up-regulation factor, the brightness value of the first pixel is increased to generate a local brightness adjustment value.
  • the step of calculating the brightness driving signal corresponding to the first pixel point includes: calculating the local brightness weight coefficient according to the local area brightness value corresponding to the first pixel point Calculate the local brightness output value according to the local brightness adjustment value and the local brightness weight coefficient, and calculate the global brightness output value according to the global brightness adjustment value and the global brightness weight coefficient, wherein the local brightness weight coefficient and the The sum of the global brightness weight coefficients is 1. According to the local brightness output value and the global brightness output value, the brightness driving signal corresponding to the first pixel is calculated.
  • the calculation of the local brightness weight coefficient includes: selecting N local modeling regions, the local modeling regions including: the modeling brightness value of the first modeling pixel, and the first modeling The neighborhood pixel brightness value of the pixel point neighborhood, and the local modeling brightness weight coefficient corresponding to the first modeling pixel point; according to the modeling brightness value and the neighborhood pixel brightness value, the calculation of the first modeling pixel point Modeling brightness complexity; according to the modeling brightness complexity and local modeling brightness weight coefficients, construct a first local brightness weight coefficient curve; for any one of the plurality of first pixels, according to the corresponding first pixel Local area brightness value, calculating the complexity of the first pixel, and calculating the local brightness corresponding to the first modeled pixel based on the complexity of the first pixel and the first local brightness weight coefficient curve Weight coefficient.
  • the calculation of the local brightness weight coefficient includes: selecting N local modeling regions, the local modeling regions include: the brightness values of the local modeling regions, and the corresponding pixel points of the second modeling Local modeling brightness weight coefficient, the brightness value of the local modeling area includes: the modeling brightness value of the second modeling pixel point, and the neighborhood pixel brightness value of the second modeling pixel point neighborhood; statistical local construction Generate the first modeling frequency set for the modeling frequency of each brightness value in the mode area; traverse the first modeling frequency set, delete the first modeling frequency less than the preset frequency, and generate the second modeling frequency set; Second, the modeling quantity of the brightness value contained in the modeling frequency set, and construct the second local brightness weight coefficient curve according to the modeling quantity and the local modeling brightness weight coefficient; for any one of the first pixel points 1. Count the number of the brightness value of the local area corresponding to the first pixel with a frequency greater than the preset frequency, and calculate the local corresponding to the first pixel based on the number and the second local brightness weight coefficient curve Brightness weight coefficient.
  • the calculation of the local brightness weight coefficient includes: selecting N local modeling regions, the local modeling regions including: the modeling brightness value of the third modeling pixel, and the third modeling pixel The bordering brightness value of the third modeling pixel point bordered by the point, and the local modeling brightness weight coefficient corresponding to the third modeling pixel point; calculate the third modeling according to the modeling brightness value and the bordering brightness value The modeled brightness feature of the pixel; constructs a third local brightness weight coefficient curve according to the modeled brightness feature and the local modeled brightness weight coefficient; for a first pixel among the plurality of first pixels, calculate the first pixel According to the brightness feature of a pixel point, the local brightness weight coefficient corresponding to the first pixel point is calculated according to the brightness feature of the first pixel point and the third local brightness weight coefficient curve.
  • the method further includes: performing statistics on the RGB values of the local area according to the RGB values of the plurality of second pixels to determine the local color adjustment factor; and determining the local color adjustment factor according to the global RGB values of the second pixels of the second panel. Value, and the global image brightness value statistics of the second panel to determine the global color adjustment factor;
  • the color drive signal corresponding to the second pixel is calculated, and the color drive signal is used to adjust the second panel corresponding to the second pixel. RGB value.
  • a second aspect of the present disclosure provides a dual-panel display device.
  • the device includes a processor, a first panel, connected to the processor and configured to receive a brightness drive signal, and adjust the corresponding first pixel according to the brightness drive signal.
  • the light transmittance of the dot and the second panel are connected to the processor and configured to receive the color driving signal, and adjust the RGB value of the corresponding second pixel according to the color driving signal;
  • the processor is configured to execute: receiving The RGB value of each second pixel of the displayed image is determined according to the RGB value of each second pixel to determine the brightness value of each first pixel, where the second pixel is located in the double-panel display device
  • the pixels of the second panel, the first pixels are pixels located on the first panel of the dual-panel display device, and the first panel is located between the light-emitting source and the second panel; according to each first pixel Perform local area brightness value statistics and global image brightness value statistics to determine the local brightness adjustment factor and global brightness adjustment factor; according to the brightness value of each first pixel,
  • Figure 1 is a schematic diagram of the structure of a display device
  • Figure 2 is a schematic diagram of image brightness area division of a frame of display screen
  • FIG. 3 is a schematic structural diagram of a dual-panel display device provided by an embodiment of the disclosure.
  • FIG. 4 is a schematic diagram of the first panel of the dual panel display device provided by an embodiment of the disclosure showing different light-transmitting areas
  • FIG. 5 is a schematic diagram of an exploded structure of a dual-panel display device provided by an embodiment of the disclosure.
  • FIG. 6 is a schematic diagram of an exploded structure of a double panel display device provided by another embodiment of the present disclosure.
  • FIG. 7 is a functional block diagram of a dual-panel display device according to an embodiment of the disclosure.
  • FIG. 8 is a functional block diagram of a control system of a dual-panel display device according to an embodiment of the disclosure.
  • FIG. 9 is a block diagram of the principle of multi-channel backlight driving in multi-zone backlight control according to an embodiment of the disclosure.
  • FIG. 10 is a schematic diagram of a gain adjustment curve of a backlight value shown in an embodiment of the disclosure.
  • FIG. 11 is a detailed functional block diagram of the control system of the dual-panel display device according to an embodiment of the disclosure.
  • FIG. 12 is a schematic diagram of a contrast enhancement algorithm according to an embodiment of the disclosure.
  • Fig. 13 is a schematic diagram showing a 9*9 neighborhood according to an embodiment of the present disclosure.
  • FIG. 14 is a schematic diagram showing a brightness value adjustment curve according to an embodiment of the present disclosure.
  • FIG. 15 is a flowchart of a brightness driving method according to an embodiment of the present disclosure.
  • FIG. 17 is a schematic diagram of a brightness compensation factor model according to an embodiment of the present disclosure.
  • FIG. 18 is a schematic diagram showing entries according to an embodiment of the present disclosure.
  • FIG. 19 is a flowchart showing a brightness driving method according to another embodiment of the present disclosure.
  • Fig. 20 is a schematic diagram showing an area of a display image according to an embodiment of the present disclosure.
  • connection should be understood in a broad sense, for example, it can be a contact connection or a detachable connection. Connected or integrally connected; for those of ordinary skill in the art, the specific meaning of the above terms in the present disclosure can be understood in specific situations.
  • VBO Vertex Buffer Objects, vertex buffer object
  • the vertex buffer object VBO is a memory buffer area opened in the storage space of the graphics card, used to store various attribute information of vertices, such as vertex coordinates, vertices Normal vector, vertex color data, etc.
  • RAM Random Access Memory
  • main memory also called main memory
  • main memory is an internal memory that directly exchanges data with the CPU. It can read and write at any time, and it is very fast, and is usually used as a temporary data storage medium for operating systems or other running programs.
  • SPI Serial Peripheral Interface, serial peripheral interface
  • FIG. 3 which includes: a light-emitting source 1, a first panel 3, and a second panel 4.
  • the first panel 3 is located between the light emitting source 1 and the second panel 4.
  • the second panel 4 is used for RGB detail processing and image compensation
  • the first panel 3 is used for contrast enhancement through the transmittance of pixels in different regions.
  • the light transmittance of each light-transmitting area of the first panel 3 can be adjusted. Therefore, the light emitted by the light-emitting source 1 passes through different areas of the first panel 3 and presents different brightness, so that a display screen has different background light intensity in different areas. Effect.
  • Fig. 4 is a schematic diagram of the first panel presenting different light-transmitting areas, where the first light-transmitting area and the second light-transmitting area of the first panel 3 correspond to dark scene parts and bright scene parts in the image.
  • the light transmittance of the first light-transmitting area is 20%
  • the light transmittance of the second light-transmitting area is 80%.
  • the light emitted by the light source 1 passes through the first panel 3 to provide the LCD panel 2 with background light.
  • the background of the LCD panel 2 and the area corresponding to the first light-transmitting area is dark, and the background of the LCD panel 2 and the second light-transmitting area is bright.
  • the dual-panel display device includes a backlight module 100, a first panel 200, a second panel 300, and an adhesive layer 400 stacked in sequence.
  • 5 and 6 are schematic diagrams of the structure of a dual panel display device according to an embodiment of the present disclosure
  • FIG. 7 is a principle block diagram of a dual panel display device according to an embodiment of the present disclosure.
  • the backlight module 100 is used to provide a light source to emit light
  • the first panel 200 is a light control panel for controlling the luminous flux of the light from the backlight module 100 into the second panel 300
  • the second The panel 300 is a color panel for displaying images
  • the adhesive layer 400 is used for bonding and fixing the first panel 200 and the second panel 300 into a whole to form an integrated panel.
  • the first panel 200 sequentially includes a first polarizer 201 adjacent to the backlight module 100, a first liquid crystal light valve layer 202, and a second polarizer 203, the first polarizer 201 and the second polarizer 203.
  • the transmission axes of the two polarizers 203 are perpendicular to each other.
  • the light from the backlight module 100 passes through the first polarizer 201 and then becomes the first polarized light.
  • the first polarized light enters the first liquid crystal light valve layer 202.
  • the rotation of the liquid crystal in the first liquid crystal light valve layer 202 is controlled by the voltage, so that the direction of the first polarized light is rotated accordingly, and the first polarized light after the angle rotation enters the second polarizer 203 and becomes the second polarized light. . Since the transmission axes of the first polarizer 201 and the second polarizer 203 are perpendicular to each other, the control of the light flux entering the second panel 300 is thus achieved. It should be noted that the first panel 200 does not include a filter. If the light from the backlight module 100 is white light, the first panel 200 is a monochromatic panel.
  • the second panel 300 sequentially includes a third polarizer 301 adjacent to the first panel 200, a second liquid crystal light valve layer 302, a filter 303, and a fourth polarizer 304.
  • the third The transmission axes of the polarizer 301 and the fourth polarizer 304 are perpendicular to each other.
  • the transmission axes of the second polarizer 203 and the third polarizer 301 are parallel to each other.
  • the rotation of the liquid crystal in the liquid crystal light valve layer 302 causes the polarization direction of the second polarized light to rotate accordingly. After the angle rotation, the second polarized light enters the filter 303 and becomes colored light, and then the colored light enters the second polarized light.
  • the four polarizer 304 becomes the third polarized light, because the transmission axes of the third polarizer 301 and the fourth polarizer 304 are perpendicular to each other, thereby realizing the control of the luminous flux of the colored light and realizing the color display of the image.
  • the adhesive layer 400 uses the surface bonding method to bond the first panel 200 and the second panel 300 are glued and fixed together, and the surface bonding is full bonding, that is, an adhesive layer is laid on the entire surface.
  • the adhesive layer 400 adopts a transparent glue layer, for example, OCA (Optically Clear Adhesive) optical glue or silica gel OCR (Optical Clear Resin).
  • OCA Optically Clear Adhesive
  • silica gel OCR Optical Clear Resin
  • the thickness of the bonding layer is between 0.15-0.75 mm, preferably 0.25-0.5 mm.
  • the first panel 200 may include a polarizer, such as the second polarizer 203
  • the second panel 300 may include a polarizer, such as the third polarizer 301
  • the first panel 200 and The second panel 300 has two polarizers respectively.
  • the first panel 200 and the second panel 300 share a polarizer.
  • FIG. 6 shows a situation where the two share a polarizer. Because the default is one polarizer, it can meet the display requirements. In this case, the cost of the display device can be reduced. As shown in FIG. 6, the difference from FIG. 5 is that the double-panel display device does not include the third polarizer 301.
  • the light transmission axis of the first polarizer 201 and the light transmission axis of the second polarizer 203 are perpendicular to each other, and the light transmission axis of the second polarizer 203 and the light transmission axis of the fourth polarizer 304 are perpendicular to each other.
  • the second polarized light from the first panel 200 directly enters the second liquid crystal light valve layer 302, and the second liquid crystal light valve layer is controlled by voltage according to the content of the displayed image
  • the rotation of the liquid crystal in 302 causes the direction of the second polarized light to rotate accordingly.
  • the second polarized light after the angle rotation enters the filter 303 and becomes colored light, and then the colored light enters the fourth polarizer 304. It is the third polarized light, because the transmission axes of the second polarizer 203 and the fourth polarizer 304 are perpendicular to each other, thereby realizing the control of the luminous flux of the colored light and realizing the color display of the image.
  • the adhesive layer 400 is located between the second polarizer 203 and the second liquid crystal light valve layer 302. The position of the adhesive layer 400 is not limited to this, and the adhesive layer 400 may also be located between the first liquid crystal light valve layer 202 and the second polarizer 203.
  • the structure of the first liquid crystal light valve layer 202 and the second liquid crystal light valve layer 302 is similar, including an upper substrate, a lower substrate, and a liquid crystal cell located between the upper substrate and the lower substrate.
  • the liquid crystal light valve layers in the first panel 200 and the second panel 300 both include a plurality of liquid crystal cells, similar to the principle of light control in the second panel 300 (color panel), the first panel 200 can realize a single pixel as an independent light valve , To achieve pixel-level light control. Compared with a display device with only one panel, a dual-panel display device has two levels of pixel-level light control, achieving more precise control. Since the first panel 200 realizes pixel-level light control, compared with a single-panel display device, the cooperation of the first panel 200 and the second panel 300 can greatly reduce the brightness of the black screen to solve the problem of the single-panel display device.
  • the liquid crystal light valve layer cannot be absolutely opaque, and the black screen has a certain brightness problem, which significantly improves the static contrast of the liquid crystal display device.
  • the first panel 200 uses the rotation of the polarizer and the liquid crystal to achieve light control, and the transmittance of the polarizer is 38%-48%, this will reduce the overall light transmittance of the display device. Therefore, in the present disclosure, by making the resolution of the first panel 200 smaller than the resolution of the second panel 300, that is, the number of pixels in the first panel 200 is less than the number of pixels in the second panel 300, avoiding the use of double layers
  • the panel causes the light transmittance of the light from the backlight module to pass through the first panel to decrease, resulting in insufficient display brightness of the display device.
  • the ratio of the number of pixels in the second panel 300 to the number of pixels in the first panel 200 is not less than 4:1, for example: 4:1, 16:1, that is, when the resolution of the second panel 300 is 8K,
  • the resolution of the first panel 200 may be 4K or 2K.
  • the resolution of the first panel 200 may be 2K.
  • the resolution of the first panel 200 is 1920*1080
  • the resolution of the second panel 300 is 3840*2160.
  • the backlight module 100 adopts a multiple backlight zone control method, that is, the backlight source in the backlight module 100 is divided into a plurality of backlight zones 101 according to the display
  • the brightness information contained in the image information dynamically changes the brightness of each backlight zone 101.
  • the bright part of the image corresponds to a higher backlight brightness
  • the dark scene part of the image corresponds to a lower backlight brightness.
  • the constant backlight by dynamically adjusting the brightness of the backlight, can solve the problem of weak light leakage and high power consumption in the pure black field, further improve the contrast of light and dark of the picture, and improve the picture quality.
  • the combination of the double-layer panel and the backlight zone control further solves the problem that the dark field picture is not black enough, and better improves the display contrast of the picture.
  • Fig. 8 is a functional block diagram of the control system in a double panel display device.
  • the double panel display device includes a main chip SOC (System on Chip), a double panel processor, a first panel, and a first panel timing controller ( Timing Controller, TCON), second panel, second panel timing controller, backlight control microprocessor (Microcontroller Unit, MCU), backlight driver, backlight.
  • SOC System on Chip
  • TCON Timing Controller
  • MCU backlight control microprocessor
  • backlight driver backlight.
  • the main chip SOC outputs an image signal
  • the dual-panel processor receives the image signal.
  • the dual-panel processor is configured to generate dimming data for the first panel in response to the image signal, and the dimming data is sent to the first panel timing controller ,
  • the first panel timing controller drives and controls the first panel according to the dimming data;
  • the dual-panel processor is also configured to generate image data for the second panel in response to the image signal, and the image data is sent to the second panel for timing control
  • the second panel timing controller controls and displays the second panel according to the image data;
  • the dual-panel processor is also configured to generate backlight data for backlight control in response to the above image signal, the backlight data is sent to the backlight control MCU, and the backlight control
