Distance calculation circuit and grayscale compensation method

Abstract

This disclosure provides a distance calculation circuit and a grayscale compensation method. The distance calculation circuit includes a distance calculation module, which includes a first arithmetic unit, a shifter, a second arithmetic unit, a third adder, and a register. One input terminal of the first arithmetic unit is input to the coordinates of a target pixel in the current backlight partition in the target direction, and the other input terminal is input to the distance between the current backlight partition and the target backlight partition in the target direction. The first arithmetic unit performs addition or subtraction operations. The shifter is connected to the output terminal of the first arithmetic unit and is used to shift a first distance value. One input terminal of the second arithmetic unit is connected to the output terminal of the shifter, and the other input terminal is connected to a first signal. The second arithmetic unit is used to perform addition or subtraction operations on the data at the two input terminals. One input terminal of the third adder is connected to the output terminal of the register, the other input terminal is connected to the output terminal of the second arithmetic unit, and the output terminal is connected to the input terminal of the register.

Description

Technical Field

[0001] This disclosure relates to the field of display technology. More specifically, it relates to a distance calculation circuit and a grayscale compensation method. Background Technology

[0002] In the field of display technology, Local Dimming (LD) is an effective means of improving image contrast and color performance. It adjusts the brightness of each backlight zone according to the actual needs of the displayed content. In LD technology, pixel grayscale compensation is a crucial step. To achieve high-precision compensation of the grayscale of a specific pixel, the Point Spread Function (PSF) calculation is required. The PSF calculation uses the distance between the pixel and adjacent backlight zones.

[0003] In related technologies, multipliers are used to calculate the distance between pixels and adjacent backlight areas, which consumes a lot of hardware resources. Moreover, excessive multiplication operations will significantly reduce the maximum operating frequency of the LD module, thereby affecting the performance and response speed of the entire display system. Summary of the Invention

[0004] The purpose of this disclosure is to provide a distance calculation circuit and a grayscale compensation method to solve at least one of the above-mentioned technical problems.

[0005] To achieve the above objectives, the present disclosure adopts the following technical solution:

[0006] The first aspect of this disclosure provides a distance calculation circuit, including a distance calculation module. The distance calculation module is used to calculate the square of the distance between the current pixel and a target backlight partition in the target direction. The target backlight partition is any neighboring backlight partition of the current pixel. The target direction is a horizontal direction or a vertical direction. The distance calculation module includes a first arithmetic unit, a shifter, a second arithmetic unit, a third adder, and a register.

[0007] The first arithmetic unit includes two input terminals. One input terminal is used to input the coordinates of the target pixel in the current backlight partition in the target direction, and the other input terminal is used to input the distance between the current backlight partition and the target backlight partition in the target direction. The target pixel is the pixel adjacent to the current pixel, and the current backlight partition is the backlight partition where the current pixel is located. The first arithmetic unit is used to perform addition or subtraction operations on the signals input from the two input terminals to obtain a first distance value.

[0008] The input terminal of the shifter is connected to the output terminal of the first arithmetic unit. The shifter is used to shift the first distance value to obtain a second distance value, which is twice the first distance value.

[0009] The second arithmetic unit includes two input terminals, one of which is connected to the output terminal of the shifter, and the other input terminal is connected to a first signal, wherein the first signal is a first value. The second arithmetic unit is used to perform addition or subtraction operations on the data at the two input terminals.

[0010] The third adder includes two input terminals, one of which is connected to the output terminal of the register, and the other input terminal is connected to the output terminal of the second arithmetic unit. The output terminal of the third adder is connected to the input terminal of the register.

[0011] Optionally, the distance calculation module further includes a first multiplexer, which includes a first input terminal, a second input terminal, a control terminal, and an output terminal. The first input terminal is connected to a second signal, the second input terminal is connected to the output terminal of the register, the control terminal is connected to a first control signal, and one of the input terminals of the third adder is connected to the output terminal of the first multiplexer. The first multiplexer controls the output terminal to output the signal input by the first input terminal when the first control signal is at a first level, and controls the output terminal to output the signal input by the second input terminal when the first control signal is at a second level. The second signal is the squared distance between the current backlight partition and the target backlight partition in the target direction. The first control signal is at a first level when the current pixel crosses a backlight partition and at a second level when the current pixel does not cross a backlight partition.

[0012] Optionally, the distance calculation module further includes:

[0013] The first cross-zone recognition unit has its input end connected to the pixel data and its output end connected to the control end of the first multiplexer. It is used to identify whether the current pixel point crosses the backlight zone and output the first control signal to the first multiplexer according to the recognition result. The pixel data represents the pixel data of the current pixel point.

[0014] Optionally, the first cross-zone identification unit includes a rising edge detection unit and an OR gate. The rising edge detection unit includes a flip-flop and an AND gate. The flip-flop includes a data input terminal, a clock signal input terminal, and a main output terminal. The data input terminal is used to input pixel data, and the clock signal input terminal is used to input a clock signal. The main output terminal is connected to one input terminal of the AND gate, and the other input terminal of the AND gate is connected to a third signal. The output terminal of the AND gate is connected to one input terminal of the OR gate, and the other input terminal of the OR gate is connected to the third signal. The output terminal of the OR gate outputs the first control signal to the first multiplexer. When the third signal is at a first level, it indicates that the current pixel crosses a backlight zone; when the third signal is at a second level, it indicates that the current pixel does not cross a backlight zone.

[0015] Optionally, the neighborhood backlight partition of the current pixel includes multiple columns of backlight partitions distributed along the horizontal direction. The backlight partition in the column where the current backlight partition is located is divided into two sub-columns of backlight partitions. The distance calculation circuit includes a horizontal distance calculation circuit, which includes multiple distance calculation modules. Each distance calculation module corresponds to a column of backlight partitions or a column of sub-backlight partitions. In the distance calculation module corresponding to the column of backlight partitions on the first side of the current backlight partition, the first and second operators are adders. In the distance calculation module corresponding to the column of backlight partitions on the second side of the current backlight partition, the first and second operators are subtractors. In the distance calculation module corresponding to the column of sub-backlight partitions on the first side of the vertical center line of the current backlight partition, the first operator is a subtractor and the second operator is a subtractor. In the distance calculation module corresponding to the column of sub-backlight partitions on the second side of the vertical center line of the current backlight partition, the first operator is a subtractor and the second operator is an adder.

[0016] Optionally, the neighborhood backlight partition of the current pixel includes multiple rows of backlight partitions distributed along the vertical direction. The backlight partition of the row where the current backlight partition is located is divided into two rows of sub-backlight partitions. The distance calculation circuit includes a vertical distance calculation circuit, which includes multiple distance calculation modules. Each distance calculation module corresponds to a row of backlight partitions or a row of sub-backlight partitions. In the distance calculation module corresponding to the row of backlight partitions on the first side of the current backlight partition, the first and second operators are adders. In the distance calculation module corresponding to the row of backlight partitions on the second side of the current backlight partition, the first and second operators are subtractors. In the distance calculation module corresponding to the row of sub-backlight partitions on the first side of the horizontal center line of the current backlight partition, the first operator is a subtractor and the second operator is a subtractor. In the distance calculation module corresponding to the row of sub-backlight partitions on the second side of the horizontal center line of the current backlight partition, the first operator is a subtractor and the second operator is an adder.

[0017] Optionally, the neighborhood backlight partition of the current pixel includes multiple rows of backlight partitions distributed along the vertical direction. The backlight partition in the row where the current backlight partition is located is divided into two rows of sub-backlight partitions. The distance calculation circuit includes a vertical distance calculation circuit, which includes the distance calculation module and a time-division multiplexing control module. The first arithmetic unit includes a first adder and a first subtractor, and the second arithmetic unit includes a second adder and a second subtractor. The time-division multiplexing control module is used to control the distance calculation module to calculate the squared distance between the current pixel and each row of backlight partitions and each row of sub-backlight partitions in the vertical direction in a time-division multiplexing manner. When the squared distance between the current pixel and the row backlight partition on the first side of the current backlight partition is calculated, the first adder and the second adder are selected. When the time-division multiplexing control module controls the distance calculation module to calculate the squared distance between the current pixel and the row backlight partition on the second side of the current backlight partition, the first subtractor and the second subtractor are selected. When the time-division multiplexing control module controls the distance calculation module to calculate the squared distance between the current pixel and the row backlight partition where the current backlight partition is located, the first subtractor and the second subtractor are selected when the current pixel is located on the first side of the horizontal center line of the current backlight partition, and the first subtractor and the second adder are selected when the current pixel is located on the second side of the horizontal center line of the current backlight partition.

[0018] Optionally, the time-division multiplexing control module includes:

[0019] The second cross-zone recognition unit has its input terminal connected to the pixel data and is used to identify whether the current pixel point crosses the backlight zone. Based on the recognition result, it generates a second control signal and outputs it to the shift control unit.

