Display screen gamut correction method and device, equipment and storage medium

Abstract

The application discloses a display screen color gamut correction method and device, equipment and a storage medium, and relates to the technical field of screen display. The method comprises the following steps: collecting screen spectrum data based on a multispectral camera, and synchronously collecting ambient spectrum; processing the screen spectrum data in real time through spectrum compression coding, and outputting compressed spectrum data; performing spectrum feature reconstruction based on the compressed spectrum data, and obtaining reconstructed spectrum; performing target color gamut mapping processing on the reconstructed spectrum, and outputting mapped spectrum; correcting the mapped spectrum based on the ambient spectrum to obtain a corrected target spectrum, and converting the corrected target spectrum into a driving signal. The application processes the ambient spectrum synchronously, accurately offsets the interference of the ambient light on the color gamut correction, guarantees the high accuracy of the reconstructed spectrum through low-loss spectrum compression reconstruction, and balances the real-time performance and the accuracy.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of screen display, in particular to a display screen gamut correction method and device, equipment and storage medium. BACKGROUND

[0002] In the field of professional display, the real-time and precision requirements of color gamut control for application scenarios such as stage splicing screen and indoor large display screen are extremely strict. Such display screens are often exposed to dynamic environmental light interference (such as stage follow-up light, natural light change), and color consistency needs to be ensured when multiple screens are spliced, and factors such as screen aging and temperature drift will cause dynamic deviation of color gamut characteristics.

[0003] The current mainstream technology relies on RGB three-color sensors combined with pre-calibration color gamut lookup table (LUT) to realize color management, or uses full-spectrum analysis technology for color gamut mapping. However, the traditional color gamut correction method ignores environmental light interference and does not synchronously collect environmental spectrum, and cannot quantify the real-time superposition effect of environmental light reflection on screen color (such as stage strong light leading to color temperature imbalance of spliced screen), resulting in serious deviation of color accuracy in dynamic scenes; the contradiction between spectral processing efficiency and precision is prominent, although full-spectrum analysis retains rich spectral information, the high-dimensional data processing algorithm load is too large, it is difficult to meet the real-time needs of high refresh rate spliced screen, if the data is compressed (such as JPEG), the key characteristics such as peak wavelength and half-width are lost, resulting in mapping distortion. These problems seriously restrict the ability of existing technology to realize high-precision real-time color gamut control in complex lighting, multi-screen cooperation and other scenes, directly affecting the color consistency and visual experience of large display screens.

[0004] Therefore, the color gamut correction method relying on screen spectral data or low-dimensional environmental data alone cannot realize high-precision, real-time color gamut control and display color accuracy in dynamic environments.

[0005] The above content is only used to assist in understanding the technical solutions of the present application, and does not represent the acknowledgement of the above content as prior art. SUMMARY

[0006] The main purpose of the present application is to provide a display screen gamut correction method, device, equipment and storage medium, which aims to solve the technical problem that high-precision, real-time color gamut control and display color accuracy cannot be realized in dynamic environments.

[0007] To achieve the above purpose, the present application provides a display screen gamut correction method, which comprises:

[0008] Collecting screen spectral data based on a multi-spectral camera, and synchronously collecting environmental spectrum;

[0009] Real-time processing the screen spectral data through spectral compression encoding, and outputting compressed spectral data;

[0010] reconstructing a spectrum feature based on the compressed spectrum data to obtain a reconstructed spectrum;

[0011] performing target color gamut mapping processing on the reconstructed spectrum to output a mapped spectrum;

[0012] correcting the mapped spectrum based on the ambient spectrum to obtain a corrected target spectrum, and converting the corrected target spectrum into a driving signal.

[0013] In an embodiment, the step of acquiring screen spectrum data based on a multi-spectrum camera and synchronously acquiring ambient spectrum data comprises:

[0014] sending a color block display instruction to a display screen to make the display screen display a standard color target;

[0015] acquiring screen spectrum data of the display screen under the standard color target by a multi-spectrum camera and obtaining a time stamp;

[0016] synchronously triggering an ambient light sensor acquisition instruction based on the time stamp to obtain an ambient spectrum.

[0017] In an embodiment, the step of processing the screen spectrum data in real time by spectrum compression encoding to output compressed spectrum data comprises:

[0018] preprocessing the screen spectrum data;

[0019] performing dimension reduction processing on the preprocessed screen spectrum data by a principal component analysis algorithm;

[0020] processing the dimension-reduced screen spectrum data by an adaptive quantization method to obtain quantized data;

[0021] encoding the quantized data to output compressed spectrum data.

[0022] In an embodiment, the step of reconstructing a spectrum feature based on the compressed spectrum data to obtain a reconstructed spectrum comprises:

[0023] decoding and dequantizing the compressed spectrum data to obtain dequantized data;

[0024] obtaining a reconstructed spectrum by a spectrum reconstruction model based on the dequantized data and a pre-stored basis vector matrix;

[0025] calculating a mean square error of the reconstructed spectrum and the original spectrum;

[0026] if the mean square error is less than a first preset threshold, outputting the reconstructed spectrum.

[0027] In an embodiment, the step of performing target color gamut mapping processing on the reconstructed spectrum to output a mapped spectrum comprises:

[0028] calculating an actual gamut boundary by an incremental convex hull based on the reconstructed spectrum;

[0029] comparing the actual gamut boundary with a pre-stored target gamut boundary to determine a pixel belonging region, the pixel belonging region including a super gamut region and an uncovered region;

[0030] determining a region mapping strategy based on the pixel belonging region, and obtaining a mapping spectrum by the corresponding region mapping strategy.

