Distance operation circuit and gray scale compensation method

Abstract

The invention provides a distance operation circuit and a gray scale compensation method, the distance operation circuit comprises a distance operation module, the distance operation module comprises a first arithmetic unit, a shifter, a second arithmetic unit, a third adder and a register; one input end of the first arithmetic unit inputs coordinates of a target pixel point in the current backlight partition in the target direction, the other input end of the first arithmetic unit inputs the distance between the current backlight partition and the target backlight partition in the target direction, the first arithmetic unit carries out addition or subtraction operation, and the shifter is connected with the output end of the first arithmetic unit. The shifting module is used for shifting the first distance value; one input end of the second arithmetic unit is connected with the output end of the shifter, the other input end of the second arithmetic unit is connected with the first signal, and the second arithmetic unit is used for carrying out addition or subtraction operation on data of the two input ends; one input end of the third adder is connected with the output end of the register, the other input end of the third adder is connected with the output end of the second arithmetic unit, and the output end of the third adder is connected with the input end of the register.

Description

Technical Field

[0001] The present disclosure relates to the field of display technology, and more specifically, to a distance calculation circuit and a grayscale compensation method. Background Art

[0002] In the field of display technology, local dimming (LD) is an effective means to improve the contrast and color expression of the picture. It adjusts the brightness of each backlight partition according to the actual needs of the display content. In LD technology, pixel grayscale compensation is a crucial link. In order to achieve high-precision compensation of the grayscale of a certain pixel, it is necessary to introduce the operation of the point spread function (PSF). The PSF operation needs to use the distance between the pixel and the adjacent backlight partition.

[0003] In the related art, a multiplier is used to calculate the distance between a pixel and an adjacent backlight area, which consumes a large amount of hardware resources. In addition, too many 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 the present disclosure is to provide a distance calculation circuit and a grayscale compensation method to solve at least one of the above technical problems.

[0005] In order to achieve the above objectives, the present invention adopts the following technical solutions:

[0006] In a first aspect, the present disclosure provides a distance operation circuit, including a distance operation module, the distance operation module is used to calculate the square of the distance between a current pixel and a target backlight partition in a 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 operation module includes a first operator, a shifter, a second operator, a third adder and a register;

[0007] The first operator includes two input terminals, one of which inputs the coordinates of the target pixel point in the current backlight partition in the target direction, and the other input inputs the distance between the current backlight partition and the target backlight partition in the target direction, the target pixel point is the previous pixel point adjacent to the current pixel point, and the current backlight partition is the backlight partition where the current pixel point is located, and the first operator 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 end of the shifter is connected to the output end of the first operator, and the shifter is used to perform shift processing on the first distance value to obtain a second distance value, where the second distance value is twice the first distance value;

[0009] The second operator comprises two input terminals, one of which is connected to the output terminal of the shifter, and the other is connected to a first signal, the first signal is a first value, and the second operator 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 is connected to the output terminal of the second operator. The output terminal of the third adder is connected to the input terminal of the register.

[0011] Optionally, the distance calculation module also includes a first multiplexer, the first multiplexer includes a first input terminal, a second input terminal, a control terminal and an output terminal, the first input terminal is connected to the second signal, the second input terminal is connected to the output terminal of the register, the control terminal is connected to the first control signal, 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 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 the backlight partition, and is at a second level when the current pixel does not cross the backlight partition.

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

[0013] A first cross-zone identification unit, wherein the input end of the first cross-zone identification unit is connected to the pixel data, and the output end is connected to the control end of the first multiplexer, and is used to identify whether the current pixel point crosses the backlight partition, and output 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.

[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 trigger and an AND gate, the trigger 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, the clock signal input terminal is used to input a clock signal, the main output terminal is connected to one of the input terminals of the AND gate, 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 of the input terminals of the OR gate, the other input terminal of the OR gate is connected to the third signal, and 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 point crosses the backlight partition, and when the third signal is at a second level, it indicates that the current pixel point does not cross the backlight partition.

[0015] Optionally, the neighborhood backlight partition of the current pixel point includes multiple columns of backlight partitions distributed in the horizontal direction, the backlight partition of the column where the current backlight partition is located is divided into two columns of sub-backlight partitions, the distance operation circuit includes a horizontal distance operation circuit, the horizontal distance operation circuit includes a plurality of distance operation modules, each distance operation module corresponds to a column of backlight partition or a column of sub-backlight partitions, wherein, in the distance operation module corresponding to the column backlight partition on the first side of the current backlight partition, the first operator and the second operator are adders, and in the distance operation module corresponding to the column backlight partition on the second side of the current backlight partition, the first operator and the second operator are subtractors, in the distance operation module corresponding to the column sub-backlight partition 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, and in the distance operation module corresponding to the column sub-backlight partition 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 point includes multiple rows of backlight partitions distributed in 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 operation circuit includes a vertical distance operation circuit, the vertical distance operation circuit includes a plurality of distance operation modules, each distance operation module corresponds to a row of backlight partitions or a row of sub-backlight partitions, wherein, in the distance operation module corresponding to the row backlight partition on the first side of the current backlight partition, the first operator and the second operator are adders, and in the distance operation module corresponding to the row backlight partition on the second side of the current backlight partition, the first operator and the second operator are subtractors, in the distance operation module corresponding to the row sub-backlight partition 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, and in the distance operation module corresponding to the row sub-backlight partition 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 point includes multiple rows of backlight partitions distributed in 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, the vertical distance calculation circuit includes the distance calculation module and a time-sharing multiplexing control module, the first operator includes a first adder and a first subtractor, the second operator includes a second adder and a second subtractor, the time-sharing multiplexing control module is used to control the distance calculation module to time-share the distance square between the current pixel point and each row of backlight partitions and each row of sub-backlight partitions in the vertical direction, wherein the time-sharing multiplexing control module controls the distance calculation module to calculate the current pixel point. When the square of the distance between the previous 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 operation module to calculate the square of the 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 operation module to calculate the square of the 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] A second cross-region identification unit, wherein an input end of the second cross-region identification unit is connected to the pixel data, and is used to identify whether the current pixel point crosses the backlight partition, and generate a second control signal according to the identification result and output it to the shift control unit;