[0020] A shift control unit, comprising multiple cascaded flip-flops, including a clock signal input terminal and a data input terminal, wherein the clock signal input terminal is connected to a clock signal, and the data input terminal is connected to the output terminal of the second cross-region identification unit, and the output terminal of each of the multiple cascaded flip-flops forms a third control signal;

[0021] A multiplexer unit, comprising a second multiplexer and a third multiplexer, wherein the second multiplexer is used to select one signal from a plurality of second signals and output it to the second input terminal of the first multiplexer; the second multiplexer is also used to select one signal from a plurality of fourth signals and output it to the other input terminal of the first arithmetic unit; the fourth signal represents the distance between the current backlight zone and the target backlight zone in the vertical direction; and the control terminals of the second and third multiplexers are connected to the third control signal.

[0022] The shift register unit includes multiple cascaded registers, each register corresponding to a row of backlight partitions, used to store the squared distance between the current pixel and the corresponding row of backlight partitions in the vertical direction.

[0023] Optionally, the distance calculation circuit further includes multiple fourth adders. For any fourth adder, the fourth adder includes a first input terminal and a second input terminal. The first input terminal is connected to the output terminal of a distance calculation module in the horizontal distance calculation circuit, and the second input terminal is connected to the output terminal of a register in the shift register unit.

[0024] Optionally, the first value is the square of the second value, where the second value is the number of data channels when the display panel transmits data.

[0025] The second aspect of this disclosure provides a grayscale compensation method, comprising the following steps:

[0026] Get the pixel data of the current pixel;

[0027] The pixel data is input to the distance calculation circuit to obtain the sum of squared distances between the current pixel and any neighboring backlight partition in the horizontal and vertical directions;

[0028] The grayscale compensation value of the current pixel is calculated based on the sum of squared distances.

[0029] The beneficial effects of this disclosure are as follows:

[0030] The distance calculation circuit of this embodiment can calculate the squared distance between the current pixel and any adjacent backlight zone in the horizontal or vertical direction through a first arithmetic unit, a shifter, a second arithmetic unit, a third adder, and a register. It uses addition / subtraction of small operands, shift operations, and simple logic control to realize the distance squared operation, avoiding the use of multipliers, thereby reducing resource consumption, improving calculation efficiency, and helping to increase the maximum operating frequency of the LD module. Attached Figure Description

[0031] The specific embodiments of this disclosure will be described in further detail below with reference to the accompanying drawings.

[0032] Figure 1 A schematic diagram of a 5*5 neighborhood backlight partition provided in an embodiment of this disclosure;

[0033] Figure 2 This is a schematic diagram showing the relationship between the horizontal distance between two adjacent pixels in the same row and any adjacent backlight partition Wmn.

[0034] Figure 3This is a schematic diagram showing the relationship between the vertical distance between two adjacent pixels in the same column and any adjacent backlight partition Wmn;

[0035] Figure 4 A schematic diagram of the overall architecture of an embodiment of the distance calculation circuit provided in this disclosure;

[0036] Figure 5 A schematic diagram of the overall architecture of another embodiment of the distance calculation circuit provided in this disclosure;

[0037] Figure 6 This is a circuit diagram of the distance calculation module in the horizontal distance calculation circuit;

[0038] Figure 7 This is a circuit diagram of the distance calculation module in the vertical distance calculation circuit;

[0039] Figure 8 This is a circuit diagram of the time-division multiplexing control module in the vertical distance calculation circuit;

[0040] Figure 9 This is a schematic diagram of the output result of the distance calculation module in the horizontal distance calculation circuit in the 4lane mode provided in the embodiments of this disclosure. Detailed Implementation

[0041] To make the objectives, technical solutions, and advantages of the embodiments of this disclosure clearer, the technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this disclosure. All other embodiments obtained by those skilled in the art based on the described embodiments of this disclosure without creative effort are within the scope of protection of this disclosure.

[0042] Unless otherwise defined, the technical or scientific terms used in this disclosure shall have the ordinary meaning understood by one of ordinary skill in the art to which this disclosure pertains. The terms “first,” “second,” and similar terms used in this disclosure do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Similarly, the terms “an,” “a,” or “the,” and similar terms do not indicate a quantity limitation, but rather indicate the presence of at least one. The terms “including,” “comprising,” or “containing,” and similar terms mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. The terms “connected,” “linked,” or similar terms are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. The terms “upper,” “lower,” “left,” and “right,” etc., are used only to indicate relative positional relationships, and these relative positional relationships may change accordingly when the absolute position of the described objects changes.

[0043] In Local Dimming (LD) functionality, pixel grayscale compensation is a crucial step that directly affects the final display effect. The core of grayscale compensation lies in precisely adjusting the grayscale value of a pixel based on the relative distance between the pixel and adjacent backlight zones, i.e., the influence of the Point Spread Function (PSF). This relative distance typically refers to the square root of the sum of the squares of the distances between the pixel and the backlight zone in both the horizontal (H) and vertical (V) directions, used to quantify the spatial relationship between the pixel and the backlight zone.

[0044] The adjacent backlight partitions of a certain pixel can adopt 3*3 neighborhood backlighting, 5*5 neighborhood backlighting, 7*7 neighborhood backlighting, 9*9 neighborhood backlighting, 11*11 neighborhood backlighting, etc. Please refer to [the relevant documentation]. Figure 1 , Figure 1 This is a schematic diagram of a 5x5 neighborhood backlight partition, as shown below. Figure 1 As shown, the neighborhood backlight partitions of a certain pixel P include 24 adjacent backlight partitions centered on the backlight partition W22 where pixel P is located, denoted as W00, W01, W02, W03, W04, W10, W11, W12, W13, W14, W20, W21, W23, W24, W30, W31, W32, W33, W34, W40, W41, W42, W43, and W44. When performing grayscale compensation or backlight value calculation on pixel P, it is necessary to calculate the relative distances between pixel P and the 24 adjacent backlight partitions. Figure 1 Taking backlight partition W00 as an example, the square of the relative distance s between pixel P and backlight partition W00 is expressed as s. 2 =h 2 +v2 , where h is the horizontal distance between pixel P and backlight partition W00, v is the vertical distance between pixel P and backlight partition W00, and (x, y) represents the coordinates of pixel P within backlight partition W22.

[0045] Traditional methods primarily use multipliers and adders to calculate the squared distances mentioned above. Specifically, multipliers are first used to calculate the squared distances between pixel P and its neighboring backlight zones in the horizontal direction (H) and vertical direction (V), respectively. Then, adders are used to sum these two squared values, and finally, a square root operation is performed to obtain the final relative distance. However, considering the extensive nature of the backlight neighborhood, for example, for a 5x5 neighborhood backlight, for each pixel P, the relative distances between pixel P and the surrounding 24 backlight zones need to be calculated, requiring 48 multipliers. Multipliers have disadvantages such as large circuit resource requirements and low circuit operation frequency. Excessive multiplication operations will reduce the maximum operating frequency of the LD function, which is not conducive to hardware implementation.

[0046] To address the aforementioned technical problems, this disclosure proposes a novel distance calculation circuit. Its core is to utilize small operand addition / subtraction, shift operations, and simple logic control to perform distance squared calculations, avoiding the use of multipliers, thereby reducing resource consumption and improving computational efficiency.

[0047] The basic principle employed by the distance calculation circuit in this embodiment can be found in [reference]. Figure 2 and Figure 3 .

[0048] Figure 2 This diagram illustrates the horizontal distance between two pixels with the same vertical coordinate (V) and adjacent pixels in the horizontal direction, and any adjacent backlight partition (Wmn). Here, m represents the m-th pixel in the vertical direction (V), and n represents the n-th pixel in the horizontal direction (H). Figure 2 As shown in the display panel, for two adjacent pixels P in a certain row i With P i+1 The i-th pixel P i The relative distance to the backlight partition Wmn is denoted as S_Q mn The i-th pixel P i The relative distance between the backlight partition Wmn and the backlight partition Wmn in the horizontal direction H is denoted as d_h. n The relative distance in the vertical direction V is represented by d_v m The (i+1)th pixel P i+1 The relative distance to the backlight zone Wmn is denoted as S_Q' mn The (i+1)th pixel P i+1 The relative distance between the backlight partition Wmn and the backlight partition Wmn in the horizontal direction H is denoted as d_h'.n Then the following condition is met:

[0049] (S_Q mn ) 2 =(d_h n ) 2 +(d_v m ) 2 (Equation 1.1)

[0050] (S_Q mn ') 2 =(d_h n +1) 2 +(d_v m ) 2 (Equation 1.2)

[0051] If pixel P i+1 Compared with the previous pixel P i The distance in the horizontal direction H is 1, which is d_h' n =d_h n +1, then the following condition is met:

[0052] (d_h n ') 2 =(d_h n +1) 2 (Equation 1.3)

[0053] (d_h n ') 2 =(d_h n ) 2 +2*d_h n +1 (Equation 1.4)

[0054] That is, for two adjacent pixels P in a certain row i With P i+1 Pixel P i+1 The squared distance in the horizontal direction H between the backlight partition Wmn and the backlight partition can be obtained through the preceding pixel P. i The compensation component is obtained by adding the square of the horizontal distance H between the backlight partition Wmn and the backlight partition Wmn, where the compensation component is:

[0055] 2*d_h n +1 (Equation 1.5)

[0056] Specifically, for the first pixel P0 in a certain row of the current backlight partition W22, the positional relationship between pixel P0 and the backlight partition Wmn satisfies:

[0057] d_h n =DIS_H n +1 (Equation 1.6)

[0058] (d_h n ) 2 =(DSI_H n ) 2 +2*(DIS_H n )+1(Equation 1.7)

[0059] Among them, DIS_H n This represents the horizontal distance between backlight partitions W22 and Wmn, which is the squared distance between the first pixel P0 in a row corresponding to the current backlight partition W22 and Wmn. It can be based on (DIS_H n ) 2 The compensation component is added to obtain the result, where the compensation component is 2*(DSI_H). n )+1.

