Method and system for managing color space of multi-primary-color LED lamp with multiple lamp beads

Abstract

The invention discloses a color space management method and system for a multi-primary-color LED lamp with multiple lamp beads, and the method comprises the steps: collecting the spectral data of the maximum brightness of each LED lamp bead of the LED lamp at different colors, and calculating the tristimulus value of each lamp bead; a gray scale brightness curve of each lamp bead is collected, and a corresponding independent gray scale compensation table is generated; converting the target chromaticity coordinate into a CIE1931 physical coordinate system; constructing a linear programming equation set based on the color conversion coefficient, calculating a target coordinate maximum brightness PWM duty ratio of each lamp bead in combination with the tristimulus values, and obtaining a target PWM value of each lamp bead; based on the maximum power parameter and the total power limit value of each color channel of the LED lamp, performing target coordinate color rendering index optimization of each lamp bead by adopting a sequential quadratic programming algorithm in combination with a fitness-based target function to obtain an optimized PWM value; updating lamp storage parameters based on the optimized PWM value; according to the invention, the color management effect of the multi-primary-color LED lamp with multiple lamp beads is improved.

Description

Technical Field

[0001] The present application relates to the field of new lighting technologies, and particularly to a method and system for color consistency management of multi-color LED lamps with multiple lamp beads. Background Art

[0002] Existing stage lighting equipment generally uses multi-color LED lamps (such as four colors or more like RGBW) to achieve complex color rendering. However, due to individual differences in LED chips, limitations in the accuracy of spectral splitting and color separation processes, and assembly errors during the production process, there are significant color consistency defects in the finished lamps; specifically manifested as: there are obvious deviations in the color coordinates and brightness of the light emitted by different lamp beads within the same lamp under the same driving signal. Especially in the application scenario of single-controllable moving head lights, the color difference problem within the viewing angle is more prominent.

[0003] Although the current mainstream color management technologies on the market can calculate color parameters by collecting spectral data of all lamp beads of a single lamp, they do not distinguish the individual characteristics of single lamp beads and only perform color compensation for the whole lamp as an object, which easily leads to the phenomenon that the color temperature and color rendering index in different regions of the same lamp show non-uniform distribution. Therefore, there are defects in the poor color management effect of multi-color LED lamps and there is room for improvement. Summary of the Invention

[0004] In order to improve the color management effect of multi-color LED lamps with multiple lamp beads, the present application provides a color space management method and system for multi-color LED lamps with multiple lamp beads.

[0005] In the first aspect, the invention object of the present application is achieved by adopting the following technical solutions: A color space management method for multi-color LED lamps with multiple lamp beads, including: Collecting spectral data of the maximum brightness of each LED lamp bead of the LED lamp in different colors, calculating the tristimulus values of each lamp bead and storing them; Collecting the gray-scale brightness curve of each lamp bead through the DXM control signal, generating an independent gray-scale compensation table corresponding to each lamp bead; converting the target chromaticity coordinates into the CIE1931 physical coordinate system; constructing a linear programming equation set based on the color conversion coefficient, and calculating the PWM duty cycle of the maximum brightness of the target coordinates of each lamp bead in combination with the tristimulus values to obtain the target PWM value of each lamp bead; Based on the maximum power parameters of each color channel of the LED lamp and the total power limit value, using the sequential quadratic programming algorithm and combining the objective function based on fitness to optimize the color rendering index of the target coordinates of each lamp bead to obtain the optimized PWM value; Updating the lamp storage parameters of the LED lamp based on the optimized PWM value.

