Display device and color conversion method

Abstract

The embodiment of the application belongs to display technology, and provides a display device and a color conversion method. The method comprises the following steps: acquiring a duty cycle of a backlight partition in a display device; determining a dynamic color gamut vertex of the backlight partition based on the duty cycle of the backlight partition and a color gamut range of the display device under the backlight partition, and determining a dynamic color gamut matrix corresponding to the backlight partition according to the dynamic color gamut vertex; and performing color conversion on an input image signal of the backlight partition based on the dynamic color gamut matrix corresponding to the backlight partition. According to the scheme of the application, when the input image signal in the backlight partition causes the duty cycle to change, the dynamic color gamut vertex and the dynamic color gamut matrix can change synchronously, and the dynamic color gamut matrices corresponding to at least two backlight partitions are different, so that more refined color management can be realized for different backlight states of each backlight partition, colorimetric coordinate deviation caused by a fixed color gamut matrix is reduced, and the accuracy of color display is improved.

Description

TECHNICAL FIELD

[0001] Embodiments of the present application relate to display technology. More specifically, they relate to a display device and a color conversion method. BACKGROUND

[0002] RGB backlight technology can mix a wider and purer color than traditional white backlight by independently controlling red, green and blue primary color lamps. On this basis, the LD area light control technology (Local Dimming) divides the backlight into multiple independent partitions, and the brightness of each partition can be adjusted according to the local content of the current display image to achieve a higher dynamic range.

[0003] In related technologies, the RGB duty cycle of different backlight partitions changes dynamically, and the traditional fixed color gamut conversion matrix cannot match the dynamic color gamut requirement, resulting in a shift of chromaticity coordinates, thereby causing color difference and color distortion between partitions. Therefore, the current problem to be solved is how to improve the accuracy of color display. SUMMARY

[0004] Embodiments of the present application provide a display device and a color conversion method, which can improve the accuracy of color display.

[0005] In a first aspect, embodiments of the present application provide a display device, which comprises: a controller configured to: obtain a duty cycle of a backlight partition in the display device; wherein the duty cycle is determined based on an input image signal of the backlight partition; determine a dynamic color gamut vertex of the backlight partition based on the duty cycle of the backlight partition and a color gamut range of the display device under the backlight partition, and determine a dynamic color gamut matrix corresponding to the backlight partition according to the dynamic color gamut vertex; perform color conversion on the input image signal of the backlight partition based on the dynamic color gamut matrix corresponding to the backlight partition; wherein the dynamic color gamut matrices corresponding to at least two backlight partitions are different; a backlight module connected with the controller, the backlight module comprising a plurality of backlight light sources configured to control the backlight light sources to emit light according to the duty cycles of the plurality of backlight partitions; the backlight light sources comprising at least two types of light emitting chips emitting light rays of different wavelengths; and a display panel connected with the controller and configured to display the color-converted image signal.

[0006] The technical solution related to the above embodiments has the following advantages or beneficial effects: in the present example, when the input image signal in the backlight partition causes the duty cycle to change, the dynamic color gamut vertex and the dynamic color gamut matrix can change synchronously, and the dynamic color gamut matrices corresponding to at least two backlight partitions are different, which can achieve more refined color management for different backlight states of each backlight partition, improve the local contrast and color saturation of the picture, and the calculation of the dynamic color gamut vertex takes into account the color gamut range of the hardware device, reducing the shift of chromaticity coordinates caused by the fixed color gamut matrix, thereby improving the accuracy of color display.

[0007] In some embodiments of the present application, the controller is configured to determine the red duty cycle, the green duty cycle and the blue duty cycle of the backlight partition according to the maximum red pixel value, the maximum green pixel value and the maximum blue pixel value in the backlight partition.

[0008] The technical solutions related in the above embodiments have the following advantages or beneficial effects: in the example, the determination of the duty cycle is refined from the overall brightness to the maximum pixel values corresponding to the red, green and blue primary colors, thereby achieving more refined control of the backlight, and thus helping to more accurately match the color intent of the input signal.

[0009] In some embodiments of the present application, the controller is configured to sum the product of the maximum red pixel value in the backlight partition and the first weight with the product of the average red pixel value in the backlight partition and the second weight, and take the sum as the red duty cycle; wherein the sum of the first weight and the second weight is 1; sum the product of the maximum green pixel value in the backlight partition and the first weight with the product of the average green pixel value in the backlight partition and the second weight, and take the sum as the green duty cycle; sum the product of the maximum blue pixel value in the backlight partition and the first weight with the product of the average blue pixel value in the backlight partition and the second weight, and take the sum as the blue duty cycle.

[0010] The technical solutions related in the above embodiments have the following advantages or beneficial effects: in the example, the duty cycles of each color are calculated by weighted sum of the maximum value and the average value, while taking into account the peak brightness requirement of the picture and the overall brightness basis, thereby improving the authenticity and balance of the color duty cycle.

[0011] In some embodiments of the present application, the controller is configured to calculate a red normalized value according to the red duty cycle, the total duty cycle and the difference expansion coefficient, and update the red duty cycle to the red normalized value; wherein the total duty cycle is determined according to the red duty cycle, the green duty cycle and the blue duty cycle; calculate a green normalized value according to the green duty cycle, the total duty cycle and the difference expansion coefficient, and update the green duty cycle to the green normalized value; calculate a blue normalized value according to the blue duty cycle, the total duty cycle and the difference expansion coefficient, and update the blue duty cycle to the blue normalized value.

[0012] The technical solutions related in the above embodiments have the following advantages or beneficial effects: in the example, based on the unified difference expansion coefficient, the duty cycles of red, green and blue are updated synchronously, and the difference in the duty cycle of each primary color relative to the total duty cycle can be enlarged or reduced evenly on the basis of the normalized processing of the duty cycle.

[0013] In some embodiments of the present application, the color gamut range of the display device under backlight partitioning includes an interval from a first color gamut to a second color gamut; the first color gamut is a color gamut defined by a red first coordinate, a green first coordinate and a blue first coordinate in a colorimetric diagram when the display device displays a color of a preset red, a preset green or a preset blue and a display brightness is a first brightness under backlight partitioning; the second color gamut is a color gamut defined by a red second coordinate, a green second coordinate and a blue second coordinate in the colorimetric diagram when the display device displays a white color and a display brightness is a second brightness under backlight partitioning; and the second brightness is less than the first brightness.

[0014] The technical solutions related in the above embodiments have the following advantages or beneficial effects: the scheme of the present example limits the color gamut range of the display device under backlight partitioning in an interval from a first color gamut to a second color gamut, quantifies the offset of the color gamut range of the display device with the change of brightness, and can improve the accuracy of subsequent calculation of a dynamic color gamut vertex, thereby providing more accurate boundary conditions for color conversion.