[0020] A shift control unit, the shift control unit comprising a plurality of cascaded flip-flops, the shift control unit comprising a clock signal input terminal and a data input terminal, the clock signal input terminal being connected to a clock signal, the data input terminal being connected to an output terminal of the second cross-region identification unit, and an output terminal of each flip-flop in the plurality of cascaded flip-flops forming a third control signal;

[0021] a multiplexer unit, the multiplexer unit comprising a second multiplexer and a third multiplexer, the second multiplexer being used to select one path from the multiple second signals to be output to the second input terminal of the first multiplexer, the second multiplexer being used to select one path from the multiple fourth signals to be output to the other input terminal of the first operator, the fourth signal indicating the distance between the current backlight partition and the target backlight partition in the vertical direction, the control terminals of the second multiplexer and the third multiplexer being connected to the third control signal; and

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

[0023] Optionally, the distance operation circuit also includes multiple fourth adders, and for any fourth adder, the fourth adder includes a first input end and a second input end, the first input end is connected to the output end of a distance operation module in the horizontal distance operation circuit, and the second input end is connected to the output end of a register in the shift register unit.

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

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

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

[0027] Inputting the pixel data into the distance calculation circuit to obtain the sum of the squares of the distances between the current pixel and any neighboring backlight partition in the horizontal direction and the vertical direction;

[0028] The grayscale compensation value of the current pixel is calculated according to the sum of the squares of the distances.

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

[0030] The distance calculation circuit of the disclosed embodiment can calculate the square of the distance between the current pixel and any adjacent backlight partition in the horizontal or vertical direction through a first operator, a shifter, a second operator, a third adder and a register. It uses addition / subtraction of small operands, shift operations and simple logical control to implement the distance square operation, avoiding the use of multipliers, thereby reducing resource consumption, improving computing efficiency and helping to increase the maximum operating frequency of the LD module. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The specific implementation methods of the present disclosure are further described in 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 the present disclosure;

[0033] Figure 2 Schematic diagram of the relationship between the horizontal distances between two adjacent pixels in the same row and any adjacent backlight subarea Wmn;

[0034] Figure 3is a schematic diagram of the relationship between the vertical distances between two adjacent pixels in the same column and any adjacent backlight subarea Wmn;

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

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

[0037] Figure 6 is a circuit diagram of a distance operation module in a horizontal distance operation circuit;

[0038] Figure 7 is a circuit diagram of a distance operation module in a vertical distance operation circuit;

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

[0040] Fig. 9 A schematic diagram of the output results of a distance operation module in a horizontal distance operation circuit in a 4-lane mode provided in an embodiment of the present disclosure. DETAILED DESCRIPTION

[0041] In order to make the purpose, technical solution and advantages of the embodiments of the present disclosure clearer, the technical solution of the embodiments of the present disclosure will be clearly and completely described below in conjunction with the drawings of the embodiments of the present disclosure. Obviously, the described embodiments are part of the embodiments of the present disclosure, not all of the embodiments. Based on the described embodiments of the present disclosure, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present disclosure.

[0042] Unless otherwise defined, the technical terms or scientific terms used in the present disclosure should be understood by people with ordinary skills in the field to which the present disclosure belongs. The "first", "second" and similar words used in the present disclosure do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, similar words such as "one", "one" or "the" do not indicate quantity restrictions, but indicate that there is at least one. Similar words such as "include" or "comprise" mean that the elements or objects appearing before the word cover the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Similar words such as "connect" or "connected" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0043] In the local dimming (LD) function, the grayscale compensation of pixels is a crucial link, which is directly related to the display effect of the final picture. The core of grayscale compensation is to accurately adjust the grayscale value of pixels according to the relative distance between pixels and adjacent backlight partitions, that is, the influence of point spread function (PSF). The relative distance here usually refers to the square root of the sum of the squares of the distances between pixels and backlight partitions in the horizontal (H) and vertical (V) directions, which is used to quantify the spatial relationship between pixels and backlight partitions.

[0044] Among them, the adjacent backlight partition of a certain pixel point can adopt 3*3 neighborhood backlight, 5*5 neighborhood backlight, 7*7 neighborhood backlight, 9*9 neighborhood backlight, 11*11 neighborhood backlight and other methods, please refer to Figure 1 , Figure 1 It is a schematic diagram of 5*5 neighborhood backlight partition, such as Figure 1 As shown, the neighborhood backlight partition of a certain pixel point P includes 24 adjacent backlight partitions centered on the backlight partition W22 where the pixel point P is located, which are respectively recorded 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 the pixel point P, it is necessary to calculate the relative distance between the pixel point P and the 24 adjacent backlight partitions. Figure 1 Taking the backlight partition W00 as an example, the square of the relative distance s between the pixel point P and the backlight partition W00 is expressed as s 2 =h 2 +v2 , where h is the horizontal distance between the pixel point P and the backlight partition W00, v is the vertical distance between the pixel point P and the backlight partition W00, and (x, y) represents the coordinates of the pixel point P in the backlight partition W22.

[0045] In the traditional method, multipliers and adders are mainly used to calculate the square of the above distance. Specifically, the multiplier is first used to calculate the square of the distance between the pixel point P and the neighborhood backlight partition in the horizontal direction H and the vertical direction V, and then the two square values ​​are added by the adder, and finally the final relative distance is obtained by the square root operation. However, considering the extensiveness of the backlight neighborhood, for example, for a 5*5 neighborhood backlight, for each pixel point P, it is necessary to calculate the relative distance between the pixel point P and the surrounding 24 backlight partitions, which requires 48 multipliers to achieve, and the multiplier has the disadvantages of large circuit resources and low circuit operation frequency. Too many multiplication operations will reduce the maximum operating frequency of the LD function, which is not conducive to hardware implementation.

[0046] In order to solve the above technical problems, the embodiment of the present disclosure proposes a new type of distance operation circuit, the core of which is to use addition / subtraction of small operands, shift operations and simple logical control to realize distance square operations, avoid the use of multipliers, thereby reducing resource consumption and improving computing efficiency.

[0047] The basic principle adopted by the distance calculation circuit of the embodiment of the present disclosure can be referred to Figure 2 and Figure 3 .