[0006] By adopting the above technical solution, the present application provides a color consistency management technical solution for multi-primary-color LED lamps with multiple lamp beads, which is different from the prior art that adopts overall color data acquisition and ignores the color differences between lamp beads in the same lamp. When there are color differences between different lamp beads in the same lamp, it is difficult to accurately perform color space management on multi-primary-color LED lamps with multiple lamp beads. Therefore, the present application adopts a technical solution of single lamp bead-level color correction plus dynamic optimization of color rendering index to improve the color management effect of multi-primary-color LED lamps with multiple lamp beads. Specifically, by independently collecting the tristimulus values (X, Y, Z) and grayscale brightness curves of each LED lamp bead, the inherent differences between single lamp beads are eliminated, the problem of viewing angle color difference between different lamp beads in the same lamp is solved, and the individual differences and viewing angle color difference phenomena are eliminated, which is significantly better than the correction method taking the whole lamp as a unit in the prior art. To ensure the full color space consistency of multi-primary-color LED lamps, the present application is based on linear programming correction in the CIE physical coordinate system, combined with the optimization of the main lamp bead of the target chromaticity coordinates (x, y). The deviation between the chromaticity coordinates of the lamp at any color mixing ratio and the target value is <1%, covering the full color space (such as the RGBWW four-primary-color mixing color gamut). At the same time, the sequential quadratic programming (SQP) algorithm is adopted to optimize the color rendering index under power limitation (such as P_max = 300W), which is beneficial to improving the power utilization rate. At the same time, through the optimized adjustment of the PWM value, the light decay and temperature drift compensation of each lamp bead can be realized, and the aging tracking and dynamic calibration of multi-primary-color LED lamp beads can be realized, which is beneficial to meeting the requirements of color consistency, color rendering performance and reliability in harsh scenarios such as stage lighting and film and television production.

[0007] In a preferred example of the present application: The method includes: Converting the target chromaticity coordinates into the CIE1931 physical coordinate system, and the conversion formula is: X / (X + Y + Z) = x, Y / (X + Y + Z) = y; Constructing a linear programming equation system, the target PWM value x of each lamp bead i : Wherein, X, Y, and Z are the tristimulus values XYZ values; x, y are the (x, y) in the CIE1931 physical coordinate system; i is the number of colors; x i is the PWM duty cycle of the LED (0 - 1), controlling the LED brightness output; N lamp is the total number of LED lamp beads in the lamp; A 1i 、A 2i are the chromaticity conversion coefficients of the lamp beads.

[0008] By adopting the above technical solution, the target chromaticity coordinates are converted into the CIE1931 physical coordinate system, which can accurately represent and control the color performance of LED lamps, so as to ensure the color consistency and accuracy in different application scenarios.

[0009] In a preferred example of the present application: The construction of the linear programming equation system includes: Converting the CIE1931 physical coordinate system (x, y) into a linear equation for constructing a constraint coefficient matrix: X - x*(X + Y + Z) = 0, Y - y*(X + Y + Z) = 0; Constructing the linear programming equation system: max Y l = ∑(Y i *x i ) ∑(x i *(X i -x*(X i +Y i +Z i ))) = 0 ∑(x i *(Y i -y*(X i +Y i +Z i ))) = 0 0 ≤ x i ≤ 1; where Y l is the maximum brightness under the chromaticity constraint; X i , Y i and Z i are the X, Y, and Z components of the tristimulus values of each color respectively; Based on the preset objective function, the linear programming equation is converted into the linear programming standard form applicable to LED lamps with multiple lamp beads.

[0010] By adopting the above technical solution, based on the constructed linear programming equation system and converting it into the standard form applicable to LED lamps with multiple lamp beads, it is possible to accurately calculate the optimal PWM value of each lamp bead mathematically, thereby realizing the fine control of the brightness and color output of the lamp; based on the optimization under the maximum brightness and chromaticity constraints, this application not only considers the requirements of color accuracy, but also pursues the maximum brightness output while meeting these requirements, improving the overall performance of LED lamps.

[0011] In a preferred example of the present application: The conversion of the linear programming equation into the linear programming standard form applicable to LED lamps with multiple lamp beads based on the preset objective function includes: Presetting the objective function Ztar is: min Z tar = -∑(C i *x i ), the negative sign indicates minimizing the negative contribution; where C i is the color brightness, directly using the Y component of the tristimulus values of each color.

[0012] By adopting the above technical solution, this application ensures that even under different operating conditions, the lamp can provide a consistent color output by minimizing the negative contribution (equivalent to maximizing color consistency), which is crucial for applications that require high color consistency (such as stage lights).

[0013] In a preferred example of this application: The sequence quadratic programming algorithm is combined with the fitness-based objective function to optimize the color rendering index of the target coordinates of each lamp bead, including: The sequence quadratic programming algorithm combined with the fitness-based objective function is: where f is the fitness-based objective function value; cri ra is the color rendering index Ra value of the current PWM output; W is the optimization weight; cri r9 is the red color rendering index R9 value of the current PWM output; penalty is the power overlimit penalty term; The power calculation formula is: p = ∑(pwm × color p ) where P is the total output power; pwm is the PWM duty cycle of each color channel; color p is the maximum power of each color channel.