[0060] It is understandable that, for the first pixel P0 in a certain row, assuming that the first pixel P0 is set to be located on the boundary line of the backlight partition W22, it can also be understood that the distance between the first pixel P0 and Wmn is DIS_H. n The second and subsequent pixels can be calculated using the squared distance from the first pixel plus a compensation component.

[0061] It should be noted that in the display panel, pixel data is transmitted row by row and column by column. Within each row, pixel data is transmitted sequentially from left to right. Therefore, for a 5x5 neighborhood backlight zone, assuming all backlight zones are divided into two areas by the vertical center line L1: the first area to the left of L1 and the second area to the right of L1, then for any backlight zone Wmn... ， Any two adjacent pixels P i With P i+1 The horizontal distance d_h between the backlight partition Wmn and the backlight partition n With d'_h n The relationship between them includes two scenarios:

[0062] (1) If the backlight partition Wmn is located in the first region, then pixel P i+1 The horizontal distance between pixel P and the backlight partition Wmn gradually increases as pixel data is transmitted, that is, the distance between pixel P and the backlight partition Wmn increases gradually as pixel data is transmitted. i+1 The horizontal distance between the backlight partition Wmn and the pixel P is greater than that between the two pixels. i The horizontal distance between the backlight zone Wmn and the backlight zone satisfies the formulas (1.3) and (1.4) shown above;

[0063] (2) If the backlight partition Wmn is located in the second region, then pixel P i+1The horizontal distance between pixel P and the backlight partition Wmn gradually decreases as pixel data is transmitted, that is, pixel P... i+1 The horizontal distance between the backlight partition Wmn and the pixel P is less than that of the backlight partition Wmn. i The horizontal distance between the backlight zone Wmn and the backlight zone Wmn satisfies the following formula:

[0064] (d_h n ') 2 =(d_h n -1) 2 (Equation 1.8)

[0065] (d_h n ') 2 =(d_h n ) 2 -2*(d_h n )+1(Equation 1.9)

[0066] Similarly, please refer to Figure 3 , Figure 3 This diagram illustrates the vertical distance between two adjacent pixels with the same horizontal H coordinate and any backlight partition Wmn, where m represents the m-th backlight partition Wmn in the vertical V direction, and n represents the n-th backlight partition Wmn in the horizontal H direction. Figure 3 As shown in the display panel, for two adjacent pixels P in a certain column j With P j+1 Assume the j-th pixel is P j The distance between the backlight partition Wmn and the backlight partition Wmn in the vertical direction V is denoted as d_v. m The (j+1)th pixel P j+1 The distance between the backlight partition Wmn and the backlight partition Wmn in the vertical direction V is denoted as d_v'. m Then, the following relationship can be derived in sequence:

[0067] For the backlight zones above the horizontal center line L2, such as W1n and W2n, where n = 0, 1, 2, 3 or 4, the following conditions must be met:

[0068] (d_v m ') 2 =(d_v m +1) 2 (Equation 2.1)

[0069] (d_v m ') 2 =(d_v m ) 2 +2*(d_v m )+1(Equation 2.2)

[0070] That is, for two adjacent pixels P in a certain column j With P j+1 Pixel P j+1 The square of the vertical distance V between the backlight partition Wmn and the backlight partition can be obtained through the preceding pixel P. j The compensation component is obtained by adding the square of the distance between the backlight zone Wmn and the point Wmn in the vertical direction V, where the compensation component is:

[0071] 2*(d_v m )+1(Equation 2.3)

[0072] Specifically, for the first pixel P0 in a certain column of the current backlight partition W22, the positional relationship between pixel P0 and the backlight partition Wmn satisfies:

[0073] d_v m =DIS_V m +1 (Equation 2.4)

[0074] (d_v m ) 2 =(DSI_V m ) 2 +2*(DIS_V m )+1(Equation 2.5)

[0075] Among them, DIS_V m The vertical distance between backlight partition W22 and backlight partition Wmn, that is, the squared distance between the first pixel P0 in a column corresponding to the current backlight partition W22 and Wmn, can be based on (DIS_V m ) 2 The result is obtained by adding the compensation component, where the compensation component is 2*(DSI_V). m +1. Similarly, for the first pixel P0 in a column, assuming that the first pixel P0 is located on the boundary line of the backlight partition W22, it can also be understood that the distance between the first pixel P0 and Wmn is DIS_V. m The second and subsequent pixels can be calculated using the squared distance from the first pixel plus a compensation component.

[0076] Similarly, for the backlight zones below the horizontal center line L2, such as W3n and W4n, the following condition holds:

[0077] (d_v m ') 2 =(d_v m -1) 2 (Equation 2.6)

[0078] (d_v m ')2 =(d_v m ) 2 -2*(d_v m )+1(Equation 2.7)

[0079] In summary, the squared distance between the current pixel and any adjacent backlight partition Wmn, whether in the horizontal direction H or the vertical direction V, has the logical iterative relationship shown in Equations 1.3, 1.4, 1.8, and 1.9 above. During the transmission of pixel data, the sum of squares can be obtained by using this iterative relationship to perform operations on the two components in the horizontal direction H and the vertical direction V and then adding them together. This iterative relationship only involves two operations: addition or subtraction and shifting. Combined with relatively simple control logic, complex sum of squares operations can be achieved, thus avoiding multiplication operations that consume a lot of resources.

[0080] Please refer to Figure 4 and Figure 5 , Figure 4 This is a schematic diagram of the overall architecture of an embodiment of the distance calculation circuit provided in this disclosure. Figure 5 This is a schematic diagram of the overall architecture of another embodiment of the distance calculation circuit provided in this disclosure. Figure 4 and Figure 5 The distance calculation circuit is used to calculate the sum of squares of the distances between the current pixel and the target backlight partition Wmn, where the target backlight partition Wmn is any neighboring backlight partition of the current pixel, and the current pixel is the pixel to be displayed transmitted through the data channel at the current moment. The distance between the current pixel and the target backlight partition Wmn can be represented by the square root of the sum of the squares of the horizontal and vertical distances. Therefore, the distance calculation circuit needs to include a horizontal distance calculation circuit 110 and a vertical distance calculation circuit 120. The horizontal distance calculation circuit 110 is used to calculate the square of the horizontal distance between the current pixel and the target backlight partition Wmn, and the vertical distance calculation circuit 120 is used to calculate the square of the vertical distance between the current pixel and the target backlight partition Wmn.

[0081] In both the horizontal and vertical directions, the principle of using small operand addition / subtraction, shift operations, and simple logic control to implement the distance square operation is the same. In this embodiment, the circuit unit that implements the distance square operation is represented as the distance operation module 20. The distance operation module 20 is used to calculate the square of the distance between the current pixel and the target backlight partition Wmn in the target direction, which is either horizontal or vertical, and the target backlight partition Wmn is any neighboring backlight partition of the current pixel.

[0082] Specifically, when the distance calculation module 20 is applied to the horizontal distance calculation circuit 110, the distance calculation module 20 is used to calculate the square of the horizontal distance between the current pixel and the target backlight partition Wmn. When the distance calculation module 20 is applied to the vertical distance calculation circuit 120, the distance calculation module 20 is used to calculate the square of the vertical distance between the current pixel and the target backlight partition Wmn.

[0083] The following is combined Figures 6 to 8 The circuit schematic of the distance calculation module is introduced, in which, Figure 6 This is a schematic diagram of the circuit structure of the distance calculation module in the horizontal direction. Figure 7 This is a schematic diagram of the circuit structure of the distance calculation module in the vertical direction. Figure 8 This is a schematic diagram of the circuit structure of the time-division multiplexing control module.

[0084] like Figure 6 and Figure 7 As shown, the distance calculation module 20 includes a first arithmetic unit U1, a shifter S, a second arithmetic unit U2, a third adder Add2, and a register R.

[0085] The first arithmetic unit U1 includes two input terminals. One input terminal inputs the coordinates of the target pixel in the current backlight partition in the target direction, and the other input terminal inputs the distance between the current backlight partition and the target backlight partition Wmn in the target direction. The target pixel is the pixel adjacent to the current pixel, and the current backlight partition is the backlight partition where the current pixel is located. The first arithmetic unit U1 is used to perform addition or subtraction operations on the signals input from the two input terminals to obtain a first distance value, which is also the distance between the target pixel and the target backlight partition in the target direction.

[0086] The input of shifter S is connected to the output of the first arithmetic unit U1. The shifter S is used to shift the first distance value to obtain a second distance value, which is twice the first distance value.