[0048] Figure 2 Schematic diagram of the horizontal distance between two pixels with the same vertical coordinate V and adjacent to each other in the horizontal direction and any adjacent backlight partition Wmn, where m indicates that the backlight partition Wmn is the mth in the vertical direction V, and n indicates that the backlight partition Wmn is the nth in the horizontal direction H. Figure 2 As shown, in the display panel, for two adjacent pixel points P in a row i With P i+1 , the i-th pixel P i The relative distance from the backlight partition Wmn is represented by S_Q mn , the i-th pixel P i The relative distance from the backlight partition Wmn in the horizontal direction H is represented by d_h n , the relative distance in the vertical direction V is expressed as d_v m , the i+1th pixel P i+1 The relative distance from the backlight partition Wmn is represented as S_Q' mn , the i+1th pixel P i+1 The relative distance from the backlight partition Wmn in the horizontal direction H is expressed as d_h'n , then it satisfies:

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

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

[0051] If the pixel point P i+1 With the previous pixel P i The distance in the horizontal direction H is 1, that is, d_h' n =d_h n +1, then:

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

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

[0054] That is, for two adjacent pixels P in a row i With P i+1 , pixel P i+1 The square of the distance from the backlight partition Wmn in the horizontal direction H can be obtained by the adjacent previous pixel point P i The square of the distance from the backlight partition Wmn in the horizontal direction H plus the compensation component is obtained, where the compensation component is:

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

[0056] For the first pixel point P0 in a row of the current backlight partition W22, the position relationship between the pixel point P0 and the backlight partition Wmn satisfies:

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

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

[0059] Among them, DIS_H n represents the horizontal distance between the backlight partition W22 and the backlight partition Wmn, that is, the square of the distance between the first pixel P0 in a row corresponding to the current backlight partition W22 and Wmn, which can be based on (DIS_H n ) 2 Add the compensation component to get, where the compensation component is 2*(DSI_H n )+1.

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

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

[0062] (1) The backlight subarea Wmn is located in the first area, then the pixel point P i+1 The horizontal distance from the backlight partition Wmn gradually increases with the transmission of pixel data, that is, the pixel point P i+1 The horizontal distance between the backlight partition Wmn and the pixel point P i The horizontal distance between the backlight partition Wmn satisfies the above formulas (1.3) and (1.4);

[0063] (2) The backlight subarea Wmn is located in the second area, then the pixel point P i+1The horizontal distance from the backlight partition Wmn gradually decreases with the transmission of pixel data, that is, the pixel point P i+1 The horizontal distance between the backlight partition Wmn and the pixel point P is smaller than i The horizontal distance between the backlight partition Wmn satisfies the 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(Formula 1.9)

[0066] Similarly, please refer to Figure 3 , Figure 3 Schematic diagram of the vertical distance between two adjacent pixels in the vertical direction and any backlight partition Wmn with the same horizontal coordinate H, wherein m indicates that the backlight partition Wmn is the mth in the vertical direction V, and n indicates that the backlight partition Wmn is the nth in the horizontal direction H. Figure 3 As shown, in the display panel, for two adjacent pixel points P in a column j With P j+1 , assuming that the j-th pixel P j The distance from the backlight partition Wmn in the vertical direction V is represented as d_v m , the j+1th pixel point P j+1 The distance from the backlight partition Wmn in the vertical direction V is represented as d_v' m , then the following relations can be derived in sequence:

[0067] For the backlight partitions above the horizontal center line L2, such as W1n, W2n, where n=0, 1, 2, 3 or 4, it satisfies:

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

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

[0070] That is, for two adjacent pixels P in a column j With P j+1 , pixel P j+1 The square of the distance from the backlight partition Wmn in the vertical direction V can be obtained by the adjacent previous pixel point P j The square of the distance from the backlight partition Wmn in the vertical direction V plus the compensation component is obtained, where the compensation component is:

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

[0072] Among them, for the first pixel point P0 in a certain column in the current backlight partition W22, the position relationship between the pixel point P0 and the backlight partition Wmn satisfies:

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

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

[0075] Among them, DIS_V m The vertical distance between the backlight partition W22 and the backlight partition Wmn, that is, the square of the 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 Add the compensation component to get, where the compensation component is 2*(DSI_V m Similarly, for the first pixel point P0 in a column, assuming that the first pixel point P0 is set to be located on the boundary line of the backlight subarea W22, it can also be understood that the distance between the first pixel point P0 and Wmn is DIS_V m , the second pixel and subsequent pixels can be calculated using the square of the distance to the first pixel plus the compensation component.

[0076] Similarly, for the backlight partitions below the horizontal center line L2, such as W3n and W4n, the following conditions are satisfied:

[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(Formula 2.7)

[0079] In summary, the square of the distance between the current pixel and any adjacent backlight partition Wmn, whether in the horizontal direction H or the vertical direction V, has a logical iterative relationship as shown in (Formula 1.3), (Formula 1.4), (Formula 1.8) and (Formula 1.9) between its adjacent pixels. In the process of pixel data transmission, the square sum operation can be obtained by using the iterative relationship to realize the operation of the two components of the horizontal direction H and the vertical direction V and then adding them. This iterative relationship only involves two operations, addition or subtraction and shift. Combined with relatively simple control logic, complex square sum operations can be realized, which can avoid 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 a distance calculation circuit provided by an embodiment of the present disclosure, Figure 5 This is a schematic diagram of the overall architecture of another embodiment of the distance calculation circuit provided by the embodiment of the present disclosure, Figure 4 and Figure 5 The distance operation circuit is used to calculate the sum of the squares of the distances between the current pixel and the target backlight partition Wmn, wherein 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 expressed by the square root of the sum of the squares of the horizontal distance and the vertical distance, so the distance operation circuit needs to include a horizontal distance operation circuit 110 and a vertical distance operation circuit 120, wherein the horizontal distance operation 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 operation circuit 120 is used to calculate the square of the vertical distance between the current pixel and the target backlight partition Wmn.

[0081] Among them, in the horizontal direction and the vertical direction, the principle of implementing the distance square operation using addition / subtraction of small operands, shift operations and simple logical control is the same. In the embodiment of the present disclosure, the circuit unit that implements the distance square operation is represented as a distance operation module 20. The distance operation module 20 is used to calculate the square of the distance between the current pixel point and the target backlight partition Wmn in the target direction, which is the horizontal direction or the vertical direction, wherein the target backlight partition Wmn is any neighboring backlight partition of the current pixel point.

[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 distance between the current pixel point and the target backlight partition Wmn in the horizontal direction. 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 distance between the current pixel point and the target backlight partition Wmn in the vertical direction.