[0015] In some embodiments of the present application, the dynamic color gamut vertex includes a red vertex coordinate, a green vertex coordinate and a blue vertex coordinate; and the controller is configured to determine the red vertex coordinate according to a red duty ratio, the red first coordinate and the red second coordinate, determine the green vertex coordinate according to a green duty ratio, the green first coordinate and the green second coordinate, and determine the blue vertex coordinate according to a blue duty ratio, the blue first coordinate and the blue second coordinate.

[0016] The technical solutions related in the above embodiments have the following advantages or beneficial effects: the scheme of the present example determines the dynamic color gamut vertex by mapping the dynamic duty ratio of each color between the corresponding preset color gamut boundary coordinates, realizes continuous and adaptive adjustment of the color gamut range determined by the dynamic color gamut vertex with the change of backlight brightness, and thereby can improve the accuracy and color consistency of the color conversion reference.

[0017] In some embodiments of the present application, the controller is configured to obtain a target color gamut matrix, determine a source color gamut matrix according to the dynamic color gamut vertex, and calculate a dynamic color gamut matrix according to the source color gamut matrix and the target color gamut matrix; and the inverse of the dynamic color gamut matrix and an input image signal of the backlight partitioning are processed to complete color conversion.

[0018] The technical solutions related in the above embodiments have the following advantages or beneficial effects: the scheme of the present example calculates the conversion relationship by the dynamically generated source color gamut matrix (representing the actual color gamut under the current backlight) and the target color gamut matrix (representing the standard color gamut of the output signal), and can realize the mapping from the input image signal to the output image signal.

[0019] In some embodiments of the present application, the controller is configured to: calculate a white X value and a white Z value according to a primary color conversion algorithm based on the white vertex coordinates and a white Y value fixed as 1; wherein in the primary color conversion algorithm, the X value is determined based on the vertex coordinates and the Y value, and the Z value is determined based on the vertex coordinates and the Y value; determine an initial matrix based on the dynamic color gamut vertex, and determine a scaling coefficient according to the initial matrix and the white Y value, the white X value and the white Z value; and calculate the source color gamut matrix according to the scaling coefficient and the initial matrix.

[0020] The technical solutions related in the above embodiments have the following advantages or beneficial effects: in the example, the complete white point tristimulus values are calculated by the white vertex coordinates and the fixed Y value, and the scaling coefficient is further determined to construct the matrix, white point calibration is achieved, and thus the accuracy of the source color gamut matrix calculation is improved.

[0021] In some embodiments of the present application, the dynamic color gamut vertex includes red vertex coordinates, green vertex coordinates and blue vertex coordinates; the controller is configured to: calculate a red Y value according to a red duty ratio and a brightness coefficient, calculate a green Y value according to a green duty ratio and the brightness coefficient, and calculate a blue Y value according to a blue duty ratio and the brightness coefficient; calculate a red X value and a red Z value based on the red vertex coordinates and the red Y value, calculate a green X value and a green Z value based on the green vertex coordinates and the green Y value, and calculate a blue X value and a blue Z value based on the blue vertex coordinates and the blue Y value according to a primary color conversion algorithm, so as to construct an initial matrix.

[0022] The technical solutions related in the above embodiments have the following advantages or beneficial effects: in the example, the dynamic duty ratios of the primary colors are converted into the corresponding brightness components (Y values), and the initial matrix is constructed in combination with the chromaticity coordinates, so that the tristimulus values for the color gamut conversion can more accurately reflect the actual light energy distribution under the current backlight, and thus the coordination of the display colors is improved.

[0023] In a second aspect, the embodiments of the present application provide a color conversion method, including: obtaining a duty ratio of a backlight partition in a display device; wherein the duty ratio is determined based on an input image signal of the backlight partition; determining a dynamic color gamut vertex of the backlight partition based on the duty ratio of the backlight partition and a color gamut range of the display device under the backlight partition, and determining a dynamic color gamut matrix corresponding to the backlight partition according to the dynamic color gamut vertex; and performing color conversion on the input image signal of the backlight partition based on the dynamic color gamut matrix corresponding to the backlight partition; wherein the dynamic color gamut matrices corresponding to at least two backlight partitions are different.

[0024] The technical scheme related to the above embodiment has the following advantages or beneficial effects: in the scheme of the example, when the input image signal in the backlight partition causes the duty cycle to change, the dynamic color gamut vertex and the dynamic color gamut matrix can change synchronously, and the dynamic color gamut matrices corresponding to the at least two backlight partitions are different, so that more refined color management can be realized for different backlight states of each backlight partition, the local contrast and color saturation of the picture can be improved, the calculation of the dynamic color gamut vertex considers the color gamut range of the hardware device, the color coordinate offset caused by the fixed color gamut matrix is reduced, and the accuracy of color display is improved. BRIEF DESCRIPTION OF DRAWINGS

[0025] In order to more clearly illustrate the embodiments of the present application or the implementation manners in the related art, the drawings needed to be used in the embodiment or related art description will be briefly introduced. Obviously, the drawings in the following description are some embodiments of the present application, and other drawings can also be obtained by those skilled in the art according to these drawings.

[0026] Figure 1 The structural schematic diagram of the display device provided by the embodiment of the present application is shown in the figure.

[0027] Figure 2 The driving architecture schematic diagram of the display device provided by the embodiment of the present application is shown in the figure.

[0028] Figure 3 The color gamut contrast difference schematic diagram provided by the embodiment of the present application is shown in the figure.

[0029] Figure 4 The flowchart of the color conversion method provided by the embodiment of the present application is shown in the figure.

[0030] Figure 5 The flowchart of the color conversion method provided by the embodiment of the present application is shown in the figure.

[0031] Figure 6 The flowchart of the color conversion method provided by the embodiment of the present application is shown in the figure.

[0032] Figure 7 The flowchart of the color conversion method provided by the embodiment of the present application is shown in the figure.

[0033] Figure 8 The flowchart of the color conversion method provided by the embodiment of the present application is shown in the figure.

[0034] Figure 9 The flowchart of the color conversion method provided by the embodiment of the present application is shown in the figure.

[0035] Figure 10 The flowchart of the color conversion method provided by the embodiment of the present application is shown in the figure.

[0036] Figure 11 A structural schematic diagram of a color conversion device provided in the present application is shown. DETAILED DESCRIPTION

[0037] In order to make the objects, implementations and advantages of the present application clearer, the following will combine the accompanying drawings for the exemplary embodiments of the present application to make a clear and complete description of the exemplary embodiments of the present application. Obviously, the described exemplary embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application.