  • the MCU generates dimming information such as duty cycle and current and sends it to the backlight driver, and the backlight driver implements driving control of the backlight according to the dimming information such as duty cycle and current.
  • the resolution of the first panel is 1920*1080 (2K) and the resolution of the second panel is 3840*2160 (4K) as an example.
  • the process of generating dimming data receives the 4K image data signal from the main chip SOC.
  • the processor first converts the RGB value of the pixel in the image to the first brightness value (Y) of the pixel, and then down Y Sampling processing to generate the second brightness value corresponding to the pixels of the first panel, that is, to achieve 4K to 2K resolution reduction processing, and then perform Y contrast enhancement according to the second brightness value, where Y contrast enhancement includes the local area and the entire area
  • the improvement of brightness is specifically based on the second brightness value, the local area brightness value statistics and the global image brightness value statistics, the determination of the local brightness adjustment factor and the global brightness adjustment factor, and the second brightness value, the local brightness adjustment factor and the global brightness adjustment Factor Y contrast enhancement; then according to the different contrast of the picture, the medium and high brightness parts are enhanced to increase the overall brightness of the medium and high brightness parts; then the medium and high brightness parts are subjected to edge blur processing, and the edge blur processing makes the different brightness areas within the frame smooth transition.
  • spatial filtering is used to smooth the brightness to solve the uneven light wave waveform caused by the discrete liquid crystal cells in the first panel and the spacer between the liquid crystal cells.
  • the finally generated dimming data is transmitted to the timing controller (TCON) of the first panel through the LVDS (Low Voltage Differential Signaling) interface, and the first panel timing controller drives and controls the first panel according to the dimming data.
  • TCON timing controller
  • LVDS Low Voltage Differential Signaling
  • Image data generation process After the dual-panel processor receives the 4K image data signal from the main chip SOC, the processor will improve the RGB contrast of the pixel, and multiplex the global image brightness statistics used to generate the dimming data.
  • the image RGB value and the local area RGB value are processed for overall and local RGB contrast enhancement processing to make the black part darker and the bright part brighter to improve the overall contrast of the picture; and in order to better maintain the middle when the brightness of the first panel decreases
  • the brightness of the low-bright part is compensated for the image accordingly, so that the brightness of the display screen lost through the first panel is compensated on the second panel.
  • the finally generated image data is transmitted to the timing controller (TCON) of the second panel through the VBO (V-By-One) interface, and the second panel timing controller drives and controls the second panel according to the dimming data.
  • the multi-zone control technology and the dual-panel technology are used in combination. If the traditional backlight control is directly combined with the dual-panel platform, the two modules are completely independent, and the backlight control does not take into account the dual
  • the particularity of the panel platform the first panel will reduce the transmittance of the backlight
  • the backlight control is easy to darken, and the more backlight partitions, the more serious the problem. Therefore, the process of generating backlight data in the present disclosure is as follows:
  • a first-level down-sampling module is added.
  • the down-sampling module implements the direct down-sampling of the original 1920x1080 to the target backlight partition number, and then performs temporal filtering, that is, the backlight value of the current frame and the backlight of the previous frame
  • temporal filtering that is, the backlight value of the current frame and the backlight of the previous frame
  • the value is mixed (blending) to obtain the mixed data, and then written into the RAM, the above mixed data can be read from the RAM, and finally the backlight data is obtained.
  • the obtained backlight data is transmitted to the backlight control MCU through the SPI interface, and the backlight control
  • the MCU generates dimming information such as duty cycle and current and sends it to the backlight driver, and the backlight driver implements driving control of the backlight according to the dimming information such as duty cycle and current.
  • the combined use of multi-zone backlight control and double-panel technology is realized, and the local backlights are as bright as possible by multiplexing data, ensuring that the double-panel display device as a whole transmits more brightness and saving hardware resources.
  • FIG 9 is a block diagram of the multi-channel backlight driving principle in the multi-zone backlight control.
  • the backlight control MCU processes the brightness information of each backlight zone, searches for the mapping table pre-stored in the zone mapping unit, and at the same time according to the actual zone coordinates found Position adjustment of the duty cycle of each backlight zone.
  • the adjustment method of the partition duty cycle includes the backlight control MCU sending the backlight duty cycle data of each backlight partition to the backlight driver, specifically a PWM (Pulse-Width Modulation) driver, which is driven by the PWM driver to generate a corresponding PWM control signal Backlight (LED string).
  • PWM Pulse-Width Modulation
  • the backlight processing unit may send current data to the PWM driver, and the PWM driver adjusts the current according to the current data and the preset reference voltage Vref.
  • the PWM driver is formed by cascading multiple chips, and each chip can drive multiple PWM output currents to the LED light string.
  • the LED backlight peak enhancement technology is used to dynamically increase the backlight peak brightness of bright scenes and conventional display pictures to highlight the bright parts of the picture, and achieve the effect of further improving picture contrast and picture layering.
  • FIG. 10 it is a schematic diagram of the gain adjustment area of the backlight value in the embodiment of the disclosure, where the abscissa is the backlight value and the value range is [0,255], the ordinate is the gain value, and the value range is [1 , Positive infinity), however, in the actual execution process, the value range of the gain value can be set to [1,2] according to the requirements of the actual power setting; and the gain value is not limited to integers, and can also be non- Integer.
  • the gain adjustment curve can be divided into a low-brightness enhancement interval, a high-brightness enhancement interval, and a power control interval.
  • the gain value is in the low-brightness enhancement interval; as the display content in the backlight area changes, when the average value of the backlight value in the backlight area falls within the high-brightness enhancement interval, the gain value In the highlight enhancement interval, the highlight part of the picture can be better highlighted; when the average value of the backlight value in the backlight area is high, because the brightness of the entire picture in the backlight area is high enough, there is basically no need to enhance the backlight, but because Power consumption needs to reduce the backlight gain effect. Because the determined average value of the backlight value of each backlight area is not the same, the determined gain value is also not the same, so that the picture has a large contrast and a sense of layering during the display process.
  • an embodiment of the present application shows a dual-panel display device.
  • the device includes:
  • a processor a first panel connected to the processor, and a second panel connected to the processor;
  • the processor receives the RGB value of the second pixel uploaded by the VBO, converts the RGB value of the second pixel to the brightness value (Y) of the second pixel, and then down-samples Y to generate the brightness of the first pixel value.
  • the brightness value of the first pixel perform local area brightness value statistics, determine the local brightness adjustment factor and the local brightness weight coefficient; perform local contrast on the brightness value of the first pixel according to the local brightness adjustment factor and the local brightness weight coefficient Stretching to generate local brightness output values;
  • global image brightness value statistics are performed according to the brightness value of the first pixel to determine the global brightness adjustment factor and global brightness weight coefficient; according to the global brightness adjustment factor and the global brightness weight coefficient pair
  • the brightness value of the first pixel is stretched for the global contrast to generate a global brightness output value.
  • the global brightness output value and the local brightness output value are mixed to generate a brightness drive signal; the brightness drive signal is sent to the first panel in the form of an LVDS signal.
  • the processor receives the RGB value of the second pixel uploaded by the VBO, performs statistics on the RGB value of the local area according to the RGB value of the second pixel, and determines the local color adjustment factor and the local color weight coefficient.
  • the local color adjustment factor and the local color weight coefficient are used to stretch the local contrast of the RGB value of the second pixel to generate a local color output value; the global statistical result of the brightness value of the first pixel and the second
  • the statistical result of the global RGB value of the pixel is also used to stretch the global contrast of the RGB value of the second pixel to generate a global color output value.
  • the global color output value and the local color output value are then mixed to generate a color drive signal, which is sent to the first panel in the form of a VBO signal.
  • the brightness driving signal transmitted in the form of an LVDS signal is down-sampled, filtered, and then sent to the backlight through the SPI serial external interface to adjust the brightness of the background light provided by the light-emitting source.
  • the processor is configured to execute the following steps S1-S3: as shown in FIG. 12.
  • Step S1 receiving the RGB value of each second pixel of the display image, and determining the brightness value of each first pixel according to the RGB value of each second pixel, wherein the second pixel is located in the double
  • the pixels of the second panel of the panel display device, the first pixel points are the pixels of the first panel of the double panel display device, and the first panel is located between the light-emitting source and the second panel.
  • Step S11 the RGB value of the second pixel is converted into the brightness value of the second pixel
  • the most used RGB color space in computers corresponds to the three colors of red, green, and blue; various colors are formed by adjusting the ratio of the three color components. Generally, 1, 2, 4, 8, 16, 24, and 32 bits can be used to store these three colors. In the embodiment of the present application, the RGB component is represented by 8 bits, and the maximum value is 255.
  • RGB value to Y value (brightness value) conversion formula is:
  • the RGB value is (0,0,255), which is obtained by the above formula
  • the Y value of is 29, so the transmitted light brightness value will be much reduced compared to the RGB value (0,0,255) under the pure blue field.
  • the maximum value of R, G, and B is selected as the Y value.
  • the transmitted light brightness value will increase a lot compared to the Y value calculated by the conversion formula of the pure blue field (0,0,255).
  • the RGB value is only converted to the Y value, it is reasonable to use the maximum value of the RGB value at this time.
  • the calculation formula of the brightness value Y is as follows:
  • Step S12 down-sample the brightness value of the second pixel to the brightness value of the first pixel.
  • the RGB value of each second pixel of the display image is converted into the brightness value of the second pixel by the above method, and then the brightness value of the second pixel is down-sampled to generate the corresponding brightness value of the first pixel.
  • the embodiment of the present application controls the second panel with 4K pixels, and the second panel has 3840*2160 second pixels.
  • the first panel has 1920*1080 first pixels.
  • the 4K pixels are down-sampled to obtain 2K pixels, and 1920*1080 small areas are generated.
  • the first pixel points correspond to the second panel small areas one-to-one; the brightness value of each first pixel point is Calculation method: 4K brightness values are scaled using the principle of scaling every four values to one value; the same as general scaling; using the maximum brightness of four pixels; using the average brightness of four pixels; using four The minimum brightness of a pixel; the median brightness of four pixels is used to finally generate a set of 1920*1080 first pixel brightness values.
  • Step S2 Perform local area brightness value statistics and global image brightness value statistics according to the brightness value of each first pixel, and determine the local brightness adjustment factor and the global brightness adjustment factor;
  • the global brightness adjustment factor includes: a global brightness down-regulation factor global_min_y and a global brightness up-regulation factor global_max_y;
  • the maximum brightness P_frame_max, the minimum brightness P_frame_min, and the average brightness P_frame_avg of the image can be directly obtained by traversing the brightness value set of the first pixel; the maximum brightness and the minimum brightness are not actual values, but according to Statistics.
  • the grayscale value is P_frame_max.
  • the number of pixels with the minimum grayscale value is preset to 8, when the number of pixels with a 0-level grayscale is only one, the number of pixels with a first-level grayscale value is 4, and the number of pixels with a second-level grayscale When there are more than 3, the minimum brightness P_frame_min is set to 2 gray scale values. In order to avoid interference and jump.
  • global_min_y f(P_frame_min)
  • global_min_y refers to the P_frame_min function
  • global_max_y f(P_frame_max)
  • global_max_y refers to the P_frame_max function
  • the hardware implementation method can adopt the Lookuptable method.
  • the global brightness adjustment factor can be calculated by using the black scene judgment of the screen background, where the black scene judgment of the screen background:
  • sum_gray_cont After the histogram statistics of the image, it is found that the black scene image of the screen background, the number of pixels distributed between the brightness value Gray_TH0 to Gray_TH1, sta-gray[k] is more and greater than NUM_TH0 (Pre-set value), and the number of brightness values between Gray_TH0 and Gray_TH1 is small, generally not more than the threshold number TH0; according to the brightness value distribution, sta-gray[k] between Gray_TH0 and Gray_TH1 is counted, and the statistics satisfy sta- Gray[k] is the number cont greater than or equal to NUM_TH0; and the cumulative sum_gray_cont of sta-gray[k] under the condition that cont is less than or equal to TH0 is calculated.
  • NUM_TH0 Pre-set value
  • the statistical brightness value is 12, the brightness value is 13, the brightness value is 14, the brightness value is 15, the brightness value is 16, the brightness value is 17, the statistical brightness value is 18, the brightness value is 19, and the brightness value is 20 corresponding to the pixel.
  • the number of sta-gray[k]; statistics show that the brightness value of sta-gray[k] is greater than or equal to 3000: the brightness value is 13, the brightness value is 14, then sum_gray_cont sta-gray[13]+sta-gray[ 14].
  • sum_gray_cont is greater than or equal to sum_TH (pre-set value).
  • global_min_y1>global_min_y2, f1 and f2 are function curves.
  • the local brightness adjustment factor includes: a local brightness down-regulation factor local_min_y and a local brightness up-regulation factor local_max_y;
  • an m*n pixel block is selected with the first pixel point position as the center, and the brightness values of the m*n pixel blocks constitute a local area brightness value set.
  • Each first pixel corresponds to a coordinate value (i, j), and the position of the first pixel is the center of m*n pixel blocks; as shown in Figure 13, the m*n pixel blocks can be 9* 9 blocks, the brightness values of the m*n pixel blocks constitute a local area brightness value set.
  • the usual method is to look up all the location point data, find the minimum brightness and maximum brightness of the local area, and add up the sum of the brightness values of all the first pixels in the local area and divide by the first pixel of the local area. The total number of one pixel gets the average brightness of the local area.
  • Step S3 Calculate the brightness driving signal corresponding to the first pixel according to the brightness value, local brightness adjustment factor and global brightness adjustment factor of each first pixel, wherein the brightness driving signal is used to adjust the corresponding pixel of the first panel
  • the light transmittance, the global brightness adjustment factor is used to adjust the output brightness value of the corresponding pixel of the first panel.
  • Step S31 calculation of the global brightness adjustment value:
  • P_out_global(i,j) (P_frame_avg–(P_frame_min-global_min_y))/(P_frame_avg-P_frame_min )*(P(i,j)-P_frame_avg)+P_frame_avg(3)
  • P_out_global(i,j) is the global brightness adjustment value
  • global_min_y is the global brightness reduction factor
  • P_out_global(i,j) (P_frame_avg–(P_frame_max+global_max_y))/(P_frame_avg-P_frame_max)*(P(i,j)-P_frame_avg)+P_frame_avg (5)
  • global_max_y is the global brightness up-regulation factor.
  • Step S32 calculation of local brightness adjustment value
  • P_out_local(i,j) (P_local_avg(i,j)–(P_local_min(i,j)-local_min_y(i,j)))/(P_local_avg(i,j)–P_local_min(i,j))*(P (i,j)-P_local_avg(i,j))+local_avg(i,j) (6)
  • P_out_local(i,j) is the second brightness adjustment value
  • local_min_y(i,j) is the regional brightness down-regulation factor
  • P_out_local(i,j) P_local_avg(i,j).
  • P_out_local(i,j) (P_local_avg(i,j)–(P_local_max(i,j)+local_max_y(i,j)))/(P_local_avg(i,j)-P_local_max(i,j))*(P (i,j)-P_local_avg(i,j))+P_local_avg(i,j).(8)
  • Step S33 calculation of the brightness driving signal
  • P_out(i,j) weight_local(i,j)*P_out_local(i,j)+weight_global*P_out_global(i,j);
  • weight_org(i,j) is the adjustment coefficient
  • P_out(i,j) is the luminance drive signal
  • weight_local(i,j) is the local luminance weight coefficient
  • weight_global is the global luminance weight coefficient
  • Step S331 the calculation process of the local brightness weight coefficient is as follows:
  • N local modeling regions are selected on the first panel, and the local modeling regions include: the modeling brightness value i of the first modeling pixel, and the first modeling pixel The domain brightness value of the point neighborhood (m*n-1) and the local modeling brightness weight coefficient weight_local(i,j) corresponding to the first modeling pixel are modeled .
  • the local modeling area also includes the modeling brightness complexity, including: the frequency of the brightness value i in the local modeling area hg(i) modeling the average value A modeling , and the frequency of the brightness value i appearing hg(i) modeling Power modeling of the energy value of, and Entropy modeling of the frequency hg(i) modeling of the brightness value i;
  • This calculation procedure is: the use of local modeling area luminance histogram statistics value frequency hg (i) i occurs modeling;
  • Entropy modeling — ⁇ i g h (i) modeling lgh g (i) modeling
  • Construct weight_local(i,j) modeling f (A modeling , Power modeling , Entropy modeling ) curve, that is, the first local brightness weight coefficient curve;
  • any first pixel point calculate the average value A(i,j) of the frequency h g (i) of the corresponding local area brightness value i of the first pixel point ,
  • the energy value Power(i,j), and the entropy value Entropy(i,j) substitute the A(i,j), Power(i,j), Entropy(i,j) into weight_local(i,j) )
  • Modeling f (A modeling , Power modeling , Entropy modeling ) curve, and the local brightness weight coefficient weight_local(i,j) corresponding to the first pixel is calculated.
  • N local modeling regions are selected on the first panel, and the local modeling regions include: the brightness value of the local modeling region, and the local modeling corresponding to the second modeling pixel.
  • a weight coefficient of the model brightness, the brightness value of the local modeling area includes: the model brightness value of the second modeled pixel, and the neighborhood brightness value of the neighborhood of the second modeled pixel;
  • any first pixel For any first pixel, count the number of local area brightness values corresponding to the first pixel with a frequency greater than a preset frequency, and calculate the first pixel based on the number and the second local brightness weight coefficient curve.