[0087] The second arithmetic unit U2 includes two input terminals, one of which is connected to the output terminal of the shifter S, and the other input terminal is connected to a first signal, which is a first value. The second arithmetic unit Add1 is used to perform addition or subtraction operations on the data at the two input terminals.

[0088] The third adder Add2 includes two input terminals, one of which is connected to the output terminal of register R, and the other input terminal is connected to the output terminal of the second arithmetic unit U2. The output terminal of the third adder Add2 is connected to the input terminal of register R. The output of the third adder Add2 is the square of the distance between the current pixel and the target backlight partition in the target direction.

[0089] Compared with related technologies, the distance calculation circuit of this disclosure embodiment, through a first arithmetic unit, a shifter, a second arithmetic unit, a third adder, and a register, can calculate the squared distance between the current pixel and any adjacent backlight partition in the horizontal or vertical direction. It uses addition / subtraction of small operands, shift operations, and simple logic control to realize the calculation of the squared distance, avoiding the use of multipliers, thereby reducing resource consumption, improving calculation efficiency, and contributing to the improvement of the maximum operating frequency.

[0090] Optional, such as Figures 6 to 7 As shown, the distance calculation module 20 also includes a first multiplexer Mux, which is represented as Mux-h in the horizontal distance calculation circuit 110 and as Mux-v in the vertical distance calculation circuit 120.

[0091] The first multiplexer Mux includes a first input terminal, a second input terminal, a control terminal, and an output terminal. The first input terminal is connected to a second signal, the second input terminal is connected to the output terminal of the register R, the control terminal is connected to a first control signal, and one of the input terminals of the third adder Add2 is connected to the output terminal of the first multiplexer Mux. The first multiplexer Mux controls the output terminal to output the signal input by the first input terminal when the first control signal is at a first level, and controls the output terminal to output the signal input by the second input terminal when the first control signal is at a second level. The second signal is the square of the distance between the current backlight partition and the target backlight partition in the target direction. The first control signal is at a first level when the current pixel crosses a backlight partition and at a second level when the current pixel does not cross a backlight partition.

[0092] Specifically, such as Figure 6 As shown, when the distance calculation module 20 calculates the horizontal distance (i.e., the vertical distance in the horizontal direction) between the current pixel and the target backlight partition Wmn, it is assumed that the current pixel is represented as P. i+1 The target pixel is represented as P. i In the input signals of the first arithmetic unit U1, cnt_h i Represents the target pixel P i The horizontal coordinate x and distance_h within the current backlight partitioni cnt_h represents the horizontal distance H between the current backlight partition and the target backlight partition Wmn. i With distance_h i The sum or difference can be expressed as d_h i d_h i That is, the target pixel P i The distance between the current backlight partition W22 and the target backlight partition Wmn in the horizontal direction H. Specifically, the distance between the current backlight partition and the target backlight partition Wmn in the horizontal direction H can be expressed as: the horizontal distance between the left boundary line of the current backlight partition W22 and the center point of the target backlight partition Wmn.

[0093] For example, please refer to Figure 1 and Figure 2 For a 5x5 neighborhood backlight partition, and the current backlight partition is W22, then:

[0094] For the first target backlight partition Wm0, the horizontal distance H between the current backlight partition W22 and the target backlight partition Wmn is 1.5*L, which is distance_h. i =1.5*L, where L represents the length of each backlight partition in the horizontal direction H in the neighboring backlight partition. When calculating the horizontal distance between the current backlight partition and the first target backlight partition Wm0, the first arithmetic unit U1 is an adder, and its output is x+1.5*L.

[0095] For the second target backlight partition Wm1, the horizontal distance H between the current backlight partition W22 and the target backlight partition Wmn is 0.5*L, which is distance_h. i =0.5*L. When calculating the horizontal distance between the current backlight partition and the target backlight partition Wm1 in the second column, the first arithmetic unit U1 is an adder, and its output is x+0.5*L.

[0096] For the fourth target backlight partition Wm3, the horizontal distance H between the current backlight partition W22 and the target backlight partition Wmn is 1.5*L, which is distance_h. i =1.5*L, when calculating the horizontal distance between the current backlight partition and the target backlight partition Wm1 in the second column, the first arithmetic unit U1 is a subtractor, and its output is 1.5*Lx;

[0097] For the fifth target backlight partition Wm4, the horizontal distance H between the current backlight partition W22 and the target backlight partition Wmn is 2.5*L, which is distance_h. i=1.5*L, when calculating the horizontal distance between the current backlight partition and the target backlight partition Wm1 in the second column, the first arithmetic unit U1 is a subtractor, and its output is 2.5*Lx;

[0098] For the third column of target backlight partition Wm2, when target pixel P i When located to the left of the vertical center line L1, the distance between the current backlight partition W22 and the target backlight partition Wmn in the horizontal direction H is 0.5*L. The first arithmetic unit U1 is a subtractor, and its output is 0.5*Lx; when the target pixel P i When located to the right of the vertical center line L1, the distance between the current backlight partition W22 and the target backlight partition Wmn in the horizontal direction H is 0.5*L. The first arithmetic unit U1 is a subtractor, and its output is x-0.5*L.

[0099] After the addition and OR operation by the first arithmetic unit U1, the first distance value is represented as d_h. i That is, the target pixel P i The horizontal distance from the target backlight zone Wmn. For example, such as... Figure 3 As shown, for the first column of target backlight partitions, the target pixel P i Its horizontal distance d_h i =1.5*L+x.

[0100] In this embodiment of the disclosure, the first distance value is a binary number. Shifter S is used to shift the first distance value one bit to the left, which means multiplying the first distance value by 2; that is, the output of shifter S is 2*(d_h). i ).

[0101] The second arithmetic unit U2 can perform addition or subtraction operations. One of the two input signals of the second arithmetic unit U2 is 2*(d_h). i The other is the first value, const_data_h.

[0102] Here, the first value, `const_data_h`, is a fixed value related to the data transmission mode of the display panel. Specifically, the first value `const_data_h` is the square of the second value `b`, where the second value `b` is the number of data channels when the display panel transmits data. For example, for a display panel in 1-lane mode, one pixel is transmitted at a time, that is, the current pixel P... i+1 The distance between the current pixel and the previous pixel (i.e., the pixel transmitted in the previous moment) is 1 pixel. At this time, const_data_h = 1. For a 2-lane display panel, 2 pixels are transmitted each time, meaning that the current pixel P is currently... i+1The distance between the current pixel and the preceding pixel is 2 pixels. In this case, `const_data_h = 4`. For a 4-lane display panel, 4 pixels are transmitted each time, meaning the current pixel P... i+1 The distance between the current pixel and the previous pixel is 4 pixels, const_data_h = 16, and so on.

[0103] In this embodiment, taking the 1lane mode as an example, the first value is a fixed value of 1. When the second arithmetic unit U2 performs addition, the output of the second arithmetic unit U2 is 1 + 2 * (d_h) i When the second arithmetic unit U2 performs a subtraction operation, the output of the second arithmetic unit U2 is 1 - 2 * (d_h). i ).

[0104] Of the two input signals of the third adder Add2, one is 1+2*(d_h) i ) or 1-2*(d_h i The other is the output of the first multiplexer Mux, where the output of the first multiplexer Mux is the target pixel P. i The square of the horizontal distance H between the target backlight partition Wmn and the target backlight partition, i.e. (d_h) i ) 2 Therefore, the output of the third adder Add2 is (d_h i ) 2 +2*(d_h i )+1 or (d_h i ) 2 -2*(d_h i )+1, that is, the output of the third adder Add2 is the current pixel P. i+1 The square of the horizontal distance H between the target backlight partition Wmn and the target backlight partition.

[0105] Specifically, such as Figure 6 As shown, the first multiplexer Mux-h is used to output the data from the first input terminal or the data from the second input terminal under the control of the first control signal. The data from the first input terminal is the second signal SQUAR_DIS_Hi, which represents the squared horizontal distance between the current backlight zone and the target backlight zone Wmn, i.e., distance_h. i The square of the second input is the output of register R.

[0106] For the distance calculation module 20, if the current pixel is the first pixel P0 in a row within the current backlight partition, the first control signal controls the first multiplexer Mux-h to output the second signal SQUAR_DIS_Hi. If the current pixel is not the first pixel in a row, for example, the second pixel P1, then the output of register R may be (d_h0). 2 +2*(d_h0)+1, which is also (d_h1) 2 This represents the square of the horizontal distance H between the second pixel P1 and the target backlight partition Wmn. At this time, the first control signal controls the signal of the output register R of the first multiplexer Mux-h. Similarly, the square of the horizontal distance H between each subsequent pixel and the target backlight partition Wmn can be obtained.

[0107] Wherein, the current pixel P i+1 Cross-backlight partition refers to the current pixel P in the horizontal direction H. i+1 It is a transition from one backlight partition to a new backlight partition, with the current pixel P. i+1 Not crossing backlight zones means that in the horizontal direction H, the current pixel P i+1 The target pixel is located in the same backlight partition. For example, in the horizontal direction, each backlight partition contains 100 pixels. Let's assume the pixels in backlight partition W22 are denoted as P. 0， P 1， P 2， P 3， ...P 99， The pixels within the backlight zone W23 include P 100， P 101， P 102， P 103 ...P 199 If the current pixel P i+1 For P 100 This indicates that the current pixel P i+1 Across backlight zones, if the current pixel P i+1 For P 99 This indicates that the current pixel P i+1 Pixels that do not cross backlight zones. For pixels that cross backlight zones, they can also be understood as boundary pixels within the backlight zone, or the first pixel of the backlight zone in the horizontal direction H. Therefore, the first control signal needs to be at the first level in this case, and conversely, the first control signal needs to be at the second level if the pixel does not cross backlight zones.