[0014] By adopting the above technical solution, combining the SQP algorithm with the penalty term realizes the global optimum of color rendering, power consumption, and stability; specifically, adopting the sequence quadratic programming algorithm and combining it with the fitness-based objective function for optimization not only takes into account the importance of the color rendering index Ra and the red color rendering index R9, but also ensures that the total output power does not exceed the limit by introducing the power overlimit penalty term, which helps to improve the energy efficiency ratio of LED lamps, while ensuring color quality and avoiding the risk of overload; at the same time, through the power calculation formula, the power consumption of each color channel is accurately controlled, achieving the effect of energy conservation while ensuring color quality.

[0015] In a preferred example of this application: The calculation formula of the power overlimit penalty term is: penalty = max(0, P max - p / maxdiff ) Among them, max() is the function to return the maximum value; P max is the maximum allowable output power; max diff is the penalty factor, and a penalty is imposed when p is less than P max .

[0016] By adopting the above technical solution, it effectively prevents the total output power from exceeding the allowable maximum value, avoids hardware damage caused by overload, and can also optimize the working efficiency of the lamp, ensuring the best color performance and brightness output within the power limit range.

[0017] In a preferred example of this application: the calculation of the tristimulus values includes: Collecting the spectral power distribution of each lamp bead through a spectrometer; Calculating the XYZ tristimulus values based on the CIE1931 standard chromaticity observer function, and the formula is: Among them, k is the normalization constant; S(λ) represents the spectral power distribution of the LED lamp bead; is the color matching function.

[0018] By adopting the above technical solution, the spectral power distribution of each lamp bead is collected by a spectrometer, and the XYZ tristimulus values are calculated based on the CIE1931 standard chromaticity observer function to obtain an accurate color representation method, so as to facilitate accurately adjusting the brightness and color of each lamp bead according to the actual measurement data.

[0019] In the second aspect, the invention object of this application is achieved by adopting the following technical solution: A color space management system for a multi-primary-color LED lamp with multiple lamp beads, which is used to execute the color space management method for a multi-primary-color LED lamp with multiple lamp beads as described above. The system includes: A spectral data acquisition module, which is used to collect the spectral data of the maximum brightness of each LED lamp bead of the LED lamp in different colors and calculate the tristimulus values of each lamp bead; A grayscale brightness curve acquisition module, which obtains the grayscale brightness curve of each lamp bead through the DXM control signal and generates an independent grayscale compensation table; A chromaticity coordinate conversion module, which converts the target chromaticity coordinate into the CIE1931 physical coordinate system; A PWM duty cycle calculation module, which constructs a linear programming equation set based on the color conversion coefficient and calculates the target PWM value of each lamp bead in combination with the tristimulus values; The PWM value optimization module optimizes the target PWM value of each LED bead according to the maximum power parameter of the color channel of the LED lamp and the total power limit value, using the sequential quadratic programming algorithm and the fitness-based objective function to obtain the optimized PWM value; The parameter update module is used to update the storage parameters of the LED lamp based on the optimized PWM value.

[0020] By adopting the above technical solutions, from the spectral data acquisition to the optimization and update of the PWM value, the whole process of the color control of the LED lamp is covered; the PWM duty cycle calculation module constructs a linear programming equation set based on the color conversion coefficient and combines the tristimulus values to calculate the target PWM value of each LED bead, which can accurately adjust the brightness output of each LED bead to achieve the expected color effect; the PWM value optimization module takes into account the maximum power parameter of the color channel of the LED lamp and the total power limit value, and uses the sequential quadratic programming algorithm and the fitness-based objective function to optimize the target PWM value of each LED bead, which can maximize the overall performance of the lamp while meeting the color requirements and avoid the risk of overload.

[0021] In the third aspect, the invention object of the present application is realized by adopting the following technical solutions: A computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the above color space management method of the multi-bead multi-primary-color LED lamp are realized.