[0038] It should be noted that the brief description of the terms in the present application is only for the convenience of understanding the following described embodiments, and is not intended to limit the embodiments of the present application. Unless otherwise specified, these terms should be understood according to their ordinary and general meanings.

[0039] In addition, the terms “comprising” and “having” and any variations thereof are intended to cover, but not exclusively, inclusion, for example, a product or device including a series of components does not have to be limited to the clearly listed components, but can include other components that are not clearly listed or inherent to these products or devices.

[0040] It should be noted in the description of the present application that, unless otherwise specified and limited, the terms “mounting”, “connecting”, “connecting” should be understood in a broad sense, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium, or it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0041] The following disclosure provides many different embodiments or examples for implementing different structures of the present application. In order to simplify the disclosure of the present application, the components and settings of specific examples are described below. Of course, they are only examples, and the purpose is not to limit the present application. In addition, the present application can repeatedly refer to the same reference numerals and / or reference letters in different examples. Such repetition is for the purpose of simplification and clarity, and does not itself indicate a relationship between the various embodiments and / or settings discussed. In addition, the present application provides examples of various specific processes and materials, but those skilled in the art can realize the application of other processes and / or the use of other materials.

[0042] The display device provided by the embodiments of the present application can have various implementation forms, for example, it can be a television, a smart television, a vehicle-mounted display screen, a monitor, a head-mounted display device, a tablet computer or a notebook computer, etc. Figure 1 A specific embodiment of the display device of the present application is shown.

[0043] Figure 1 The structural schematic diagram of the display device provided by the embodiment of the present application is shown in the following figure. Taking a MiniLED RGB three-color backlight television as an example, Figure 1 The structural schematic diagram of the display screen cross section provided by the embodiment of the present application is shown in the above figure. The display screen includes a display panel and a backlight module. The backlight module includes a back plate, a lamp plate (including, for example, Figure 1 a backlight LED lamp bead array shown in the following figure), a support, and a light control component such as a honeycomb plate, a reflecting sheet, a diffusion plate, and a film sheet. As shown in the figure, each backlight LED lamp bead includes a red, green, and blue three-color lamp group. Through independent control of the backlight, precise local dimming and wide color gamut display can be achieved.

[0044] Figure 2 The driving architecture schematic diagram of the display device provided by the embodiment of the present application is shown in the following figure. The controller in the present application takes a system on chip (SOC) 01 as an example. Specifically, after preliminary processing of the image input signal, R / G / B input signals are obtained. Subsequently, partition pixel statistics, partition backlight calculation and processing, and dynamic color gamut matrix calculation are sequentially performed. Finally, based on the dynamic color gamut matrix, the R / G / B input signals are partitioned and color converted to obtain R / G / B output signals.

[0045] Among them, the signal processed by the system on chip 01 is output in two ways: one way is to send the backlight duty cycle data to the backlight module 02, so that the backlight driving circuit / MCU 03 (Microcontroller Unit) in the backlight module 02 drives the backlight light source, that is, the RGB three-color LED 04, to emit light for backlight; the other way is to send the R / G / B output signals after color conversion to the display panel 05, so that the TCON 06 (Timing Controller) in the display panel 05 drives the liquid crystal panel 07 for pixel driving to display images.

[0046] The above architecture can improve the accuracy of color display by cooperatively processing the backlight brightness and the front-end signal color conversion. Each backlight partition can perform color display under an independent dynamic color gamut matrix, thereby improving the accuracy of color display.

[0047] With the development of display technology, MiniLED backlight has become the core solution to improve television picture quality due to its high brightness, high contrast, and dynamic area light control capability. RGB three-color backlight (red, green, and blue independent light control) can further expand the color gamut by adjusting the RGB light emission ratio of each partition, thereby achieving more rich color performance. Figure 3 The color gamut contrast difference schematic diagram provided by the embodiment of the present application is shown in the following figure. As shown in the figure, Figure 3As shown, RGB backlight display can improve color gamut range when performing area dimming technology, where the green line is the color gamut under RGB sub-control, and the red line is the color gamut under RGB sub-control.

[0048] In related technologies, the color management of liquid crystal televisions usually uses a fixed color space conversion matrix (FCSM) for color calibration. This scheme assumes that the color gamut of the display device is constant in the full screen range, and converts the source signal to the target color gamut (such as the color gamut of the television backlight) through a pre-calculated matrix. However, each sub-zone of a MiniLED RGB backlight can independently adjust the RGB light ratio, resulting in dynamic changes in the actual color gamut of different sub-zones (such as color gamut shift towards red when red light is enhanced). The fixed matrix cannot adjust to the real-time color gamut of each sub-zone, resulting in color distortion.

[0049] The technical content provided by the present application aims to solve the above technical problems in the related art. In the display device and color conversion method provided by the embodiments of the present application, the method comprises: obtaining the duty cycle of each backlight sub-zone in the display device; for each backlight sub-zone, determining the dynamic color gamut vertex of the backlight sub-zone based on the duty cycle of the backlight sub-zone and the color gamut range of the display device under the backlight sub-zone, and determining the dynamic color gamut matrix corresponding to the backlight sub-zone according to the dynamic color gamut vertex; and performing color conversion on the input image signal of the backlight sub-zone based on the dynamic color gamut matrix corresponding to the backlight sub-zone. When the input image signal in the backlight sub-zone causes the duty cycle to change, the dynamic color gamut vertex and the dynamic color gamut matrix can change synchronously, and the dynamic color gamut matrices corresponding to at least two backlight sub-zones are different, which can achieve more refined color management for different backlight states of each backlight sub-zone, can improve the local contrast and color saturation of the picture, and the calculation of the dynamic color gamut vertex takes into account the color gamut range of the hardware device, reducing the color coordinate offset caused by the fixed color gamut matrix, thereby improving the accuracy of color display.

[0050] The following takes the controller of the display device as an example to illustrate how the display device performs color conversion.

[0051] The technical solutions of the present application will be described in detail below in conjunction with specific embodiments. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described in detail in some embodiments.

[0052] Figure 4 The flowchart of the color conversion method provided by the embodiments of the present application is shown in FIG. 1. Figure 4 As shown, the method comprises the following steps:

[0053] S101, obtain duty cycles of a plurality of backlight partitions in a display device; wherein the duty cycles are determined based on input image signals of the backlight partitions;

[0054] S102, determine dynamic gamut vertices of the backlight partitions based on the duty cycles of the backlight partitions and color gamut ranges of the display device under the backlight partitions, and determine dynamic gamut matrices corresponding to the backlight partitions according to the dynamic gamut vertices;

[0055] S103, perform color conversion on the input image signals of the backlight partitions based on the dynamic gamut matrices corresponding to the backlight partitions; wherein the dynamic gamut matrices corresponding to at least two backlight partitions are different.