[0108] For the current backlight partition, the horizontal distance between its first pixel and any target backlight partition Wmn is represented as the horizontal distance H between the current backlight partition and the target backlight partition Wmn: distance_h iFor each pixel after the first pixel, the square of its horizontal distance H from the target backlight partition Wmn can be calculated using the square of the distance between the adjacent previous pixel and the target backlight partition Wmn, plus a compensation component. Therefore, the distance calculation module 20 needs to use different outputs for the first pixel and other pixels. In specific implementation, the first control signal and the first multiplexer Mux-h are used to select different outputs. When the first control signal is at the first level, the first multiplexer Mux-h is controlled to output the second signal SQUAR_DIS_Hi, which is a fixed value, namely distance_h. i The square of the first control signal, when the first control signal is at the second level, controls the output of the first multiplexer Mux (d_h). i ) 2 +2*(d_h i )+1 or (d_h i ) 2 +2*(d_h i )-1.

[0109] Similarly, such as Figure 7 As shown, when the distance calculation module 20 calculates the distance between the current pixel and the target backlight partition Wmn in the vertical direction V (that is, the vertical distance in the vertical direction), it is assumed that the current pixel is represented as P. j+1 The target pixel is represented as P. j In the input signals of the first arithmetic unit U1, cnt_v j Represents the target pixel P j The vertical coordinate y, distance_v within the current backlight partition j This indicates the distance in the vertical direction V between the current backlight partition and the target backlight partition Wmn. The first value const_data_v input to the second arithmetic unit U2 has the same meaning as the first value const_data_h. The second signal SQUAR_DIS_Vj represents the square of the distance in the vertical direction V between the current backlight partition and the target backlight partition Wmn. That is, the second signal SQUAR_DIS_Vj is a fixed value, which is distance_v. j The square of the first control signal input to the control terminal of the first multiplexer Mux-v is represented as edge-det_j. edge-det_j can be understood as a boundary detection signal. When edge-det_j is at the first level, it indicates that the current pixel is the first pixel in a column within the current backlight partition, crossing the backlight partition. In this case, the first multiplexer Mux-v outputs the second signal SQUAR_DIS_Vj. When edge-det_j is at the second level, it indicates that the current pixel does not cross the backlight partition, and the first multiplexer Mux-v outputs (d_v).j ) 2 +2*(d_v j )+1 or (d_v j ) 2 -2*(d_v j )+1.

[0110] In one possible implementation, the distance calculation module 20 further includes a first cross-zone identification unit 210. The input end of the first cross-zone identification unit 210 is connected to the pixel data, and the output end is connected to the control end of the first multiplexer Mux. It is used to identify whether the current pixel point crosses the backlight zone, and output the first control signal to the first multiplexer Mux according to the identification result. The pixel data represents the pixel data of the current pixel point.

[0111] Optional, such as Figure 6 As shown, the first cross-area identification unit 210 includes a rising edge detection unit and an OR gate. The rising edge detection unit includes a flip-flop DFF and an AND gate. The flip-flop DFF includes a data input terminal D, a clock signal input terminal, and a main output terminal Q. The data input terminal D is used to input the pixel data de_i of the current pixel. The clock signal input terminal is used to input the clock signal clk. The main output terminal Q is connected to one of the input terminals of the AND gate. The other input terminal of the AND gate is connected to the third signal lane_end_flag. The output terminal of the AND gate is connected to one of the input terminals of the OR gate. The other input terminal of the OR gate is connected to the third signal lane_end_flag. The output terminal of the OR gate outputs the first control signal to the first multiplexer Mux-h. When the third signal lane_end_flag is at a first level, it indicates that the current pixel crosses a row. When the third signal lane_end_flag is at a second level, it indicates that the current pixel does not cross a row.

[0112] In this embodiment of the disclosure, the first cross-region identification unit 210 is used to generate a first control signal.

[0113] Specifically, the DFF flip-flop is a D-type flip-flop. When the clock signal clk changes from low to high, if the data input terminal D is high, the main output terminal Q will follow D to go high; if D is low, the main output terminal Q will follow D to go low. When the clock signal clk goes low again, the main output terminal Q will retain its previous value. That is, the value of the main output terminal Q changes at the rising edge of each positive pulse cycle and remains unchanged until the next rising edge.

[0114] In this configuration, a high level for pixel data `de_i` indicates that the current pixel is valid, while a low level indicates that the current pixel is invalid. When pixel data `de_i` changes from low to high, the output of the AND gate is high, indicating that a new backlight zone has been entered. The third signal `lane_end_flag` indicates whether it is the last pixel of the current row. A high level for `lane_end_flag` indicates that a new row has been entered, meaning the current pixel is not in the same row as the previous pixel. If the current pixel spans rows, it is the first pixel in a row within the current backlight zone. A low level for `lane_end_flag` indicates that the current pixel does not span rows, meaning it is in the same row as the previous pixel.

[0115] In this embodiment of the disclosure, for the distance calculation module 20 in the horizontal distance calculation circuit 110, when the current pixel enters a new backlight partition or a new row, the first control signal is at the first level. At this time, the distance calculation module 20 outputs the second signal SQUAR_DIS_Hi to the output port squar_i of the distance calculation module 20, which is used for the square iteration calculation of the next adjacent pixel. In each subsequent clock cycle, the first multiplexer Mux-h selects the squared distance of the horizontal direction H obtained through the iteration calculation, that is, the data (d_h) of the register R. i ) 2 +2*(d_h i )+1 or (d_h i ) 2 -2*(d_h i )+1.

[0116] Similarly, for the distance calculation module 20 in the vertical distance calculation circuit 120, when the current pixel enters a new backlight partition, the first control signal is at the first level. At this time, the distance calculation module 20 outputs the second signal SQUAR_DIS_Vj to the output port squar_j of the distance calculation module 20, which is used for the square iteration calculation of the next adjacent pixel. In each subsequent clock cycle, the first multiplexer Mux-v selects the square of the vertical distance obtained through the iteration calculation, that is, the data (d_v) in register R. j ) 2 +2*(d_v j )+1 or (d_v j ) 2 -2*(d_v j )+1.

[0117] Optionally, the neighborhood backlight partition of the current pixel includes multiple columns of backlight partitions distributed horizontally and multiple rows of backlight partitions distributed vertically. The backlight partition in the column where the current backlight partition is located is divided into two columns of sub-backlight partitions, and the backlight partition in the row where the current backlight partition is located is divided into two rows of sub-backlight partitions. The backlight partition in the column where the current backlight partition is located is divided into two columns of sub-backlight partitions with the vertical center line L1 of the partition as the boundary, and the backlight partition in the row where the current backlight partition is located is divided into two rows of sub-backlight partitions with the horizontal center line L2 of the partition as the boundary.

[0118] For example, for a 5*5 neighborhood backlight partition, the neighborhood backlight partition of the current pixel includes 5 columns of backlight partitions distributed in the horizontal direction and 5 rows of backlight partitions distributed in the vertical direction. The third column of the backlight partition where the current backlight partition W22 is located is divided into two sub-backlight partitions by the vertical center line L1, and the third row of the backlight partition where the current backlight partition W22 is located is divided into two sub-backlight partitions by the horizontal center line L2.

[0119] Optionally, the horizontal distance calculation circuit 110 includes multiple distance calculation modules 20, each distance calculation module 20 corresponding to a column of backlight partitions or a column of sub-backlight partitions. The distance calculation module 20 is used to calculate the horizontal distance between the current pixel and the corresponding column of backlight partitions. In the distance calculation module corresponding to the column of backlight partitions on the first side of the current backlight partition, the first and second operators are adders. In the distance calculation module corresponding to the column of backlight partitions on the second side of the current backlight partition, the first and second operators are subtractors. In the distance calculation module corresponding to the column of sub-backlight partitions on the first side of the vertical center line of the current backlight partition, the first operator is a subtractor and the second operator is a subtractor. In the distance calculation module corresponding to the column of sub-backlight partitions on the second side of the vertical center line of the current backlight partition, the first operator is a subtractor and the second operator is an adder.

[0120] In each neighboring backlight partition, for backlight partitions in the same column, the horizontal distance between each backlight partition in that column and the current pixel is the same. Therefore, each column of backlight partitions can share a distance calculation module 20. For example, for a 5*5 neighboring backlight partition, the horizontal distance calculation circuit 110 includes six distance calculation modules 20. Assuming that from left to right, the distance calculation modules 20 corresponding to the six columns of backlight partitions or sub-backlight partitions are denoted as SQUAR-H0, SQUAR-H1, SQUAR-H21, SQUAR-H22, SQUAR-H3, and SQUAR-H4, respectively, SQUAR-H21 and SQUAR-H22 are used to calculate the horizontal distance between the current pixel and the column of backlight partitions where the current backlight partition is located. In each distance calculation module, the second signal SQUAR_DIS_Hi and the signal distance_h...i It may be different, as it is determined by the horizontal distance between each backlight partition and the current backlight partition W22.