[0031] In an embodiment, the determining a region mapping strategy based on the pixel belonging region includes:

[0032] if the pixel belonging region is the super gamut region, adopting an absolute gamut mapping strategy of compressing saturation along a constant hue line to the target gamut boundary;

[0033] if the pixel belonging region is the uncovered region, adopting a gamut expansion or a substitute color selection strategy.

[0034] In an embodiment, the step of correcting the mapping spectrum based on the ambient spectrum to obtain a corrected target spectrum, and converting the corrected target spectrum into a driving signal includes:

[0035] calculating an ambient reflection spectrum based on the ambient spectrum and a pre-stored screen reflectivity;

[0036] obtaining a corrected target spectrum based on the ambient reflection spectrum and the mapping spectrum;

[0037] checking whether the corrected target spectrum is within the target gamut boundary, and adjusting the corrected target spectrum based on a region processing strategy;

[0038] discretizing the corrected target spectrum that passes the check, and calculating XYZ tristimulus values by a trapezoidal integration method;

[0039] real-time querying a pre-stored gamut mapping lookup table (LUT) based on the XYZ tristimulus values, and outputting corresponding driving signals.

[0040] In addition, to achieve the above object, the present application further provides a display screen gamut correction device, which includes:

[0041] a spectrum acquisition module, configured to acquire screen spectrum data based on a multi-spectrum camera, and synchronously acquire an ambient spectrum;

[0042] a spectrum compression module, configured to real-time process the screen spectrum data by spectrum compression coding, and output compressed spectrum data;

[0043] a spectrum reconstruction module, configured to reconstruct a spectrum feature based on the compressed spectrum data, to obtain a reconstructed spectrum;

[0044] a target color gamut mapping module, configured to perform target color gamut mapping processing on the reconstructed spectrum, to output a mapped spectrum;

[0045] a signal processing module, configured to correct the mapped spectrum based on the ambient spectrum to obtain a corrected target spectrum, and to convert the corrected target spectrum into a driving signal.

[0046] In addition, to achieve the above-mentioned purpose, the present application also provides a display screen color gamut correction device, which comprises a memory, a processor, and a computer program stored in the memory and executable on the processor, and the computer program is configured to implement the steps of the display screen color gamut correction method as described above.

[0047] In addition, to achieve the above-mentioned purpose, the present application also provides a storage medium, which is a computer-readable storage medium, and the storage medium stores a computer program, and the computer program is executed by a processor to implement the steps of the display screen color gamut correction method as described above.

[0048] In addition, to achieve the above-mentioned purpose, the present application also provides a computer program product, which comprises a computer program, and the computer program is executed by a processor to implement the steps of the display screen color gamut correction method as described above.

[0049] The one or more technical solutions provided by the present application have at least the following technical effects:

[0050] The present application acquires screen spectrum data based on a multi-spectrum camera, and synchronously acquires ambient spectrum; the screen spectrum data is processed in real time through spectrum compression coding to output compressed spectrum data; spectrum feature reconstruction is performed based on the compressed spectrum data to obtain a reconstructed spectrum; target color gamut mapping processing is performed on the reconstructed spectrum to output a mapped spectrum; the mapped spectrum is corrected based on the ambient spectrum to obtain a corrected target spectrum, and the corrected target spectrum is converted into a driving signal, thereby solving the technical problem that high-precision and real-time color gamut control and display color accuracy cannot be achieved in a dynamic environment. The present application processes by synchronously acquiring ambient spectrum, accurately offsets the interference of ambient light on color gamut correction, guarantees high-precision of the reconstructed spectrum through low-loss spectrum compression reconstruction, and achieves a balance between real-time performance and accuracy. BRIEF DESCRIPTION OF DRAWINGS

[0051] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the application.

[0052] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the accompanying drawings needed to be used in the embodiments or prior art description will be briefly introduced as follows. Obviously, the drawings can also provide further understanding of the prior art for those of ordinary skill in the art without any creative effort.

[0053] Figure 1 The flowchart provided by the display screen color gamut correction method embodiment one of the present application;

[0054] Figure 2 The flowchart provided by the display screen color gamut correction method embodiment two of the present application;

[0055] Figure 3 The flowchart provided by the display screen color gamut correction method embodiment three of the present application;

[0056] Figure 4 The flowchart provided by the display screen color gamut correction method embodiment four of the present application;

[0057] Figure 5 The module structure diagram of the display screen color gamut correction device of the present application embodiment;

[0058] Figure 6 The device structure diagram of the hardware running environment involved in the display screen color gamut correction method in the present application embodiment.

[0059] The purpose of the present application, the function characteristics and the advantages will be further explained by combining the embodiments with the drawings. DETAILED DESCRIPTION

[0060] It should be understood that the specific embodiments described herein are only used to explain the technical solutions of the present application, and are not used to limit the present application.

[0061] In order to better understand the technical solutions of the present application, the following will be described in detail in combination with the drawings of the specification and the specific embodiments.

[0062] The prior art cannot realize high-precision, real-time color gamut control and display color accuracy in dynamic environment.

[0063] The application provides a solution, based on a multispectral camera to collect screen spectral data and synchronously collect ambient spectrum; through spectral compression coding to process the screen spectral data in real time, output compressed spectral data; based on the compressed spectral data to reconstruct spectral features, obtain reconstructed spectrum; perform target color gamut mapping processing on the reconstructed spectrum, output mapped spectrum; based on the ambient spectrum to correct the mapped spectrum to obtain corrected target spectrum, convert the corrected target spectrum into driving signal. The application processes through synchronous collection of ambient spectrum, accurately offsets the interference of ambient light on color gamut correction, guarantees high accuracy of reconstructed spectrum through low-loss spectral compression reconstruction, and balances real-time performance and accuracy.