[0056] In some embodiments, the execution subject of the color conversion method is usually a controller inside the display device, which can be a dedicated image processing chip, or a special processing core or software module integrated in the system master chip. In actual application, the controller can perform basic image processing tasks such as signal receiving and decoding, motion compensation, scaling, and gray scale mapping in addition to implementing the method of the present solution.

[0057] In some embodiments, the area and number of the backlight partitions are determined by the hardware design of the display device. In production and manufacturing, the light-emitting units behind the display panel are divided into hundreds, thousands or even more independent physical areas, each of which is a backlight partition. For example, the area division can be a uniform grid, such as dividing the screen into rectangular blocks, or adjusting adaptively according to image content. Correspondingly, the image picture is also divided into logical areas corresponding to the physical backlight partitions one by one.

[0058] Wherein, the duty cycle of the backlight partition can be understood as the backlight value of the backlight component, which can be the duty cycle of the driving voltage signal to control the on-off of the power circuit of the backlight component, or the current duty cycle flowing through the lamp beads to control the current size.

[0059] In some embodiments, the controller will analyze the brightness information of all pixel points in the image area corresponding to each backlight partition to obtain the corresponding duty cycle. Specifically, by calculating the eigenvalues of the red, green and blue components in the backlight partition, such as the maximum value, the average value or using algorithms such as brightness histogram analysis, and then mapping or converting the eigenvalues, the red duty cycle, the green duty cycle and the blue duty cycle required for driving the backlight partition are determined. Correspondingly, the brightness of the backlight is determined by the image content of the corresponding area, and the partition duty cycle is high in bright scenes and low in dark scenes.

[0060] In some embodiments, the color gamut range of a display device under a backlight partition is typically obtained through factory calibration, stored as boundary points in a color space, such as the vertex coordinates of an RGB color gamut. Wherein, the color gamut range can be dynamically adjusted due to the backlight brightness affecting color saturation and brightness when the duty cycle changes. Specifically, the method of determining the dynamic color gamut vertex can be through a lookup table or a mathematical function, mapping the current duty cycle to the corresponding vertex coordinates. For example, when the duty cycle is high, the color gamut vertex can be expanded outward to utilize a wider color range, while when the duty cycle is low, the vertex can be retracted to maintain color accuracy.

[0061] It should be understood that the dynamic color gamut vertex can be understood as a boundary point of the color range that the display device can present under the current backlight condition, such as the key coordinates defining the color gamut polygon in the color space. Wherein, the dynamic color gamut matrix corresponding to the backlight partition is determined according to the dynamic color gamut vertex, which is typically through constructing a color transformation matrix to convert the input image signal from the standard color gamut (such as sRGB) to the dynamic color gamut. In practical applications, the determination of the dynamic color gamut matrix can be based on linear algebra methods, such as calculating the conversion matrix from the source color gamut to the target color gamut through the vertex coordinates. It should be understood that the dynamic color gamut matrix is a 3x3 or similar transformation matrix used to adjust the RGB values to adapt to the color gamut shift caused by the change in backlight.

[0062] In some embodiments, when performing color conversion on the input image signal of the backlight partition, a matrix operation is applied to represent each pixel within the partition to adjust its color value. Wherein, the color conversion is to map the color coordinates in the input signal to the new dynamic color gamut through matrix multiplication, thereby compensating for the impact of backlight brightness changes on color representation. For example, if the low duty cycle causes the color gamut to shrink, the conversion can scale the color values through the matrix to avoid color distortion.

[0063] In some optional embodiments, color conversion is typically performed independently for the color optimization of each partition, wherein smoothing processing of the partition boundary can be considered to avoid visible color discontinuity or artifacts.

[0064] The color conversion method provided in the embodiments of the present application comprises: acquiring a duty cycle of each backlight partition in a display device; determining a dynamic gamut vertex of each backlight partition based on the duty cycle of the backlight partition and a gamut range of the display device under the backlight partition, and determining a dynamic gamut matrix corresponding to the backlight partition according to the dynamic gamut vertex; and performing color conversion on an input image signal of the backlight partition based on the dynamic gamut matrix corresponding to the backlight partition. In the scheme of the present application, when the input image signal in the backlight partition causes the duty cycle to change, the dynamic gamut vertex and the dynamic gamut matrix can change synchronously, and the dynamic gamut matrices corresponding to at least two backlight partitions are different, so that more refined color management can be implemented for different backlight states of each backlight partition, the local contrast and color saturation of a picture can be improved, the calculation of the dynamic gamut vertex takes the gamut range of a hardware device into account, the color coordinate offset caused by a fixed gamut matrix is reduced, and thus the accuracy of color display is improved.

[0065] As a further example, on the basis of any of the examples, step S101 specifically comprises:

[0066] The red duty cycle, the green duty cycle and the blue duty cycle of the backlight partition are determined according to the maximum red pixel value, the maximum green pixel value and the maximum blue pixel value in the backlight partition.

[0067] In some embodiments, an overall brightness factor is introduced for backlight calculation. For example, the overall duty cycle of the backlight partition can be calculated first, which can be obtained by taking the maximum value of the maximum red pixel value, the maximum green pixel value and the maximum blue pixel value, or calculating a certain weighted average of them. Then, the duty cycles of red, green and blue are determined respectively based on the overall duty cycle and the relative proportions of the maximum pixel values of each color. The specific calculation formula can be that the maximum pixel value of each color is divided by the maximum value of the three to obtain a proportion coefficient, and then the proportion coefficient is multiplied by the overall duty cycle to obtain the independent duty cycle of each color. This method helps to maintain the balance between different color backlights and avoid color distortion or a sharp increase in power consumption due to excessive brightness of a single color.

[0068] In some optional embodiments, the duty cycle of each color is set to the maximum pixel value of the color channel itself, that is, the red duty cycle is equal to the maximum value of the red component of all pixels in the partition, and the green and blue duty cycles are determined in the same way. This scheme is simple and efficient, and can accurately reflect the highest brightness requirement of each primary color for the partition. In actual application, subsequent normalization or scaling processing may be required to match the actual input range of the backlight driver.

[0069] The scheme of the present example realizes more refined control of the backlight by refining the determination of the duty cycle from the overall brightness to the maximum pixel values corresponding to the red, green and blue primary colors, thereby helping to more accurately match the color intent of the input signal.

[0070] Figure 5 A flowchart of the color conversion method according to an embodiment of the present application is shown in FIG. 1. As shown in the figure, the method comprises the following steps S101-S103. Figure 5

[0071] S201, sum the product of the maximum red pixel value in the backlight partition and the first weight, and the product of the average red pixel value in the backlight partition and the second weight, and take the sum as the red duty cycle; wherein the sum of the first weight and the second weight is 1;

[0072] S202, sum the product of the maximum green pixel value in the backlight partition and the first weight, and the product of the average green pixel value in the backlight partition and the second weight, and take the sum as the green duty cycle;

[0073] S203, sum the product of the maximum blue pixel value in the backlight partition and the first weight, and the product of the average blue pixel value in the backlight partition and the second weight, and take the sum as the blue duty cycle.