[0083] Combine the following Figures 6 to 8 Introduce the circuit schematic diagram of the distance operation module, where: Figure 6 It is a schematic diagram of the circuit structure of the distance calculation module in the horizontal direction. Figure 7 It is a schematic diagram of the circuit structure of the distance calculation module in the vertical direction. Figure 8 It 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 operation module 20 includes a first operator U1, a shifter S, a second operator U2, a third adder Add2 and a register R.

[0085] Among them, the first operator U1 includes two input ends, one of which inputs the coordinates of the target pixel point in the current backlight partition in the target direction, and the other input inputs the distance between the current backlight partition and the target backlight partition Wmn in the target direction, the target pixel point is the previous pixel point adjacent to the current pixel point, and the current backlight partition is the backlight partition where the current pixel point is located. The first operator U1 is used to perform addition or subtraction operations on the signals input from the two input ends to obtain a first distance value, and the first distance value is also the distance between the target pixel point and the target backlight partition in the target direction.

[0086] An input end of the shifter S is connected to an output end of the first operator U1 , and the shifter S is used to perform shift processing on the first distance value to obtain a second distance value, where the second distance value is twice the first distance value.

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

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

[0089] Compared with the related art, the distance calculation circuit of the embodiment of the present invention can calculate the square of the distance between the current pixel and any adjacent backlight partition in the horizontal or vertical direction through a first operator, a shifter, a second operator, a third adder and a register. It uses addition / subtraction of small operands, shift operations and simple logical control to achieve the distance square operation, avoiding the use of multipliers, thereby reducing resource consumption, improving computing efficiency and helping to increase the maximum operating frequency.

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

[0091] Among them, 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 the second signal, the second input terminal is connected to the output terminal of the register R, the control terminal is connected to the first control signal, 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 the backlight partition, and is at a second level when the current pixel does not cross the backlight partition.

[0092] Specifically, Figure 6 As shown, when the distance calculation module 20 is used to calculate the distance between the current pixel and the target backlight partition Wmn in the horizontal direction (that is, the vertical distance in the horizontal direction), it is assumed that the current pixel is represented by P i+1 , the target pixel is represented by P i , the input signal of the first operator U1, cnt_h i Represents the target pixel P i Horizontal coordinate x in the current backlight partition, distance_hi Indicates the distance between the current backlight partition and the target backlight partition Wmn in the horizontal direction H, cnt_h 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. The distance between the current backlight partition W22 and the target backlight partition Wmn in the horizontal direction H can be specifically 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 5*5 neighborhood backlight partition, the current backlight partition is W22, then:

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

[0095] For the second column of target backlight partitions Wm1, the distance between the current backlight partition W22 and the target backlight partition Wmn in the horizontal direction H is 0.5*L, that is, distance_h i =0.5*L, when calculating the horizontal distance between the current backlight subarea and the second column target backlight subarea Wm1, the first operator U1 is an adder, and its output is x+0.5*L;

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

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

[0098] For the third column of target backlight partition Wm2, when the target pixel point P i When the target pixel point P is located on the left side 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, and the first operator U1 is a subtractor, and its output is 0.5*Lx; i When located on the right side 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, and the first operator U1 is a subtractor, and its output is x-0.5*L.

[0099] After the addition or operation of the first operator U1, the first distance value obtained is expressed as d_h i , that is, the target pixel P i The horizontal distance from the target backlight partition Wmn. For example, Figure 3 As shown, for the first column of target backlight partitions, the target pixel point P i The horizontal distance d_h i =1.5*L+x.

[0100] In the embodiment of the present disclosure, the first distance value is a binary number. The shifter S is used to shift the first distance value to the left by one position, which means that the first distance value is multiplied by 2, that is, the output of the shifter S is 2*(d_h i ).

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

[0102] The first value const_data_h is a fixed value, and the first value const_data_h is 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, and the second value b is the number of data channels when the display panel transmits data. For example, for a display panel in 1lane mode, one pixel is transmitted each time, that is, the current pixel P at this time i+1 The distance between the adjacent previous pixel (that is, the pixel transmitted at the last moment) is 1 pixel. At this time, const_data_h = 1. For a display panel in 2lane mode, 2 pixels are transmitted each time. That is, the current pixel P i+1The distance between the adjacent previous pixel is 2 pixels. At this time, const_data_h=4. For a display panel in 4-lane mode, 4 pixels are transmitted each time, that is, the current pixel P i+1 The distance between the adjacent previous pixel point is 4 pixel points, const_data_h=16, and so on.

[0103] In the embodiment of the present disclosure, the 1 lane mode is taken as an example, the first value is a fixed value 1, and when the second operator U2 performs an addition operation, the output of the second operator U2 is 1+2*(d_h i ), when the second operator U2 performs a subtraction operation, the output of the second operator U2 is 1-2*(d_h i ).

[0104] One of the two input signals of the third adder Add2 is 1+2*(d_h i ) or 1-2*(d_h i ), and the other is the output of the first multiplexer Mux, wherein the output of the first multiplexer Mux is the target pixel point P i The square of the distance from the target backlight partition Wmn in the horizontal direction H, that is, (d_h i ) 2 , so 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 point P i+1 The square of the distance from the target backlight partition Wmn in the horizontal direction H.

[0105] Specifically, Figure 6 As shown, the first multiplexer Mux-h is used to output the data of the first input terminal or the data of the second input terminal under the control of the first control signal, wherein the data of the first input terminal is the second signal SQUAR_DIS_Hi, and the second signal SQUAR_DIS_Hi represents the square of the distance between the current backlight partition and the target backlight partition Wmn in the horizontal direction, that is, distance_h i The data at the second input terminal is the output of register R.

[0106] For the distance calculation module 20, if the current pixel is the first pixel P0 of a row in 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 of a row, for example, the second pixel P1, the output of the register R may be (d_h0) 2 +2*(d_h0)+1, which is (d_h1) 2 , which represents the square of the distance between the second pixel point P1 and the target backlight partition Wmn in the horizontal direction H. At this time, the first control signal controls the signal of the first multiplexer Mux-h output register R, and so on, the square of the distance between each subsequent pixel point and the target backlight partition Wmn in the horizontal direction H can be obtained.