[0022] In the fourth aspect, the invention object of the present application is realized by adopting the following technical solutions: A computer program product includes a computer program / instructions, and when the computer program / instructions are executed by a processor, the steps of the above color space management method of the multi-bead multi-primary-color LED lamp are realized.

[0023] In summary, the present application includes at least one of the following beneficial technical effects: 1. Combining the tristimulus values to calculate the target PWM value of each LED bead can accurately adjust the brightness output of each LED bead to achieve the expected color effect; considering the maximum power parameter of the color channel of the LED lamp and the total power limit value, using the sequential quadratic programming algorithm and the fitness-based objective function to optimize the target PWM value of each LED bead can maximize the overall performance of the lamp while meeting the color requirements; 2. By introducing a power overlimit penalty term to ensure that the total output power does not exceed the limit, it helps to improve the energy efficiency ratio of the LED lamp, while ensuring the color quality and avoiding the risk of overload. Description of the Drawings

[0024] Figure 1It is a flowchart of a color space management method for a multi - color - bead multi - primary - color LED lamp in an embodiment of the present application; Figure 2 It is an example diagram of a multi - bead lamp in a multi - color - bead multi - primary - color LED lamp's color space management method before color optimization; Figure 3 It is an example diagram of a multi - bead lamp in a multi - color - bead multi - primary - color LED lamp's color space management method after color optimization; Figure 4 Is Figure 2 And Figure 3 After the color of the lamp beads is optimized, in Figure 2 It is an indication diagram with obvious optimization effect. Detailed implementation mode

[0025] The following further elaborates on the present application in conjunction with the attached drawings.

[0026] In an embodiment, as Figure 1 shown, the present application discloses a color space management method for a multi - color - bead multi - primary - color LED lamp, which specifically includes the following steps: S1: Collect the spectral data of the maximum brightness of each LED lamp bead in different colors of the LED lamp, calculate the tristimulus values of each lamp bead and store them.

[0027] In this embodiment, a spectrometer with a resolution ≥ 1nm and a wavelength range of 380 - 780nm is used. In a dark - room environment, the maximum driving current (such as 350mA) is applied to each LED lamp bead, and the spectral power distribution S(λ) within the wavelength range of 380 - 780nm is recorded.

[0028] Specifically, based on the CIE1931 standard colorimetric observer function, the XYZ tristimulus values are calculated. The formula is: Among them, k is the normalization constant; S(λ) represents the spectral power distribution of the LED lamp bead; is the color - matching function; λ is the wavelength. For example, when a spectrometer with a wavelength of 380 - 780nm is used, the calculation of the XYZ components of the XYZ tristimulus values is

[0029] Furthermore, the X i , Y i , Z i of each lamp bead are stored in the database, and a unique identification code (such as an SN number) is associated with each lamp bead.

[0030] S2: Acquire the grayscale brightness curve of each LED bead through the DXM control signal, and generate an independent grayscale compensation table for each LED bead.

[0031] In this embodiment, DMX is short for Digital Multiplex, which is a communication protocol standard mainly used for signal transmission between different devices in a stage lighting system. The DXM control signal is the control signal used by the lighting fixture controller to control the LED beads. The grayscale brightness of each color of LED is acquired according to the DMX value. 256-level grayscale control instructions (0 - 100% brightness) are sent through the DMX512 protocol, and the real-time brightness value of each LED bead is recorded. The non-linear brightness response is segmented and polynomially fitted (such as cubic spline interpolation) to generate the grayscale brightness curve. An ideal grayscale brightness model is set (such as linear growth or gamma = 2.2 correction), and then the grayscale compensation coefficient is calculated. For example, compensation coefficient = target grayscale brightness / current grayscale brightness curve value. Then, the compensation table (256 × 1 byte) for each LED bead is burned into the EEPROM of the lighting fixture driver chip.

[0032] S3: Convert the target chromaticity coordinates to the CIE1931 physical coordinate system; construct a linear programming equation set based on the color conversion coefficient, and calculate the PWM duty cycle of the maximum brightness of the target coordinates of each LED bead in combination with the tristimulus values to obtain the target PWM value of each LED bead.