[0074] In the present example, by introducing the weighted sum of the maximum pixel value and the average pixel value, the formula can more intelligently respond to the image content characteristics within the backlight partition. When the maximum pixel value weight is high, the backlight output will pay more attention to ensuring that the brightest part of the color in the partition does not lose details due to insufficient backlight, which is particularly beneficial to the performance of bright objects in high-contrast images. When the average pixel value weight is high, the backlight output will be more consistent with the average brightness level of the entire partition, helping to maintain the uniformity and naturalness of the overall picture, and avoiding waste of power consumption or halo phenomenon due to local over-brightness.

[0075] In some embodiments, the specific sizes of the first weight and the second weight can be determined by engineers through system debugging and picture quality evaluation. Specifically, the engineers will try different weight combinations, for example, set the first weight to zero point seven and the second weight to zero point three, or use a balanced ratio of five to five, and then observe the display effect under various scenes. The evaluation focuses on whether the highlight part is overexposed or lacks details, the contrast performance in dark scenes, and the smoothness of backlight changes when switching between different scenes. The finally determined weight values will be fixed in the firmware or lookup table of the display device.

[0076] For example, the calculation formula of the red duty cycle in the kth backlight partition can be:

[0077] ​

[0078] wherein, , are the maximum red pixel value and the average red pixel value in the kth backlight partition, respectively; and are the first weight and the second weight, respectively; similarly, the green duty cycle and the blue duty cycle can be obtained.

[0079] In some alternative embodiments, in addition to the red, green and blue backlights, the display device can also employ other types of backlight structures, such as white backlight or wide color gamut backlight system with other primary colors mixed in.

[0080] For the white backlight, the calculation of its duty cycle can refer to the basic idea of the present scheme. Since the white backlight has only one control channel, its duty cycle can be calculated based on the red, green and blue pixel values. One method is to first calculate the red duty cycle, the green duty cycle and the blue duty cycle according to the present scheme, respectively, and then take the maximum value among the three as the white duty cycle of the partition, to ensure that the backlight brightness can cover the needs of all color channels. Another method is to take a weighted average of the calculated red, green and blue duty cycles to obtain a more representative overall brightness level.

[0081] For the case of wide color gamut backlight with added yellow, cyan or magenta light sources, the calculation process of the backlight of any one of the red, green and blue colors of the present example can be referred to.

[0082] The scheme of the present example calculates the duty cycles of each color by weighted summation of the maximum value and the average value, while taking into account both the peak brightness requirement of the picture and the overall brightness basis, improving the authenticity and balance of the color duty cycle.

[0083] Figure 6 A flowchart of the color conversion method according to an embodiment of the present application is shown in FIG. 1. As shown in FIG. 1, the method further comprises the following steps: Figure 6

[0084] S301, calculating a red normalized value according to the red duty cycle, the total duty cycle and the difference amplification coefficient, and updating the red duty cycle to the red normalized value; wherein the total duty cycle is determined according to the red duty cycle, the green duty cycle and the blue duty cycle;

[0085] S302, calculating a green normalized value according to the green duty cycle, the total duty cycle and the difference amplification coefficient, and updating the green duty cycle to the green normalized value;

[0086] S303, calculating a blue normalized value according to the blue duty cycle, the total duty cycle and the difference amplification coefficient, and updating the blue duty cycle to the blue normalized value. ​

[0087] In some embodiments, the sum of the red duty cycle, the green duty cycle and the blue duty cycle can be taken as the total duty cycle. Alternatively, the square root of the sum of the squares of the red duty cycle, the green duty cycle and the blue duty cycle can also be taken as the total duty cycle, so as to make the total duty cycle more balanced and help improve the overall coordination of the picture.

[0088] For example, the difference amplification coefficient is a preset amplification factor, which artificially amplifies the relative difference between the duty cycles of different colors in the normalization process. In practical applications, an empirical balance point between color enhancement effect and color authenticity can be obtained through experimental debugging and visual evaluation, and the difference amplification coefficient can be finally determined through repeated picture quality tests. Specifically, the difference amplification coefficient can be preset to 3 to significantly enhance the saturation of colors.

[0089] For example, the red normalization value may be:

[0090]

[0091] wherein, is the red duty cycle of the kth backlight partition before updating, is the green duty cycle of the kth backlight partition before updating, is the blue duty cycle of the kth backlight partition before updating, is the total duty cycle, is the difference amplification coefficient. Similarly, the green normalization value and the blue normalization value can be obtained, i.e. and .

[0092] The scheme of the present example synchronously updates the duty cycles of red, green and blue based on a unified difference amplification coefficient, which can uniformly amplify or reduce the duty cycle difference of each primary color relative to the total duty cycle on the basis of normalization processing of the duty cycle.

[0093] As another example, on the basis of any of the examples, the color gamut range of the display device in the backlight partition includes an interval from a first color gamut to a second color gamut; wherein,

[0094] The first color gamut is a color gamut defined by the red first coordinate, the green first coordinate and the blue first coordinate in the chromaticity diagram when the display device displays a first brightness and a preset red color, a preset green color or a preset blue color in the backlight partition;

[0095] ​The second color gamut is the color gamut defined by the red second coordinate, green second coordinate, and blue second coordinate in the chromaticity diagram when the display device displays white under the backlight zone and the display brightness is the second brightness; wherein, the second brightness is less than the first brightness.

[0096] In some embodiments, the first brightness is typically set to the maximum brightness achievable by the backlight zone. This is the peak brightness that the display device can achieve when driving a single primary color, used to define the upper limit of its highlight performance capability. For example, "preset red" refers to the limit of color that can be displayed under this backlight zone when the red component of the image signal is at its maximum value, while the green and blue components are zero. Optionally, the first brightness can also be any brightness within the hardware brightness peak range.

[0097] In this example, the first color gamut is the triangular area enclosed by the coordinates of pure red, pure green, and pure blue on the chromaticity diagram, namely the first coordinates of red, green, and blue. It represents the widest color boundary that the display device can achieve in that zone when the backlight zone drives a single primary color at its highest capability, and can be regarded as the theoretical maximum color gamut of this zone at high peak brightness.

[0098] Among them, the first red coordinate, the first green coordinate, and the first blue coordinate are ( , ), ( , ), ( , ); The red second coordinate, the green second coordinate, and the blue second coordinate are ( , ), ( , ), ( , ).

