Method and device for dynamically expanding grayscale of LED display screen

Abstract

The present invention provides a method for dynamically expanding the grayscale of an LED display screen, comprising the following steps: decoding grayscale data input into a gamma table; adding a flag bit and preprocessing the grayscale data decoded from the gamma table according to a minimum precision n required for displaying low-gray data, wherein the flag bit is used to distinguish low-gray data from high-gray data; and expanding the preprocessed grayscale data into grayscale data with a bit width of m+n bits according to the flag bit, wherein m is the bit width of the gamma table; thereby, based on the original controller architecture, a flag bit is used to distinguish whether each light point belongs to high grayscale or low grayscale, thereby dynamically adjusting the required control accuracy, solving the problem that the low-gray segment LED brightness consistency cannot be solved by point-by-point correction, and realizing higher-precision control of the low-gray segment LED.

Description

Technical Field

[0001] The present invention relates to the field of LED display technology, and in particular to a method and system for dynamically expanding the grayscale of an LED display screen. Background Art

[0002] In recent years, LEDs have become the fundamental light-emitting device for a wide variety of lighting devices. In the field of LED displays, large-area displays composed of dot-matrix modules or pixel units constructed from LEDs have rapidly become mainstream flat-panel display products in just over a decade, thanks to their high reliability, long service life, strong environmental adaptability, high price-performance ratio, and low operating costs. They have been widely used in the information display field.

[0003] Traditional multi-channel constant-current LED driver chips often use pulse width modulation (PWM) for display control. By controlling the duration of the LEDs' on / off switching, different grayscale brightness levels can be achieved. The control system sends grayscale data to the driver chip, which then controls the LED's on / off switching based on the received grayscale data. The higher the grayscale data sent by the control system, the higher the grayscale level of the displayed image.

[0004] Figure 1 The following is a schematic diagram of LED display gamma decoding. According to the working principle of LED display, Figure 1 As shown, the controller decodes the grayscale data of the display screen sent by the video source through a gamma table and then sends it to the driver chip for processing or other image processing modules. Here, the highest grayscale after gamma decoding is 16 bits. The gamma curve after gamma decoding of the LED display is an exponential function. The existing gamma decoding solution is to send the decoded grayscale data to the LED driver IC or other image processing modules. This solution can only achieve a fixed grayscale (such as 16 bits), and the control accuracy of the low grayscale segment and the high grayscale segment is the same (both are 1 grayscale clock). Because a difference of 1 clock at low grayscale can cause a significant change in the displayed brightness, this solution results in insufficient brightness control accuracy for the low grayscale LEDs. When the low grayscale brightness of the light points is inconsistent, it is impossible to improve the consistency of the low grayscale of the light points through correction.

[0005] Another issue is that with the continuous advancement of display technology, the requirements for display screens are becoming increasingly demanding. Driver chips currently available on the market support 16+nbit (for example, 18-bit), but current control system architectures only support grayscale data sent at a maximum of 16 bits. Sending 18-bit grayscale data would not only require changes to the control system's top-level architecture but would also double the hardware storage resources.

[0006] Based on this, a new solution is needed. Summary of the Invention

[0007] The object of the present invention is to provide a method for dynamically expanding the grayscale of an LED display screen, so as to achieve dynamic grayscale expansion based on the original controller architecture.

[0008] An embodiment of the present invention provides a method for dynamically expanding the grayscale of an LED display screen, comprising the following steps:

[0009] Decode the grayscale data of the input gamma table;

[0010] Adding a flag and preprocessing the grayscale data decoded from the gamma table according to the minimum precision n required to display low grayscale data, wherein the flag is used to distinguish low grayscale data from high grayscale data; and

[0011] According to the flag bit, the pre-processed grayscale data is expanded to grayscale data with a bit width of m+n bits, where m is the bit width of the gamma table.

[0012] In the method for dynamically expanding the grayscale of an LED display provided by the present invention, the steps of adding a flag bit and preprocessing the grayscale data decoded from the gamma table according to the minimum precision n required for displaying low-gray data include:

[0013] When the grayscale data decoded from the gamma table is less than or equal to m-1-n bits, the decoded grayscale data is divided into low grayscale data and represented as grayscale data with 1 bit as flag bit 0, m-1-n bits as the integer part of the decoded grayscale data, and n bits as the decimal part of the decoded grayscale data;

[0014] When the grayscale data decoded from the gamma table is greater than m-1-n bits, the decoded grayscale data is divided into high grayscale data and represented as grayscale data with 1 bit as flag bit 1 and m-1 bit as the integer part of the decoded grayscale data.