[0107] Among them, the current pixel point P i+1 Cross-backlight partition means that in the horizontal direction H, the current pixel point P i+1 It is from one backlight partition to a new backlight partition. The current pixel point P i+1 Not crossing the backlight partition means that in the horizontal direction H, the current pixel point P i+1 The target pixel is located in the same backlight partition. For example, in the horizontal direction, each backlight partition includes 100 pixels. Assume that the pixels in the backlight partition W22 are respectively denoted as P 0， P 1， P 2， P 3， ......P 99， The pixels in the backlight partition W23 include P 100， P 101， P 102， P 103 ........P 199 , then if the current pixel point P i+1 P 100 , indicating that the current pixel point P i+1 Across backlight partitions, if the current pixel point P i+1 P 99 , indicating that the current pixel point P i+1 The pixel point that crosses the backlight partition can also be understood as the boundary pixel point within the backlight partition, or the first pixel point of the backlight partition in the horizontal direction H, so the first control signal needs to be the first level at this time, otherwise the first control signal is the second level.

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

[0109] Similarly, if Figure 7 As shown, when the distance calculation module 20 is used to calculate 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 by P j+1 , the target pixel is represented by P j , the input signal of the first operator U1, cnt_v j Represents the target pixel P j The vertical coordinate y in the current backlight partition, distance_v j Indicates the distance between the current backlight partition and the target backlight partition Wmn in the vertical direction V. The first value const_data_v input by the second operator U2 has the same meaning as the first value const_data_h. The second signal SQUAR_DIS_Vj indicates the square of the distance between the current backlight partition and the target backlight partition Wmn in the vertical direction V. That is, the second signal SQUAR_DIS_Vj is a fixed value, which is distance_v j The first control signal input to the control end 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 in the current backlight partition. At this time, it crosses the backlight partition. At this time, 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. At this time, the output of the first multiplexer Mux-v is (d_vj ) 2 +2*(d_v j )+1 or (d_v j ) 2 -2*(d_v j )+1.

[0110] In a possible implementation, the distance calculation module 20 also 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, for identifying whether the current pixel point crosses the backlight partition, and outputting the first control signal to the first multiplexer Mux according to the identification result, and the pixel data represents the pixel data of the current pixel point.

[0111] Optional, such as Figure 6 As shown, the first cross-region identification unit 210 includes a rising edge detection unit and an OR gate OR, the rising edge detection unit includes a trigger DFF and an AND gate AND, the trigger 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 pixel data de_i 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 AND is connected to the third signal lane_end_flag, the output terminal of the AND gate AND is connected to one of the input terminals of the OR gate OR, the other input terminal of the OR gate OR is connected to the third signal lane_end_flag, and the output terminal of the OR gate OR outputs the first control signal to the first multiplexer Mux-h, wherein when the third signal lane_end_flag is at a first level, it indicates that the current pixel point crosses a row, and when the third signal lane_end_flag is at a second level, it indicates that the current pixel point does not cross a row.

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

[0113] Specifically, the trigger DFF is a D-type trigger. When the clock signal clk changes from a low level to a high level, if the data input terminal D is at a high level, the main output terminal Q will follow D to change to a high level, and if D is at a low level, the main output terminal Q will follow D to change to a low level. When the clock signal clk changes to a low level again, the main output terminal Q will maintain the previous value, that is, the value of the main output terminal Q will change at the rising edge of each positive pulse cycle and remain unchanged before the next rising edge.

[0114] Wherein, the pixel data de_i is at a high level to indicate that the current pixel is valid, and the pixel data de_i is at a low level to indicate that the current pixel is invalid. When the pixel data de_i changes from a low level to a high level, the output of the AND gate AND is at a high level, indicating that a new backlight partition is entered at this time. The third signal lane_end_flag is used to indicate whether it is the last pixel of the current row. The third signal lane_end_flag is at a first level (high level) to indicate that a new row is entered at this time, that is, the current pixel and its previous pixel are in different rows, and the current pixel crosses rows, which is the first pixel of a row in the current backlight partition. The third signal lane_end_flag is at a second level (low level) to indicate that the current pixel does not cross rows, that is, the current pixel and its previous pixel are in the same row.

[0115] In the embodiment of the present disclosure, for the distance operation module 20 in the horizontal distance operation circuit 110, when the current pixel enters a new backlight partition or a new row, the first control signal is at the first level, and the distance operation module 20 outputs the second signal SQUAR_DIS_Hi to the output port squar_i of the distance operation module 20, which is used for the square iterative operation of the next adjacent pixel, and in each clock cycle thereafter, the first multiplexer Mux-h selects the square of the distance H in the horizontal direction obtained through the iterative operation, 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 operation module 20 in the vertical distance operation circuit 120, when the current pixel enters a new backlight partition, the first control signal is at the first level, and the distance operation module 20 outputs the second signal SQUAR_DIS_Vj to the output port squar_j of the distance operation module 20, which is used for the square iterative operation of the next adjacent pixel, and in each clock cycle thereafter, the first multiplexer Mux-v selects the square of the vertical distance obtained through the iterative operation, that is, the data of the register R (d_v 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 point includes multiple columns of backlight partitions distributed in the horizontal direction and multiple rows of backlight partitions distributed in the vertical direction, and the backlight partition of the column where the current backlight partition is located is divided into two columns of sub-backlight partitions, and the backlight partition of the row where the current backlight partition is located is divided into two rows of sub-backlight partitions, wherein the backlight partition of 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 dividing line, and the backlight partition of 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 dividing line.

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

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

[0120] Among them, in each neighborhood backlight partition, for the backlight partitions in the same column, the horizontal distance between each backlight partition in the column and the current pixel is the same, so each column of backlight partitions can share a distance calculation module 20. Exemplarily, for a 5*5 neighborhood backlight partition, the horizontal distance calculation circuit 110 includes 6 distance calculation modules 20. Assume that from left to right, the distance calculation modules 20 corresponding to the 6 columns of backlight partitions or sub-backlight partitions are respectively recorded as SQUAR-H0, SQUAR-H1, SQUAR-H21, SQUAR-H22, SQUAR-H3, and SQUAR-H4, where SQUAR-H21 and SQUAR-H22 are used to calculate the horizontal distance between the current pixel and the backlight partition of the column where the current backlight partition is located. In each distance calculation module, the second signal SQUAR_DIS_Hi and the signal distance_hi It may be different, which is determined by the horizontal distance between each column of backlight partitions and the current backlight partition W22.