  • the local brightness weight coefficient corresponding to the pixel For any first pixel, count the number of local area brightness values corresponding to the first pixel with a frequency greater than a preset frequency, and calculate the first pixel based on the number and the second local brightness weight coefficient curve.
  • the local brightness weight coefficient corresponding to the pixel For any first pixel, count the number of local area brightness values corresponding to the first pixel with a frequency greater than a preset frequency
  • NUM_th0 is the preset frequency
  • the general NUM_th0 is 3000, this value can be configured (1920x1080 first panel resolution for example); take the first panel resolution 1920x1080 As an example, the range of count is 0-1920x1080; you can set count as the independent variable of the abscissa, weight_local(i,j) as the dependent variable of the ordinate, and the value range of the local brightness weight coefficient weight_local(i,j) is [0,1].
  • the embodiment of the present application shows another calculation method of the local brightness weight coefficient weight_local(i,j).
  • the N selected local modeling area on the first panel a local modeling area for any one of a first pixel (i.e., the third modeling pixels) of the luminance values p (i, j) modeling, Determine the brightness values of the two first pixels bordering the first pixel: the brightness value p(i ⁇ 1,j) of the first pixel on the first pixel is modeled , and the brightness value p of the first pixel on the second pixel is p (i,j ⁇ 1) modeling ;
  • p_diff0(i,j) modeling and p_diff1(i,j) modeling are the difference between the brightness value of the first pixel and the brightness value of the first pixel on the second and the brightness value of the first pixel on the first Value; through the above formula, the modeling brightness feature p_sum_diff(i,j) modeling or p_avg_diff(i,j) modeling can be obtained .
  • m*n is the number of pixels included in the local area brightness value set;
  • the center point is in the upper rows, left columns, lower rows, and right columns of the image; the data taken by the template exceeds the range of the image; used in the template Copy method;
  • the center point is (0,0) as an example; the upper left corner is filled with data of (0,0) points; the data in the upper right corner and the lower left column are respectively copied to the first row of the template
  • the data in the first column and the data in the first column; the data in the lower right corner is directly the data in the original image;
  • the format of data filling can also be symmetrical replication, taking the column as an example, the template includes -4, -3, -2, -1, 1, 2, 3, 4 columns; -4 column copy is not 1 column data but 4 column data, -3 column data copy 3 column data, -2 column data copy 2 column data, -1 column Copy the data of 1 column; the upper right corner still copies the data of (0,0).
  • the processor is further configured to:
  • each second pixel perform local area RGB value statistics to determine the local color adjustment factor; determine the global color adjustment factor according to the global RGB value of the second panel and the global image brightness value statistics of the second panel;
  • the color drive signal corresponding to the second pixel is calculated, and the color drive signal is used to adjust the second panel corresponding to the second pixel. RGB value.
  • the first panel is configured to receive a brightness driving signal, and adjust the light transmittance of the corresponding first pixel according to the brightness driving signal;
  • the second panel is used to receive a color drive signal, and adjust the RGB value corresponding to the second pixel according to the color drive signal.
  • the embodiments of the present application show a contrast enhancement algorithm and a dual-panel display device.
  • the present disclosure is used in an ultra-high-definition television image quality processing chip or Tcon chip, and can also be used in an FPGA or a multi-core processor. , Complete the control of the brightness of the double panel, realize the background light control effect of multiple local areas, and realize more precise background light "zone control". Under the condition of constant light source, the light transmittance of the first panel can be controlled to achieve fine The background light control can realize more precise zone control and further improve the dynamic contrast of the picture.
  • An embodiment of the present application shows a brightness driving method. The method includes the following steps S401-S404:
  • Step S401 Determine a brightness value set of a display image, where the brightness value set includes the brightness of each pixel of the display image;
  • the most used RGB color space in computers corresponds to the three colors of red, green, and blue; various colors are formed by adjusting the ratio of the three color components. Generally, 1, 2, 4, 8, 16, 24, and 32 bits can be used to store these three colors. In the embodiment of the present application, the RGB component is represented by 8 bits, and the maximum value is 255.
  • the RGB value of each pixel is first obtained, and then the RGB value is converted into a brightness value.
  • the maximum value of R, G, and B is selected as Y.
  • the Y value obtained by the above formula is 29, so that the transmitted light brightness value will be much reduced compared to the RGB value (0,0,255) in the pure blue field
  • the RGB value is only converted to the Y value, it is reasonable to use the maximum value of the RGB value at this time.
  • Each pixel corresponds to the brightness of a pixel, and the brightness of a displayed image is expressed as a set of pixel brightness ⁇ Y1, Y2, Y3... ⁇ .
  • Step S402 Determine the average value Lavg1 and the maximum value Lmax1 of the brightness in the display image according to the brightness value set;
  • the maximum value of brightness in the displayed image Lmax1 is calculated. This maximum value is not the largest of all brightness values, but the maximum value in a statistical sense. It is generally from 255 gray scale to 0 gray scale after the statistics are over. Find the level where the number of pixels is not zero and the number of pixels contained in each gray level needs to exceed a certain threshold (for example, 0.1% of the total number).
  • the number of pixels of the gray level is added to the number of pixels of the next level, until the number of pixels of the level that meets the conditions is found to stop; this gray level is the maximum brightness in the displayed image;
  • the average value of brightness Lavg1 if all the brightness values of the pixels of a displayed image are accumulated and then divided by the number of pixels, the accumulated data bit width will generally overflow, especially when the data bit width is 10bit and In the case of 12bit, in order to facilitate calculations, you can first calculate the average brightness of each row, and then calculate the average brightness of n rows, and then average the brightness averages of n rows to get the average brightness of the entire display image .
  • the display device usually uses the light mixing principle to display the displayed image, so each pixel can be divided into three sub-pixels of R ⁇ G ⁇ B.
  • the brightness of the three sub-pixels is different, and the brightness of each corresponding pixel is different.
  • the brightness of each pixel is the maximum value of the original brightness of the three sub-pixels in the pixel.
  • the sub-pixel with the maximum brightness in one pixel is used for statistics.
  • the statistics and calculations are smaller, which makes statistics and calculations easier and faster; on the other hand, This selects the pixel brightness corresponding to the sub-pixel with the largest original brightness among the three sub-pixels of R/G/B as a statistical quantity. Compared with the pixel brightness corresponding to the lowest or intermediate value of the original brightness in the three sub-pixels, the input is retained to the maximum. The original display image information of the display image, so that the information loss of the input display image is small, and the display image display effect is good.
  • Step S403 calculating a brightness compensation factor according to the average value and the maximum value of the brightness in the display image
  • the average value and maximum value of the brightness in the display image are substituted into the brightness compensation factor model to obtain the brightness compensation factor.
  • a brightness compensation factor model is constructed in advance, and the brightness compensation factor model is constructed based on the maximum value Lmax2 of the brightness in the modeled image and the average value Lavg2 of the brightness in the modeled image.
  • the construction process of the brightness compensation factor model is steps S4031-S4035:
  • Step S4031 selecting n groups of modeling images, each of which has the same Lmax2, and the Lmax2 is the maximum value of the brightness in the modeling image;
  • n groups of modeling images where the brightness value range of the modeling image is 0-255; the range of the maximum brightness of the corresponding modeling image is 0-255, and the range of the average brightness in the modeling image Is 0-255.
  • the maximum brightness of the selected n sets of modeling images is uniformly distributed in the interval of 0-255; specifically, if 11 sets of modeling images are selected, the maximum brightness Lmax2 in each set of modeling images is: 1, 25, 51, 76, 102, 127, 153, 178, 204, 229, 255.
  • Step S4032 For any set of modeling images, respectively calculate Lavg2 of each modeling image to generate a Lavg2 set, where Lavg2 is the average value of the brightness in the modeling image;
  • step S4035 the n relationship curves are constructed as a brightness compensation factor model.
  • the embodiment of the present application determines the contrast of the display screen, the contrast is generated based on the pixel brightness value of the display screen, and the brightness compensation factor of the entire display screen is determined according to the contrast.
  • scenes with high contrast require further Increase the contrast, so you can properly push down the low gray levels of the display screen, and properly raise the high gray levels, and try to maintain the original characteristics for scenes with low contrast.
  • the embodiment of the present application provides a calculation method for calculating the average brightness of each modeled image in each group. Specifically, the brightness value of each pixel of the modeled image is counted to generate a first brightness value set; the first brightness value set is traversed, the brightness values less than the preset brightness value are deleted, and the second brightness value set is generated; The average brightness value of the brightness value set is the average value of the brightness in the modeled image.
  • the preset brightness value is 10
  • pixels with brightness values less than 10 are deleted during the calculation of the average brightness value of the displayed image.
  • the brightness of 3 pixels is less than 10
  • the average brightness value is calculated by dividing the sum of the brightness of the remaining 7 pixels by 10. The result is the brightness of the modeled image average value.
  • the step of substituting Lmax1 and Lavg1 into the brightness compensation factor model, and calculating the brightness compensation factor includes steps S4036 to S4037:
  • Step S40371 calculate the calibration points index0, index1, index2, index3 of (Lmax1, Lavg1), and the weight coefficients weight0, weight1, weight2, weight3 corresponding to the calibration points;
  • Step S40372 traverse the brightness compensation factor model, and determine the brightness compensation factors date0, date1, date2, and date3 corresponding to index0, index1, index2, and index3;
  • Step S40373 according to Obtain the brightness compensation factor.
  • step_h
  • index_x (Lavg ⁇ step_h)>>14;
  • m 0 (step_h ⁇ Lavg)&0x3fff;
  • m 1 (1 ⁇ 14)-m 0 ;
  • step_v
  • index_y (Lmax ⁇ step_v)>>14;
  • n 0 (step_v ⁇ Lmax)&0x3fff;
  • n 1 (1 ⁇ 14)-n 0 ;
  • index0 index_y ⁇ N+index_x
  • index1 index_y ⁇ N+(index_x+1);
  • index2 (index_y+1) ⁇ N+index_x;
  • index3 (index_y+1) ⁇ N+(index_x+1);
  • weight0 (m 1 ⁇ n 1 )>>12;
  • weight1 (m 0 ⁇ n 1 )>>12;
  • weight2 (m 1 ⁇ n 0 )>>12;
  • weight3 (m 0 ⁇ n 0 )>>12.
  • step_h is the value step size in the average direction
  • step_v is the value step size in the maximum value direction
  • N is the number of relationship curves.
  • Lavg1 is calculated to be 30 and Lmax1 is 60, the average brightness and maximum brightness of the displayed image form a point (30, 60).
  • the modeled image uses Lavg2 and Lmax2 to establish table entries, please refer to Figure 18 for details. Among them, the table entry is established with Lavg2 as the abscissa and Lmax2 as the ordinate.
  • the determination process of the calibration point of (30, 60) is: determine the two Lavg2 values adjacent to 30 in the table item, namely 25 and 51; and the two Lmax2 values 51, 51, adjacent to 60 in the table item 76, consists of four calibration points: index0, index1, index2, and index3.
  • step_h 160
  • m 0 (160 ⁇ 30)&0x3fff;
  • m 1 (1 ⁇ 14)-m 0 ;
  • step_v 160
  • n 0 (160 ⁇ 60)&0x3fff
  • n 1 (1 ⁇ 14)-n 0
  • index0 index_y ⁇ 11+index_x
  • index1 index_y ⁇ 11+(index_x+1);
  • index2 (index_y+1) ⁇ 11+index_x;
  • index3 (index_y+1) ⁇ 11+(index_x+1).
  • index0 is (25,51); index1 is (51,51); index2 is (25,76); index3 is (51,76); determined by the brightness compensation factor model shown in Figure 18, (25 , 51), (51, 51), (25, 76), (51, 76)
  • the weight coefficients corresponding to the four calibration points are:
  • weight_0 (m 1 ⁇ n 1 )>>12;
  • weight_1 (m 0 ⁇ n 1 )>>12;
  • weight_2 (m 1 ⁇ n 0 )>>12;
  • weight_3 (m 0 ⁇ n 0 )>>12;
  • S404 Calculate the brightness driving signal corresponding to each frame of display image according to the brightness compensation factor.
  • the step of calculating the brightness driving signal corresponding to each frame of display image according to the brightness compensation factor includes:
  • M be the maximum value of the brightness of the display device.
  • an 8-bit channel display device includes 256 brightnesses, where the maximum value of the brightness is 255, then M is 255.
  • a display device with a 10-bit channel includes 1024 brightness, and the maximum brightness value is 1023, so M is 1023.
  • the brightness driving signal is the maximum value of the brightness of the display device; the brightness value may exceed the range after the enhancement process, and needs to be limited to the data range. Generally, if it is 8bit data, if the current brightness value is multiplied by the respective y (brightness compensation factor) After the brightness value is greater than 255, the output brightness value is 255.
  • the second aspect of the embodiments of the present application shows a brightness driving method, which is applied to the first panel of a dual-panel display device. Referring to FIG. 19, the method includes steps S601-S605:
  • S601 Determine a brightness value set of a display image, where the brightness value set includes the brightness value of each pixel of the display image;
  • S602 Divide the pixel point brightness set into a preset number of regions, and generate a region brightness value set, where each region includes at least one pixel point brightness value;
  • the data of 4 points is down-sampled into data of one point, that is, the 3840*2180 pixels are divided into 1920*1080 small areas, and each area is shown in FIG. 20.
  • S603 Determine the maximum value and the average value of each area brightness value in the area brightness value set respectively.
  • the calculation method of the area brightness includes steps S6031 to S6032:
  • S6031 Calculate Py-sum in the area, and Py-avg, determine Py-max, Py-mid in the area, where Py-sum is the sum of pixel brightness, Py-max is the maximum pixel brightness, Py-avg It is the average value of pixel brightness, and Py-mid is the median value of pixel brightness.
  • the method for determining Py-max and Py-mid is: arrange Y1, Y2, Y3, Y4 in ascending order or in descending order to determine Py-max.
  • the median value can be two The average of the brightness data, or any one of the two brightness data in the middle.
  • the embodiment of the present application shows a Py-mid displacement value method, which avoids the process of sorting the brightness of pixels, reduces the data processing volume of the processor, and improves the overall calculation rate .
  • the specific calculation process includes steps S60321-S60323:
  • Step S60321 Calculate Py-sum in the area, and Py-avg, determine Py-max, Py-min in the area, where Py-sum is the sum of pixel brightness, Py-max is the maximum value of pixel brightness, and Py -avg is the average value of pixel brightness, Py-min is the minimum value of pixel brightness;
  • the 3840*2180 pixel brightness of the displayed image is combined into 1920*1080 area brightness; 1920*1080 area brightness constitutes the area brightness set, and the corresponding display screen brightness is the set of 1920*1080 area brightness.
  • the embodiment of this application calibrates the brightness of 1920*1080 areas. Specifically, each value or some values of the area brightness set needs to reach the target value (instrument measurement value), and the brightness data reaching the target value is filled in the area brightness In the collection, if the displayed image is to be accurate, the brightness of each area needs to be calibrated.
  • Engineering realization generally adopts calibration of certain fixed sampling points. After the sampling points are determined (equal or unequal intervals), other brightness values are obtained by interpolation or data fitting methods.
  • S604 Calculate an area brightness compensation factor according to the maximum value and the average value of each area brightness value
  • the brightness compensation factor shown in the embodiment of the present application may be an overall brightness compensation factor or a regional brightness compensation factor.
  • the corresponding compensation method is the overall brightness enhancement method or the area brightness enhancement method.
  • This maximum value is not the largest of all brightness values, but the maximum value in the statistical sense. It is generally the number of pixels found from 255 gray scale to 0 gray scale after the statistics are over. The level that is not zero and the number of pixels contained in each gray level needs to exceed a certain threshold (for example, 0.1% of the total number).
  • the gray level pixels The number of pixels is added to the number of pixels of the next level, until the number of pixels of the first level that meets the conditions is found; this gray level is the maximum value; the calculation of the average value of the brightness in the displayed image Lavg1, if a The brightness values of the pixels of the displayed image are all accumulated and then divided by the number of pixels.
  • the accumulated data bit width will generally overflow, especially when the data bit width is 10bit and 12bit, in order to facilitate the calculation, you can calculate each row Then calculate the average brightness of n rows, and then calculate the average brightness of the n rows to obtain the average brightness of the entire display image.
  • the method of constructing the brightness compensation factor model is the same as the method of constructing the brightness compensation factor model in the foregoing embodiment. For details, refer to the foregoing embodiment.
  • Respectively enhance the data of regional brightness index brightness may exceed the range and need to be limited to the data range.
  • the enhanced brightness data may exceed the range and need to be limited to the data range.
  • the brightness data is multiplied by the respective y (brightness compensation factor) If the data is greater than 255, the output brightness data is 255.
  • the 3840*2180 pixels of the displayed image are converted into 1920*1080 regions.
  • the embodiment of this application calculates the brightness compensation factor corresponding to each region. ,specific:
  • S605 Calculate the brightness driving signal corresponding to each area according to the area brightness compensation factor and the area brightness value.
  • the area brightness is enhanced, and the specific calculation method of the brightness drive signal is each area brightness * brightness compensation factor.
  • the brightness compensation factor shown in the embodiment of the present application may be an overall brightness compensation factor or a regional brightness compensation factor.
  • the corresponding compensation method is the overall brightness enhancement method or the area brightness enhancement method.
  • the step of calculating the brightness driving signal corresponding to each area according to the area brightness compensation factor and the area brightness includes:
  • the brightness driving signal is the maximum value of the brightness of the display device
  • the brightness driving signal is calculated according to the area brightness compensation factor and the area brightness.
  • the enhanced brightness data may exceed the range and needs to be limited to the data range.
  • the output brightness data is 255.