[0015] In the method for dynamically expanding the grayscale of an LED display provided by the present invention, the step of expanding the pre-processed grayscale data into grayscale data with a width of m+n bits according to the flag bit includes:

[0016] When the flag bit is 0, the first n bits of the expanded grayscale data are 0, and the last m bits are the pre-processed grayscale data;

[0017] When the flag bit is 1, the first m bits of the expanded grayscale data are pre-processed grayscale data, and the last n bits are 0.

[0018] According to another aspect of the present invention, there is also provided a device capable of dynamically expanding the grayscale of an LED display screen, comprising:

[0019] A decoding module, used for decoding the grayscale data of the input gamma table;

[0020] a preprocessing module, configured to add a flag and preprocess the grayscale data decoded from the gamma table according to the minimum precision n required to display the low grayscale data, wherein the flag is used to distinguish between the low grayscale data and the high grayscale data; and

[0021] An expansion module is used to expand the preprocessed grayscale data into grayscale data with a width of m+n bits according to the flag bit, where m is the bit width of the gamma table.

[0022] In the device capable of dynamically expanding the grayscale of an LED display provided by the present invention, the pre-processing module includes:

[0023] a division unit for dividing the grayscale data decoded from the gamma table into low-gray data when the grayscale data decoded from the gamma table is less than or equal to m-1-n bits, and for dividing the grayscale data decoded from the gamma table into high-gray data when the grayscale data decoded from the gamma table is greater than m-1-n bits;

[0024] The processing unit is used to represent the grayscale data decoded as low-gray data as grayscale data with 1 bit as flag bit 0, m-1-n bits as the integer part of the decoded grayscale data, and n bits as the decimal part of the decoded grayscale data; and when the grayscale data decoded as high-gray data, it is represented as grayscale data with 1 bit as flag bit 1 and m-1 bits as the integer part of the decoded grayscale data.

[0025] In the device for dynamically expanding the grayscale of an LED display screen provided by the present invention, the expansion module is used to, when the flag bit is 0, the first n bits of the expanded grayscale data are 0, and the last m bits are the preprocessed grayscale data; when the flag bit is 1, the first m bits of the expanded grayscale data are the preprocessed grayscale data, and the last n bits are 0.

[0026] According to another aspect of the present invention, there is also provided a device for dynamically expanding the grayscale of an LED display screen, comprising at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the one processor, and the instructions are executed by the at least one processor so that the at least one processor executes the method for dynamically expanding the grayscale of an LED display screen as described above.

[0027] According to another aspect of the present invention, a non-transitory computer-readable storage medium is provided, wherein the non-transitory computer-readable storage medium stores computer instructions for causing a computer to execute the method for dynamically expanding the grayscale of an LED display screen as described above.

[0028] The implementation of the embodiments of the present invention has the following beneficial effects: the method for dynamically expanding the grayscale of an LED display screen provided by the present invention adds a flag bit for distinguishing between low-gray data and high-gray data to the grayscale data decoded by the gamma table and preprocesses it according to the minimum accuracy required for displaying low-gray data; then, according to the flag bit, the preprocessed grayscale data is expanded to the required bit width; thus, based on the original controller architecture (16-bit gamma table), a flag bit is used to distinguish whether each light point belongs to high-gray or low-gray, thereby dynamically adjusting the required control accuracy, solving the problem that the low-gray level cannot be corrected by point-by-point correction to solve the poor brightness consistency of LEDs, and achieving higher-precision control of low-gray segment LEDs. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0030] Figure 1 Shown is a schematic diagram of LED display gamma decoding;

[0031] Figure 2 FIG2 is a flow chart of a method for dynamically expanding the grayscale of an LED display screen provided by an embodiment of the present invention;

[0032] Figure 3 Shown Figure 2 The schematic diagram of step S20 shown;

[0033] Figure 4 Shown Figure 2 The schematic diagram of step S30 shown;

[0034] Figure 5 FIG2 is a schematic diagram of a device capable of dynamically expanding the grayscale of an LED display screen provided by another embodiment of the present invention;

[0035] Figure 6 This is a schematic diagram of the hardware structure of a device capable of dynamically expanding the grayscale of an LED display screen provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0036] To facilitate understanding of the present invention, the present invention will be described more fully below with reference to the accompanying drawings. The drawings illustrate exemplary embodiments of the present invention. However, the present invention may be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and comprehensive understanding of the present invention.