[0064] Based on this, the application embodiment provides a display screen color gamut correction method, referring to Figure 1 , Figure 1 FIG. 1 is a flowchart of a first embodiment of the display screen color gamut correction method of the application.

[0065] In this embodiment, the display screen color gamut correction method comprises steps S10-S50:

[0066] Step S10, based on a multispectral camera to collect screen spectral data and synchronously collect ambient spectrum;

[0067] It should be noted that the multispectral camera refers to a camera capable of capturing spectral information of multiple visible light bands (usually 400-700 nm, 10-20 nm resolution), which realizes multi-band imaging through narrow-band filtering or spectral technology, and can more accurately obtain the spectral power distribution (SPD) of the screen compared with an RGB camera (only capturing 3 bands of red, green and blue); the screen spectral data refers to the spectral power distribution data of the display screen when displaying specific content (such as a standard color target), which reflects the inherent color characteristics of the screen; synchronous collection refers to starting the ambient light spectrum data collection of the ambient light sensor at the same time and the same angle as the screen spectral data collection, to ensure the time and space correlation of the two; the ambient spectrum refers to the spectral power distribution data of the ambient light, which reflects the radiation intensity of the ambient light at each band (such as the spectral characteristics of sunlight and indoor light). The high-resolution spectral data of the screen captured by the multispectral camera retains the spectral details, and the correlation of the ambient spectrum data and the screen spectral data is ensured through the synchronous mechanism, i.e., accurate screen spectral data and synchronous ambient spectral data are obtained, to provide accurate input for offsetting the influence of ambient light reflection.

[0068] In a specific embodiment, during the construction of the stage splicing screen, the multispectral camera is installed in front of the screen and level with the eyes of the audience, and the ambient light sensor is installed around the splicing screen. When the screen displays white, the multispectral camera collects the white spectral data (such as 6500K SPD) of the screen, and at the same time, the ambient light sensor is triggered by the GPIO signal to collect the spectral data (such as 5000K SPD) of the splicing screen around the stage. The time difference between the two is less than 1ms, ensuring the relevance of the data. By reducing the amount of spectral data, the spectral data is suitable for real-time transmission and processing, while retaining the key features of the spectrum, avoiding the processing errors caused by the loss of spectral features in traditional compression methods such as JPEG, and achieving a balance between data volume and accuracy.

[0069] Step S20, real-time processing of the screen spectral data by spectral compression encoding, outputting compressed spectral data;

[0070] It should be noted that spectral compression encoding refers to the process of dimensionality reduction, quantization and encoding of screen spectral data, with the purpose of reducing data volume while retaining key spectral features such as peak wavelength and half-width; real-time processing refers to processing time less than the refresh period of the display screen, such as 8.3ms under a 120Hz refresh rate, ensuring that data processing does not affect display effects; compressed spectral data refers to spectral data after compression and encoding, which has a much smaller data volume than original spectral data but retains most of the spectral features.

[0071] Step S30, reconstructing spectral features based on the compressed spectral data to obtain reconstructed spectrum;

[0072] It should be noted that spectral feature reconstruction refers to the process of restoring compressed spectral data to original spectral data, including decoding, dequantization and reconstruction based on basis vectors; reconstructed spectrum refers to spectral data after spectral feature reconstruction, which has highly consistent spectral features with original spectral data, making the mean square error (MSE) between the two less than a preset error threshold.

[0073] In a possible embodiment, spectral feature reconstruction includes the following sub-steps: 1) decoding: Huffman decoding of compressed spectral data to obtain quantized principal component coefficients; 2) dequantization: dequantization of the quantized coefficients to obtain original principal component coefficients; 3) reconstruction: linear combination of principal component coefficients with pre-stored PCA basis vectors to obtain reconstructed spectrum.

[0074] Step S40, target color gamut mapping processing of the reconstructed spectrum, outputting mapped spectrum;

[0075] It should be noted that the target color gamut mapping processing refers to the process of mapping the reconstructed spectrum to the target color gamut (such as sRGB, DCI-P3), including color gamut boundary calculation, region judgment and mapping strategy selection; the mapped spectrum refers to the spectrum data after target color gamut mapping processing, whose spectral characteristics meet the requirements of the target color gamut, for example, the chroma error ΔE is within the error range. The actual color gamut boundary of the reconstructed spectrum is calculated by the incremental convex hull algorithm, the region to which it belongs is judged, such as the super color gamut region, the uncovered region, the normal region, and the corresponding mapping strategy is adopted, such as absolute color gamut mapping, color gamut expansion, substitute color selection, to map the reconstructed spectrum to the target color gamut, so that the display color meets the target requirements.

[0076] Step S50, based on the ambient spectrum, the mapping spectrum is corrected to obtain a corrected target spectrum, and the corrected target spectrum is converted into a driving signal.

[0077] It should be noted that the ambient spectrum correction refers to the correction of the mapping spectrum based on the ambient spectrum data to offset the influence of ambient light reflection; the corrected target spectrum refers to the mapping spectrum after ambient spectrum correction, whose spectral characteristics meet the requirements of the target color gamut and offset the influence of ambient light reflection; the driving signal refers to the signal used to control the display screen to emit light, such as the digital driving value (0-1023) of the RGB sub-pixel.