[0099] In some embodiments, the second brightness can be a fixed minimum brightness of the standard display, or it can be a dynamically adjusted reference point determined experimentally during the system design phase. For example, it can be selected as a percentage of the maximum brightness (such as 10% or 20%), or a specific nit value that ensures good color stability. Correspondingly, "display brightness is the second brightness and display color is white" is usually standard white light. The red, green, and blue second coordinates measured at this time reflect the actual chromaticity characteristics of each primary color emitting unit when white is mixed at a lower brightness.

[0100] Therefore, at lower brightness levels, the range of colors that a device can display becomes narrower. This color gamut, defined by the coordinates of each primary color measured against a white screen, is the lower limit of the color gamut that the device can stably and accurately display colors under these low brightness conditions; below this limit, colors may be severely distorted.

[0101] The scheme in this example limits the color gamut range of the display device under the backlight zone to the interval between the first color gamut and the second color gamut. It quantifies the offset of the color gamut range of the display device as brightness changes, which can improve the accuracy of subsequent calculation of dynamic color gamut vertices, thereby providing more accurate boundary conditions for color conversion.

[0102] Figure 7 This document provides a schematic flowchart of a color conversion method according to an embodiment of this application. Exemplarily, the dynamic color gamut vertices include: red vertex coordinates, green vertex coordinates, and blue vertex coordinates; as shown... Figure 7 As shown, step S102 in this method specifically includes the following steps:

[0103] S401. Determine the coordinates of the red vertex based on the red duty cycle, the first red coordinate, and the second red coordinate.

[0104] S402. Determine the coordinates of the green vertex based on the green duty cycle, the first green coordinate, and the second green coordinate.

[0105] S403. Determine the coordinates of the blue vertex based on the blue duty cycle, the first coordinate of the blue vertex, and the second coordinate of the blue vertex.

[0106] It is understandable that the core idea of ​​determining the red vertex coordinates based on the red duty cycle, the first red coordinate, and the second red coordinate is to establish a mapping function that allows the vertex coordinates to move smoothly within the interval defined by the first red coordinate and the second red coordinate as the duty cycle changes.

[0107] In some embodiments, vertex coordinates can be determined using a non-linear interpolation method. For example, the coordinates (x-coordinate) of the red vertex in a standard chromaticity diagram... and y coordinate They can be respectively:

[0108]

[0109]

[0110] in, The red duty cycle is ( ) is the first red coordinate, ( The red second vertex coordinate is shown; similarly, the green vertex coordinates (x-coordinate) can be calculated. and y coordinate ), a blue vertex coordinate (x coordinate and y coordinate ).

[0111] wherein the formula is a weighted average of the red first coordinate and the red second coordinate by taking the red duty cycle as a key weighting factor. Specifically, the red duty cycle directly participates in the calculation, and when the red duty cycle is large, the weighted result will be more inclined to the red first coordinate, which means that under high backlight brightness, the red vertex will tend to the red first coordinate representing the maximum color capability of the hardware, so as to obtain more saturated red performance. Conversely, when the red duty cycle is small, the calculation result will be close to the red second coordinate, reflecting the contraction of the color gamut range under low backlight brightness. This dynamic adjustment ensures the matching of color performance and backlight state.

[0112] In some optional embodiments, the vertex coordinates can also be determined by a non-linear difference method. Specifically, the current red duty cycle needs to be normalized to a standard range, for example, between zero and one. The normalization process needs to map the actual duty cycle to a proportion coefficient according to the minimum and maximum values that the red duty cycle can take. Subsequently, a linear interpolation calculation is performed between the red first coordinate and the red second coordinate using the proportion coefficient, that is, the red vertex coordinate is equal to the red second coordinate plus the product of the proportion coefficient and the difference between the red first coordinate and the red second coordinate.

[0113] In actual application, the key parameters of the red first coordinate and the red second coordinate can be stored in the non-volatile memory of the display controller as device characteristic parameters. The red first coordinate corresponds to the chroma value when the backlight partition displays the preset red at the highest driving brightness, and the red second coordinate corresponds to the red component chroma value that can be reached when displaying white at a lower reference brightness. In actual calculation, the controller reads these preset coordinate values from the memory and substitutes them into the selected formula together with the real-time calculated red duty cycle to finally dynamically determine the optimal red vertex coordinate under the current backlight state.

[0114] The scheme of the present example determines the dynamic color gamut vertex by mapping the dynamic duty cycle of each color to the corresponding preset color gamut boundary coordinates, realizes the continuous and adaptive adjustment of the color gamut range determined by the dynamic color gamut vertex with the change of backlight brightness, and thus can improve the accuracy and color consistency of the color conversion reference.

[0115] Figure 8 A flowchart of the color conversion method according to an embodiment of the present application is shown in FIG. 1. As shown in FIG. 1, the method further includes the following steps: Figure 8

[0116] S501, obtaining a target color gamut matrix; ​

[0117] Step S102 specifically includes:

[0118] S502, determining a source gamut matrix according to the dynamic gamut vertex, and calculating a dynamic gamut matrix according to the source gamut matrix and the target gamut matrix;

[0119] Step S103 specifically includes:

[0120] S503, processing the inverse of the dynamic gamut matrix and the input image signal of the backlight partition to complete the color conversion.

[0121] In some embodiments, the target gamut matrix can be pre-stored in the memory and read in real time when color conversion is needed. The target gamut matrix is a fixed 3x3 matrix that defines the characteristics of the target color space to be achieved by color conversion, such as the standard sRGB gamut or Rec.709 gamut.

[0122] In this example, the source gamut matrix is constructed by the chroma coordinates of the three vertexes and a pre-defined or calculated white point coordinate, which accurately describes the actual color space characteristics of the display device in the current working state.

[0123] Further, the calculation of the dynamic gamut matrix is achieved by matrix multiplication between the target gamut matrix and the inverse of the source gamut matrix. The mathematical meaning of this calculation process is to solve a transformation matrix that can linearly convert image signals from the current source gamut of the device to the desired target gamut, thereby maintaining the consistency of color appearance under varying backlight conditions.

[0124] Finally, in the step of processing the inverse of the dynamic gamut matrix and the input image signal of the backlight partition to complete the color conversion, the specific implementation is to apply the inverse of the dynamic gamut matrix to the multiplication operation of the vector composed of the red, green and blue values of each pixel of the input image signal. In practical applications, the controller will perform vector-matrix multiplication for each pixel to calculate the new red, green and blue values after conversion. This process needs to traverse all pixels in the backlight partition one by one to ensure that the colors of the entire partition are accurately adjusted.