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Computer Hardware Design (AREA)
  • General Physics & Mathematics (AREA)
  • Theoretical Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Liquid Crystal Display Device Control (AREA)
  • Control Of Indicators Other Than Cathode Ray Tubes (AREA)

Abstract

一种对比度提升算法及双面板显示装置，对比度提升算法包括：接收显示图像各第二像素点的RGB值，根据各第二像素点的RGB值，确定各第一像素点的亮度值，其中，第二像素点位于双面板显示装置的第二面板（4，300），第一像素点位于第一面板（3，200），第一面板（3，200）位于发光源（1）和第二面板（4，300）之间（S1）；根据各第一像素点的亮度值，进行局部区域亮度值统计和全局图像亮度值统计，确定局部亮度调整因子和全局亮度调整因子（S2）；根据各第一像素点的亮度值、局部亮度调整因子和全局亮度调整因子，计算对应第一像素点的亮度驱动信号，其中，亮度驱动信号用于调整第一面板（3，200）对应像素点的透光率，全局亮度调整因子用于调整第一面板（3，200）对应像素点的输出亮度值（S3）。

Description

一种对比度提升算法及双面板显示装置
相关申请的交叉引用
本申请要求在2019年4月4日提交中国专利局的、申请号为201910272176.5、发明名称为“一种对比度提升算法及双面板显示装置”的中国专利申请的优先权，其全部内容通过引用结合在本申请中。
技术领域
本公开涉及显示技术领域，特别涉及一种对比度提升算法及双面板显示装置。
背景技术
显示(Liquid Crystal Display，LCD)面板本身不具有发光特性，所以必须在显示面板后面加上一个发光源，由发光源为LCD面板提供背景光，使得LCD面板能够显示画面。图1为一个显示装置的结构示意图，其中，显示装置包括：发光源1和LCD面板2，发光源1为LCD面板2提供背景光，使得LCD面板2能够显示画面。
当面板上调节亮度时，一般需要从RGB坐标系转换到YCbCr坐标系、YUV坐标系、HSV坐标系或者HIS坐标系中，将亮度和色度分别增强处理，以达到全局对比度的调节。通常，一个显示画面的不同局部区域适用不同亮度的背景光，例如，图2为一个显示画面，其中，第一显示图像局部区域为低亮度的画面，适用低亮度的背景光，第二显示图像局部区域为高亮度的画面，适用高亮度的背景光，用对比度提升算法处理彩色信号时，往往不会考虑帧与帧之间的亮度差异，显然，在单一发光源下，通过LCD面板调节显示对比度无法满足上述需求。
发明内容
基于上述技术问题，本公开的目的在于提供一种对比度提升算法及双面板显示装置。
本公开第一方面示出一种对比度提升算法，应用于双面板显示装置，包括：接收显示图像各第二像素点的RGB值，根据所述各第二像素点的RGB值，确定各第一像素点的亮度值，其中，所述第二像素点是位于所述双面板显示装置的第二面板的像素，所述第一像素点是位于所述双面板显示装置的第一面板的像素，所述第一面板位于发光源和所述第二面板之间；根据各第一像素点的亮度值，进行局部区域亮度值统计和全局图像亮度值统计，确定局部亮度调整因子和全局亮度调整因子；根据各第一像素点的亮度值、局部亮度调整因子和全局亮度调整因子，计算对应第一像素点的亮度驱动信号，其中，所述亮度驱动信号用于调整第一面板对应像素点的透光率，全局亮度调整因子用于调整第一面板对应像素点的输出亮度值。
在一些实施方式中，所述根据各第一像素点的亮度值、局部亮度调整因子和全局亮度调整因子，计算对应第一像素点的亮度驱动信号的步骤包括：根据局部亮度调整因子，对第一像素点的亮度值拉伸调整，生成局部亮度调整值，根据全局亮度调整因子，对第一像素点的亮度值拉伸调整，生成全局亮度调整值；根据所述局部亮度调整值和全局亮度调整值，计算对应第一像素点的亮度驱动信号。
在一些实施方式中，所述全局亮度调整因子包括：全局亮度上调因子和全局亮度下调因子，所述根据全局亮度调整因子，对第一像素点的亮度值拉伸调整，生成全局亮度调整值的步骤包括：根据各第一像素点的亮度值，计算显示图像的亮度平均值；对于复数个第一像素点中的一个第一像素点，如果所述第一像素点的亮度值小于显示图像的亮度平均值，根据所述全局亮度下调因子，下调所述第一像素点的亮度值，生成全局亮度调整值；如果所述第一像素点的亮度值大于显示图像的亮度平均值，根据所述全局亮度上调因 子，上调所述第一像素点的亮度值，生成全局亮度调整值。
在一些实施方式中，所述局部亮度调整因子包括：局部亮度上调因子和局部亮度下调因子，所述根据局部亮度调整因子，对第一像素点的亮度值拉伸调整，生成局部亮度调整值的步骤包括：对于任意第一像素点，以该第一像素点位置为中心m*n个像素块，构成局部区域，局部区域的亮度值包括：所述m*n个像素的亮度值；根据局部区域的亮度值，计算局部区域的亮度平均值；如果第一像素点的亮度值小于局部区域的亮度平均值，则根据局部亮度下调因子，下调所述第一像素点的亮度值，生成局部亮度调整值；如果所述第一像素点的亮度值大于局部区域的亮度平均值，根据局部亮度上调因子，上调所述第一像素点的亮度值，生成局部亮度调整值。
在一些实施方式中，根据所述局部亮度调整值和全局亮度调整值，计算对应第一像素点的亮度驱动信号的步骤包括：根据第一像素点对应的局部区域亮度值，计算局部亮度权重系数；根据局部亮度调整值，以及，局部亮度权重系数，计算局部亮度输出值，根据全局亮度调整值，以及，全局亮度权重系数，计算全局亮度输出值，其中，所述局部亮度权重系数与所述全局亮度权重系数的和为1；根据所述局部亮度输出值，以及，全局亮度输出值，计算对应第一像素点的亮度驱动信号。
在一些实施方式中，所述局部亮度权重系数的计算包括：选取N个局部建模区域，所述局部建模区域包括：第一建模像素点的建模亮度值，以及，第一建模像素点邻域的邻域像素亮度值，以及，第一建模像素点对应的局部建模亮度权重系数；根据建模亮度值，以及，邻域像素亮度值，计算第一建模像素点的建模亮度复杂度；根据所述建模亮度复杂度与局部建模亮度权重系数，构建第一局部亮度权重系数曲线；对于复数个第一像素点中的任意一个，根据第一像素点对应的局部区域亮度值，计算所述第一像素点的复杂度，根据所述第一像素点的复杂度，以及，第一局部亮度权重系数曲线，计算所述第一建模像素点对应的局部亮度权重系数。
在一些实施方式中，所述局部亮度权重系数的计算包括：选取N个局部建模区域，所述局部建模区域包括：局部建模区域的亮度值，以及，第二建模像素点对应的局部建模亮度权重系数，所述局部建模区域的亮度值包括：第二建模像素点的建模亮度值，以及，第二建模像素点邻域的邻域像素亮度值；统计局部建模区域中各亮度值出现的建模频数，生成第一建模频数集合；遍历第一建模频数集合，删除小于预置频数的第一建模频数，生成第二建模频数集合；统计第二建模频数集合中包含的亮度值的建模数量，根据所述建模数量与局部建模亮度权重系数，构建第二局部亮度权重系数曲线；对于复数个第一像素点中的任意一个第一，统计第一像素点对应的局部区域亮度值中频数大于预置频数的亮度值的数量，根据所述数量，以及，第二局部亮度权重系数曲线，计算所述第一像素点对应的局部亮度权重系数。
在一些实施方式中，所述局部亮度权重系数的计算包括：选取N个局部建模区域，所述局部建模区域包括：第三建模像素点的建模亮度值，与第三建模像素点接壤的第三建模像素点的接壤亮度值，以及，第三建模像素点对应的局部建模亮度权重系数；根据所述建模亮度值和所述接壤亮度值，计算第三建模像素点的建模亮度特征；根据所述建模亮度特征与局部建模亮度权重系数构建第三局部亮度权重系数曲线；对于复数个第一像素点中的一个第一像素点，计算所述第一像素点的亮度特征，根据所述第一像素点的亮度特征，以及，第三局部亮度权重系数曲线，计算所述第一像素点对应的局部亮度权重系数。
在一些实施方式中，所述方法还包括：根据复数个第二像素点的RGB值，进行局部区域的RGB值统计，确定局部彩色调整因子；根据第二面板的全局的第二像素点的RGB值，以及，第二面板的全局图像亮度值统计，确定全局彩色调整因子；
根据各第二像素点的RGB值、局部彩色调整因子和全局彩色调整因子，计算对应第二像素点的彩色驱动信号，所述彩色驱动信号用于调整第二面板 对应所述第二像素点的RGB值。
本公开的第二方面提供一种双面板显示装置，所述装置包括：处理器，第一面板，与所述处理器相连接并且配置为接收亮度驱动信号，根据亮度驱动信号调整对应第一像素点的透光率，以及第二面板，与所述处理器相连接并且配置为接收彩色驱动信号，根据彩色驱动信号调整对应第二像素点的RGB值；所述处理器，配置为执行：接收显示图像各第二像素点的RGB值，根据所述各第二像素点的RGB值，确定各第一像素点的亮度值，其中，所述第二像素点是位于所述双面板显示装置的第二面板的像素，所述第一像素点是位于所述双面板显示装置的第一面板的像素，所述第一面板位于发光源和所述第二面板之间；根据各第一像素点的亮度值，进行局部区域亮度值统计和全局图像亮度值统计，确定局部亮度调整因子和全局亮度调整因子；根据各第一像素点的亮度值、局部亮度调整因子和全局亮度调整因子，计算对应第一像素点的亮度驱动信号，其中，所述亮度驱动信号用于调整第一面板对应像素点的透光率，全局亮度调整因子用于调整第一面板对应像素点的输出亮度值。
附图说明
为了更清楚地说明本公开和相关技术的实施例，下面将对实施例中所需要使用的附图作简单地介绍，显而易见地，下面描述中的附图仅仅是本公开的一些实施例，对于本领域普通技术人员来讲，在不付出创造性劳动的前提下，还可以根据这些附图获得其他的附图。
图1为显示装置的结构示意图；
图2为一帧显示画面的图像亮度区域划分的示意图；
图3为本公开实施例提供的双面板显示装置的结构示意图；
图4为本公开实施例提供的双面板显示装置的第一面板呈现不同透光区域的示意图；
图5为本公开实施例提供的双面板显示装置的分解结构示意图；
图6为本公开另一实施例提供的双面板显示装置的分解结构示意图；
图7为本公开实施例的双面板显示装置的原理框图；
图8为本公开实施例示出的双面板显示装置的控制系统原理框图；
图9为本公开实施例示出的多分区背光控制中多路背光驱动原理框图；
图10为本公开实施例示出的背光值的增益调整曲线示意图；
图11为本公开实施例示出的双面板显示装置的控制系统细化原理框图；
图12为本公开实施例示出的一种对比度提升算法的示意图；
图13为根据本公开实施例示出的9*9的邻域的示意图；
图14为根据本公开实施例示出的亮度值调整曲线的示意图；
图15为根据本公开实施例示出的一种亮度驱动方法的流程图；
图16为根据本公开实施例示出的Lmax2＝25关系曲线的示意图；
图17为根据本公开实施例示出的亮度补偿因子模型的示意图；
图18为根据本公开实施例示出的表项的示意图；
图19为根据本公开另一实施例示出的一种亮度驱动方法的流程图；
图20为根据本公开实施例示出的显示图像的区域的示意图。
具体实施方式
下面将结合本公开实施例中的附图，对本公开实施例进行清楚、完整的描述，显然，所描述的实施例仅仅是本公开一部分实施例，而不是全部的实施例。基于本公开中的实施例，本领域普通技术人员在没有做出创造性劳动前提下所获得的所有其他实施例，都属于本公开保护的范围。
在本公开的描述中，需要理解的是，术语“中心”、“上”、“下”、“前”、“后”、“左”、“右”、“竖直”、“水平”、“顶”、“底”、“内”、“外”等指示的方位或位置关系为基于附图所示的方位或位置关系，仅是为了便于描述本公开和简化描述，而不是指示或暗示所指的装置或元件必须具有特定的方位、以特定的方位构造和操作，因此不能理解为对本公开的限制。
在本公开的描述中，需要说明的是，除非另有明确的规定和限定，术语“安装”、“相连”、“连接”应做广义理解，例如，可以是接触连接，也可以是可拆卸连接，或一体地连接；对于本领域的普通技术人员而言，可以具体情况理解上述术语在本公开中的具体含义。
本申请实施例中：VBO(Vertex Buffer Objects，顶点缓冲对象)，顶点缓冲对象VBO是在显卡存储空间中开辟出的一块内存缓存区，用于存储顶点的各类属性信息，如顶点坐标，顶点法向量，顶点颜色数据等。
RAM(Random Access Memory，主存)，也叫主存，是与CPU直接交换数据的内部存储器。它可以随时读写，而且速度很快，通常作为操作系统或其他正在运行中的程序的临时数据存储介质。
SPI(Serial Peripheral Interface，串行外设接口)。
在单个LCD面板无法实现高对比度的亮度调节的情况下，使用双面板结构，上面板负责彩色信号的处理，下面板负责高对比度的增强。双面板显示装置的结构如图3所示，其包括：发光源1，第一面板3，以及，第二面板4。其中，第一面板3位于发光源1和第二面板4之间。可选的，第二面板4用于RGB细节处理和图像补偿，第一面板3用于通过不同分区的像素点的透过率进行对比度增强。第一面板3每个透光区域的透光率可进行调节，因此，发光源1发出的光透过第一面板3的不同区域后呈现不同亮度，获得一幅显示画面不同区域背景光强度不一致的效果。
示例性的，当一帧图像中，左半部分区域为暗场景，而右半部分区域为亮场景时，为体现高对比度，应将第二面板中，左半部分的图像对应的区域亮度降低，右半部分的图像对应的区域亮度提高。如图4为第一面板呈现不同透光区域的示意图，其中，第一面板3的第一透光区域和第二透光区域对应图像中的暗场景部分和亮场景部分。第一透光区域的光透过率为20％，第二透光区域的光透过率为80％，发光源1发出的光透过第一面板3为LCD面板2提供背景光，这时，LCD面板2与第一透光区域相对应的区域背景光暗，LCD面板2与 第二透光区域相对应的区域背景光亮。
可选的，双面板显示装置包括依次层叠的背光模组100、第一面板200、第二面板300和粘合层400。图5和6是根据本公开实施例的双面板显示装置的结构示意图；图7是本公开实施例的双面板显示装置的原理框图。
参照图5、6和7可知，背光模组100用于提供光源以发射光线，第一面板200为控光面板，用于控制来自背光模组100的光线进入第二面板300的光通量，第二面板300为彩色面板，用于显示图像，粘合层400用于将第一面板200和第二面板300进行粘合固定为一体，形成一体面板。
沿着双面板显示装置中的AA方向，第一面板200依次包括邻近背光模组100的第一偏光片201、第一液晶光阀层202和第二偏光片203，第一偏光片201和第二偏光片203的透光轴相互垂直，来自背光模组100的光线经过第一偏光片201后变为第一偏振光，第一偏振光进入到第一液晶光阀层202，根据显示图像内容，通过电压控制第一液晶光阀层202内的液晶转动，使第一偏振光的方向随之发生旋转，发生角度旋转后的第一偏振光进入到第二偏光片203变为第二偏振光。因第一偏光片201和第二偏光片203的透光轴相互垂直，由此实现对进入第二面板300的光通量的控制。需要说明的是，第一面板200中不包括滤光片，若来自背光模组100中的光线为白光，第一面板200为单色面板。
沿着双面板显示装置中的A-A方向，第二面板300依次包括邻近第一面板200的第三偏光片301、第二液晶光阀层302、滤光片303和第四偏光片304，第三偏光片301和第四偏光片304的透光轴相互垂直。第二偏光片203与第三偏光片301的透光轴相互平行。来自第一面板200的第二偏振光进入到第三偏光片301时，第二偏振光的偏振方向不发生旋转，而后进入第二液晶光阀层302，根据显示图像内容，通过电压控制第二液晶光阀层302内的液晶转动，使第二偏振光的偏振方向随之发生旋转，发生角度旋转后的第二偏振光进入到滤光片303，变为彩色光，而后彩色光进入到第四偏振片304变为第三偏振光，因第三偏光片301和第四偏光片304的透光轴相互垂直，由此实现对彩色光线的光通 量的控制，实现对图像的彩色显示。
因外界水汽进入第一面板200和第二面板300之间，会导致在两个面板之间因温度变化凝固成水珠而影响显示效果，粘合层400采用面贴合的方式将第一面板200和第二面板300粘合固定在一起，面贴合为全贴合，即整个面上布设胶层。为了不影响光线的传输，粘合层400采用透明胶层，例如可采用OCA(Optically Clear Adhesive)光学胶或硅胶OCR(Optical Clear Resin)。为了保证粘合效果和避免双面板过厚，粘合层的厚度在0.15-0.75mm之间，优选0.25-0.5mm。
需要说明的是，第一面板200可以包括一个偏光片，例如第二偏光片203，第二面板300可以包括一个偏光片，例如第三偏光片301，图5中示出的第一面板200和第二面板300分别具有两个偏光片的情形。本公开另一实施例中，第一面板200和第二面板300共用一个偏光片，图6中示出的是两者共用一个偏光片的情形，因缺省一偏光片，在满足显示需要的情况下，可降低显示装置的成本。如图6所示，与图5不同的是，双面板显示装置中不包括第三偏光片301，在该显示装置中，第一偏光片201的透光轴与第二偏光片203的透光轴相互垂直，第二偏光片203的透光轴和第四偏光片304的透光轴相互垂直。与图5中所示的双面板显示装置的光路原理近似，来自第一面板200的第二偏振光直接进入第二液晶光阀层302，根据显示图像内容，通过电压控制第二液晶光阀层302内的液晶转动，使第二偏振光的方向随之发生旋转，发生角度旋转后的第二偏振光进入到滤光片303，变为彩色光，而后彩色光进入到第四偏光片304变为第三偏振光，因第二偏振光片203和第四偏光片304的透光轴相互垂直，由此实现对彩色光线的光通量的控制，实现对图像的彩色显示。在图6所示的双面板显示装置中，粘合层400位于第二偏光片203与第二液晶光阀层302之间。粘合层400的位置不限于此，粘合层400也可位于第一液晶光阀层202和第二偏光片203之间。
第一液晶光阀层202和第二液晶光阀层302的结构类似，包括上基板、下 基板以及位于上基板和下基板之间的液晶盒。
第一面板200和第二面板300中的液晶光阀层均包括多个液晶盒，与第二面板300(彩色面板)中控光的原理相似，第一面板200可实现单像素作为独立光阀，实现像素级的控光，相比于只有一个面板的显示装置来说，双面板显示装置具有两层像素级的控光，实现了更为精细的控制。由于第一面板200实现了像素级的控光，相比于单面板显示装置，第一面板200和第二面板300的配合，可以大幅度降低黑画面的亮度，以解决单面板显示装置中因液晶光阀层无法做到绝对不透光导致的黑画面具有一定亮度的问题，显著提高了液晶显示装置静态对比度。
因第一面板200是利用偏光片和液晶的旋转来实现控光，而偏光片的透过率在38％-48％，如此会降低显示装置的整体光透过率。故在本公开中，通过使第一面板200的分辨率小于第二面板300的分辨率，即第一面板200中的像素点数量小于第二面板300中像素点的数量，避免因使用双层面板使得来自背光模组的光线经过第一面板的透光率下降导致显示装置的显示的亮度不足。第二面板300中像素点的数量与第一面板200中像素点的数量之比不小于4：1，例如：4：1、16：1，即当第二面板300的分辨率为8K时，第一面板200的分辨率可为4K或2K，当第二面板300的分辨率为4K时，第一面板200的分辨率可为2K。
具体的，本公开实施例中第一面板200的分辨率为1920*1080，第二面板300的分辨率为3840*2160。
为了进一步提升画面的对比度，本公开实施例中，如图7所示，背光模组100中采用多背光分区控制方式，即将背光模组100中的背光源划分为多个背光分区101，依据显示图像信息中包含的亮度信息动态地改变每个背光分区101的亮度，图像中的明亮部分对应较高的背光亮度，图像中的暗场景部分对应较低的背光亮度，相比于背光模组提供恒定不变的背光，通过动态调整背光亮度的方法可以解决纯黑场仍有微弱漏光和功耗大的问题，进一步提高画面的明 暗对比度，提高画质。
双层面板显示装置中，双层面板和背光分区控制的结合进一步解决了暗场画面不够黑的问题，更好的提高了画面的显示对比度。
接下来，介绍一下双面板显示装置对双面板和多背光分区的控制。
图8是双面板显示装置中控制系统原理框图，如图8所示，双面板显示装置包括一主芯片SOC(System on Chip)，双面板处理器，第一面板，第一面板时序控制器(Timing Controller，TCON)，第二面板、第二面板时序控制器，背光控制微处理器(Microcontroller Unit，MCU)、背光驱动器、背光灯。
主芯片SOC输出图像信号，双面板处理器接收该图像信号，双面板处理器被配置为响应于上述图像信号产生用于第一面板的调光数据，调光数据发送到第一面板时序控制器，第一面板时序控制器依据调光数据对第一面板驱动控制；双面板处理器还被配置为响应于上述图像信号产生用于第二面板的图像数据，图像数据发送到第二面板时序控制器，第二面板时序控制器依据图像数据对第二面板进行控制显示；双面板处理器还被配置响应于上述图像信号产生用于背光控制的背光数据，背光数据发送到背光控制MCU，背光控制MCU产生占空比、电流等调光信息并发送到背光驱动器，背光驱动器依据占空比、电流等调光信息实现对背光灯的驱动控制。
以下以第一面板的分辨率为1920*1080(2K)，第二面板的分辨率为3840*2160(4K)为例进行说明。