[0078] The above-mentioned display screen color gamut correction method, based on the multi-spectral camera, acquires screen spectrum data and synchronously acquires ambient spectrum; the screen spectrum data is processed in real time by spectral compression coding, and compressed spectrum data is output; the spectral characteristics are reconstructed based on the compressed spectrum data, and a reconstructed spectrum is obtained; the reconstructed spectrum is subjected to target color gamut mapping processing, and a mapped spectrum is output; the mapped spectrum is corrected based on the ambient spectrum to obtain a corrected target spectrum, and the corrected target spectrum is converted into a driving signal. In a dynamic environment, such as ambient light transformation and scene switching, through accurate data acquisition, processing and correction at the spectral level, the balance between accuracy and real-time is achieved through compression and reconstruction, the efficiency of data processing is embodied, the regional strategy realizes the strict fitting of the target color gamut, the ambient light interference is offset through wave band-by-wave band correction, the real-time driving signal ensures the color accuracy stability in dynamic scenes, and stable output of the display screen is realized, so that it meets the color of the target color gamut.

[0079] Further, the step S10 "based on the multi-spectral camera, acquires screen spectrum data and synchronously acquires ambient spectrum" is further refined, including:

[0080] Step A201, a color block display instruction is sent to the display screen, so that the display screen displays a standard color target;

[0081] Step A202, screen spectrum data of the display screen under the standard color target is acquired by the multi-spectral camera and a time stamp is obtained;

[0082] Step A203, based on the timestamp, synchronously trigger the ambient light sensor to collect instructions, and obtain the ambient light spectrum.

[0083] It should be noted that in the present embodiment, the standard color target refers to a display pattern containing a plurality of standard colors (such as the 24-color card specified in ISO 12646, a full white field, and a gradual gray scale), and the purpose is to cover all hues, saturations, and luminances of the target color gamut (such as the 24-color card containing red, green, blue, yellow, and other basic colors, the full white field for calibrating luminance, and the gradual gray scale for calibrating contrast), to ensure that the collected screen spectrum data can fully reflect the inherent color characteristics of the screen; the screen spectrum data refers to the spectral power distribution (SPD) of the display screen when displaying the standard color target, specifically including the radiation intensity of the 400-700nm visible light band (such as 16 bands, 10nm resolution), as the input of the core basic data for subsequent color gamut mapping and ambient correction; the timestamp refers to the time marker when the multispectral camera collects the screen spectrum data, such as Unix timestamp or GPS timestamp, for realizing the synchronization of ambient light collection; the ambient spectrum refers to the spectral power distribution of the ambient light collected by the ambient light sensor, and its collection position needs to simulate the user's perspective, such as 45° in front of the screen, the height being level with the eyes, etc., to ensure the spatial correlation with the screen spectrum data, so as to accurately reflect the interference of ambient light on human eye color perception.

[0084] For example, the system sends a color block display instruction to the display screen to make the display screen display the standard color target, which aims to provide a stable and repeatable collection object for the multispectral camera, to avoid fluctuations in the spectral data caused by changes in the display content; then the multispectral camera is triggered to collect the screen spectrum data and obtain the timestamp, to ensure the timeliness of the data, such as synchronization with the display screen refresh time; then the ambient light sensor is synchronously triggered based on the timestamp to obtain the ambient spectrum at the same time, to realize the time correlation between the screen spectrum data and the ambient spectrum data, so that the time deviation is less than 1ms. It can be seen that the standard color target ensures the comprehensiveness (covering the target color gamut) and accuracy (reflecting the inherent characteristics of the screen) of the screen spectrum data, and the timestamp synchronization ensures the correlation (at the same time, at the same perspective) between the ambient spectrum data and the screen spectrum data, thereby laying a foundation for subsequent offsetting the influence of ambient light reflection and realizing high-precision color gamut calibration.

[0085] In one possible implementation, the standard color target is selected as a 24-color card (ISO 12646) containing colors covering the main hues (e.g., red, green, blue, yellow, cyan, magenta) of the target color gamut, ensuring that the collected screen spectral data can comprehensively reflect the characteristics of the screen under different hues; the triggering mode of the multi-spectral camera is a hardware trigger (e.g., a GPIO signal), that is, the system sends a collection instruction to the multi-spectral camera through a hardware circuit, ensuring that the collection time is synchronized with the refresh time (e.g., a VSync signal) of the display screen, avoiding the inconsistency between the spectral data and the display content due to software delay; the ambient light sensor is a multi-spectral radiometer (e.g., Konica Minolta CS-2000), which has the same spectral resolution (10 nm) as the multi-spectral camera, ensuring that the wavelength range of the ambient spectral data matches that of the screen spectral data (400-700 nm), so as to realize the ambient light correction in each wavelength band.

[0086] In another possible implementation, the standard color target can be selected as a full-color gamut gradient pattern (e.g., a linear gradient from red to purple), which aims to more accurately capture the spectral characteristics (e.g., spectral peak shift when the saturation changes) of the screen under continuous hues, thereby improving the accuracy of subsequent color gamut mapping.

[0087] Further, with reference to Figure 2 , the second embodiment of the image display method of the present application provides a flowchart, based on the above Figure 2 embodiment, the step S20 "real-time processing of the screen spectral data through spectral compression encoding, and output of compressed spectral data" is further refined, including steps A301-A304:

[0088] Step A301, preprocessing of the screen spectral data;

[0089] Step A302, dimension reduction processing of the preprocessed screen spectral data through a principal component analysis algorithm;

[0090] Step A303, processing of the dimension-reduced screen spectral data through an adaptive quantization method to obtain quantized data;

[0091] Step A304, encoding of the quantized data, and output of compressed spectral data.