[0121] according to Figure 3 and Figure 4 It can be seen that, assuming that the current pixel is represented by P i+1 , the current backlight partition where it is located is W22, then for each neighboring backlight partition on the left side of the current backlight partition W22, the current pixel point P i+1 Compared with the horizontal distance of any neighboring backlight partition, the previous pixel P i The horizontal distance from the backlight partition is increasing, and for each neighboring backlight partition on the right side of the current backlight partition W22, the current pixel point P i+1 Compared with the horizontal distance of any neighboring backlight partition, the previous pixel P i The horizontal distance from the backlight partition is decreasing, so for the two columns of backlight partitions on the left, the first operator U1 and the second operator U2 in the distance calculation module 20 are adders, that is, the first operator U1 and the second operator U2 in SQUAR-H0 and SQUAR-H1 are adders, and for the two columns of backlight partitions on the right, the first operator U1 and the second operator U2 in the distance calculation module 20 are subtractors, that is, the first operator U1 and the second operator U2 in SQUAR-H3 and SQUAR-H4 are subtractors. For the neighboring backlight partitions (such as W02, W12, W32, and W42) in the column where the current backlight partition W22 is located, at the current pixel point P i+1 When it is on the left side of the vertical center line, the current pixel point P i+1 Compared with the horizontal distance of the backlight partition of the current column neighborhood, the previous pixel point P i The horizontal distance from the backlight partition is decreasing, so the first operator U1 is a subtractor, and the second operator U2 is a subtractor, that is, the first operator U1 in SQUAR-H21 is a subtractor, and the second operator U2 is a subtractor; and the current pixel point P i+1 When it is on the right side of the vertical center line, the current pixel point P i+1 Compared with the horizontal distance of the backlight partition of the current column neighborhood, the previous pixel point P i The horizontal distance from the backlight partition is increasing, therefore, the first operator U1 is a subtractor, and the second operator U2 is an adder, that is, the first operator U1 in SQUAR-H22 is a subtractor, and the second operator U2 is an adder.

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

[0123] Among them, for the backlight partitions in the same row, the vertical distances between each backlight partition in the row and the current pixel are the same, so each row of backlight partitions can share one distance calculation module 20. Exemplarily, for a 5*5 neighborhood backlight partition, the vertical distance calculation circuit 120 includes 6 distance calculation modules 20. Assuming that from top to bottom, each distance calculation module is recorded as SQUAR-V0, SQUAR-V1, SQUAR-V21, SQUAR-V22, SQUAR-V3, and SQUAR-V4, then in each distance calculation module, the second signal SQUAR_DIS_Vj and the signal distance_v j It may be different, which is determined by the vertical distance between each column of backlight partitions and the current backlight partition W22.

[0124] according to Figure 3 and Figure 4 It can be seen that, assuming that the current pixel is represented by P j+1 , the current backlight partition where it is located is W22, then for each neighboring backlight partition on the upper side of the current backlight partition W22, the current pixel point P j+1 Compared with the vertical distance of any backlight partition, the previous pixel point P j The vertical distance from the backlight partition is increasing, and for each neighboring backlight partition below the current backlight partition W22, the current pixel point P j+1 Compared with the horizontal distance of any backlight partition, the previous pixel point P jThe vertical distance from the backlight partition is decreasing, so for the two rows of backlight partitions on the upper side of the current backlight partition W22, the first operator U1 and the second operator U2 in the distance calculation module 20 are adders, and for the two rows of backlight partitions on the lower side of the current backlight partition W22, the first operator U1 and the second operator U2 in the distance calculation module 20 are subtractors. For the neighboring backlight partitions (such as W20, W21, W23, and W24) of the row where the current backlight partition W22 is located, at the current pixel point P j+1 When the current pixel point P is located above the horizontal center line L2, j+1 Compared with the vertical distance of the backlight partition of the current column neighborhood, the previous pixel point P j The vertical distance from the backlight partition is decreasing, so the first operator U1 is a subtractor, and the second operator U2 is a subtractor, that is, the first operator U1 in SQUAR-V21 is a subtractor, and the second operator U2 is a subtractor; and the current pixel point P j+1 When the current pixel point P is located below the horizontal center line L2, j+1 Compared with the vertical distance of the backlight partition of the current column neighborhood, the previous pixel point P j The vertical distance from the backlight partition is increasing, therefore, the first operator U1 is a subtractor, and the second operator U2 is an adder, that is, the first operator U1 in SQUAR-V22 is a subtractor, and the second operator U2 is an adder.

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

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

[0127] In the embodiment of the present disclosure, in the vertical distance operation circuit 120, only one distance operation module 20 is set, and the time-sharing multiplexing control module 30 is used to control the distance operation module 20 to sequentially calculate the square of the vertical distance between the current pixel point and each row of backlight partitions. Such a setting can reduce the consumption of hardware resources. Tasks that originally require multiple distance operation modules can be completed by a time-sharing multiplexing circuit. The resource utilization rate is high and the hardware investment cost is reduced, but the time-sharing calculation method will increase the time consumption. In the specific implementation, the appropriate vertical distance operation circuit can be selected according to actual needs, such as resource consumption, operating efficiency, etc., and the embodiment of the present disclosure does not limit it.

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

[0129] The input end of the second cross-area identification unit 310 is connected to the pixel data de_j, and is used to identify whether the current pixel point crosses the backlight partition, and generate a second control signal according to the identification result and output it to the shift control unit 320.

[0130] For example, Figure 8 As shown, the second cross-region identification unit 310 includes a trigger DFF and an AND gate AND, the trigger 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 AND is connected to the pixel data de_j, and the output terminal of the AND gate AND is connected to the input terminal of the shift control unit 320.

[0131] The shift control unit 320 includes a plurality of cascaded triggers DFF, and 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-region identification unit 310, and the output terminal of each trigger in the plurality of cascaded triggers DFF forms a third control signal.

[0132] The number of triggers DFF in the shift control unit 320 is the same as the number of rows of the neighboring backlight partitions in the vertical direction V, and the shift control unit 320 is used to perform shift processing on the second control signal. Figure 8 As shown, for a 5*5 neighborhood backlight partition, the shift control unit 320 needs to include 5 triggers DFF, and the 5-bit third control signal is formed by the 5 triggers DFF. Each trigger DFF includes a clock signal input terminal, a data input terminal D, and a main output terminal Q, wherein the data input terminal of the first trigger DFF is connected to the output terminal of the AND gate AND in the second cross-region identification unit 310, and the data input terminals of other triggers DFF are connected to the main output terminal Q of the previous trigger DFF, and the clock signal input terminals of each trigger DFF are connected to the clock signal clk, and the third control signal can be generated by cascading multiple triggers DFF.