[0125] An exemplary dynamic gamut matrix It can be calculated by the following formula:

[0126]

[0127] Wherein, is the target gamut matrix, is a source gamut matrix, is the inverse of the matrix;

[0128] Further, the inverse of the dynamic gamut matrix and the input image signal of the backlight partition are multiplied by the corresponding matrix to obtain the output signal .

[0129]

[0130] The scheme of the present example calculates the conversion relationship through the dynamically generated source gamut matrix (representing the actual gamut under the current backlight) and the target gamut matrix (representing the standard gamut of the output signal), which can realize the mapping of the input image signal to the output image signal.

[0131] Figure 9 The flowchart of the color conversion method according to the present application is shown in FIG. 1. As shown in FIG. 1, the method comprises the following steps: Figure 9

[0132] S601, based on the white vertex coordinates and the fixed white Y value of 1, calculating the white X value and the white Z value according to the primary color conversion algorithm; wherein in the primary color conversion algorithm, the X value is determined based on the vertex coordinates and the Y value, and the Z value is determined based on the vertex coordinates and the Y value;

[0133] S602, determining an initial matrix based on the dynamic gamut vertex, and determining the scaling coefficient according to the initial matrix and the white Y value, the white X value and the white Z value;

[0134] S603, calculating the source gamut matrix according to the scaling coefficient and the initial matrix.

[0135] Exemplarily, the white vertex coordinates represent the target white point defined by the display device under the current dynamic backlight state, and the standard illuminant such as D65 chromaticity coordinates is usually adopted. The coordinates can be measured in advance in the factory calibration stage of the display device and stored in the firmware.

[0136] Exemplarily, the two-dimensional chromaticity coordinates of the white vertex coordinates can be expanded to three-dimensional linear light tristimulus values by the following formula, when the white vertex coordinates are , the white Y value, i.e. 1, the corresponding white X value, i.e. , and the white Z value, i.e. The calculation formula is as follows:

[0137]

[0138]

[0139] ​​The initial matrix is determined The scaling coefficients The calculation formula is as follows:

[0140]

[0141] Wherein, The inverse of the matrix; wherein, when the set of scaling coefficients acts on the initial matrix, it can ensure that when the input signal is the maximum value, i.e. white, the output after matrix transformation is exactly equal to the target white tristimulus value. The set of scaling coefficients is essentially a calibration factor, so that the color conversion matrix constructed can accurately map the device's own primary color system to the standard tristimulus value system.

[0142] Further, the calculation formula of the source gamut matrix

[0143]

[0144] Wherein, The transpose of the scaling coefficient Wherein, the obtained source gamut matrix describes the linear transformation relationship between the red, green and blue primary colors of the display device and the standard color space under the current specific duty cycle. This source gamut matrix is dynamically changing, which can adapt to the backlight state in real time and provide an accurate starting point for the next step of calculating the overall conversion matrix to the target gamut.

[0145] The scheme of the present example realizes white point calibration by calculating the complete white point tristimulus value through the white vertex coordinates and the fixed Y value, and further determining the scaling coefficient to construct the matrix, thereby improving the accuracy of the source gamut matrix calculation.

[0146] Figure 10 The flowchart of the color conversion method provided by the present application is shown in the figure. The dynamic gamut vertex includes red vertex coordinates, green vertex coordinates and blue vertex coordinates; as shown in Figure 10 The method specifically includes the following steps:

[0147] S701, calculating the red Y value according to the red duty cycle and the brightness coefficient, calculating the green Y value according to the green duty cycle and the brightness coefficient, and calculating the blue Y value according to the blue duty cycle and the brightness coefficient;

[0148] S702, calculating the red X value and the red Z value based on the red vertex coordinates and the red Y value according to the primary color conversion algorithm, calculating the green X value and the green Z value based on the green vertex coordinates and the green Y value, and calculating the blue X value and the blue Z value based on the blue vertex coordinates and the blue Y value, to construct an initial matrix.

[0149] For example, the calculation formula of the red Y value is as follows:​

[0150]

[0151] wherein, is the red duty cycle, is the luminance coefficient, which can be 100 or empirically calibrated;

[0152] The corresponding red X value and red Z value are:

[0153]

[0154]

[0155] wherein, is the red vertex coordinate; correspondingly, the green X value , the green Y value , the green Z value , the blue X value , the blue Y value , the blue Z value can be obtained to construct an initial matrix :

[0156]

[0157] In actual applications, the above calculation formula and calculation process can be fine-tuned according to the operating parameters or hardware models of the device.

[0158] The scheme of the present example converts the dynamic duty cycles of each primary color into its corresponding luminance component (Y value), and combines it with the chrominance coordinates to construct an initial matrix. The three stimulus values on which the color gamut conversion is based can more accurately reflect the actual light energy distribution under the current backlight, thereby improving the coordination of the display colors.

[0159] Figure 11 is a structural schematic diagram of a color conversion device provided by the present application. As shown in Figure 11 , the device comprises:

[0160] The acquisition module 11 is configured to acquire the duty cycle of each backlight partition in the display device; wherein the duty cycle is determined based on the input image signal of the backlight partition;

[0161] The calculation module 12 is configured to determine, for each backlight partition, the dynamic color gamut vertex of the backlight partition based on the duty cycle of the backlight partition and the color gamut range of the display device under the backlight partition, and determine the dynamic color gamut matrix corresponding to the backlight partition according to the dynamic color gamut vertex;

[0162] The conversion module 13 is configured to perform color conversion on the input image signal of each backlight partition based on the dynamic color gamut matrix corresponding to the backlight partition.

[0163] The color conversion device provided by the embodiments of the present application can execute the color conversion method in the method embodiments, and the implementation principle and technical effects are similar, which will not be described here again. It should be noted that the above Figure 11 The division of each module shown is only a schematic, and the division of each module and the naming of each module by the present application are not limited.

[0164] The present application also provides a computer readable storage medium, which can include: a U disk, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, and various storage program codes. Specifically, the computer readable storage medium stores program instructions, and the program instructions are used for the method in the above embodiments.

[0165] The present application also provides a program product, which includes execution instructions stored in a readable storage medium. At least one control module of the display device can read the execution instructions from the readable storage medium, and the at least one control module executes the execution instructions to make the display device implement the handwriting erasing method provided by the various embodiments.

[0166] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, but not to limit them; although the present application has been described in detail with reference to the above embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the above embodiments, or make equivalent replacement for part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

[0167] In order to facilitate explanation, the above description has been made in combination with specific embodiments. However, the above exemplary discussion is not intended to exhaust or limit the embodiments to the specific forms disclosed above. According to the above teachings, various modifications and variations can be obtained. The selection and description of the above embodiments are to better explain the principles and practical applications, so that those skilled in the art can better use the embodiments and various different modified embodiments suitable for specific use considerations.