[0092] It should be noted that in the embodiment, the preprocessing refers to the process of radiation correction and band alignment of screen spectral data, wherein the radiation correction includes dark frame subtraction, such as collecting dark field data in the absence of light to eliminate sensor dark current error and flat field correction, such as collecting uniform light field data to eliminate lens distortion, sensor response non-uniformity and other flat field errors, the purpose is to improve the accuracy of spectral data; the band alignment is to adjust the band range of the screen spectral data, so that it is completely consistent with the band of the ambient spectral data, and ensure the consistency of the subsequent environmental correction. Principal component analysis (PCA) is a high-dimensional data dimension reduction method, which generates basis vectors by offline training screen inherent spectral characteristics (such as sub-pixel SPD), linearly transforms the 16-band preprocessed spectral data into 3-5 principal component coefficients, and retains most of the spectral variance, that is, the key features such as peak wavelength and half-width, the purpose is to reduce the data amount while retaining the spectral essential information, and avoid the algorithm bottleneck caused by high-dimensional data. Adaptive quantization refers to allocating quantization bits according to the variance of the principal component coefficients, for example, the first two principal components (covering >90% variance) are quantized by 10-bit μ-law (fine step, retaining details), and the third principal component (covering about 9% variance) is quantized by 8-bit μ-law (coarse step, saving bits), the purpose is to prioritize key information under limited bits, and avoid the loss of key features caused by uniform quantization. Encoding is a redundant compression of the quantized principal component coefficients, in the embodiment, Huffman coding is used, the probability distribution of the principal component coefficients is statistically analyzed offline, an encoding table is generated, and the coefficients are encoded in real time using the table, further reducing the data amount.

[0093] The embodiment realizes real-time processing of "low data amount and high spectral feature retention" through the four-step cooperation of "preprocessing → PCA dimension reduction → adaptive quantization → encoding". The error problem of subsequent color gamut mapping caused by the loss of spectral features in traditional compression methods (such as JPEG) is solved, and the compressed spectral data can still accurately reflect the inherent color characteristics of the screen, laying a foundation for subsequent environmental correction and drive signal generation.

[0094] In a possible implementation, the preprocessing adopts a "dark frame + flat field" combination correction: dark field (screen off) and full white field (maximum brightness) data are collected before the system is shipped, and in real-time processing, the correction is performed using the formula "original data = (original data - dark frame) / flat field" to eliminate hardware errors; the PCA dimension reduction uses the base vector offline trained, such as a 16x3 matrix, which is stored in the BRAM of the FPGA, and the matrix multiplication is implemented through the DSP slice to convert the 16-band data into 3 principal component coefficients; the adaptive quantization uses the μ-law quantization (μ=255), and the first two coefficients are quantized to 10 bits, and the third coefficient is quantized to 8 bits, which is consistent with the visual characteristics of the human eye to coarse quantization of small signals and fine quantization of large signals; the encoding uses the Huffman encoding IP core (Xilinx), the encoding table is generated offline, and the quantized coefficients are encoded using the encoding table in real-time processing to output the compressed spectral data.

[0095] Further, the step S30 "reconstructing a spectral feature based on the compressed spectral data to obtain a reconstructed spectrum" is further refined, including:

[0096] Step A401, decoding and dequantizing the compressed spectral data to obtain dequantized data;

[0097] Step A402, obtaining a reconstructed spectrum through a spectral reconstruction model based on the dequantized data and a pre-stored base vector matrix;

[0098] Step A403, calculating a mean square error between the reconstructed spectrum and the original spectrum;

[0099] Step A404, if the mean square error is less than a first preset threshold, outputting the reconstructed spectrum.

[0100] It should be noted that in the present embodiment, the compressed spectral data refers to the principal component coefficient data output by step S20 after Huffman coding, which contains 3-5 quantized principal component coefficients and is a low-dimensional compressed representation of the screen spectral data; decoding refers to variable-length decoding of the compressed spectral data using the offline-generated Huffman coding table (based on the probability distribution of the principal component coefficients) to restore the quantized principal component coefficients, with the purpose of eliminating the redundancy introduced by coding and restoring the coefficient structure before quantization; and dequantization is to restore the details lost in the quantization process through the μ-law dequantization formula, to ensure the accuracy of the principal component coefficients. The pre-stored basis vector matrix is an offline-trained 16x3 matrix (16 bands, 3 principal components), with each column vector corresponding to a principal component basis, which is generated by collecting screen sub-pixel inherent spectral characteristics (such as SPD of red, green, and blue sub-pixels), Gamma curve, etc., using the PCA algorithm, covering more than 99% of the spectral variance, and stored in the BRAM of the FPGA for real-time spectral reconstruction; the spectral reconstruction model is a linear combination model, i.e., the reconstructed spectrum is equal to the product of the dequantized principal component coefficients and the basis vector matrix, with the purpose of restoring the low-dimensional principal component coefficients to the high-dimensional spectral power distribution and accurately reflecting the screen's light-emitting characteristics. The mean square error (MSE) refers to the average of the square of the difference between the reconstructed spectrum and the original spectrum (pre-processed screen spectral data), which is used to measure the accuracy of the reconstructed spectrum; the first preset threshold is determined offline through a large number of tests, which corresponds to the chroma error threshold ΔE of the reconstructed spectrum and the original spectrum, stored in the BRAM of the FPGA, and can be adjusted online through the JTAG interface, such as adjusting the first preset threshold according to the screen aging condition.