调光数据的产生过程：双面板处理器接收来自主芯片SOC的4K图像数据信号，处理器首先将图像中像素点的RGB值转换为像素点的第一亮度值(Y)，然后对Y下采样处理，生成对应于第一面板像素点的第二亮度值，即实现4K转2K的降分辨率处理，接着根据第二亮度值进行Y对比度提升，其中Y对比度提升包括对局部区域和整体区域亮度的提升，具体为根据第二亮度值，进行局部区域亮度值统计和全局图像亮度值统计，确定局部亮度调整因子和全局亮度调整因子，根据第二亮度值、局部亮度调整因子和全局亮度调整因子进行Y 对比度提升；然后根据不同对比度的画面进行中高亮度部分增强处理，提升中高亮度部分的整体亮度；而后对中高亮度部分进行边缘模糊处理，通过边缘模糊处理使得帧内不同亮度区域之间平滑过渡。本公开实施例中通过空间滤波方式，对亮度进行平滑处理，以解决因第一面板中分立的液晶盒以及液晶盒之间的隔离柱导致的光波波形不平缓。最后生成的调光数据通过LVDS(Low Voltage Differential Signaling)接口传输到第一面板的时序控制器(TCON)，第一面板时序控制器依据调光数据对第一面板驱动控制。
图像数据的产生过程：双面板处理器接收来自主芯片SOC的4K图像数据信号后，处理器会针对像素点进行RGB对比度提升，复用用于产生调光数据的全局图像亮度统计值、根据全局图像RGB值和局部区域RGB数值进行整体和局部的RGB对比度增强处理，使黑的部分更黑，亮的部分更亮，提升画面的整体对比度；且为了在第一面板亮度减低时更好保持中低亮部分的亮度，根据第一面板的亮度信息，对图像进行相应的图像补偿，使显示画面经由第一面板损失的亮度在第二面板上得到补偿。最后生成的图像数据通过VBO(V-By-One)接口传输到第二面板的时序控制器(TCON)，第二面板时序控制器依据调光数据对第二面板驱动控制。
本公开实施例中将多分区控制技术和双面板技术进行了结合使用，若将传统的背光控制直接与双面板的平台结合在一起，两个模块是完全独立的，背光的控制没有考虑到双面板平台的特殊性(第一面板会降低背光的透过率)，背光控制很容易偏暗，且当背光分区越多，该问题表现也就越严重。由此，本公开中背光数据的产生过程如下：
在第一面板的空间滤波之后加上一级下采样模块，下采样模块实现将原来1920x1080直接下采样到目标的背光分区数，而后进行时间滤波，即将当前帧的背光值与上一帧的背光值进行混合(blending)的处理得到混合数据，而后写入到RAM中，可从RAM中将上述混合数据读出，最后得到背光数据，得到的背光数据通过SPI接口传输到背光控制MCU，背光控制MCU产生占空比、电流 等调光信息并发送到背光驱动器，背光驱动器依据占空比、电流等调光信息实现对背光灯的驱动控制。
通过以上方式实现了多分区背光控制和双面板技术的结合使用，且通过复用数据使得局部背光灯尽可能的亮，保证双面板显示装置整体透过更多的亮度以及节省了硬件资源。
图9为多分区背光控制中多路背光驱动原理框图，如图9所示，背光控制MCU处理每个背光分区的亮度信息，查找分区映射单元预存的映射表，同时根据查找到的实际分区坐标位置调整每个背光分区的占空比。分区占空比的调整方式包括，背光控制MCU将每个背光分区的背光占空比数据发送给背光驱动器，具体为PWM(Pulse-Width Modulation)驱动器，由PWM驱动器产生对应的PWM控制信号来驱动背光源(LED灯串)。必要时，背光处理单元可以向PWM驱动器发送电流数据，PWM驱动器根据电流数据和预设参考电压Vref来调整电流。通常PWM驱动器由多颗芯片级联而成，每颗芯片又可以驱动多路PWM输出电流给LED灯串。
进一步地，在双面板显示装置中，因第一面板会降低背光的透过率，会使得背光控制容易偏暗，对于亮场景的画面亮度不利，因此，在本公开实施例中，在分区背光控制的基础上，使用LED背光峰值增强技术，通过动态地提高亮场景和常规显示画面的背光峰值亮度来突出表现画面中的明亮部分，达到进一步提高画面对比度和画面层次感的效果。
如图10所示，为本公开实施例中的背光值的增益调整区域示意图，其中横坐标为背光值，取值范围为[0，255]，纵坐标为增益值，取值范围为[1,正无穷)，然而，实际执行过程中，可根据实际功率设置的需求，将所述增益值取值范围设置为[1,2]；且所述增益值并不限于整数，还可以为非整数。所述增益调整曲线可以划分为低亮增强区间、高亮增强区间和功率控制区间。在背光区域中背光值的平均值较低时，增益值处在低亮增强区间；随着背光区域中显示内容的变化，背光区域中背光值的平均值落在高亮增强区间时，增益值处于高亮增强区 间，可以较好地突出画面中高亮部分；在背光区域中背光值的平均值较高时，由于背光区域中整个画面的亮度足够高，基本不需要再将背光增强，反而由于功率消耗，需要将背光增益效果降低。由于确定的每个背光区域的背光值的平均值不相同，因此，确定出的增益值也不相同，使得显示过程中画面的明暗对比大、层次感明显。
具体的，本申请实施例示出一种双面板显示装置，请参阅图11，所述装置包括：
处理器，与所述处理器相连接的第一面板，以及与所述处理器相连接的第二面板；
处理器接收VBO上传的第二像素点的RGB值，将所述第二像素点的RGB值转换为第二像素点的亮度值(Y)，然后对Y下采样，生成第一像素点的亮度值。一方面，根据第一像素点亮度值，进行局部区域亮度值统计，确定局部亮度调整因子以及局部亮度权重系数；根据局部亮度调整因子以及局部亮度权重系数对第一像素点的亮度值进行局部对比度的拉伸，生成局部亮度输出值；另一方面，根据第一像素点亮度值进行全局图像亮度值统计，确定全局亮度调整因子以及全局亮度权重系数；根据全局亮度调整因子以及全局亮度权重系数对第一像素点的亮度值进行全局对比度的拉伸，生成全局亮度输出值。然后将全局亮度输出值与局部亮度输出值混合，生成亮度驱动信号；所述亮度驱动信号以LVDS信号形式发送至第一面板。
在另一些实施方式中，处理器接收VBO上传的第二像素点的RGB值，根据第二像素点的RGB值，进行局部区域RGB值统计，确定局部彩色调整因子和局部彩色权重系数。所述局部彩色调整因子和局部彩色权重系数，用于对第二像素点的RGB值进行局部对比度的拉伸，生成局部彩色输出值；所述第一像素点亮度值的全局统计结果和第二像素点的全局RGB值的统计结果，还用于对第二像素点的RGB值进行全局对比度的拉伸，生成全局彩色输出值。然后将全局彩色输出值与局部彩色输出值混合，生成彩色驱动信号，所述彩色驱动信号 以VBO信号形式发送至第一面板。
可选择的，以LVDS信号形式传输的亮度驱动信号经过下采样，滤波处理后通过SPI串行外接口发送至发光源(Backlight)，用于调节发光源提供的背景光的亮度。
具体的：所述处理器，用于执行以下步骤S1-S3：如图12所示。
步骤S1，接收显示图像各第二像素点的RGB值，根据所述各第二像素点的RGB值，确定各第一像素点的亮度值，其中，所述第二像素点是位于所述双面板显示装置的第二面板的像素，所述第一像素点是位于所述双面板显示装置的第一面板的像素，所述第一面板位于发光源和所述第二面板之间。
步骤S11，第二像素点的RGB值转换为第二像素点的亮度值；
在计算机中使用最多的RGB彩色空间，分别对应红、绿、蓝三种颜色；通过调配三个颜色分量的比例来组成各种颜色。一般可以使用1、2、4、8、16、24、32位来存储这三种颜色，在本申请实施例中，RGB分量用8位来表示，最大值是255。
一般的RGB值转Y值(亮度值)的转换公式为：
Y＝0.299R+0.587G+0.114B   (1)
在实际应用的过程中，在一些场景中，如果使用上述方法进行计算得到Y值是不合理的，例如，当显示画面为纯蓝场时，RGB值为(0,0,255)，通过上式得到的Y值为29，这样透过的光亮度值相比于纯蓝场下的RGB值(0,0,255)会减少很多。
因此，为使对比度增强，选取R、G、B值中的最大值作为Y值。这样透过的光亮度值相比于纯蓝场(0,0,255)使用转换公式计算得到的Y值会增加很多，RGB值只转Y值时，此时使用RGB值的最大值是合理的，亮度值Y的计算公式如下：
Y＝MAX(R,G,B)   (2)
步骤S12，将第二像素点的亮度值下采样为第一像素点亮度值。
采用上述方法将显示图像各第二像素点的RGB值，转换为第二像素点亮度值，然后对第二像素点亮度值下采样，生成对应的第一像素点的亮度值。
举例说明，本申请实施例控制的是像素点为4K的第二面板，则第二面板有3840*2160个第二像素点。第一面板具有1920*1080个第一像素点。相应的对4K的像素点下采样得到2K像素点，生成1920*1080个小区域，所述第一像素点与所述第二面板小区域一一对应；每个第一像素点的亮度值的计算方式：4K个亮度值使用每四个值缩放为一个值的原理进行缩放；与一般的缩放相同；采用四个像素点的亮度最大值；采用四个像素点的亮度平均值；采用四个像素点的亮度最小值；采用四个像素点的亮度中值，最终生成一个包含1920*1080个第一像素点亮度值的集合。
步骤S2，根据各第一像素点的亮度值，进行局部区域亮度值统计和全局图像亮度值统计，确定局部亮度调整因子和全局亮度调整因子；
步骤S21，所述全局亮度调整因子包括：全局亮度下调因子global_min_y和全局亮度上调因子global_max_y；
其中，global_min_y的计算过程：
遍历所述第一像素点的亮度值集合，确定显示图像的亮度最大值P_frame_max，亮度平均值P_frame_avg，以及，亮度最小值P_frame_min；
具体的，通过遍历所述第一像素点的亮度值集合可以直接得到图像的亮度最大值P_frame_max，亮度最小值P_frame_min，亮度平均值P_frame_avg；该亮度最大值和亮度最小值不是实际值，而是根据统计得出。从低0灰阶(即图像中亮度值为0的亮度值)开始判断0灰阶像素点的个数sum＝gray[0]是否大于预置灰阶值像素点的个数，如果不满足，则从0灰阶像素点的个数累计到1灰阶像素点的个数，即sum_num＝gray[0]+gray[1]，一直到满足条件时停止，此时灰阶值为P_frame_min；同理，从255灰阶开始判断255灰阶像素点的个数sum＝gray[255]是否大于预置灰阶值像素点的个数，如果不满足，则从255灰阶像素点的个数累计到254灰阶像素点的个数，即sum_num＝gray[255]+gray[254]， 一直到满足条件时停止，此时灰阶值为P_frame_max。例如，预设最小灰阶值的像素点个数为8个，当0阶灰度的像素点的个数只有一个，1阶灰度值的像素点为4个，2阶灰度的像素点多于3个时，将亮度最小值P_frame_min设置为2灰阶值。以此来避免干扰和跳变。
其中，global_min_y＝f(P_frame_min)，global_min_y是关于P_frame_min函数，global_max_y＝f(P_frame_max)，global_max_y是关于P_frame_max函数，硬件实现方法可以采用Look up table的方法。
步骤S211，可选择的，利用画面背景的黑场景判定可以计算出全局亮度调整因子，其中，画面背景的黑场景判定：
初始化back_black_near_flag＝0；
计算sum_gray_cont。
具体的sum_gray_cont的计算过程：在对图像进行直方图统计后，发现画面背景的黑场景图像，在亮度值Gray_TH0到Gray_TH1之间分布的像素点的个数sta-gray[k]较多且大于NUM_TH0(预先设置值)，且Gray_TH0到Gray_TH1之间的亮度值数较少，一般不多于阈值数量TH0；根据亮度值分布统计Gray_TH0到Gray_TH1之间的sta-gray[k]，统计出满足sta-gray[k]大于等于NUM_TH0的个数cont；并且统计出cont小于等于TH0条件下sta-gray[k]的累加sum_gray_cont。
例如，设置Gray_TH0＝12，Gray_TH1＝20，NUM_TH0＝3000。则统计亮度值为12，亮度值为13，亮度值为14，亮度值为15，亮度值为16，亮度值为17，统计亮度值为18，亮度值为19，亮度值为20对应像素点的个数sta-gray[k]；统计出sta-gray[k]大于等于3000的亮度值为：亮度值为13，亮度值为14，则sum_gray_cont＝sta-gray[13]+sta-gray[14]。
如果sum_gray_cont大于等于sum_TH(预先设置值)；
则该帧图像判定为属于背景为黑场景的图像，设置back_black_near_flag＝1；
根据back_black_near_flag是否为1，可以采用两个不同f(P_frame_min)计算global_min_y；
如果(back_black_near_flag＝1)，则global_min_y1＝f1(P_frame_min)；
如果(back_black_near_flag＝0)，则global_min_y2＝f2(P_frame_min)；
其中，global_min_y1>global_min_y2，f1和f2为函数曲线。
其中，global_min_y的计算过程：global_min_y＝f(P_frame_min)，其可以为线性调整；例如f(P_frame_min)＝(255-P_frame_min)。类似地，global_max_y的计算过程：global_max_y＝f(p_frame_max)，其可以为线性调整；例如f(P_frame_max)＝(255-P_frame_max)。
也可以采用其他的非线性调整；考虑到硬件实现问题，除法需要LUT方法进行处理，将除法转换成乘法处理。
步骤S22，所述局部亮度调整因子包括：局部亮度下调因子local_min_y和局部亮度上调因子local_max_y；
对于任意第一像素点，以该第一像素点位置为中心选取m*n的像素块，所述m*n个像素块的亮度值，构成局部区域亮度值集合。
每个第一像素点对应一个坐标值(i，j)，以该第一像素点位置为m*n个像素块的中心；如图13所示，该m*n个像素块可以为9*9的块，所述m*n个像素块的亮度值，构成局部区域亮度值集合。
遍历所述局部区域亮度值集合，确定局部区域的亮度最大值P_local_max(i,j)，局部区域的亮度平均值P_local_avg(i,j)，以及，局部区域的亮度最小值P_local_min(i,j)。
通常方法是将所有的位置点数据查找一遍，找出该局部区域的亮度最小值和亮度最大值，以及累加出该局部区域的所有第一像素点的亮度值的和并除以该局部区域第一像素点的总数得到局部区域的亮度平均值。
local_min_y(i,j)的计算过程与global_min_y的计算过程相似，在此便不详细介绍。
其中，local_max_y(i,j)的计算过程与global_max_y的计算过程相似，在此便不详细介绍。
步骤S3，根据各第一像素点的亮度值、局部亮度调整因子和全局亮度调整因子，计算对应第一像素点的亮度驱动信号，其中，所述亮度驱动信号用于调整第一面板对应像素点的透光率，全局亮度调整因子用于调整第一面板对应像素点的输出亮度值。
步骤S31，全局亮度调整值的计算：
对于任意第一像素点的亮度值P(i,j)，如果所述P(i,j)<P_frame_avg，则P_out_global(i,j)＝(P_frame_avg–(P_frame_min-global_min_y))/(P_frame_avg-P_frame_min)*(P(i,j)-P_frame_avg)+P_frame_avg(3)
其中，P_out_global(i,j)为全局亮度调整值，global_min_y为全局亮度下调因子。
对于任意第一像素点的亮度值P(i,j)，如果所述P(i,j)＝P_frame_avg，则
P_out_global(i,j)＝P_frame_avg  (4)
对于任意第一像素点的亮度值P(i，j)，如果所述P(i,j)>P_frame_avg，则
P_out_global(i,j)＝(P_frame_avg–(P_frame_max+global_max_y))/(P_frame_avg-P_frame_max)*(P(i,j)-P_frame_avg)+P_frame_avg  (5)
其中，global_max_y为全局亮度上调因子。
具体调整后的结果如图14所示，其中x轴为P(i，j)，y轴为P_out_global(i，j)。
步骤S32，局部亮度调整值的计算：
对于任意第一像素点的亮度值P(i,j)，如果所述P(i,j)小于P_local_avg(i,j)，则
P_out_local(i,j)＝(P_local_avg(i,j)–(P_local_min(i,j)-local_min_y(i,j)))/(P_local_avg(i,j)–P_local_min(i,j))*(P(i,j)-P_local_avg(i,j))+local_avg(i,j)   (6)
其中P_out_local(i,j)为第二亮度调整值，local_min_y(i，j)为区域亮度下调因子。
如果P(i,j)等于P_local_avg(i,j)，则P_out_local(i,j)＝P_local_avg(i,j)。(7)
如果P(i,j)大于P_local_avg(i,j)，则
P_out_local(i,j)＝(P_local_avg(i,j)–(P_local_max(i,j)+local_max_y(i,j)))/(P_local_avg(i,j)-P_local_max(i,j))*(P(i,j)-P_local_avg(i,j))+P_local_avg(i,j).(8)
步骤S33，亮度驱动信号的计算：
P_out(i,j)＝weight_local(i,j)*P_out_local(i,j)+weight_global*P_out_global(i,j)；
weight_local(i,j)+weight_global＝1；(9)
或：
P_out(i,j)＝weight_local*P_out_local(i,j)+weight_global(i,j)*P_out_global(i,j)+weight_org*P(i,j)；(10)
weight_local(i,j)+weight_global+weight_org(i,j)＝1.(11)
其中，weight_org(i,j)为调整系数，P_out(i,j)为亮度驱动信号，weight_local(i,j)为局部亮度权重系数，weight_global为全局亮度权重系数。
步骤S331，局部亮度权重系数的计算过程如下：
在本公开的一些实施例中，在第一面板上选取N个局部建模区域，所述局部建模区域包括：第一建模像素点的建模亮度值i，以及，第一建模像素点邻域(m*n-1)的领域亮度值，以及，第一建模像素点对应的局部建模亮度权重系数weight_local(i,j) 建模。
局部建模区域还包括建模亮度复杂度，包括：局部建模区域的亮度值i出现的频数hg(i) 建模的平均值A 建模，亮度值i出现的频数hg(i) 建模的能量值Power 建模，以及，亮度值i出现的频数hg(i) 建模的熵值Entropy 建模；
具体的计算过程：利用直方图统计局部建模区域的亮度值i出现的频数hg(i) 建模；
(a)平均值：
Figure PCTCN2020081251-appb-000001
M 建模＝m 建模×n 建模
(b)能量值：Power 建模＝∑ i[h g(i) 建模] 2
(c)熵值：Entropy 建模＝—∑ ig h(i) 建模lgh g(i) 建模
构建weight_local(i,j) 建模＝f(A 建模,Power 建模,Entropy 建模)曲线，即第一局部亮度权重系数曲线；
对于任意第一像素点，根据第一像素点对应的局部区域亮度值，计算所述第一像素点的对应局部区域亮度值i出现的频数h g(i)的平均值A(i,j)，能量值Power(i,j)，以及，熵值Entropy(i,j)，将所述A(i,j)、Power(i,j)、Entropy(i,j)代入weight_local(i,j) 建模＝f(A 建模,Power 建模,Entropy 建模)曲线，计算出所述第一像素点对应的局部亮度权重系数weight_local(i,j)。
在本公开的其他实施例中，在第一面板上选取N个局部建模区域，所述局部建模区域包括：局部建模区域的亮度值，以及，第二建模像素点对应的局部建模亮度权重系数，所述局部建模区域的亮度值包括：第二建模像素点的建模亮度值，以及，第二建模像素点邻域的邻域亮度值；
统计每个局部建模区域中各第二建模像素点的建模亮度值出现的建模频数，生成第一建模频数集合；
遍历所述第一建模频数集合，删除小于预置频数的建模频数，生成第二建模频数集合；
统计第二建模频数集合中包含的建模亮度值的建模数量，根据每个局部建模区域的所述建模数量与局部建模亮度权重系数构建第二局部亮度权重系数曲线；
对于任意第一像素点，统计第一像素点对应的局部区域亮度值中频数大于预置频数的亮度值的数量，根据所述数量，以及，第二局部亮度权重系数曲线，计算所述第一像素点对应的局部亮度权重系数。
具体的，在第一面板上选取N个局部建模区域，分别计算每个局部建模区 域中各亮度值出现的频数h g(i) 建模，生成第一建模频数集合；遍历第一建模频数集合，删除小于预置频数的频数，生成第二建模频数集合；统计第二建模频数集合中包含的亮度值的数量count 建模；构建weight_local 建模＝f(count 建模)曲线，即第二局部亮度权重系数曲线。
对于任意第一像素点，根据第一像素点对应的局部区域亮度值集合，统计各亮度值出现的频数h g(i)，遍历第一频数集合，删除小于预置频数的频数，生成第二频数集合，统计第二频数集合中包含的亮度值的数量count(i,j)，将所述count(i,j)代入weight_local 建模＝f(count 建模)曲线，计算出所述第一像素点对应的局部亮度权重系数weight_local(i,j)。
可以统计h g(i)>NUM_th0的个数count；NUM_th0为预置频数，一般的NUM_th0为3000，此值可以配置(1920x1080的第一面板分辨率为例)；以第一面板的分辨率1920x1080为例，count的范围为0-1920x1080；可以将count设为横坐标的自变量，weight_local(i,j)设为纵坐标的因变量，局部亮度权重系数weight_local(i,j)的数值范围为[0，1]。
对局部建模区域进行直方图统计，资源的消耗还是比较大；为了进一步简化硬件的实现方法，本申请实施例示出另一种局部亮度权重系数weight_local(i,j)的计算方法。