[0133] The multiplexer unit 330 includes a second multiplexer Mux-va and a third multiplexer Mux-vb, wherein the second multiplexer Mux-va is used to select one path from the multiple second signals SQUAR_DIS_Vj to be output to the second input end of the first multiplexer Mux-v, and the second multiplexer Mux-vb is used to select one path from the multiple fourth signals distance_vj to be output to the other input end of the first operator U1, wherein the fourth signal distance_vj represents the distance between the current backlight partition and the target backlight partition in the vertical direction V, and the control ends of the second multiplexer Mux-va and the third multiplexer Mux-vb are connected to the output end of the shift control unit 320, i.e., the third control signal.

[0134] like Figure 8 As shown, for a 5*5 neighborhood backlight partition, the multi-channel second signal SQUAR_DIS_Vj includes 5 channels, which are assumed to be recorded 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 square of the distance between the current backlight partition and the first row target backlight partition W0n in the vertical direction V, and SQUAR_DIS_V1 represents the current backlight partition. SQUAR_DIS_V2 represents the square of the distance in the vertical direction V between the current backlight partition and the target backlight partition in the third row, that is, the backlight partition W2n in the row where the current backlight partition is located; SQUAR_DIS_V3 represents the square of the distance in the vertical direction V between the current backlight partition and the target backlight partition W3n in the fourth row; SQUAR_DIS_V4 represents the square of the distance in the vertical direction V between the current backlight partition and the target backlight partition W4n in the fifth row.

[0135] Correspondingly, the multi-channel fourth signal distance_v j It includes 5 paths, which are assumed to be recorded as the fourth signal distance_v0, distance_v1, distance_v2, distance_v3, and distance_v4 respectively, wherein distance_v0 represents the distance between the current backlight partition and the first row target backlight partition W0n in the vertical direction V, distance_v1 represents the distance between the current backlight partition and the second row target backlight partition W1n in the vertical direction V, distance_v2 represents the distance between the current backlight partition and the third row target backlight partition W2n in the vertical direction V, distance_v3 represents the distance between the current backlight partition and the fourth row target backlight partition W3n in the vertical direction V, and distance_v4 represents the distance between the current backlight partition and the fifth row target backlight partition W4n in the vertical direction V.

[0136] The connection between the control ends of the second multiplexer Mux-va and the third multiplexer Mux-vb and the output ends of the shift control unit 320 can be understood as follows: the shift control unit 320 includes a plurality of cascaded triggers DFF, and the main output end of each trigger DFF constitutes a one-bit output of the shift control unit 320, assuming it is 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-bit outputs, namely sel_j[0], sel_j[1], sel_j[2], sel_j[3], and sel_j[4], which constitute a 5-bit selection signal sel_j (that is, the third control signal), and the selection signal sel_j is input to the control ends of the second multiplexer Mux-va and the third multiplexer Mux-vb.

[0137] The control ends of the second multiplexer Mux-va and the third multiplexer Mux-vb select the corresponding second signal SQUAR_DIS_Vj and the fourth signal distance_vj according to the selection signal sel_j.

[0138] When sel_j=5'b10000, it means that the distance from the first row of backlight partitions in the vertical direction is calculated at this time, the second multiplexer Mux-va selects: SUQAR_DIS_V0, and the third multiplexer Mux-vb selects: distance_v0;

[0139] When sel_j=5'b11000, it means that the distance to the second row of backlight partitions in the vertical direction 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 distance to the third row of backlight partitions in the vertical direction is calculated, 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 partitions is calculated, 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 distance to the fifth row of backlight subareas in the vertical direction is calculated at this time, the second multiplexer Mux-va selects: SUQAR_DIS_V4, and the third multiplexer Mux-vb selects: distance_v4.

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

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

[0145] For example, please refer to Figure 5 For a 5*5 neighborhood backlight partition, the fourth adder Add3 includes 3, wherein a third adder Add3 is used to calculate the sum of the squares of the distances between a current pixel and a target backlight partition, that is, of the two inputs of the third adder Add3, one is the square of the distance between the current pixel and the target backlight partition in the horizontal direction H, and the other is the square of the distance between the current pixel and the target backlight partition in the vertical direction V.

[0146] Please refer to Fig. 9 , Fig. 9Schematic diagram of the output result of the distance operation module in the horizontal distance operation circuit in 4lane mode. In 4lane mode, when pixel data is transmitted, 4 pixels are transmitted each time, that is, the distance between the current pixel and the adjacent previous pixel is the distance of 4 pixels. At this time, the horizontal distance operation circuit outputs the square of the distance between 4 pixels and a certain neighborhood backlight partition in the horizontal direction in each clock cycle, such as Fig. 9 As shown, the four distance squares output in the first clock cycle T1 are 24025, 24336, 24649, and 24964, respectively, and their square roots are 155, 156, 157, and 158, respectively. The four distance squares output in the second clock cycle T2 are 25281, 25600, 25921, and 26244, respectively, and their square roots are 159, 160, 161, and 162, respectively. Thereafter, the squares of the distances between the four pixels and the same neighborhood backlight partition in the horizontal direction are output in each clock cycle.

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

[0148] Step S101, obtaining pixel data of the current pixel;

[0149] Step S102, inputting the pixel data into the distance calculation circuit to obtain the sum of the squares of the distances between the current pixel and any neighboring backlight partition in the horizontal direction and the vertical direction;

[0150] Step S103: calculating the grayscale compensation value of the current pixel according to the sum of the squares of the distances.

[0151] The grayscale compensation method of the disclosed embodiment is applicable to the distance operation circuit as shown above. During the pixel data transmission process, the distance operation circuit can be used to calculate in real time the sum of the squares of the distances between the current pixel point and each neighboring backlight partition. The sum of the squares of the distances can be used for subsequent calculation of the grayscale compensation value of the current pixel point.

[0152] It can be understood 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, and the embodiment of the present disclosure does not improve it. The embodiment of the present disclosure only improves the specific method of obtaining the sum of the squares of the distances between the current pixel and the neighboring backlight partitions in the grayscale compensation method.