[0101] The present embodiment realizes low-loss spectral "compression-reconstruction" through the technical closed loop of "decoding → dequantization → reconstruction → verification", solves the color gamut mapping error problem caused by the loss of spectral characteristics in traditional compression methods (such as JPEG), and ensures the accuracy of subsequent target color gamut mapping and ambient spectrum correction. Among them, the offline training of the basis vector matrix needs to cover the inherent spectral characteristics of the screen (such as sub-pixel SPD, Gamma curve), to ensure that the reconstructed spectrum can accurately reflect the screen's light-emitting characteristics; the MSE accuracy verification can avoid errors in the compression and decoding process, such as the deviation of the reconstructed spectrum caused by the error of Huffman coding, to ensure that the output reconstructed spectrum meets the display requirements of the display screen.

[0102] In a possible implementation, the decoding employs a Huffman decoding IP core of Xilinx, an encoding table (based on the probability distribution of principal component coefficients) is generated offline, and the IP core is used to decode the compressed spectral data in real time; the dequantization employs a combination logic to realize μ-law dequantization, 10-bit quantized coefficients are dequantized, and floating-point (32-bit) principal component coefficients are output; the spectral reconstruction model employs a DSP slice to realize matrix multiplication (dequantized coefficients x basis vector matrix), each DSP slice processes the product of one principal component coefficient and a basis vector, and three coefficients require three DSP slices; the MSE calculation employs a combination logic to realize the difference square, accumulation, and averaging of the reconstructed spectrum and the original spectrum on a waveband basis; and the first preset threshold is stored in the BRAM of the FPGA and can be adjusted online through the JTAG interface.

[0103] Further, referring to Figure 3 , the third embodiment of the image display method provides a flowchart, based on the above Figure 3 embodiment, the step S40 "performing target color gamut mapping processing on the reconstructed spectrum" is further refined, including steps A501-A503:

[0104] Step A501, obtaining an actual color gamut boundary through incremental convex hull calculation based on the reconstructed spectrum;

[0105] Step A502, comparing the actual color gamut boundary with a pre-stored target color gamut boundary to determine a pixel belonging area, the pixel belonging area including a super color gamut area and an uncovered area;

[0106] Step A503, determining a region mapping strategy based on the pixel belonging area, and obtaining a mapping spectrum through the corresponding region mapping strategy.

[0107] It should be noted that in the present embodiment, the reconstructed spectrum refers to the spectrum data verified by mean square error, which is reconstructed by the PCA basis vector, retains the inherent luminous characteristic of the screen, and is the core input of the target color gamut mapping; the incremental convex hull calculation is an algorithm for real-time updating of the color gamut boundary, the CIE xy chromaticity coordinates of the reconstructed spectrum are extracted pixel by pixel, which are converted from the XYZ tristimulus values calculated by the trapezoidal integral method (x=X / (X+Y+Z), y=Y / (X+Y+Z), z=Z / (X+Y+Z)), and the minimum convex polygon of these coordinates, i.e. the actual color gamut boundary, is dynamically maintained by the Graham scan method, which greatly reduces the computational complexity compared with the traditional batch convex hull calculation (recomputation of each frame), is more suitable for real-time scenarios with a refresh rate of 120Hz+, and can accurately reflect the current actual display capability of the screen; the pre-stored target color gamut boundary is the boundary of the target color gamut (such as DCI-P3, sRGB) set offline, which can be stored in the BRAM of the FPGA in the form of vertex list for comparison of the region to which the pixel belongs; the super color gamut region refers to the region where the chromaticity coordinates of the reconstructed spectrum exceed the target color gamut boundary, which needs to be compressed to the target boundary to avoid color deviation; the uncovered region refers to the region where the chromaticity coordinates of the reconstructed spectrum are within the target color gamut boundary but the screen cannot display, for example, color gamut contraction caused by insufficient sub-pixel brightness, which retains information through color gamut expansion technology or alternative color selection; the region mapping strategy is a personalized processing method for different regions, the super color gamut region can use absolute mapping, compressing the saturation along the constant hue line to maintain the hue unchanged, the uncovered region uses color gamut expansion technology, linear interpolation to the target boundary or alternative color selection, using the closest color within the target color gamut.

[0108] The technical scheme of the present embodiment realizes the mapping effect of screen characteristic adaptation and strict target color gamut fitting by real-time calculation of the actual color gamut, accurate comparison of the target color gamut, and personalized processing of different regions. The traditional fixed LUT mapping does not consider the actual color gamut of the screen, such as aging and temperature changes, which leads to mapping errors, ensuring that the displayed color meets professional requirements. Among them, the incremental convex hull calculation ensures real-time performance and can dynamically track changes in the screen color gamut; the region mapping strategy is the key to accuracy, different methods are adopted for super color gamut and uncovered regions to avoid information loss or color deviation caused by one-size-fits-all mapping.

[0109] In a possible implementation, the incremental convex hull calculation reconstructs the xy coordinates of the spectrum pixel by pixel, and a Graham scan method is used to maintain a convex hull vertex list, such as storing up to 8 vertices, and the actual gamut boundary is updated once per frame; the pre-stored target gamut boundary (such as DCI-P3) is stored in a BRAM, and is an xy coordinate of 8 vertices; the boundary comparison can use a ray method, such as a point-in-polygon algorithm, to determine whether the xy coordinate is within the target gamut, such as determining whether the number of times that a ray extends rightward from the point and passes through the boundary is odd; and the region mapping strategy can use a 3D LUT storage, an absolute mapping LUT of the super gamut region stores the xy coordinates compressed along a constant hue line, an extension LUT of the uncovered region stores the xy coordinates linearly interpolated, and the corresponding LUT is queried according to the region during real-time processing.

[0110] Further, determining the region mapping strategy based on the region to which the pixel belongs includes:

[0111] If the region to which the pixel belongs is a super gamut region, absolute gamut mapping is adopted, and a region mapping strategy of compressing saturation along a constant hue line to a target gamut boundary is adopted.