[0121] according to Figure 3 and Figure 4 Assume the current pixel is represented as P. i+1 If the current backlight partition where it is located is W22, then for each neighboring backlight partition to the left of the current backlight partition W22, the current pixel P i+1 Compared to the horizontal distance of any neighboring backlight partition, the previous pixel P i The horizontal distance from the current backlight partition increases progressively, while for each neighboring backlight partition to the right of the current backlight partition W22, the current pixel P... i+1 Compared to the horizontal distance of any neighboring backlight partition, the previous pixel P i The horizontal distance to the backlight partition decreases progressively. Therefore, for the two backlight partitions on the left, the first arithmetic unit U1 and the second arithmetic unit U2 in the distance calculation module 20 are adders, that is, the first arithmetic unit U1 and the second arithmetic unit U2 in SQUAR-H0 and SQUAR-H1 are adders. For the two backlight partitions on the right, the first arithmetic unit U1 and the second arithmetic unit U2 in the distance calculation module 20 are subtractors, that is, the first arithmetic unit U1 and the second arithmetic unit U2 in SQUAR-H3 and SQUAR-H4 are subtractors. For the neighboring backlight partitions (such as W02, W12, W32, W42) in the column where the current backlight partition W22 is located, at the current pixel P... i+1 When located to the left of the vertical center line, the current pixel P i+1 Compared to the horizontal distance of the current column's neighboring backlight partitions, the previous pixel P i The horizontal distance from the backlight zone decreases, therefore the first arithmetic unit U1 is a subtractor, and the second arithmetic unit U2 is a subtractor; that is, in SQUAR-H21, the first arithmetic unit U1 is a subtractor, and the second arithmetic unit U2 is a subtractor; and the current pixel P i+1 When located to the right of the vertical center line, the current pixel P i+1 Compared to the horizontal distance of the current column's neighboring backlight partitions, the previous pixel P i The horizontal distance from the backlight zone increases progressively. Therefore, the first arithmetic unit U1 is a subtractor and the second arithmetic unit U2 is an adder. In other words, in SQUAR-H22, the first arithmetic unit U1 is a subtractor and the second arithmetic unit U2 is an adder.

[0122] Optionally, the vertical distance calculation circuit 120 includes multiple distance calculation modules 20, each distance calculation module 20 corresponding to a row of backlight partitions or a row of sub-backlight partitions. The distance calculation module 20 is used to calculate the distance between the current pixel and the corresponding row of backlight partitions or the corresponding row of sub-backlight partitions in the vertical direction. In the distance calculation module corresponding to the row of backlight partitions on the first side of the current backlight partition, the first and second operators are adders. In the distance calculation module corresponding to the row of backlight partitions on the second side of the current backlight partition, the first and second operators are subtractors. In the distance calculation module corresponding to the row of sub-backlight partitions on the first side of the horizontal center line of the current backlight partition, the first operator is a subtractor and the second operator is a subtractor. In the distance calculation module corresponding to the row of sub-backlight partitions on the second side of the horizontal center line of the current backlight partition, the first operator is a subtractor and the second operator is an adder.

[0123] In this context, for backlight partitions within the same row, the vertical distance between each backlight partition and the current pixel is the same. Therefore, each row of backlight partitions can share a single distance calculation module 20. For example, for a 5x5 neighborhood backlight partition, the vertical distance calculation circuit 120 includes six distance calculation modules 20. Assuming they are denoted as SQUAR-V0, SQUAR-V1, SQUAR-V21, SQUAR-V22, SQUAR-V3, and SQUAR-V4 from top to bottom, then in each distance calculation module, the second signal SQUAR_DIS_Vj and the signal distance_v... j It may be different, as it is determined by the vertical distance between each backlight zone and the current backlight zone W22.

[0124] according to Figure 3 and Figure 4 Assume the current pixel is represented as P. j+1 If the current backlight partition where it is located is W22, then for each neighboring backlight partition above the current backlight partition W22, the current pixel P j+1 Compared to the vertical distance of any backlight zone, the previous pixel P j The vertical distance from the current backlight partition increases progressively, while for each neighboring backlight partition below the current backlight partition W22, the current pixel P... j+1 Compared to the horizontal distance of any backlight zone, the previous pixel P jThe vertical distance to the backlight partition decreases. Therefore, for the two rows of backlight partitions above the current backlight partition W22, the first arithmetic unit U1 and the second arithmetic unit U2 in the distance calculation module 20 are adders. For the two rows of backlight partitions below the current backlight partition W22, the first arithmetic unit U1 and the second arithmetic unit U2 in the distance calculation module 20 are subtractors. For the neighboring backlight partitions (such as W20, W21, W23, and W24) in the row where the current backlight partition W22 is located, at the current pixel P... j+1 When located above the horizontal center line L2, the current pixel P j+1 Compared to the vertical distance of the current column's neighboring backlight partitions, the previous pixel P j The vertical distance from the backlight zone decreases, therefore the first arithmetic unit U1 is a subtractor, and the second arithmetic unit U2 is a subtractor; that is, in SQUAR-V21, the first arithmetic unit U1 is a subtractor, and the second arithmetic unit U2 is a subtractor; and the current pixel P j+1 When located below the horizontal center line L2, the current pixel P j+1 Compared to the vertical distance of the current column's neighboring backlight partitions, the previous pixel P j The vertical distance from the backlight zone increases progressively. Therefore, the first arithmetic unit U1 is a subtractor and the second arithmetic unit U2 is an adder. In other words, in SQUAR-V22, the first arithmetic unit U1 is a subtractor and the second arithmetic unit U2 is an adder.

[0125] In this embodiment of the disclosure, a distance calculation module 20 is set for each row of neighboring backlight partitions in the vertical direction V. The corresponding distance calculation module 20 simultaneously calculates the square of the distance between the current pixel and each row of target backlight partitions in the vertical direction. This setting can save the time spent on distance calculation, but it requires more hardware resources and is costly.

[0126] In one possible implementation, the vertical distance calculation circuit 120 includes the distance calculation module 20 and a time-division multiplexing control module 30. The first arithmetic unit U1 includes a first adder Add0 and a first subtractor Sub1, and the second arithmetic unit U2 includes a second adder Add1 and a second subtractor Sub2. The time-division multiplexing control module 30 is used to control the distance calculation module 20 to calculate the squared distance between the current pixel and each row of backlight partitions in the vertical direction in a time-division multiplexing manner. Specifically, when the time-division multiplexing control module 30 controls the distance calculation module 20 to calculate the squared distance between the current pixel and the row of backlight partitions on the first side of the current backlight partition, it selects the first adder Add0 and the second adder Sub2. When the time-division multiplexing control module 30 controls the distance calculation module 20 to calculate the squared distance between the current pixel and the row backlight partition on the second side of the current backlight partition, the first subtractor Sub1 and the second subtractor Sub2 are selected. When the time-division multiplexing control module 30 controls the distance calculation module 20 to calculate the squared distance between the current pixel and the row backlight partition where the current backlight partition is located, the first subtractor Sub1 and the second subtractor Sub2 are selected when the current pixel is located on the first side of the horizontal center line L2 of the current backlight partition, and the first subtractor Sub1 and the second adder Add1 are selected when the current pixel is located on the second side of the horizontal center line of the current backlight partition.

[0127] In this embodiment, the vertical distance calculation circuit 120 uses only one distance calculation module 20. The time-division multiplexing control module 30 controls this distance calculation module 20 to sequentially calculate the squared vertical distance between the current pixel and each row of backlight partitions. This configuration reduces hardware resource consumption; tasks that would normally require multiple distance calculation modules can be completed with a single time-division multiplexing circuit, resulting in high resource utilization and reduced hardware investment costs. However, the time-division calculation method increases processing time. In specific implementations, a suitable vertical distance calculation circuit can be selected based on actual needs, such as resource consumption and operating efficiency. This embodiment does not limit the selection of such a circuit.

[0128] In one possible implementation, such as Figure 5 and Figure 8 As shown, the time-division multiplexing control module 30 includes a second cross-zone identification unit 310, a shift control unit 320, a multiplexer unit 330, and a shift register 340.

[0129] The input terminal of the second cross-zone recognition unit 310 is connected to the pixel data de_j, and is used to identify whether the current pixel point crosses the backlight zone. Based on the recognition result, a second control signal is generated and output to the shift control unit 320.

[0130] For example, such as Figure 8 As shown, the second cross-region identification unit 310 includes a flip-flop DFF and an AND gate. The flip-flop DFF includes a data input terminal D, a clock signal input terminal, and a main output terminal Q. The data input terminal D is used to input the pixel data de_j of the current pixel point. The clock signal input terminal is used to input the clock signal clk. The main output terminal Q is connected to one of the input terminals of the AND gate, and the other input terminal of the AND gate is connected to the pixel data de_j. The output terminal of the AND gate is connected to the input terminal of the shift control unit 320.