[0033] In this embodiment, the calculation process of color consistency is as follows: First, convert the input DMX value into the CIE1931 xy physical coordinate according to the coordinate parameters of each color set in the lighting fixture; convert the target chromaticity coordinates to the CIE1931 physical coordinate system, and the conversion formula is: X / (X + Y + Z) = x, Y / (X + Y + Z) = y; For the constructed linear programming equation set, the target PWM value x of each LED bead i : where X, Y, and Z are the tristimulus values XYZ; x, y are the (x, y) in the CIE1931 physical coordinate system; i is the number of colors; x i is the PWM duty cycle (0 - 1) of the LED, controlling the LED brightness output; N lamp is the total number of LED beads in the lighting fixture; A 1i 、A 2i are the chromaticity conversion coefficients of the LED beads.

[0034] For example, for an RGB + WW four-color stage light, there are four coordinate parameters and four DMX values. The program inside the lamp traverses every two coordinate points respectively. If the ratio of the two coordinate points corresponding to DMX is 1 (the maximum value), the midpoint of the two coordinates is returned at this time. If the ratio is 1:0.5, the position of 0.75 closer to the maximum value is returned.

[0035] Specifically, the target chromaticity coordinates are converted to the CIE1931 physical coordinate system, and the conversion formula is: X / (X + Y + Z) = x, Y / (X + Y + Z) = y; The converted target chromaticity coordinates are substituted into the constructed linear programming equation system to obtain the returned duty cycle, and finally output to the LED lamp beads.

[0036] For the constructed linear programming equation system, the target PWM value x of each lamp bead i : Among them, X, Y, and Z are the tristimulus values XYZ; x, y are the (x, y) in the CIE1931 physical coordinate system; i is the number of colors; x i is the PWM duty cycle (0 - 1) of the LED, controlling the LED brightness output; N lamp is the total number of LED lamp beads in the lamp; A 1i 、A 2i are the chromaticity conversion coefficients of the lamp beads.

[0037] In this embodiment, the constructed linear programming equation system includes: Convert the CIE1931 physical coordinate system (x, y) into a linear equation for constructing the constraint coefficient matrix: X - x*(X + Y + Z) = 0, Y - y*(X + Y + Z) = 0; The constructed linear programming equation system is: max Y l = ∑(Y i *x i ) ∑(x i *(X i - x*(X i + Y i + Z i ))) = 0 ∑(x i *(Y i - y*(X i + Y i + Z i ))) = 0 0 ≤ x i ≤ 1; Among them, Yl Maximize the brightness while satisfying the chromaticity constraint; X i , Y i and Z i are the X, Y, and Z components of the color tristimulus values respectively.

[0038] Convert the linear programming equation into the standard form of linear programming applicable to LED luminaires with multiple lamp beads based on a preset objective function.

[0039] Specifically, converting the linear programming equation into the standard form of linear programming applicable to LED luminaires with multiple lamp beads based on a preset objective function includes: The preset objective function Z tar is: min Z tar = -∑(C i *x i ), and the negative sign indicates minimizing the negative contribution; which is equivalent to maximizing color consistency; where C i is the color brightness, and the Y component of the tristimulus value of each color is directly used.

[0040] S4: Based on the maximum power parameters of each color channel of the LED luminaire and the total power limit value, use the sequential quadratic programming algorithm combined with the fitness-based objective function to optimize the target coordinates and color rendering index of each lamp bead, and obtain the optimized PWM value.

[0041] In this embodiment, according to the required color temperature range, calculate the high color rendering index color temperature PWM of each lamp bead, that is, use the sequential quadratic programming algorithm (also known as the SQP algorithm) combined with the fitness-based objective function as: where f is the fitness-based objective function value; cri ra is the color rendering index Ra value of the current PWM output; cri r9 is the red color rendering index R9 value of the current PWM output; W is the optimization weight; penalty is the power overlimit penalty term.

[0042] The calculation formula for the power overlimit penalty term is: penalty = max(0, P max - p / max diff ) where max() returns the maximum value function; P max is the maximum allowable output power; max diff is the penalty factor, and a penalty is imposed when p is less than P max .

[0043] Exemplarily, the actual power of each color is input into the host computer of the lamp, and the output power needs to be limited.

[0044] Assume that in an RGBW four-color stage light: R = 60W, G = 120W, B = 120W, W = 200W. The total power is equal to the sum of the powers of all colors P max = 60 + 120 + 120 + 200 = 500W, the limited power = 300W, and the maximum allowable power redundancy error is equal to the total power minus the limited power, 500 - 300 = 200W.