Claims

1. A display device, characterized by comprising: The display device comprises: a controller configured to: acquire duty cycles of a plurality of backlight partitions in the display device; wherein the duty cycles are determined based on input image signals of the backlight partitions; determine dynamic color gamut vertices of the backlight partitions based on the duty cycles of the backlight partitions and color gamut ranges of the display device under the backlight partitions, and determine dynamic color gamut matrices corresponding to the backlight partitions according to the dynamic color gamut vertices; wherein the color gamut ranges of the display device under the backlight partitions comprise intervals from a first color gamut to a second color gamut; the first color gamut is a color gamut defined by first coordinates of each preset primary color in a corresponding chromaticity diagram when the display device displays a first brightness and each preset primary color under the backlight partitions; the second color gamut is a color gamut defined by second coordinates of each preset primary color in the corresponding chromaticity diagram when the display device displays a second brightness and white color under the backlight partitions; the second brightness is less than the first brightness; each vertex coordinate of the dynamic color gamut vertices is determined according to the duty cycles, the first coordinates and the second coordinates of each preset primary color in the backlight partitions; perform color conversion on input image signals of the backlight partitions based on the dynamic color gamut matrices corresponding to the backlight partitions; wherein the dynamic color gamut matrices corresponding to at least two backlight partitions are different; a backlight module connected to the controller, the backlight module comprising a plurality of backlight light sources configured to control the backlight light sources to emit light according to the duty cycles of the plurality of backlight partitions; the backlight light sources comprising at least two types of light emitting chips emitting light rays of different wavelengths; a display panel connected to the controller and configured to display the image signals after color conversion.

2. The display device according to claim 1, wherein The controller is configured to: determine red duty cycles, green duty cycles and blue duty cycles of the backlight partitions according to maximum red pixel values, maximum green pixel values and maximum blue pixel values in the backlight partitions.

3. The display device according to claim 2, wherein The controller is configured to: sum a product of the maximum red pixel values in the backlight partitions and a first weight with a product of average red pixel values in the backlight partitions and a second weight, and take a sum result as the red duty cycles; wherein a sum of the first weight and the second weight is 1; sum a product of the maximum green pixel values in the backlight partitions and the first weight with a product of average green pixel values in the backlight partitions and the second weight, and take a sum result as the green duty cycles; sum a product of the maximum blue pixel values in the backlight partitions and the first weight with a product of average blue pixel values in the backlight partitions and the second weight, and take a sum result as the blue duty cycles.

4. The display device according to claim 2, wherein The controller is configured to: calculate a red normalized value according to the red duty cycles, a total duty cycle and a difference expansion coefficient, and update the red duty cycles to the red normalized value; wherein the total duty cycle is determined according to the red duty cycles, the green duty cycles and the blue duty cycles. calculating a green normalized value according to the green duty cycle, the total duty cycle and the difference amplification factor, and updating the green duty cycle as the green normalized value; calculating a blue normalized value according to the blue duty cycle, the total duty cycle and the difference amplification factor, and updating the blue duty cycle as the blue normalized value.

5. The display device according to claim 2, wherein The color gamut range of the display device under the backlight partition includes an interval from a first color gamut to a second color gamut; wherein, The first color gamut is a color gamut defined by red first coordinates, green first coordinates and blue first coordinates in a corresponding chromaticity diagram when the display device displays a first brightness and a preset red color, a preset green color or a preset blue color under the backlight partition; The second color gamut is a color gamut defined by red second coordinates, green second coordinates and blue second coordinates in the corresponding chromaticity diagram when the display device displays a second brightness and a white color under the backlight partition; wherein, the second brightness is less than the first brightness.

6. The display device according to claim 5, wherein The dynamic color gamut vertex includes red vertex coordinates, green vertex coordinates and blue vertex coordinates; the controller is configured to: determine the red vertex coordinates according to the red duty cycle, the red first coordinates and the red second coordinates; determine the green vertex coordinates according to the green duty cycle, the green first coordinates and the green second coordinates; determine the blue vertex coordinates according to the blue duty cycle, the blue first coordinates and the blue second coordinates.

7. The display device according to claim 2, wherein The controller is configured to: obtain a target color gamut matrix; determine a source color gamut matrix according to the dynamic color gamut vertex, and calculate the dynamic color gamut matrix according to the source color gamut matrix and the target color gamut matrix; process the inverse of the dynamic color gamut matrix and an input image signal of the backlight partition to complete color conversion.

8. The display device according to claim 7, wherein The controller is configured to: calculate white X value and white Z value according to a primary color conversion algorithm based on white vertex coordinates and a fixed white Y value of 1; wherein, X value is determined based on vertex coordinates and Y value in the primary color conversion algorithm, and Z value is determined based on vertex coordinates and Y value; determine a scaling coefficient according to an initial matrix, the white Y value, the white X value and the white Z value based on the dynamic color gamut vertex; calculate the source color gamut matrix according to the scaling coefficient and the initial matrix.

9. The display device of claim 8, wherein, The dynamic color gamut vertex includes red vertex coordinates, green vertex coordinates and blue vertex coordinates; the controller is configured to: calculate red Y value according to the red duty cycle and a brightness coefficient, calculate green Y value according to the green duty cycle and the brightness coefficient, and calculate blue Y value according to the blue duty cycle and the brightness coefficient; calculate red X value and red Z value based on the red vertex coordinates and the red Y value, calculate green X value and green Z value based on the green vertex coordinates and the green Y value, and calculate blue X value and blue Z value based on the blue vertex coordinates and the blue Y value according to the primary color conversion algorithm, to construct the initial matrix.

10. A color conversion method characterized by, It includes: Obtaining a duty cycle of a backlight partition in a display device; wherein the duty cycle is determined based on an input image signal of the backlight partition; Determining a dynamic color gamut vertex of the backlight partition based on the duty cycle of the backlight partition and a color gamut range of the display device under the backlight partition, and determining a dynamic color gamut matrix corresponding to the backlight partition according to the dynamic color gamut vertex; wherein the color gamut range of the display device under the backlight partition comprises an interval from a first color gamut to a second color gamut; the first color gamut is a color gamut defined by first coordinates of each preset primary color in a corresponding chromaticity diagram when the display device displays a first brightness and each preset primary color under the backlight partition; the second color gamut is a color gamut defined by second coordinates of each preset primary color in the corresponding chromaticity diagram when the display device displays a second brightness and white color under the backlight partition; the second brightness is less than the first brightness; each vertex coordinate of the dynamic color gamut vertex is determined according to the duty cycle, the first coordinates and the second coordinates of each preset primary color in the backlight partition; Performing color conversion on the input image signal of the backlight partition based on the dynamic color gamut matrix corresponding to the backlight partition; wherein the dynamic color gamut matrices corresponding to at least two backlight partitions are different.

Images