[0131] The shift control unit 320 includes multiple cascaded flip-flops (DFFs). The shift control unit 320 includes a clock signal input terminal and a data input terminal. The clock signal input terminal is connected to the clock signal clk, and the data input terminal is connected to the output terminal of the second cross-zone identification unit 310. The output terminals of each flip-flop in the multiple cascaded flip-flops (DFFs) form a third control signal.

[0132] In this shift control unit 320, the number of triggers (DFFs) is the same as the number of rows of the neighboring backlight partitions in the vertical direction V. The shift control unit 320 is used to shift the second control signal. For example, as shown... Figure 8 As shown, for a 5*5 neighborhood backlight partition, the shift control unit 320 needs to include 5 flip-flops (DFFs), which together form a 5-bit third control signal. Each flip-flop DFF includes a clock signal input, a data input D, and a main output Q. The data input of the first flip-flop DFF is connected to the output of the AND gate in the second cross-zone identification unit 310, and the data inputs of the other flip-flops DFFs are connected to the main output Q of the previous flip-flop DFF. The clock signal inputs of each flip-flop DFF are connected to the clock signal clk. The third control signal can be generated by cascading multiple flip-flops DFFs.

[0133] The multiplexer unit 330 includes a second multiplexer Mux-va and a third multiplexer Mux-vb. The second multiplexer Mux-va is used to select one of the multiple second signals SQUAR_DIS_Vj and output it to the second input terminal of the first multiplexer Mux-v. The second multiplexer Mux-vb is used to select one of the multiple fourth signals distance_vj and output it to the other input terminal of the first arithmetic unit U1. The fourth signal distance_vj represents the distance between the current backlight zone and the target backlight zone in the vertical direction V. The control terminals of the second multiplexer Mux-va and the third multiplexer Mux-vb are connected to the output terminal of the shift control unit 320, that is, the third control signal.

[0134] like Figure 8 As shown, for a 5*5 neighborhood backlight partition, the multiple second signals SQUAR_DIS_Vj include 5 channels, assuming they are denoted as second signals SQUAR_DIS_V0, SQUAR_DIS_V1, SQUAR_DIS_V2, SQUAR_DIS_V3, and SQUAR_DIS_V4 respectively. SQUAR_DIS_V0 represents the squared distance in the vertical direction V between the current backlight partition and the first row target backlight partition W0n, and SQUAR_DIS_V1 represents the current backlight partition... SQUAR_DIS_V2 represents the squared distance in the vertical direction V between the current backlight partition and the target backlight partition in the third row, i.e., the backlight partition W2n in the row where the current backlight partition is located; SQUAR_DIS_V3 represents the squared distance in the vertical direction V between the current backlight partition and the target backlight partition W3n in the fourth row; and SQUAR_DIS_V4 represents the squared distance in the vertical direction V between the current backlight partition and the target backlight partition W4n in the fifth row.

[0135] Correspondingly, the multiplexed fourth signal distance_v j This includes 5 channels, assuming they are denoted as the fourth signal distance_v0, distance_v1, distance_v2, distance_v3, and distance_v4, respectively. Here, distance_v0 represents the distance in the vertical direction V between the current backlight partition and the first row target backlight partition W0n, distance_v1 represents the distance in the vertical direction V between the current backlight partition and the second row target backlight partition W1n, distance_v2 represents the distance in the vertical direction V between the current backlight partition and the third row target backlight partition W2n, distance_v3 represents the distance in the vertical direction V between the current backlight partition and the fourth row target backlight partition W3n, and distance_v4 represents the distance in the vertical direction V between the current backlight partition and the fifth row target backlight partition W4n.

[0136] The connection between the control terminals of the second multiplexer Mux-va and the third multiplexer Mux-vb and the output terminal of the shift control unit 320 can be understood as follows: The shift control unit 320 includes multiple cascaded flip-flops (DFFs). The main output terminal of each flip-flop DFF constitutes one bit of the output of the shift control unit 320, denoted as sel_j[m]. For the vertical distance calculation circuit 120 of the 5*5 neighborhood backlight, its shift control unit 320 includes 5 outputs, namely sel_j[0], sel_j[1], sel_j[2], sel_j[3], and sel_j[4]. These constitute a 5-bit gating signal sel_j (i.e., the third control signal). The gating signal sel_j is input to the control terminals of the second multiplexer Mux-va and the third multiplexer Mux-vb.

[0137] The control terminals of the second multiplexer Mux-va and the third multiplexer Mux-vb select the corresponding second signal SQUAR_DIS_Vj and fourth signal distance_vj based on the strobe signal sel_j. For example:

[0138] When sel_j = 5'b10000, it means that the vertical distance to the first row of backlight zones is calculated at this time. The second multiplexer Mux-va is selected: SUQAR_DIS_V0, and the third multiplexer Mux-vb is selected: distance_v0.

[0139] When sel_j = 5'b11000, it means that the vertical distance to the second row of backlight zones is calculated at this time. The second multiplexer Mux-va is selected: SUQAR_DIS_V1, and the third multiplexer Mux-vb is selected: distance_v1.

[0140] When sel_j = 5'b11100, it means that the vertical distance to the third row of backlight zones is calculated at this time. The second multiplexer Mux-va is selected: SUQAR_DIS_V2, and the third multiplexer Mux-vb is selected: distance_v2.

[0141] When sel_j = 5'b11110, it means that the vertical distance to the fourth row of backlight zones is calculated at this time. The second multiplexer Mux-va is selected: SUQAR_DIS_V3, and the third multiplexer Mux-vb is selected: distance_v3.

[0142] When sel_j = 5'b11111, it means that the vertical distance to the fifth row of backlight zones is calculated at this time. The second multiplexer Mux-va is selected: SUQAR_DIS_V4, and the third multiplexer Mux-vb is selected: distance_v4.

[0143] The shift register unit 340 includes multiple cascaded registers, each corresponding to a row of backlight partitions, used to store the squared vertical distance between the current pixel and the corresponding row of backlight partitions. Specifically, the shift register unit 340 is connected to the output of the distance calculation module 20 in the vertical distance calculation circuit 120, that is, connected to the output port square_j, and is used to shift and store the output of the distance calculation module 20. The number of registers in the shift register unit 340 is related to the number of rows of the neighboring backlight partitions in the vertical direction. For example, as shown... Figure 5 As shown, for a 5*5 neighborhood backlight partition, the shift register unit 340 includes 5 registers, denoted as Register_0, Register_1, Register_2, Register_3, and Register_4 respectively. The 5 registers correspond to 5 rows of target backlight partitions. Each register is used to store the square of the vertical distance between the corresponding row of target backlight partitions and the current pixel.

[0144] In one possible implementation, the distance calculation circuit further includes multiple fourth adders Add3. For any fourth adder Add3, the fourth adder Add3 includes a first input terminal and a second input terminal. The first input terminal is connected to the output terminal of a distance calculation module 20 in the horizontal distance calculation circuit 110, and the second input terminal is connected to the output terminal of a register in the vertical distance calculation circuit 120.

[0145] For example, please refer to Figure 5 For a 5*5 neighborhood backlight partition, the fourth adder Add3 includes three parts. One of them, the third adder Add3, is used to calculate the sum of squared distances between the current pixel and a target backlight partition. That is, among the two inputs of the third adder Add3, one is the squared distance between the current pixel and the target backlight partition in the horizontal direction H, and the other is the squared distance between the current pixel and the target backlight partition in the vertical direction V.

[0146] Please refer to Figure 9 , Figure 9This is a schematic diagram illustrating the output of the distance calculation module in the horizontal distance calculation circuit under 4-lane mode. In 4-lane mode, during pixel data transmission, four pixels are transmitted at a time. This means the distance between the current pixel and its preceding neighbor is four pixels. Therefore, the horizontal distance calculation circuit outputs the squared horizontal distance between four pixels and a neighboring backlight zone each clock cycle. Figure 9 As shown, the four squared distances output in the first clock cycle T1 are 24025, 24336, 24649, and 24964, respectively, and their square roots are 155, 156, 157, and 158. The four squared distances output in the second clock cycle T2 are 25281, 25600, 25921, and 26244, respectively, and their square roots are 159, 160, 161, and 162. In each subsequent clock cycle, the squared distances of four pixels to the same neighboring backlight zones in the horizontal direction are output.

[0147] Based on the same inventive concept, a second aspect of this disclosure provides a grayscale compensation method, comprising the following steps:

[0148] Step S101: Obtain the pixel data of the current pixel;

[0149] Step S102: Input the pixel data into the distance calculation circuit to obtain the sum of squared distances between the current pixel and any neighboring backlight partition in the horizontal and vertical directions;

[0150] Step S103: Calculate the grayscale compensation value of the current pixel based on the sum of squared distances.

[0151] The grayscale compensation method of this disclosure is applicable to the distance calculation circuit shown above. During pixel data transmission, the distance calculation circuit can be used to calculate the sum of squared distances between the current pixel and each neighboring backlight partition in real time. The sum of squared distances can be used to calculate the grayscale compensation value of the current pixel in subsequent calculations.