[0045] The power calculation formula is: p = ∑(pwm × color p ) where P is the total output power; pwm is the PWM duty cycle of each color channel; color p is the maximum power of each color channel; if the finally obtained power is greater than the limited power, the penalty value penalty increases to limit the final output power within the required range.

[0046] S5: Update the lamp storage parameters of the LED lamp based on the optimized PWM value.

[0047] Specifically, write the optimized PWM value x i in the form of a 16-bit integer into the register of the drive IC (such as the address from 0x00 to 0x1F); the firmware update method is to batch burn the parameters to the controllers of multiple lamp beads through the I 2 C or SPI interface.

[0048] Refer to Figures 2 to 4 , Figure 3 is an example diagram of the effect obtained by optimizing the color space of a multi-color LED lamp with multiple lamp beads using the color space management method of the multi-color LED lamp with multiple lamp beads of the present application (i.e., after gray scale compensation, consistency calculation, and color rendering index optimization); Figure 2 is an example diagram of the color rendering of the lamp before color space optimization; for the convenience of observing the color space management effect of the present application; in Figure 4 , the present application uses arrows to indicate the lamp beads with obvious optimization effects compared in Figure 2 and Figure 3 ; Figure 4 is marked on the basis of Figure 2 ; the present application can eliminate individual differences through the gray scale compensation table and avoid the color patch problem of traditional batch calibration; at the same time, dynamically adjust the PWM value to ensure the total power.

[0049] Exemplarily, 3 RGB LEDs are mixed, the target chromaticity coordinates are (x = 0.32, y = 0.33), and the total power limit is 2W.

[0050] The data acquisition results before optimization are as follows: for the red LED: X = 12.5, Y = 4.2, Z = 0.8; for the green LED: X = 2.3, Y = 15.6, Z = 1.9; for the blue LED: X = 0.8, Y = 1.2, Z = 7.5.

[0051] The optimization result is: target PWM value: x red = 0.45, x green = 0.35, x blue = 0.20. The actual chromaticity: (x = 0.319, y = 0.331), total power 1.98W, Ra = 92, R9 = 85.

[0052] Before optimization: color difference Δu′v′ = 0.015, R9 = 68; after optimization, the color difference is reduced to 0.003 and R9 is increased by 25%.

[0053] It should be understood that the sequence numbers of the steps in the above embodiments do not mean the order of execution. The execution order of each process should be determined according to its function and internal logic, and should not constitute any limitation to the implementation process of the embodiments of the present application.

[0054] In one embodiment, a color space management system for a multi - bead multi - primary - color LED lamp is provided. The color space management system for the multi - bead multi - primary - color LED lamp corresponds to the color space management method for the multi - bead multi - primary - color LED lamp in the above embodiment.

[0055] The color space management system for a multi - bead multi - primary - color LED lamp includes a spectral data acquisition module, a grayscale brightness curve acquisition module, a chromaticity coordinate conversion module, a PWM duty cycle calculation module, a PWM value optimization module, and a parameter update module. The detailed descriptions of each functional module are as follows: The spectral data acquisition module is used to acquire the spectral data of the maximum brightness of each LED bead in the LED lamp in different colors and calculate the tristimulus values of each bead; The grayscale brightness curve acquisition module obtains the grayscale brightness curve of each bead through the DXM control signal and generates an independent grayscale compensation table; The chromaticity coordinate conversion module converts the target chromaticity coordinates into the CIE1931 physical coordinate system; The PWM duty cycle calculation module constructs a linear programming equation set based on the color conversion coefficient and calculates the target PWM value of each bead in combination with the tristimulus values; The PWM value optimization module optimizes the target PWM value of each bead according to the maximum power parameter of the color channel of the LED lamp and the total power limit value, using the sequential quadratic programming algorithm and the fitness - based objective function to obtain the optimized PWM value; A parameter update module, configured to update the stored parameters of the LED lamp based on the optimized PWM value.