[0112] If the region to which the pixel belongs is an uncovered region, a gamut extension or a region mapping strategy of alternative color selection is adopted.

[0113] It should be noted that in the present embodiment, the super gamut region refers to a region in which the chromaticity coordinates (converted from XYZ three stimulus values calculated by the trapezoidal integral method) of the reconstructed spectrum exceed the pre-stored target gamut boundary, for example, the maximum value of x of the DCI-P3 target gamut is 0.64, and if x of the reconstructed spectrum is 0.65, the region belongs to the super gamut region, that is, the color displayed on the screen exceeds the range of the target gamut, resulting in over-saturation and color deviation, such as displaying red as “eye-catching magenta”. The absolute gamut mapping is a priority processing strategy for the super gamut region, which refers to maintaining the hue unchanged, that is, compressing the saturation along a constant hue line to the target gamut boundary, so that the color conforms to the specification of the target gamut without changing the “color category” perceived by the user, such as keeping red as red, to avoid user misunderstanding caused by hue change, such as changing red to orange. The constant hue line refers to a straight line determined by the hue angle of the chromaticity coordinates of the pixel, and the hue angle is a core attribute of the color, for example, the hue angle of red is about 20°-40°, and the hue angle of blue is about 200°-240°, and maintaining the hue unchanged ensures that the user's basic cognition of the color is consistent. Saturation refers to the brightness of the color, and compressing the saturation means reducing the saturation value to the maximum saturation value of the target gamut boundary, to ensure that the color is within the target gamut.

[0114] The uncovered area refers to an area in which the chromaticity coordinates of the reconstructed spectrum are within the boundary of the target color gamut but cannot be displayed on the screen, for example, due to insufficient sub-pixel brightness or Gamma curve offset, resulting in color gamut contraction. If the minimum value of x of the target color gamut is 0.3127, and the x of the reconstructed spectrum is 0.30, the area belongs to the uncovered area, that is, the screen cannot restore all colors of the target color gamut. The color gamut expansion is a priority strategy for the uncovered area, which refers to extending the chromaticity coordinates of the uncovered area to the boundary of the target color gamut through linear interpolation, with the purpose of preserving the relative relationship of colors, for example, the gradient change of the dark part, to avoid information loss. The substitute color selection can be used as a backup strategy when the color gamut expansion cannot be implemented. When the screen brightness is limited, the substitute color selection is used to select the color closest to the color of the uncovered area in the target color gamut, to preserve the main information of the color as much as possible.

[0115] The embodiment prioritizes user perception and region individualization. When the system determines the region to which the pixel belongs (super color gamut or uncovered) through boundary comparison, the corresponding strategy is selected for different regions. For the super color gamut region, the hue is preferentially kept unchanged to avoid color category change, and the saturation is compressed to the target boundary. For the uncovered region, the color gamut expansion is preferentially attempted to preserve details, and the substitute color is selected if the expansion cannot be implemented to preserve the main information. The embodiment realizes the balance between specification requirements and user experience, ensuring that the displayed color meets the target color gamut, and avoiding "color misunderstanding" (such as red turning into orange) or "information loss" (such as dark details being invisible) caused by mapping.

[0116] Further, with reference to Figure 4 , the fourth embodiment of the image display method of the present application provides a flowchart. Based on the above Figure 4 embodiment, the step S50 "correcting the mapping spectrum based on the ambient spectrum to obtain a corrected target spectrum, and converting the corrected target spectrum into a driving signal" is further refined, and further includes steps A601-A605:

[0117] Step A601, calculating the ambient reflected spectrum based on the ambient spectrum and the pre-stored screen reflectivity;

[0118] It should be noted that the ambient spectrum refers to the spectral power distribution (SPD) of the ambient light collected synchronously with the screen spectrum data, covering the visible light band of 400-700 nm, and the collection position simulates the user's viewing angle, which is used to quantify the interference of the ambient light on the human eye perception. The pre-stored screen reflectivity refers to the off-line screen surface diffuse reflectivity p measured by an integrating sphere, which is usually 0.1-0.2, and is stored in the BRAM of the FPGA, reflecting the proportion of the ambient light reflected by the screen. The ambient reflected spectrum refers to the spectrum of the ambient light reflected by the screen into the human eye, and the formula is L R (λ)=ρ×L a (λ) (L a(L) is the ambient reflection spectrum, which aims to quantify the impact of ambient reflection on human eye perception of color, for example, yellowish ambient light will cause the reflected spectrum to have a peak at 580nm, making the human eye perceive the screen white to be yellowish.

[0119] Step A602, based on the ambient reflection spectrum and the mapping spectrum, obtain the corrected target spectrum;

[0120] It should be noted that the corrected target spectrum refers to the spectrum that the display screen needs to actually emit, and the formula is

[0121] L C (L) = L M (L) - L R (L) (L M (L) is the mapping spectrum, that is, the spectrum perceived by the human eye = screen emission spectrum + ambient reflection spectrum, by making the screen emission spectrum equal to "mapping spectrum - ambient reflection spectrum", the spectrum perceived by the human eye is exactly equal to the mapping spectrum (color required by the target color gamut), thereby offsetting the color deviation of the ambient reflection, for example, when the ambient light is yellowish, the corrected target spectrum will increase the blue component to offset the reflected yellow color.

[0122] Step A603, check whether the corrected target spectrum is within the target color gamut boundary, and adjust the corrected target spectrum based on the region processing strategy;

[0123] It should be noted that the corrected target spectrum is used to ensure that the subtraction of the ambient reflection spectrum may cause the corrected target spectrum to exceed or be insufficient, so as to meet the requirements of the target color gamut, and the system adjusts the corrected target spectrum through the region processing strategy to ensure that the chromaticity coordinates are within the target color gamut boundary.