[0037] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in this specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0038] The general idea of ​​the present invention is: in view of the problem in the prior art that when the low-gray brightness of the lamp point is inconsistent, the consistency of the low-gray brightness of the lamp point cannot be improved by correction, and if the 16+nbit gamma table is directly implemented, the controller needs more storage and higher computing units. According to the minimum precision required for displaying the low-gray data, a flag bit is added to the grayscale data decoded by the gamma table to distinguish between low-gray data and high-gray data and pre-processed; then, according to the flag bit, the pre-processed grayscale data is expanded to the required bit width; thus, based on the original controller architecture (16-bit gamma table), a flag bit is used to distinguish whether each lamp point belongs to high-gray or low-gray, so as to dynamically adjust the required control accuracy, solve the problem that the low-gray brightness consistency of the LED cannot be solved by point-by-point correction, and achieve higher-precision control of the low-gray segment LED.

[0039] In order to better understand the above technical solution, the above technical solution will be described in detail below in conjunction with the drawings and specific implementation methods of the specification. It should be understood that the embodiments of the present invention and the specific features in the embodiments are detailed descriptions of the technical solution of the present application, rather than limitations on the technical solution of the present application. In the absence of conflict, the embodiments of the present invention and the technical features in the embodiments can be combined with each other.

[0040] Figure 2 FIG. 1 is a flow chart of a method for dynamically expanding the grayscale of an LED display screen provided by an embodiment of the present invention. Figure 2 As shown, the method for dynamically expanding the grayscale of an LED display provided by the present invention includes the following steps:

[0041] Step S10: Decode the grayscale data of the input gamma table.

[0042] Specifically, in one embodiment of the present invention, the grayscale data from the controller is first decoded using a gamma table with a bit width of m (e.g., 16 bits). Those skilled in the art will appreciate that the process of decoding grayscale data using a gamma table is prior art and will not be further described herein.

[0043] Step S20: adding a flag bit to the grayscale data decoded from the gamma table and performing pre-processing according to the minimum precision n required for displaying low-grayscale data.

[0044] Specifically, in one embodiment of the present invention, the minimum precision n required to display low-gray data, that is, the maximum precision control of the grayscale clock of 1 / 2 to the power of n, needs to match the highest precision that the LED driver IC can achieve. Generally, n is an integer less than 4.

[0045] Furthermore, in one embodiment of the present invention, for grayscale data decoded from the gamma table, when the grayscale data is less than or equal to m-1-n bits, the decoded grayscale data is divided into low grayscale data, and when the grayscale data is greater than m-1-n bits, the decoded grayscale data is divided into high grayscale data. For low grayscale data, the decoded grayscale data is represented as grayscale data with 1 bit as flag bit 0, m-1-n bits as the integer part of the decoded grayscale data, and n bits as the decimal part of the decoded grayscale data; for high grayscale data, the decoded grayscale data is divided into high grayscale data and represented as grayscale data with 1 bit as flag bit 1 and m-1 bits as the integer part of the decoded grayscale data.

[0046] like Figure 3 As shown in the figure, taking m=16 as an example, when the grayscale data obtained by gamma decoding is less than or equal to 15-n bits, it is considered as low-grayscale data and is represented as data with a 1-bit flag of 0, 15-n bits representing the integer part, and n bits representing the fractional part. When the grayscale data obtained by gamma decoding is greater than 15-n bits, it is considered as high-grayscale data and is represented as data with a 1-bit flag of 1 and 15 bits representing the integer part. In other words, the high-grayscale data discards the accuracy of the lowest integer bit. By adding the fractional part to the low-grayscale data, precise control of the low-grayscale accuracy can be achieved.

[0047] Step S30: Expand the pre-processed grayscale data into grayscale data with a bit width of m+n bits according to the flag bit, where m is the bit width of the gamma table.

[0048] Specifically, in one embodiment of the present invention, the added flag bit can be used to distinguish whether the grayscale data is low-grayscale data or high-grayscale data. For low-grayscale data, the first n bits of the expanded grayscale data are 0, and the last m bits are pre-processed grayscale data; while for high-grayscale data, the first m bits of the expanded grayscale data are pre-processed grayscale data, and the last n bits are 0. As a result, dynamic grayscale expansion can be achieved based on the original controller architecture (for example, a 16-bit gamma table) without increasing system hardware costs.

[0049] like Figure 4As shown in the figure, m = 16 is also used as an example. The data before expansion is recorded as data_in[15:0], and the data after expansion is recorded as data_out[15+n:0]. Identify the flag bit. If the flag bit = 0, the expansion method is data_out[15+n:0] = {n'b0, data_in[15:0]}; if the flag bit = 1, the expansion method is data_out[15+n:0] = {data_in[14:0], 1'b0, n'b0}.