[0056] For the specific limitations of the color space management system of the multi-primary-color LED lamp with multiple lamp beads, reference can be made to the limitations of the color space management method of the multi-primary-color LED lamp with multiple lamp beads in the above text, which will not be elaborated here; each module in the above color space management system of the multi-primary-color LED lamp with multiple lamp beads can be implemented in whole or in part by software, hardware, and their combinations; the above modules can be embedded in the processor of the computer device in hardware form or independent of it, or can be stored in the memory of the computer device in software form, so that the processor can call and execute the operations corresponding to each of the above modules.

[0057] In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the following steps are implemented: S1: Collect the spectral data of the maximum brightness of each LED lamp bead of the LED lamp in different colors, calculate the tristimulus values of each lamp bead and store them; S2: Collect the grayscale brightness curve of each lamp bead through the DXM control signal, and generate an independent grayscale compensation table corresponding to each lamp bead; S3: Convert the target chromaticity coordinates into the CIE1931 physical coordinate system; construct a linear programming equation set based on the color conversion coefficient, and calculate the target coordinate maximum brightness PWM duty cycle of each lamp bead in combination with the tristimulus values to obtain the target PWM value of each lamp bead; S4: Based on the maximum power parameters of each color channel of the LED lamp and the total power limit value, adopt the sequential quadratic programming algorithm and combine the fitness-based objective function to optimize the color rendering index of the target coordinates of each lamp bead to obtain the optimized PWM value; S5: Update the lamp storage parameters of the LED lamp based on the optimized PWM value.

[0058] Those of ordinary skill in the art can understand that all or part of the processes in the methods of the above embodiments can be completed by instructing relevant hardware through a computer program. The computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above methods. Among them, any reference to a memory, storage, database, or other medium used in the embodiments provided in this application can include non-volatile and / or volatile memories. Non-volatile memories can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memories can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in many forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), Rambus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and Rambus dynamic RAM (RDRAM), etc.

[0059] In one embodiment, in particular, according to the embodiments of the present invention, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, embodiments of the present invention include a computer program product including a computer program / instructions that, when executed by a processor, implement the steps of the color space management method for a multi-primary-color LED lamp with multiple light beads as described. In such an embodiment, the computer program can be downloaded and installed from a network through a communication module and / or installed from a removable medium. When the computer program is executed by a central processing unit (CPU), it performs various functions defined in the present invention.

[0060] Those skilled in the art can clearly understand that, for the convenience and brevity of description, only the above division of each functional unit and module is used as an example. In actual applications, the above functions can be allocated to different functional units and modules as needed, that is, the internal structure of the device is divided into different functional units or modules to complete all or part of the functions described above.

[0061] The above-described embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some of the features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should all be included in the protection scope of the present application.

Claims

1. A color space management method for a multi-primary color LED lamp with multiple lamp beads, characterized in that: include: Collect the spectrum data of the maximum brightness of each LED lamp bead in different colors of the LED lamp, calculate and store the tristimulus values ​​of each lamp bead; The grayscale brightness curve of each lamp bead is collected through the DXM control signal, and an independent grayscale compensation table corresponding to each lamp bead is generated; Convert the target chromaticity coordinates into the CIE1931 physical coordinate system; A linear programming equation group is constructed based on the color conversion coefficient, and the target coordinate maximum brightness PWM duty cycle of each lamp bead is calculated in combination with the three stimulus values ​​to obtain the target PWM value of each lamp bead; Based on the maximum power parameters of each color channel of the LED lamp and the total power limit value, the sequential quadratic programming algorithm is combined with the objective function based on fitness to optimize the target coordinate display index of each lamp bead and obtain the optimized PWM value; The lamp storage parameters of the LED lamp are updated based on the optimized PWM value.

2. The color space management method of a multi-primary color LED lamp with multiple lamp beads according to claim 1, characterized in that: The method comprises: The target chromaticity coordinates are converted into the CIE1931 physical coordinate system, and the conversion formula is: X / (X+Y+Z)=x, Y / (X+Y+Z)=y; The constructed linear programming equations, the target PWM value x of each lamp bead i : Among them, X, Y, Z are the tristimulus values ​​XYZ; x, y are the CIE1931 physical coordinate system (x, y); i is the number of colors; x i N is the PWM duty cycle of the LED (0-1), which controls the LED brightness output; lamp A is the total number of LED lamp beads in the lamp; 1i , A 2i It is the chromaticity conversion coefficient of the lamp bead.