具体的，在第一面板上选取N个局部建模区域，对于局部建模区域中任意一第一像素点(即第三建模像素点)的亮度值为p(i,j) 建模，确定与所述第一像素点接壤的两个第一像素点的亮度值：一号第一像素点的亮度值p(i±1,j) 建模，二号第一像素点的亮度值p(i,j±1) 建模；
根据
p_diff0(i,j) 建模＝|local_pixel(i，j) 建模-local_pixel(i，j±1) 建模|  (12)
p_diff1(i,j) 建模＝|local_pixel(i，j) 建模-local_pixel(i±1，j) 建模|  (13)
Figure PCTCN2020081251-appb-000002
p_avg_diff(i,j) 建模＝p_sum_diff(i,j) 建模/(m×n)；(15)
其中，p_diff0(i,j) 建模和p_diff1(i,j) 建模分别为第一像素点的亮度值与二号第一像素点的亮度值和一号第一像素点的亮度值的差值；通过上式，求得建模亮度特征p_sum_diff(i,j) 建模或p_avg_diff(i,j) 建模。其中，m*n为局部区域亮度值集合中包含的像素点的个数；
构建p_weight_local 建模＝f(p_sum_diff 建模)曲线，或p_weight_local 建模＝f(p_avg_diff 建模)曲线；
对于任意一个第一像素点的亮度值p(i,j)，计算出所述p(i,j)对应的p_sum_diff(i,j)，将所述p_sum_diff(i,j)代入p_weight_local 建模＝f(p_sum_diff 建模)曲线，计算出所述第一像素点对应的局部亮度权重系数weight_local，或，计算出所述p(i,j)对应的p_avg_diff(i,j)，将p_avg_diff(i,j)代入p_weight_local 建模＝f(p_avg_diff 建模)曲线计算出所述第一像素点对应的局部亮度权重系数weight_local。
优选的，局部取样时，如果中心点在图像的比较靠上的几行、靠左几列、或者靠下的几行、靠右几列；模板取的数据超过了图像的范围；模板中使用复制的方法进行；
以模板大小9*9为例，以中心点为(0，0)为例；左上角使用(0，0)点的数据填充；右上角一行和左下角一列的数据分别复制模板的第一行的数据和第一列的数据；右下角的数据直接为原始图像中的数据；数据填充的格式也可以是对称复制，以列为例子，模板包括-4，-3，-2，-1，1，2，3，4列；-4列复制不是1列的数据而是4列的数据，-3列的数据复制3列的数据，-2列的数据复制2列的数据，-1列的数据复制1列的数据；右上角还是复制(0，0)的数据。
可选择的，所述处理器还用于：
根据各第二像素点的RGB值，进行局部区域RGB值统计，确定局部彩色调整因子；根据第二面板的全局RGB值，以及，第二面板的全局图像亮度值统 计，确定全局彩色调整因子；
根据各第二像素点的RGB值、局部彩色调整因子和全局彩色调整因子，计算对应第二像素点的彩色驱动信号，所述彩色驱动信号用于调整第二面板对应所述第二像素点的RGB值。
所述第一面板，用于接收亮度驱动信号，根据亮度驱动信号调整对应第一像素点的透光率；
所述第二面板，用于接收彩色驱动信号，根据彩色驱动信号调整对应第二像素点的RGB值。
由以上技术方案可以看出，本申请实施例示出一种对比度提升算法及双面板显示装置，本公开用于超高清电视画质处理芯片或者Tcon芯片中，也可用于FPGA或者多核的处理器中，完成对双面板亮度的控制，实现多局部区域的背景光控制效果，实现更精确的背景光“分区控制”，在发光源恒定的条件下，可以通过控制第一面板的透光率实现精细的背景光控制，实现更精确的分区控制，以及进一步提高画面的动态对比度。
以下介绍中高亮增强的处理过程。
接收经过Y对比度提升的数据流进行后续处理。具体请参阅图15，本申请实施例示出一种亮度驱动方法，所述方法包括以下步骤S401-S404：
步骤S401，确定显示图像的亮度值集合，其中，所述亮度值集合包括所述显示图像各像素点的亮度；
在计算机中使用最多的RGB彩色空间，分别对应红、绿、蓝三种颜色；通过调配三个颜色分量的比例来组成各种颜色。一般可以使用1、2、4、8、16、24、32位来存储这三种颜色，本申请实施例中，RGB分量用8位来表示，最大值是255。
本申请实施例中，首先获取各像素点的RGB值，然后将RGB值转化为亮度值。
从RGB值到YUV空间的Y值(亮度值)转换公式为：Y＝ 0.299R+0.587G+0.114B。
在实际应用的过程中，在一些场景中，如果使用该方法进行计算得到Y是不合理的，则，选取R、G、B值中的最大值作为Y。例如当显示画面为纯蓝场时(0,0,255)，通过上式得到的Y值为29，这样透过的光亮度值相比于纯蓝场下的RGB值(0,0,255)会减少很多，RGB值只转Y值时，此时使用RGB值的最大值是合理的，亮度值Y的计算公式如下：Y＝MAX(R,G,B)。
每个像素点对应一个像素点亮度，一幅显示图像的亮度表示为像素点亮度集合{Y1，Y2，Y3……}。
步骤S402，根据所述亮度值集合确定所述显示图像中亮度的平均值Lavg1和最大值Lmax1；
值得注意的是，计算出显示图像中亮度的最大值Lmax1，此最大值不是所有亮度值最大的一个，而是统计意义下的最大值，一般是统计结束后，从255灰阶到0灰阶查找到像素个数不为零的那一阶且每个灰阶包含的像素的个数需要超过某个阈值(例如总个数的0.1％),如果该阶像素的个数不满足要求，则将该灰阶像素的个数累加到下一阶的像素的个数，直到找到满足条件的那一阶的像素的个数停止；此灰阶即为显示图像中亮度的最大值；显示图像中亮度的平均值Lavg1的计算，如果将一幅显示图像的像素点的亮度值全部累加后再除以像素点的个数，累加和的数据位宽一般会溢出，特别当数据位宽为10bit和12bit时，为了便于计算，可以先计算每一行的亮度均值，再计算出n个行的亮度均值，然后对n个行的亮度均值进行求取平均值，得到整幅显示图像的亮度的平均值。
实现过程中，通常显示装置采用光混原理进行显示图像的显示，故每一像素又可分为R\G\B三子像素，三子像素对应的亮度不同，则对应的每一像素的亮度不同，在本实施例中进行亮度直方图统计时，每个像素中亮度为该像素中三子像素的原始亮度所对应的亮度的最大值。在进行统计时，仅采用一个像素中亮度最大值的子像素进行统计，相对于统计所有的子像素，统计量和计算量 都小了，从而使统计和计算更加简便和快捷；另一方面在此选用R/G/B三子像素中原始亮度最大的子像素对应的像素亮度为统计量，相对于采用三子像素中原始亮度的最低或中间值对应的像素亮度，最大限度的保留了输入显示图像的原始显示图像信息，从而输入显示图像的信息损失小，显示图像显示效果佳。
步骤S403，根据显示图像中亮度的平均值和最大值计算亮度补偿因子；
具体的，将显示图像中亮度的平均值和最大值代入亮度补偿因子模型，得到亮度补偿因子。
本申请实施例预先构建亮度补偿因子模型，所述亮度补偿因子模型基于建模图像中亮度的最大值Lmax2，以及，建模图像中亮度的平均值Lavg2构建。所述亮度补偿因子模型的构建过程为步骤S4031-S4035：
步骤S4031，选取n组建模图像，每组建模图像的Lmax2相等，所述Lmax2为建模图像中亮度的最大值；
举例说明，选取n组建模图像，其中建模图像的亮度值范围为0-255；相应的建模图像中亮度的最大值的范围为0-255，建模图像中亮度的平均值的范围为0-255。
优选的，选取的n组建模图像中亮度的最大值均匀分布于0-255的区间内；具体的，如果选取11组建模图像，每组建模图像中亮度的最大值Lmax2分别为：1、25、51、76、102、127、153、178、204、229、255。
步骤S4032，对于任意一组建模图像，分别计算每个建模图像的Lavg2，生成Lavg2集合，所述Lavg2为建模图像中亮度的平均值；
以Lmax2＝25为例，Lmax2＝25，相应的建模图像的Lavg2可以为：25、24、23、22、21、20、19、18、17、16、15、13、14、12、11、10、9、8、7、6、5、4、3、2、1、0中的任意一个数值。
Lmax2＝25组中的全部建模图像的Lavg2构成Lavg2集合。
步骤S4033，根据Lmax2＝25组和Lavg2集合，计算y集合，所述y为亮度补偿因子；
对于Lmax2＝25组，每个Lmax2＝25与一个Lavg2计算出一个y；多组Lmax2＝25与多个Lavg2得到一个y集合。
步骤S4034，根据Lmax2＝25组，Lavg2集合，以及，y集合，建立y＝f(Lavg2,Lmax2)关系曲线；
对于Lmax2＝25组，y＝f(Lavg2,Lmax2)的关系曲线如图16所示。
步骤S4035，n条所述关系曲线构建为亮度补偿因子模型。
为了达到增加显示图像的对比度，本申请实施例判断显示画面对比度，所述对比度基于显示画面的像素亮度值生成，根据对比度确定整幅显示画面亮度补偿因子，一般的对比度较大的场景尽量需要进一步加大对比度，因此可以对显示画面的低灰阶进行适当压低处理，对高灰阶进行适当抬高处理，对于对比度较小的场景尽量保持原有特性。
具体的实现过程，本申请实施例提供一种计算每组内每个建模图像中亮度的平均值的计算方法。具体的，统计建模图像各像素点的亮度值，生成第一亮度值集合；遍历第一亮度值集合，删除小于预置亮度值的亮度值，生成第二亮度值集合；计算所述第二亮度值集合的平均亮度值即为建模图像中亮度的平均值。
举例说明，预置亮度值为10，在显示图像平均亮度值计算过程中删除亮度值小于10的像素点。例如：10个像素点中，3个像素点的亮度小于10，平均亮度值的计算方式为用剩余7个像素点的亮度加和后的数值除10得到的结果即为建模图像中亮度的平均值。
最终构建的11条y＝f(Lavg2,Lmax2＝n)关系曲线，具体的请参阅图17；其中，y轴对应的数值为亮度补偿因子，x轴对应的数值为Lavg2，上述11条关系曲线构成亮度补偿因子模型。
所述将Lmax1和Lavg1代入亮度补偿因子模型，计算亮度补偿因子的步骤包括步骤S4036～S4037：
步骤S4036，对于亮度补偿因子模型，如果存在Lmax1＝Lmax2的关系曲线， 则根据Lavg1与亮度补偿因子之间的对应关系，得到亮度补偿因子；
举例说明，显示图像的Lmax1＝25，Lavg1＝13，在图18示出的亮度补偿因子模型中存在一条关系曲线，Lmax1＝Lmax2。在Lmax2＝25的关系曲线中，找到Lavg2＝13对应的亮度补偿因子，即为显示图像的亮度补偿因子。
步骤S4037，对于亮度补偿因子模型，如果不存在Lmax1＝Lmax2的关系曲线，则通过如下步骤S40371-S40372，计算亮度补偿因子：
步骤S40371，计算(Lmax1，Lavg1)的标定点index0，index1，index2，index3，以及，标定点对应的权重系数weight0，weight1，weight2，weight3；
步骤S40372，遍历亮度补偿因子模型，确定index0，index1，index2，index3对应的亮度补偿因子date0，date1，date2，date3；
步骤S40373，根据
Figure PCTCN2020081251-appb-000003
求得亮度补偿因子。
标定点，权重系数的计算过程如下：
step_h；
index_x＝(Lavg×step_h)>>14；
m 0＝(step_h×Lavg)&0x3fff；
m 1＝(1<<14)-m 0；
step_v；
index_y＝(Lmax×step_v)>>14；
n 0＝(step_v×Lmax)&0x3fff；
n 1＝(1<<14)-n 0；
index0＝index_y×N+index_x；
index1＝index_y×N+(index_x+1)；
index2＝(index_y+1)×N+index_x；
index3＝(index_y+1)×N+(index_x+1)；
weight0＝(m 1×n 1)>>12；
weight1＝(m 0×n 1)>>12；
weight2＝(m 1×n 0)>>12；
weight3＝(m 0×n 0)>>12.
其中，step_h为平均值方向取值步长，step_v为最大值方向取值步长，N为关系曲线的条数。
举例说明：
对于任意一幅显示图像，若计算出Lavg1为30，Lmax1为60，该显示图像的亮度的平均值和亮度的最大值组成一个点(30，60)。
如果建模图像以Lavg2和Lmax2建立表项，具体的请参阅图18。其中，表项是以Lavg2为横坐标以Lmax2为纵坐标进行建立。
请继续参阅图18，(30，60)的标定点为的确定过程为：确定表项中与30临近的两个Lavg2数值即25、51；表项中与60临近的两个Lmax2数值51、76，组成的四个标定点：index0、index1、index2、index3。
具体的计算过程：设
step_h＝160；
Index_x＝(30×160)>>14；
m 0＝(160×30)&0x3fff；
m 1＝(1<<14)-m 0；
step_v＝160；
Index_y＝(60×160)>>14；
n 0＝(160×60)&0x3fff
n 1＝(1<<14)-n 0
index0＝index_y×11+index_x；
index1＝index_y×11+(index_x+1)；
index2＝(index_y+1)×11+index_x；
index3＝(index_y+1)×11+(index_x+1).
其中，index0为(25，51)；index1为(51，51)；index2为(25，76)；index3为(51，76)；通过在图18示出的亮度补偿因子模型中确定，(25，51)， (51，51)，(25，76)，(51，76)四个标定点对应的亮度补偿因子，data_0、data_1、data_2、data_3。其中，四个标定点对应的权重系数分别为：
weight_0＝(m 1×n 1)>>12；
weight_1＝(m 0×n 1)>>12；
weight_2＝(m 1×n 0)>>12；
weight_3＝(m 0×n 0)>>12；
Figure PCTCN2020081251-appb-000004
S404，根据所述亮度补偿因子计算出每帧显示图像对应的亮度驱动信号。
可选择的，所述根据亮度补偿因子计算出每帧显示图像对应的亮度驱动信号的步骤包括：
依据亮度补偿因子对每帧显示图像对应的亮度进行补偿，得到每帧显示图像对应的亮度驱动信号；
判断所述亮度驱动信号是否大于或等于显示装置亮度的最大值；
设M为显示装置的亮度的最大值，如8bit通道的显示装置，包含了256个亮度，其中亮度的最大值为255，则M为255。如10bit通道的显示装置，包括1024个亮度，其中最大的亮度值为1023，则M为1023。
所述亮度驱动信号为显示装置亮度的最大值；增强处理后亮度值可能超出范围，需要限定在数据范围内，一般的如果是8bit数据，如果当前亮度值乘以各自的y(亮度补偿因子)后的亮度值大于255，则令输出的亮度值为255。
如果小于255，所述亮度驱动信号根据所述亮度补偿因子计算得出。本申请实施例第二方面示出一种亮度驱动方法，应用于双面板显示装置的第一面板，请参阅图19，所述方法包括步骤S601-S605：
S601，确定显示图像的亮度值集合，其中，所述亮度值集合包括所述显示图像各像素点的亮度值；
S602，将所述像素点亮度集合划分为预置数量个区域，生成区域亮度值集合，其中，每个区域包括至少一个像素点亮度值；
举例说明，4个点的数据下采样为一个点的数据，即将3840*2180个所述像素点划分为1920*1080个小区域，每个区域如图20所示。
S603，分别确定所述区域亮度值集合中每个区域亮度值的最大值和平均值；
其中，所述区域亮度的计算方法包括步骤S6031～S6032：
S6031，计算区域内Py-sum，以及，Py-avg，确定区域内Py-max，Py-mid，其中，Py-sum为像素点亮度和，Py-max为像素点亮度最大值，Py-avg为像素点亮度平均值，Py-mid为像素点亮度中间值。
Py-max和Py-mid的确定方法为：将Y1、Y2、Y3、Y4按照升序排列或按照降序排列，确定Py-max，对于4个亮度数据的中间值Py-mid，中间值可取中间两个亮度数据的平均值，或取中间两个亮度数据的任意一个亮度数据。
S6032，根据index 亮度＝(a×Py-max+b×Py-avg+c×Py-mid+512)>>10，计算index 亮度，所述index 亮度为区域亮度；
其中，a、b、c可以任意配置，但是必须满足a+b+c＝1024，且a、b、c均为正整数。
在一实施例中，本申请实施例示出了一种Py-mid位移取值方法，所述方法避免了将像素点亮度排序的过程，降低了处理器的数据处理量，提高了整体的运算速率。
具体的运算过程包括步骤S60321-S60323：
步骤S60321，计算区域内Py-sum，以及，Py-avg，确定区域内的Py-max，Py-min，其中，Py-sum为像素点亮度和，Py-max为像素点亮度最大值，Py-avg为像素点亮度平均值，Py-min为像素点亮度最小值；
步骤S60322，根据Py-mid＝(Py-sum–Py-max–Py-min+1)>>1，计算Py-mid，所述Py-mid为像素亮度中间值；
步骤S60323，最终根据index 亮度＝(a×Py-max+b×Py-avg+c×Py-mid+512)>>10，计算index 亮度，所述index 亮度为区域亮度；
其中，a、b、c可以任意配置，但是必须满足a+b+c＝1024，a、b、c均为正 整数。
将显示图像的3840*2180个像素亮度结合转化为1920*1080个区域亮度；1920*1080个区域亮度构成了区域亮度集合，相应的显示画面的亮度为1920*1080个区域亮度的集合。
本申请实施例对1920*1080个区域亮度进行标定，具体的，即区域亮度集合的每一个值或者某些值需要达到目标值(仪器测量值)，将到达目标值的亮度数据填写到区域亮度集合中，如果显示图像要做到精准，每一个区域亮度均需要标定。
工程实现一般采用标定某些固定采样点，(等间距或者不等间距)确定采样点后，其他亮度值通过插值方法或者数据拟合的方法得到。
也可以用采样固定曲线的方法，例如y＝x，y＝x γ，γ＝2.2、2.3、0.45等，可以根据显示面板的特性以及最终想要表现特性来确定。
S604，根据每个区域亮度值的最大值和平均值计算区域亮度补偿因子；
本申请实施例示出的亮度补偿因子可以为整体亮度补偿因子，也可以为区域亮度补偿因子。相应的，对应的补偿方法为整体增亮法，或区域增亮法。
(1)整体增亮法的亮度补偿因子的计算方式：
计算出显示图像中亮度的最大值Lmax1，此最大值不是所有亮度值最大的一个，而是统计意义下的最大值，一般是统计结束后，从255灰阶到0灰阶查找到像素个数不为零的那一阶且每个灰阶包含的像素的个数需要超过某个阈值(例如总个数的0.1％),如果该阶像素的个数不满足要求，则将该灰阶像素的个数累加到下一阶像素的个数，直到找到满足条件的那一阶像素的个数停止；此灰阶即为最大值；显示图像中亮度的平均值Lavg1的计算，如果将一幅显示图像的像素点的亮度值全部累加后再除以像素点的个数，累加和的数据位宽一般会溢出，特别当数据位宽为10bit和12bit时，为了便于计算，可以先计算每一行的亮度均值，再计算出n个行的亮度均值，然后对n个行的亮度均值进行求取平均值，得到整幅显示图像的亮度的平均值。
将Lmax1和Lavg1代入亮度补偿因子模型，计算亮度补偿因子。所述亮度补偿因子模型的构建方式与前述实施例中亮度补偿因子模型的构建方式相同，详见前述实施例。
分别对区域亮度index 亮度的数据进行增强处理，增强处理后的亮度数据可能超出范围，需要限定在数据范围内，一般的，对于8bit数据，如果亮度数据乘以各自的y(亮度补偿因子)后的数据大于255，输出的亮度数据为255。
(2)区域增亮法的亮度补偿因子的计算方式：
分别计算每个区域内的区域亮度补偿因子。
在本申请实施例中，将显示图像的3840*2180个像素转化为1920*1080个区域，为了提高本申请实施例调节的准确性，本申请实施例分别计算出每个区域对应的亮度补偿因子，具体的：
首先，计算出每个区域亮度的平均值Lavg3，以及，该区域的亮度的最大值Lmax3；
将Lmax3和Lavg3代入亮度补偿因子模型，计算区域亮度补偿因子。
S605，根据所述区域亮度补偿因子和区域亮度值，计算出每个区域对应的亮度驱动信号。
对区域亮度进行增强处理，具体的亮度驱动信号的计算方法为每个区域亮度*亮度补偿因子。
本申请实施例示出的亮度补偿因子可以为整体亮度补偿因子，也可以为区域亮度补偿因子。相应的，对应的补偿方法为整体增亮法，或区域增亮法。
其中，所述根据区域亮度补偿因子和区域亮度，计算出每个区域对应的亮度驱动信号的步骤包括：
依据区域亮度补偿因子对每个区域对应的区域亮度进行补偿，得到每个区域对应的亮度驱动信号；
判断所述亮度驱动信号是否大于或等于显示装置亮度的最大值；
如果大于或等于，所述亮度驱动信号为显示装置亮度的最大值；
如果小于，所述亮度驱动信号根据所述区域亮度补偿因子和区域亮度计算得出。
增强处理后的亮度数据可能超出范围，需要限定在数据范围内，一般的，对于8bit数据，如果亮度数据乘以各自的y后的数据大于255，输出的亮度数据为255。
本领域技术人员在考虑说明书及实践这里公开的公开后，将容易想到本公开的其它实施方案。本申请旨在涵盖本公开的任何变型、用途或者适应性变化，这些变型、用途或者适应性变化遵循本公开的一般性原理并包括本公开未公开的本技术领域中的公知常识或惯用技术手段。说明书和实施例仅被视为示例性的，本公开的范围和精神由下面的权利要求指出。
应当理解的是，本公开并不局限于上面已经描述并在附图中示出的精确结构，并且可以在不脱离其范围进行各种修改和改变。本公开的范围仅由所附的权利要求来限制。