[0050] Figure 5 FIG. 1 is a schematic diagram of a device for dynamically expanding the grayscale of an LED display screen provided by another embodiment of the present invention. Figure 5 As shown, the device for dynamically expanding the grayscale of an LED display provided by the present invention includes:

[0051] A decoding module 510 is used to decode the grayscale data of the input gamma table;

[0052] A pre-processing module 520 is configured to add a flag and pre-process the grayscale data decoded from the gamma table according to the minimum precision n required to display the low grayscale data, wherein the flag is used to distinguish between the low grayscale data and the high grayscale data; and

[0053] The expansion module 530 is configured to expand the pre-processed grayscale data into grayscale data with a width of m+n bits according to the flag bit, where m is the bit width of the gamma table.

[0054] Specifically, in one embodiment of the present invention, the pre-processing module 520 includes:

[0055] The division unit 5201 is configured to divide the grayscale data decoded from the gamma table into low grayscale data when the grayscale data decoded from the gamma table is less than or equal to m-1-n bits, and to divide the grayscale data decoded from the gamma table into high grayscale data when the grayscale data decoded from the gamma table is greater than m-1-n bits;

[0056] The processing unit 5202 is used to represent the grayscale data as low-gray data, with 1 bit as the flag bit 0, m-1-n bits as the integer part of the decoded grayscale data, and n bits as the decimal part of the decoded grayscale data; and when the decoded grayscale data is high-gray data, it is represented as grayscale data with 1 bit as the flag bit 1 and m-1 bit as the integer part of the decoded grayscale data.

[0057] Specifically, in one embodiment of the present invention, the expansion module 530 is used to, when the flag bit is 0, the first n bits of the expanded grayscale data are 0, and the last m bits are the preprocessed grayscale data; when the flag bit is 1, the first m bits of the expanded grayscale data are the preprocessed grayscale data, and the last n bits are 0.

[0058] The functions of the various functional modules described in the device embodiment of the present invention can be specifically implemented according to the method in the above method embodiment. The specific implementation process can refer to the relevant description of the above method embodiment and will not be repeated here.

[0059] It should be noted that the description of various modules above is divided into these modules for the purpose of clarity. However, in actual implementation, the boundaries of various modules may be vague. For example, any or all functional modules herein may share various hardware and / or software elements. For another example, any and / or all functional modules herein may be implemented in whole or in part by a shared processor executing software instructions. In addition, various software submodules executed by one or more processors may be shared between various software modules. Accordingly, unless explicitly required, the scope of the present invention is not limited by the mandatory boundaries between various hardware and / or software elements.

[0060] Figure 6 FIG. 1 is a schematic diagram of the hardware structure of a device for dynamically expanding the grayscale of an LED display screen provided by an embodiment of the present invention. Figure 6 As shown, the device includes one or more processors 61 and a memory 62. Figure 6 A processor 61 is taken as an example. The processor 61 and the memory 62 may be connected via a bus or other means. Figure 6 The bus connection is taken as an example.

[0061] The processor 61 may be a central processing unit (CPU). The processor 61 may also be other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, or a combination of the above chips. The general-purpose processor may be a microprocessor or any conventional processor.

[0062] The memory 62, as a non-transitory computer-readable storage medium, can be used to store non-transitory software programs, non-transitory computer executable programs, and modules, such as program instructions / modules corresponding to the method for dynamically expanding the grayscale of an LED display screen in the embodiment of the present invention. The processor 61 executes the non-transitory software programs, instructions, and modules stored in the memory 62 to execute various functional applications and data processing of the server, thereby implementing the method for dynamically expanding the grayscale of an LED display screen in the above embodiment.

[0063] The memory 62 may include a program storage area and a data storage area, wherein the program storage area may store an operating system and application programs required for at least one function; the data storage area may store data created using the device that can dynamically expand the grayscale of the LED display screen, etc. In addition, the memory 62 may include a high-speed random access memory, and may also include a non-volatile memory, such as at least one disk storage device, a flash memory device, or other non-volatile solid-state storage device. In some embodiments, the memory 62 may optionally include a memory remotely located relative to the processor 61, and these remote memories may be connected to the device that can dynamically expand the grayscale of the LED display screen via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0064] The one or more modules are stored in the memory 62 and, when executed by the one or more processors 61 , perform the above-mentioned method for dynamically expanding the grayscale of an LED display screen.

[0065] The above-mentioned product can execute the method provided by the embodiment of the present invention, and has the functional modules and beneficial effects corresponding to the execution method. The technical details not fully described in this embodiment can be found in the following. Figure 2 Related description of the embodiment shown.