[0153] Obviously, the above embodiments of the present disclosure are merely examples for clearly illustrating the present disclosure, and are not limitations on the implementation methods of the present disclosure. For ordinary technicians in this field, other different forms of changes or modifications can be made on the basis of the above description. It is impossible to list all the implementation methods here. All obvious changes or modifications derived from the technical solution of the present disclosure are still within the protection scope of the present disclosure.

Claims

1. A distance calculation circuit, characterized in that: It includes a distance calculation module, the distance calculation module is used to calculate the square of the distance between the current pixel and the target backlight partition in the target direction, the target backlight partition is any neighborhood backlight partition of the current pixel, the target direction is the horizontal direction or the vertical direction, and the distance calculation module includes a first operator, a shifter, a second operator, a third adder and a register; The first operator includes two input terminals, one of which inputs the coordinates of a target pixel point in a current backlight partition in a target direction, and the other input 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, and the first operator is used to perform addition or subtraction operations on the signals input from the two input terminals to obtain a first distance value; The input end of the shifter is connected to the output end of the first operator, and the shifter is used to perform shift processing on the first distance value to obtain a second distance value, where the second distance value is twice the first distance value; The second operator comprises two input terminals, one of which is connected to the output terminal of the shifter, and the other is connected to a first signal, the first signal is a first value, and the second operator is used to perform addition or subtraction operations on the data at the two input terminals; The third adder includes two input terminals, one of which is connected to the output terminal of the register, and the other is connected to the output terminal of the second operator. The output terminal of the third adder is connected to the input terminal of the register.

2. The distance calculation circuit according to claim 1, characterized in that: The distance calculation module also 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 the second signal, the second input terminal is connected to the output terminal of the register, the control terminal is connected to the first control signal, 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 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 the backlight partition, and is at a second level when the current pixel does not cross the backlight partition.

3. The distance calculation circuit according to claim 2, characterized in that: The distance calculation module also includes: A first cross-zone identification unit, wherein the input end of the first cross-zone identification unit is connected to the pixel data, and the output end is connected to the control end of the first multiplexer, and is used to identify whether the current pixel point crosses the backlight partition, and output 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.

4. The distance calculation circuit according to claim 3, characterized in that: The first cross-zone identification unit includes a rising edge detection unit and an OR gate, the rising edge detection unit includes a trigger and an AND gate, the trigger 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, the clock signal input terminal is used to input a clock signal, the main output terminal is connected to one of the input terminals of the AND gate, 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 of the input terminals of the OR gate, the other input terminal of the OR gate is connected to the third signal, and 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 point crosses the backlight partition, and when the third signal is at a second level, it indicates that the current pixel point does not cross the backlight partition.

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

6. The distance calculation circuit according to claim 5, characterized in that: The neighborhood backlight partition of the current pixel point includes multiple rows of backlight partitions distributed in 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 operation circuit includes a vertical distance operation circuit, the vertical distance operation circuit includes multiple distance operation modules, each distance operation module corresponds to a row of backlight partitions or a row of sub-backlight partitions, wherein, in the distance operation module corresponding to the row backlight partition on the first side of the current backlight partition, the first operator and the second operator are adders, and in the distance operation module corresponding to the row backlight partition on the second side of the current backlight partition, the first operator and the second operator are subtractors, in the distance operation module corresponding to the row sub-backlight partition 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, and in the distance operation module corresponding to the row sub-backlight partition 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.

7. The distance calculation circuit according to claim 5, characterized in that: The neighborhood backlight partition of the current pixel point includes a plurality of rows of backlight partitions distributed in 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 operation circuit includes a vertical distance operation circuit, the vertical distance operation circuit includes the distance operation module and a time-sharing multiplexing control module, the first operator includes a first adder and a first subtractor, the second operator includes a second adder and a second subtractor, the time-sharing multiplexing control module is used to control the distance operation module to time-sharingly calculate the square of the distance between the current pixel point and each row of backlight partitions and each row of sub-backlight partitions in the vertical direction, wherein the time-sharing multiplexing control module controls the distance operation module to calculate the current pixel point When the square of the distance between the pixel point 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 operation module to calculate the square of the distance between the current pixel point 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 operation module to calculate the square of the distance between the current pixel point 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 point 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 point is located on the second side of the horizontal center line of the current backlight partition.

8. The distance calculation circuit according to claim 7, characterized in that: The time-division multiplexing control module comprises: A second cross-region identification unit, wherein an input end of the second cross-region identification unit is connected to the pixel data, and is used to identify whether the current pixel point crosses the backlight partition, and generate a second control signal according to the identification result and output it to the shift control unit; A shift control unit, the shift control unit comprising a plurality of cascaded flip-flops, the shift control unit comprising a clock signal input terminal and a data input terminal, the clock signal input terminal being connected to a clock signal, the data input terminal being connected to an output terminal of the second cross-region identification unit, and an output terminal of each flip-flop in the plurality of cascaded flip-flops forming a third control signal; a multiplexer unit, the multiplexer unit comprising a second multiplexer and a third multiplexer, the second multiplexer being used to select one path from the multiple second signals to be output to the second input terminal of the first multiplexer, the second multiplexer being used to select one path from the multiple fourth signals to be output to the other input terminal of the first operator, the fourth signal indicating the distance between the current backlight partition and the target backlight partition in the vertical direction, the control terminals of the second multiplexer and the third multiplexer being connected to 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 is used to store the square of the distance between the current pixel point and the corresponding row of backlight partitions in the vertical direction.

9. The distance calculation circuit according to claim 8, characterized in that: The distance operation circuit also includes multiple fourth adders. For any fourth adder, the fourth adder includes a first input end and a second input end. The first input end is connected to the output end of a distance operation module in the horizontal distance operation circuit, and the second input end is connected to the output end of a register in the shift register unit.

10. The distance calculation circuit according to claim 1, characterized in that: The first value is the square of the second value, and the second value is the number of data channels when the display panel transmits data.

11. A grayscale compensation method, characterized in that: The following steps are involved: Get the pixel data of the current pixel; Inputting the pixel data into the distance calculation circuit to obtain the sum of the squares of the distances between the current pixel and any neighboring backlight partition in the horizontal direction and the vertical direction; The grayscale compensation value of the current pixel is calculated according to the sum of the squares of the distances.

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