[0152] It is understandable that calculating the grayscale compensation value of the current pixel based on the distance between the current pixel and the neighboring backlight is a mature technology. This disclosure embodiment does not improve upon it. This disclosure embodiment only improves the specific method of obtaining the sum of squared distances between the current pixel and the neighboring backlight partition in the grayscale compensation method.

[0153] Obviously, the above embodiments of this disclosure are merely examples for clearly illustrating this disclosure, and are not intended to limit the implementation of this disclosure. For those skilled in the art, other variations or modifications can be made based on the above description. It is impossible to exhaustively list all implementation methods here. Any obvious variations or modifications derived from the technical solutions of this disclosure are still within the protection scope of this disclosure.

Claims

1. A distance operation circuit, characterized by comprising: The distance operation module is used for calculating the square of the distance of a current pixel point and a target backlight partition in a target direction, the target backlight partition is any neighborhood backlight partition of the current pixel point, the target direction is a horizontal direction or a vertical direction, and the distance operation module comprises a first operator, a shifter, a second operator, a third adder, a register and a first multiplexer. The first operator comprises two input ends, one of which inputs the coordinates of a target pixel point in the target direction in a current backlight partition, and the other of which inputs the distance between the current backlight partition and the target backlight partition in the target direction, the target pixel point is a previous pixel point adjacent to the current pixel point, and the current backlight partition is a backlight partition where the current pixel point is located. The input end of the shifter is connected with the output end of the first operator, the shifter is used for performing shift processing on the first distance value to obtain a second distance value, and the second distance value is twice the first distance value. The second operator comprises two input ends, one of which is connected with the output end of the shifter, and the other of which is connected with a first signal, the first signal is a first value, and the second operator is used for performing addition or subtraction operation on the data of the two input ends. The third adder comprises two input ends, one of which is connected with the output end of the first multiplexer, and the other of which is connected with the output end of the second operator, and the output end of the third adder is connected with the input end of the register. The first multiplexer comprises a first input end, a second input end, a control end and an output end, the first input end is connected with a second signal, the second input end is connected with the output end of the register, the control end is connected with a first control signal, the first multiplexer controls the output end to output the signal input by the first input end when the first control signal is a first level, and controls the output end to output the signal input by the second input end when the first control signal is a second level, the second signal is the square of the distance between the current backlight partition and the target backlight partition in the target direction, and the first control signal is the first level when the current pixel point crosses the backlight partition, and is the second level when the current pixel point does not cross the backlight partition.

2. The distance operation circuit according to claim 1, characterized by, The distance operation module further comprises: A first cross-zone identification unit, the input end of the first cross-zone identification unit is connected with pixel data, the output end is connected with the control end of the first multiplexer, and the first cross-zone identification unit is used for identifying whether the current pixel point crosses the backlight partition, and outputting the first control signal to the first multiplexer according to the identification result, and the pixel data represents the pixel data of the current pixel point.

3. The distance operation circuit according to claim 2, wherein The first cross-zone identification unit comprises a rising edge detection unit and an OR gate, the rising edge detection unit comprises a flip-flop and an AND gate, the flip-flop comprises a data input end, a clock signal input end and a main output end, the data input end is used for inputting pixel data, the clock signal input end is used for inputting a clock signal, the main output end is connected with one input end of the AND gate, the other input end of the AND gate is connected with a third signal, the output end of the AND gate is connected with one input end of the OR gate, the other input end of the OR gate is connected with the third signal, and the output end of the OR gate outputs the first control signal to the first multiplexer; when the third signal is a first level, it indicates that the current pixel point crosses the backlight partition; and when the third signal is a second level, it indicates that the current pixel point does not cross the backlight partition.

4. The distance operation circuit according to any one of claims 1 to 3, characterized by, The neighborhood backlight partitions of the current pixel point comprise a plurality of columns of backlight partitions distributed along a horizontal direction, the backlight partitions in the column where the current backlight partition is located are divided into two columns of sub-backlight partitions, the distance operation circuit comprises a horizontal direction distance operation circuit, the horizontal direction distance operation circuit comprises a plurality of distance operation modules, each distance operation module corresponds to one column of backlight partitions or one column of sub-backlight partitions, wherein the first operator and the second operator in the distance operation module corresponding to the column of backlight partitions on the first side of the current backlight partition are adders, the first operator and the second operator in the distance operation module corresponding to the column of backlight partitions on the second side of the current backlight partition are subtractors, the first operator in the distance operation module corresponding to the column of sub-backlight partitions on the first side of the vertical center line of the current backlight partition is a subtractor, and the second operator is a subtractor; the first operator in the distance operation module corresponding to the column of sub-backlight partitions on the second side of the vertical center line of the current backlight partition is a subtractor, and the second operator is an adder.

5. The distance operation circuit according to claim 4, wherein The neighborhood backlight partitions of the current pixel point comprise a plurality of rows of backlight partitions distributed along a vertical direction, the backlight partitions in the row where the current backlight partition is located are divided into two rows of sub-backlight partitions, the distance operation circuit comprises a vertical direction distance operation circuit, the vertical direction distance operation circuit comprises a plurality of distance operation modules, each distance operation module corresponds to one row of backlight partitions or one row of sub-backlight partitions, wherein the first operator and the second operator in the distance operation module corresponding to the row of backlight partitions on the first side of the current backlight partition are adders, the first operator and the second operator in the distance operation module corresponding to the row of backlight partitions on the second side of the current backlight partition are subtractors, the first operator in the distance operation module corresponding to the row of sub-backlight partitions on the first side of the horizontal center line of the current backlight partition is a subtractor, and the second operator is a subtractor; the first operator in the distance operation module corresponding to the row of sub-backlight partitions on the second side of the horizontal center line of the current backlight partition is a subtractor, and the second operator is an adder.

6. The distance operation circuit according to claim 4, wherein The neighborhood backlight partition of the current pixel point includes multiple rows of backlight partitions distributed along a vertical direction, the backlight partitions in the row where the current backlight partition is located are divided into two rows of sub-backlight partitions, the distance calculation circuit includes a vertical direction distance calculation circuit, the vertical direction distance calculation circuit includes the distance calculation module and a time-division multiplexing control module, the first calculator includes a first adder and a first subtractor, the second calculator includes a second adder and a second subtractor, the time-division multiplexing control module is configured to control the distance calculation module to calculate the distance squares of the current pixel point and each row of backlight partitions and each row of sub-backlight partitions in the vertical direction, wherein the time-division multiplexing control module is configured to enable the first adder and the second adder when the distance calculation module calculates the distance square of the current pixel point and the row of backlight partitions on the first side of the current backlight partition, the time-division multiplexing control module is configured to enable the first subtractor and the second subtractor when the distance calculation module calculates the distance square of the current pixel point and the row of backlight partitions on the second side of the current backlight partition, and the time-division multiplexing control module is configured to enable the first subtractor and the second subtractor when the current pixel point is located on the first side of the horizontal center line of the current backlight partition and enable the first subtractor and the second adder when the current pixel point is located on the second side of the horizontal center line of the current backlight partition.

7. The distance operation circuit according to claim 6, wherein The time-division multiplexing control module includes a second cross-zone identification unit, a shift control unit, a multiplexer unit and a shift register unit, wherein: The input end of the second cross-zone identification unit is connected with the pixel data, and the second cross-zone identification unit is configured to identify whether the current pixel point crosses the backlight partition, generate a second control signal according to the identification result and output the second control signal to the shift control unit; The shift control unit includes a plurality of cascaded flip-flops, the shift control unit includes a clock signal input end and a data input end, the clock signal input end is connected with a clock signal, the data input end is connected with the output end of the second cross-zone identification unit, and the output end of each flip-flop in the plurality of cascaded flip-flops forms a third control signal; The multiplexer unit includes a second multiplexer and a third multiplexer, the second multiplexer is configured to select one of multiple second signals and output the one of the multiple second signals to the second input end of the first multiplexer, the third multiplexer is configured to select one of multiple fourth signals and output the one of the multiple fourth signals to the other input end of the first calculator, the fourth signal represents the distance between the current backlight partition and the target backlight partition in the vertical direction, and the control ends of the second multiplexer and the third multiplexer are connected with the third control signal; and The shift register unit includes a plurality of cascaded registers, each register corresponds to a row of backlight partitions, and each register is configured to store the distance square of the current pixel point and the corresponding row of backlight partitions in the vertical direction.

8. The distance operation circuit according to claim 7, wherein The distance operation circuit further comprises a plurality of fourth adders, for any fourth adder, the fourth adder comprises a first input end and a second input end, the first input end is connected with an output end of a distance operation module in the horizontal direction distance operation circuit, and the second input end is connected with an output end of a register in the shift register unit.

9. The distance operation circuit according to claim 1, wherein The first value is a square of a second value, and the second value is a number of data channels when the display panel transmits data.

10. A gray scale compensation method, characterized by, The distance operation circuit suitable for any one of claims 1 to 9 comprises the following steps: Obtaining pixel data of a current pixel point; Inputting the pixel data into the distance operation circuit to obtain a distance square sum of the current pixel point and any adjacent backlight partition in a horizontal direction and a vertical direction; Calculating a gray scale compensation value of the current pixel point according to the distance square sum.

Images