[0066] An embodiment of the present invention further provides a non-transitory computer storage medium storing computer-executable instructions capable of executing the above-described method for dynamically expanding the grayscale of an LED display screen. The storage medium may be a magnetic disk, an optical disk, a read-only memory (ROM), a random access memory (RAM), a flash memory, a hard disk drive (HDD), or a solid-state drive (SSD); the storage medium may also include a combination of the aforementioned types of memory.

[0067] Those skilled in the art will appreciate that all or part of the processes in the above-described method embodiments can be implemented by instructing the relevant hardware through a computer program. The program can be stored in a computer-readable storage medium, and when executed, the program can include the processes in the above-described method embodiments. The storage medium can be a magnetic disk, an optical disk, a read-only memory (ROM), or a random access memory (RAM).

[0068] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention. Such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A method for dynamically expanding the grayscale of an LED display screen, characterized in that: The following steps are involved: Decode the grayscale data of the input gamma table; According to the minimum precision n required to display low-gray data, a flag is added to the grayscale data decoded from the gamma table and preprocessed, wherein the flag is used to distinguish low-gray data from high-gray data; as well as According to the flag bit, the pre-processed grayscale data is expanded to grayscale data with a bit width of m+n bits, where m is the bit width of the gamma table.

2. The method for dynamically expanding the grayscale of an LED display screen according to claim 1, wherein: According to the minimum precision n required to display low-gray data, the steps of adding flags and preprocessing the grayscale data decoded from the gamma table include: When the grayscale data decoded from the gamma table is less than or equal to m-1-n bits, the decoded grayscale data is divided into low grayscale data and represented as grayscale data with 1 bit as flag bit 0, m-1-n bits as the integer part of the decoded grayscale data, and n bits as the decimal part of the decoded grayscale data; When the grayscale data decoded from the gamma table is greater than m-1-n bits, the decoded grayscale data is divided into high grayscale data and represented as grayscale data with 1 bit as flag bit 1 and m-1 bit as the integer part of the decoded grayscale data.

3. The method for dynamically expanding the grayscale of an LED display screen according to claim 2, characterized in that: The step of expanding the preprocessed grayscale data into grayscale data with a width of m+n bits according to the flag bit includes: When the flag bit is 0, the first n bits of the expanded grayscale data are 0, and the last m bits are the pre-processed grayscale data; When the flag bit is 1, the first m bits of the expanded grayscale data are pre-processed grayscale data, and the last n bits are 0.

4. A device capable of dynamically expanding the grayscale of an LED display screen, characterized in that: include: A decoding module, used for decoding the grayscale data of the input gamma table; A preprocessing module, configured to add a flag and preprocess the grayscale data decoded from the gamma table according to the minimum precision n required to display low-gray data, wherein the flag is used to distinguish low-gray data from high-gray data; as well as The expansion module is used to expand the preprocessed grayscale data into grayscale data with a bit width of m+n bits according to the flag bit, wherein m is the bit width of the gamma table.

5. The device capable of dynamically expanding the grayscale of an LED display screen according to claim 4, characterized in that: The pre-processing module comprises: a division unit for dividing the grayscale data decoded from the gamma table into low-gray data when the grayscale data decoded from the gamma table is less than or equal to m-1-n bits, and for dividing the grayscale data decoded from the gamma table into high-gray data when the grayscale data decoded from the gamma table is greater than m-1-n bits; The processing unit is used to represent the grayscale data decoded as low-gray data as grayscale data with 1 bit as flag bit 0, m-1-n bits as the integer part of the decoded grayscale data, and n bits as the decimal part of the decoded grayscale data; and when the grayscale data decoded as high-gray data, it is represented as grayscale data with 1 bit as flag bit 1 and m-1 bits as the integer part of the decoded grayscale data.

6. The device capable of dynamically expanding the grayscale of an LED display screen according to claim 5, characterized in that: The expansion module is used to, when the flag bit is 0, the first n bits of the expanded grayscale data are 0, and the last m bits are the preprocessed grayscale data; when the flag bit is 1, the first m bits of the expanded grayscale data are the preprocessed grayscale data, and the last n bits are 0.

7. A device for dynamically expanding the grayscale of an LED display screen, characterized in that: The invention comprises at least one processor; and a memory in communication with the at least one processor; wherein the memory stores instructions executable by the one processor, and the instructions are executed by the at least one processor so that the at least one processor executes the method for dynamically expanding the grayscale of an LED display according to any one of claims 1 to 3.

8. A non-transitory computer-readable storage medium, characterized in that The non-transitory computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a computer to execute the method for dynamically expanding the grayscale of an LED display screen according to any one of claims 1 to 3.

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