3. The color space management method of a multi-primary color LED lamp with multiple lamp beads according to claim 2, characterized in that: The construction of the linear programming equations comprises: Convert the CIE1931 physical coordinate system (x, y) into a linear equation to construct the constraint coefficient matrix: Xx*(X+Y+Z)=0, Yy*(X+Y+Z)=0; Construct the linear programming system of equations: max Y l =∑(And i *x i ) ∑(x i *(X i -x*(X i +Y i +Z i )))=0 ∑(x i *(AND i -y*(X i +Y i +Z i )))=0 0≤x i ≤1； Among them, Y l To maximize the brightness under the chromaticity constraint; X i , Y i and Z i are the X, Y, and Z components of the three stimulus values ​​of each color; The linear programming equation is converted into a linear programming standard form suitable for a multi-lamp LED lamp based on a preset objective function.

4. The color space management method of a multi-primary color LED lamp with multiple lamp beads according to claim 3, characterized in that: The method of converting the linear programming equation into a linear programming standard form suitable for a multi-lamp LED lamp based on a preset objective function includes: Preset objective function Z tar is: min Z tar =-∑(C i *x i ), the negative sign indicates minimizing negative contributions; Among them, C i For color brightness, the tristimulus value Y component of each color is used directly.

5. The color space management method of a multi-primary color LED lamp with multiple lamp beads according to claim 1, characterized in that: The method of using a sequential quadratic programming algorithm combined with a fitness-based objective function to optimize the target coordinate display index of each lamp bead includes: The sequential quadratic programming algorithm is combined with the fitness-based objective function as follows: Among them, f is the objective function value based on fitness; cri ra is the color rendering index Ra value of the current PWM output; cri r9 is the red color rendering index R9 value of the current PWM output; W is the optimization weight; penalty is the power over-limit penalty item; The power calculation formula is: p=∑(pwm×color p ) Where P is the total output power; pwm is the PWM duty cycle of each color channel; color p is the maximum power of each color channel.

6. The color space management method of a multi-primary color LED lamp with multiple lamp beads according to claim 5, characterized in that: The calculation formula of the power overlimit penalty term is: penalty=max(0,P max -p / max diff ) Among them, max() returns the maximum value function; P max is the maximum output power allowed; max diff is the penalty factor, when p is less than P max Punishment is imposed when necessary.

7. The color space management method of a multi-primary color LED lamp with multiple lamp beads according to claim 5, characterized in that: The calculation of the tristimulus values ​​includes: The spectral power distribution of each lamp bead is collected through a spectrometer; The XYZ tristimulus values ​​are calculated based on the CIE1931 standard chromaticity observer function. The formula is: Where, k is a normalization constant; S(λ) represents the spectral power distribution of the LED lamp bead; is the color matching function.

8. The color space management system of multi-primary color LED lamps with multiple lamp beads is characterized by: A method for color space management of a multi-primary color LED lamp with multiple lamp beads as claimed in any one of claims 1 to 6, the system comprising: The spectrum data acquisition module is used to collect the spectrum data of the maximum brightness of each LED lamp bead in the LED lamp at different colors and calculate the three stimulus values ​​of each lamp bead; Grayscale brightness curve acquisition module obtains the grayscale brightness curve of each lamp bead through DXM control signal and generates an independent grayscale compensation table; Chromaticity coordinate conversion module, converting the target chromaticity coordinates into the CIE1931 physical coordinate system; The PWM duty cycle calculation module constructs a linear programming equation group based on the color conversion coefficient and calculates the target PWM value of each lamp bead in combination with the three stimulus values; The PWM value optimization module optimizes the target PWM value of each lamp bead using a sequential quadratic programming algorithm and a fitness-based objective function according to the maximum power parameters of the color channel and the total power limit of the LED lamp to obtain the optimized PWM value; A parameter updating module is used to update the stored parameters of the LED lamp based on the optimized PWM value.

9. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the steps of the color space management method of the multi-primary color LED lamp with multiple lamp beads as claimed in any one of claims 1 to 7 are implemented.

10. A computer program product comprising a computer program / instructions, characterized in that When the computer program / instruction is executed by a processor, the steps of the color space management method of the multi-primary color LED lamp with multiple lamp beads as described in any one of claims 1 to 7 are implemented.

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