Claims (18)

  1. 一种用于双面板显示装置的对比度提升算法，包括：
    接收显示图像各第二像素点的RGB值，根据所述各第二像素点的RGB值，确定各第一像素点的亮度值，其中，所述第二像素点是位于所述双面板显示装置的第二面板的像素，所述第一像素点是位于所述双面板显示装置的第一面板的像素，所述第一面板位于发光源和所述第二面板之间；
    根据各第一像素点的亮度值，进行局部区域亮度值统计和全局图像亮度值统计，确定局部亮度调整因子和全局亮度调整因子；
    根据各第一像素点的亮度值、局部亮度调整因子和全局亮度调整因子，计算对应第一像素点的亮度驱动信号，其中，所述亮度驱动信号用于调整第一面板对应像素点的透光率，全局亮度调整因子用于调整第一面板对应像素点的输出亮度值。
  2. 根据权利要求1所述的对比度提升算法，所述根据各第一像素点的亮度值、局部亮度调整因子和全局亮度调整因子，计算对应第一像素点的亮度驱动信号的步骤包括：
    根据局部亮度调整因子，对第一像素点的亮度值拉伸调整，生成局部亮度调整值，根据全局亮度调整因子，对第一像素点的亮度值拉伸调整，生成全局亮度调整值；
    根据所述局部亮度调整值和全局亮度调整值，计算对应第一像素点的亮度驱动信号。
  3. 根据权利要求2所述的对比度提升算法，所述全局亮度调整因子包括：全局亮度上调因子和全局亮度下调因子，所述根据全局亮度调整因子，对第一像素点的亮度值拉伸调整，生成全局亮度调整值的步骤包括：
    根据各第一像素点的亮度值，计算显示图像的亮度平均值；
    对于复数个第一像素点中的一个第一像素点，如果所述第一像素点的亮度 值小于显示图像的亮度平均值，根据所述全局亮度下调因子，下调所述第一像素点的亮度值，生成全局亮度调整值；
    如果所述第一像素点的亮度值大于显示图像的亮度平均值，根据所述全局亮度上调因子，上调所述第一像素点的亮度值，生成全局亮度调整值。
  4. 根据权利要求2所述的对比度提升算法，所述局部亮度调整因子包括：局部亮度上调因子和局部亮度下调因子，所述根据局部亮度调整因子，对第一像素点的亮度值拉伸调整，生成局部亮度调整值的步骤包括：
    对于任意第一像素点，以该第一像素点位置为中心m*n个像素块，构成局部区域，局部区域的亮度值包括：所述m*n个像素的亮度值；
    根据局部区域的亮度值，计算局部区域的亮度平均值；
    如果第一像素点的亮度值小于局部区域的亮度平均值，则根据局部亮度下调因子，下调所述第一像素点的亮度值，生成局部亮度调整值；
    如果所述第一像素点的亮度值大于局部区域的亮度平均值，根据局部亮度上调因子，上调所述第一像素点的亮度值，生成局部亮度调整值。
  5. 根据权利要求4所述的对比度提升算法，根据所述局部亮度调整值和全局亮度调整值，计算对应第一像素点的亮度驱动信号的步骤包括：
    根据第一像素点对应的局部区域亮度值，计算局部亮度权重系数；
    根据局部亮度调整值，以及，局部亮度权重系数，计算局部亮度输出值，根据全局亮度调整值，以及，全局亮度权重系数，计算全局亮度输出值，其中，所述局部亮度权重系数与所述全局亮度权重系数的和为1；
    根据所述局部亮度输出值，以及，全局亮度输出值，计算对应第一像素点的亮度驱动信号。
  6. 根据权利要求5所述的对比度提升算法，所述局部亮度权重系数的计算包括：
    选取N个局部建模区域，所述局部建模区域包括：第一建模像素点的建模亮度值，以及，第一建模像素点邻域的邻域像素亮度值，以及，第一建模像素 点对应的局部建模亮度权重系数；
    根据建模亮度值，以及，邻域像素亮度值，计算第一建模像素点的建模亮度复杂度；
    根据所述建模亮度复杂度与局部建模亮度权重系数，构建第一局部亮度权重系数曲线；
    对于复数个第一像素点中的任意一个，根据第一像素点对应的局部区域亮度值，计算所述第一像素点的复杂度，根据所述第一像素点的复杂度，以及，第一局部亮度权重系数曲线，计算所述第一建模像素点对应的局部亮度权重系数。
  7. 根据权利要求5所述的对比度提升算法，所述局部亮度权重系数的计算包括：
    选取N个局部建模区域，所述局部建模区域包括：局部建模区域的亮度值，以及，第二建模像素点对应的局部建模亮度权重系数，所述局部建模区域的亮度值包括：第二建模像素点的建模亮度值，以及，第二建模像素点邻域的邻域像素亮度值；
    统计局部建模区域中各亮度值出现的建模频数，生成第一建模频数集合；
    遍历第一建模频数集合，删除小于预置频数的第一建模频数，生成第二建模频数集合；
    统计第二建模频数集合中包含的亮度值的建模数量，根据所述建模数量与局部建模亮度权重系数，构建第二局部亮度权重系数曲线；
    对于复数个第一像素点中的任意一个第一，统计第一像素点对应的局部区域亮度值中频数大于预置频数的亮度值的数量，根据所述数量，以及，第二局部亮度权重系数曲线，计算所述第一像素点对应的局部亮度权重系数。
  8. 根据权利要求5所述的对比度提升算法，所述局部亮度权重系数的计算包括：
    选取N个局部建模区域，所述局部建模区域包括：第三建模像素点的建模 亮度值，与第三建模像素点接壤的第三建模像素点的接壤亮度值，以及，第三建模像素点对应的局部建模亮度权重系数；
    根据所述建模亮度值和所述接壤亮度值，计算第三建模像素点的建模亮度特征；
    根据所述建模亮度特征与局部建模亮度权重系数构建第三局部亮度权重系数曲线；
    对于复数个第一像素点中的一个第一像素点，计算所述第一像素点的亮度特征，根据所述第一像素点的亮度特征，以及，第三局部亮度权重系数曲线，计算所述第一像素点对应的局部亮度权重系数。
  9. 根据权利要求1所述的对比度提升算法，所述方法还包括：
    根据复数个第二像素点的RGB值，进行局部区域的RGB值统计，确定局部彩色调整因子；根据第二面板的全局的第二像素点的RGB值，以及，第二面板的全局图像亮度值统计，确定全局彩色调整因子；
    根据各第二像素点的RGB值、局部彩色调整因子和全局彩色调整因子，计算对应第二像素点的彩色驱动信号，所述彩色驱动信号用于调整第二面板对应所述第二像素点的RGB值。
  10. 一种双面板显示装置，包括：
    处理器，
    第一面板，与所述处理器相连接并且配置为接收亮度驱动信号，根据亮度驱动信号调整对应第一像素点的透光率，以及
    第二面板，与所述处理器相连接并且配置为接收彩色驱动信号，根据彩色驱动信号调整对应第二像素点的RGB值；
    所述处理器，配置为执行：
    接收显示图像各第二像素点的RGB值，根据所述各第二像素点的RGB值，确定各第一像素点的亮度值，其中，所述第二像素点是位于所述双面板显示装置的第二面板的像素，所述第一像素点是位于所述双面板显示装置的第一面板 的像素，所述第一面板位于发光源和所述第二面板之间；
    根据各第一像素点的亮度值，进行局部区域亮度值统计和全局图像亮度值统计，确定局部亮度调整因子和全局亮度调整因子；
    根据各第一像素点的亮度值、局部亮度调整因子和全局亮度调整因子，计算对应第一像素点的亮度驱动信号，其中，所述亮度驱动信号用于调整第一面板对应像素点的透光率，全局亮度调整因子用于调整第一面板对应像素点的输出亮度值。
  11. 根据权利要求10所述的双面板显示装置，所述处理器进一步配置为通过下述执行所述根据各第一像素点的亮度值、局部亮度调整因子和全局亮度调整因子，计算对应第一像素点的亮度驱动信号：
    根据局部亮度调整因子，对第一像素点的亮度值拉伸调整，生成局部亮度调整值，根据全局亮度调整因子，对第一像素点的亮度值拉伸调整，生成全局亮度调整值；
    根据所述局部亮度调整值和全局亮度调整值，计算对应第一像素点的亮度驱动信号。
  12. 根据权利要求11所述的双面板显示装置，所述全局亮度调整因子包括：全局亮度上调因子和全局亮度下调因子，
    所述处理器进一步配置为通过下述执行根据全局亮度调整因子，对第一像素点的亮度值拉伸调整，生成全局亮度调整值：
    根据各第一像素点的亮度值，计算显示图像的亮度平均值；
    对于复数个第一像素点中的一个第一像素点，如果所述第一像素点的亮度值小于显示图像的亮度平均值，根据所述全局亮度下调因子，下调所述第一像素点的亮度值，生成全局亮度调整值；
    如果所述第一像素点的亮度值大于显示图像的亮度平均值，根据所述全局亮度上调因子，上调所述第一像素点的亮度值，生成全局亮度调整值。
  13. 根据权利要求11所述的双面板显示装置，所述局部亮度调整因子包括： 局部亮度上调因子和局部亮度下调因子，所述处理器进一步配置为通过下述执行根据局部亮度调整因子，对第一像素点的亮度值拉伸调整，生成局部亮度调整值：
    对于任意第一像素点，以该第一像素点位置为中心m*n个像素块，构成局部区域，局部区域的亮度值包括：所述m*n个像素的亮度值；
    根据局部区域的亮度值，计算局部区域的亮度平均值；
    如果第一像素点的亮度值小于局部区域的亮度平均值，则根据局部亮度下调因子，下调所述第一像素点的亮度值，生成局部亮度调整值；
    如果所述第一像素点的亮度值大于局部区域的亮度平均值，根据局部亮度上调因子，上调所述第一像素点的亮度值，生成局部亮度调整值。
  14. 根据权利要求13所述的双面板显示装置，所述处理器进一步配置为通过下述执行根据所述局部亮度调整值和全局亮度调整值，计算对应第一像素点的亮度驱动信号：
    根据第一像素点对应的局部区域亮度值，计算局部亮度权重系数；
    根据局部亮度调整值，以及，局部亮度权重系数，计算局部亮度输出值，根据全局亮度调整值，以及，全局亮度权重系数，计算全局亮度输出值，其中，所述局部亮度权重系数与所述全局亮度权重系数的和为1；
    根据所述局部亮度输出值，以及，全局亮度输出值，计算对应第一像素点的亮度驱动信号。
  15. 根据权利要求13所述的双面板显示装置，所述处理器进一步配置为通过下述执行所述局部亮度权重系数的计算：
    选取N个局部建模区域，所述局部建模区域包括：第一建模像素点的建模亮度值，以及，第一建模像素点邻域的邻域像素亮度值，以及，第一建模像素点对应的局部建模亮度权重系数；
    根据建模亮度值，以及，邻域像素亮度值，计算第一建模像素点的建模亮度复杂度；
    根据所述建模亮度复杂度与局部建模亮度权重系数，构建第一局部亮度权重系数曲线；
    对于复数个第一像素点中的任意一个，根据第一像素点对应的局部区域亮度值，计算所述第一像素点的复杂度，根据所述第一像素点的复杂度，以及，第一局部亮度权重系数曲线，计算所述第一建模像素点对应的局部亮度权重系数。
  16. 根据权利要求14所述的双面板显示装置，所述处理器进一步配置为通过下述执行局部亮度权重系数的计算：
    选取N个局部建模区域，所述局部建模区域包括：局部建模区域的亮度值，以及，第二建模像素点对应的局部建模亮度权重系数，所述局部建模区域的亮度值包括：第二建模像素点的建模亮度值，以及，第二建模像素点邻域的邻域像素亮度值；
    统计局部建模区域中各亮度值出现的建模频数，生成第一建模频数集合；
    遍历第一建模频数集合，删除小于预置频数的第一建模频数，生成第二建模频数集合；
    统计第二建模频数集合中包含的亮度值的建模数量，根据所述建模数量与局部建模亮度权重系数，构建第二局部亮度权重系数曲线；
    对于复数个第一像素点中的任意一个第一，统计第一像素点对应的局部区域亮度值中频数大于预置频数的亮度值的数量，根据所述数量，以及，第二局部亮度权重系数曲线，计算所述第一像素点对应的局部亮度权重系数。
  17. 根据权利要求14所述的双面板显示装置，所述处理器进一步配置为通过下述执行局部亮度权重系数的计算：
    选取N个局部建模区域，所述局部建模区域包括：第三建模像素点的建模亮度值，与第三建模像素点接壤的第三建模像素点的接壤亮度值，以及，第三建模像素点对应的局部建模亮度权重系数；
    根据所述建模亮度值和所述接壤亮度值，计算第三建模像素点的建模亮度 特征；
    根据所述建模亮度特征与局部建模亮度权重系数构建第三局部亮度权重系数曲线；
    对于复数个第一像素点中的一个第一像素点，计算所述第一像素点的亮度特征，根据所述第一像素点的亮度特征，以及，第三局部亮度权重系数曲线，计算所述第一像素点对应的局部亮度权重系数。
  18. 根据权利要求10所述的双面板显示装置，所述处理器进一步配置为：
    根据复数个第二像素点的RGB值，进行局部区域的RGB值统计，确定局部彩色调整因子；
    根据第二面板的全局的第二像素点的RGB值，以及，第二面板的全局图像亮度值统计，确定全局彩色调整因子；
    根据各第二像素点的RGB值、局部彩色调整因子和全局彩色调整因子，计算对应第二像素点的彩色驱动信号，所述彩色驱动信号用于调整第二面板对应所述第二像素点的RGB值。
PCT/CN2020/081251 2019-04-04 2020-03-25 一种对比度提升算法及双面板显示装置 WO2020200015A1 (zh)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US16/847,942 US11263987B2 (en) 2019-04-04 2020-04-14 Method of enhancing contrast and a dual-cell display apparatus

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN201910272176.5 2019-04-04
CN201910272176.5A CN111785222B (zh) 2019-04-04 2019-04-04 一种对比度提升算法及双面板显示装置

Related Child Applications (1)

Application Number Title Priority Date Filing Date
US16/847,942 Continuation US11263987B2 (en) 2019-04-04 2020-04-14 Method of enhancing contrast and a dual-cell display apparatus

Publications (1)

Publication Number Publication Date
WO2020200015A1 true WO2020200015A1 (zh) 2020-10-08

Family

ID=72664559

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2020/081251 WO2020200015A1 (zh) 2019-04-04 2020-03-25 一种对比度提升算法及双面板显示装置

Country Status (2)

Country Link
CN (1) CN111785222B (zh)
WO (1) WO2020200015A1 (zh)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2023102777A1 (zh) * 2021-12-08 2023-06-15 京东方科技集团股份有限公司 显示面板及显示装置

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114613340B (zh) * 2022-03-17 2023-08-08 北京京东方显示技术有限公司 显示面板、显示模组及系统、显示驱动方法及装置
WO2023240624A1 (zh) * 2022-06-17 2023-12-21 北京小米移动软件有限公司 亮度调整方法及装置、存储介质

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103502881A (zh) * 2011-04-28 2014-01-08 杜比实验室特许公司 具有用于补偿变化的消色差lcd面板驱动状况的颜色校正的双lcd显示器
CN105047145A (zh) * 2015-09-14 2015-11-11 青岛海信电器股份有限公司 背光亮度控制方法、背光亮度控制装置及显示终端
CN107450203A (zh) * 2016-05-31 2017-12-08 乐金显示有限公司 光阀面板以及使用其的液晶显示器
CN108020956A (zh) * 2016-11-02 2018-05-11 群创光电股份有限公司 显示装置
US20180286326A1 (en) * 2017-03-31 2018-10-04 Panasonic Liquid Crystal Display Co., Ltd. Liquid crystal display device and a method for driving thereof with a first and second lcd panel

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH02198489A (ja) * 1989-01-27 1990-08-06 Toshiba Corp 情報板表示装置
JPH02309315A (ja) * 1989-05-25 1990-12-25 Stanley Electric Co Ltd カラー表示装置
JPH08220514A (ja) * 1995-02-13 1996-08-30 Asahi Glass Co Ltd 液晶表示装置
JP2005164677A (ja) * 2003-11-28 2005-06-23 Chi Mei Electronics Corp 画像表示装置
CN107342058B (zh) * 2017-08-30 2020-04-14 创维液晶器件(深圳)有限公司 液晶显示模组亮度调节方法、测试板、系统和设备
CN107644409B (zh) * 2017-09-28 2022-01-04 深圳Tcl新技术有限公司 图像增强方法、显示装置及计算机可读存储介质
CN107730475B (zh) * 2017-11-13 2019-08-23 苏州科达科技股份有限公司 图像增强方法及系统
CN108831357A (zh) * 2018-05-02 2018-11-16 广州市统云网络科技有限公司 一种led显示屏工作状况自动监测与控制方法

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103502881A (zh) * 2011-04-28 2014-01-08 杜比实验室特许公司 具有用于补偿变化的消色差lcd面板驱动状况的颜色校正的双lcd显示器
CN105047145A (zh) * 2015-09-14 2015-11-11 青岛海信电器股份有限公司 背光亮度控制方法、背光亮度控制装置及显示终端
CN107450203A (zh) * 2016-05-31 2017-12-08 乐金显示有限公司 光阀面板以及使用其的液晶显示器
CN108020956A (zh) * 2016-11-02 2018-05-11 群创光电股份有限公司 显示装置
US20180286326A1 (en) * 2017-03-31 2018-10-04 Panasonic Liquid Crystal Display Co., Ltd. Liquid crystal display device and a method for driving thereof with a first and second lcd panel

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2023102777A1 (zh) * 2021-12-08 2023-06-15 京东方科技集团股份有限公司 显示面板及显示装置

Also Published As

Publication number Publication date
CN111785222A (zh) 2020-10-16
CN111785222B (zh) 2021-05-28

Similar Documents

Publication Publication Date Title
US11263987B2 (en) Method of enhancing contrast and a dual-cell display apparatus
US20200111401A1 (en) Method and device for driving display panel, and display apparatus
CN107529049B (zh) 显示装置图像处理方法、图像处理系统及显示装置
CN101593508B (zh) 基于直方图的动态背光控制系统和方法
TWI330270B (en) Region-based displayer and display method thereof
JP4149699B2 (ja) 時分割方式液晶表示装置及びそのカラー映像表示方法
WO2020200015A1 (zh) 一种对比度提升算法及双面板显示装置
CN104981861B (zh) 信号转换装置和方法
CN101593509B (zh) 输入伽玛抖动系统及方法
CN111785224B (zh) 一种亮度驱动方法
US8681190B2 (en) Liquid crystal display
JP5124051B1 (ja) 表示装置
CN101593507B (zh) 后色彩空间转换处理系统及方法
CN107103886B (zh) 一种动态背光控制显示方法及装置
CN105448245A (zh) 背光亮度补偿方法及显示装置
US10347198B2 (en) Image displaying methods and display devices
US10629139B2 (en) Backlight module and control method of display device
US20120001951A1 (en) Liquid crystal display
CN103325351A (zh) 图像处理装置和图像处理方法
US20180182344A1 (en) Display driving circuit and liquid crystal display (lcd) panel thereof
WO2020019431A1 (zh) 一种四场时序液晶显示控制方法
US10923079B2 (en) Dual-cell display apparatus
US11308895B2 (en) Liquid crystal display device, image displaying method thereof, and backlight control device for local dimming
TW202143214A (zh) 顯示器驅動裝置及驅動方法
US20210056919A1 (en) Method and device for controlling brightness of display device, and liquid crystal display

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 20782940

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 20782940

Country of ref document: EP

Kind code of ref document: A1