[0124] Step A604, discretization processing is performed on the corrected target spectrum that passes the check, and XYZ tristimulus values are calculated by trapezoidal integration method;

[0125] It should be noted that discretization processing refers to converting the corrected target spectrum from continuous signal to discrete data of 16 wavebands, which aims to adapt to the calculation requirements of the trapezoidal integration method; the trapezoidal integration method is a classical method for calculating XYZ tristimulus values, which converts spectral data into color space data (XYZ) and connects the spectrum and the driving signal.

[0126] Step A605, based on the XYZ tristimulus values, real-time query the pre-stored color gamut mapping lookup table LUT, and output the corresponding driving signal.

[0127] It should be noted that the pre-stored color gamut mapping lookup table (LUT) is an offline generated 3D lookup table, for example, a 17x17x17 grid covering the XYZ range of the target color gamut, the input is the XYZ tristimulus value of the modified target spectrum, and the output is the driving signal of the screen sub-pixel, and the generation process needs to combine the inherent characteristics of the screen, such as sub-pixel SPD, Gamma curve, maximum brightness, to ensure the linear relationship between the driving signal and the display color; real-time query refers to storing the LUT in the BRAM of the FPGA, and processing the case where the XYZ value is not on the grid point through three linear interpolation, and outputting the driving signal to ensure that the delay meets the requirements.

[0128] The technical solutions of environmental reflection offset, color gamut compliance verification, color space conversion, and driving signal output in the embodiment solve the problem of display color deviation caused by environmental light reflection, and ensure that the display color still meets the target color gamut requirements in a dynamic environment, such as daytime / nighttime switching of a vehicle-mounted display. Each step can be realized through FPGA hardware acceleration to ensure real-time performance and accuracy.

[0129] In a possible implementation, the manufacturer needs to solve the screen characteristic differences of batch production of spliced screens and the personalized needs of users, and improve batch consistency and user satisfaction through local real-time processing combined with distributed batch LUT generation and personalized strategy optimization in the cloud. Among them, the screen spectrum and the environmental spectrum are synchronously collected on the local device, and spectrum compression and reconstruction, target color gamut mapping, environmental correction, and driving signal generation are performed; in the cloud, the reconstructed spectrum data of the spliced screen uploaded locally is collected, a general color gamut mapping LUT is generated through distributed computing, and the cloud receives user feedback, combines the local data of the spliced screen, and optimizes the regional processing strategy of the spliced screen through Python offline to realize personalized strategy optimization; the spliced screen is batch corrected through the general color gamut mapping LUT pushed by the cloud, and the personalized regional processing strategy pushed and optimized is fed back to meet the personalized needs of users. The embodiment improves the accuracy, consistency, and user satisfaction of display screen color gamut correction through local real-time processing and cloud offline optimization.

[0130] It should be noted that the above examples are only used to understand the present application and do not constitute a limitation on the display screen color gamut correction method of the present application. More forms of simple transformation based on this technical concept are within the protection scope of the present application.

[0131] The present application also provides a display screen color gamut correction device, which is described with reference to Figure 5 The display screen color gamut correction device comprises:

[0132] 10, a spectrum acquisition module, configured to acquire screen spectrum data based on a multispectral camera and synchronously acquire environmental spectrum;

[0133] 20 a spectrum compression module, configured to process the screen spectrum data in real time by spectrum compression coding to output compressed spectrum data;

[0134] 30 a spectrum reconstruction module, configured to reconstruct a spectrum feature based on the compressed spectrum data to obtain a reconstructed spectrum;

[0135] 40 a target color gamut mapping module, configured to perform target color gamut mapping processing on the reconstructed spectrum to output a mapped spectrum;

[0136] 50 a signal processing module, configured to correct the mapped spectrum based on the ambient spectrum to obtain a corrected target spectrum, and convert the corrected target spectrum into a driving signal.

[0137] The display screen color gamut correction device provided in the present application adopts the display screen color gamut correction method in the above embodiments, and can solve the technical problem that high-precision and real-time color gamut control and display color accuracy cannot be achieved in a dynamic environment. Compared with the prior art, the display screen color gamut correction device provided in the present application has the same beneficial effects as the display screen color gamut correction method provided in the above embodiments, and other technical features in the display screen color gamut correction device are the same as the features disclosed in the above embodiments, which will not be described here.

[0138] The present application provides a display screen color gamut correction device, which comprises at least one processor and a memory in communication connection with the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to execute the display screen color gamut correction method in Embodiment I.

[0139] Reference will be made to the following description Figure 6 which shows a structural schematic diagram of a display screen color gamut correction device suitable for implementing the embodiments of the present application. The display screen color gamut correction device in the embodiments of the present application can include but is not limited to mobile terminals such as mobile phones, notebook computers, digital broadcast receivers, PDAs (Personal Digital Assistant), PADs (Portable Application Description), PMPs (Portable Media Player), vehicle-mounted terminals (such as vehicle-mounted navigation terminals), and the like, and fixed terminals such as digital TVs, desktop computers, and the like. Figure 6 The display screen color gamut correction device shown is only an example, and should not impose any limitation on the functions and use range of the embodiments of the present application.

[0140] As Figure 6As shown, the display color gamut proofing device can include a processing device 1001 (e.g., a central processing unit, a graphics processing unit, etc.) that can perform various appropriate actions and processes according to programs stored in a read-only memory 1002 or loaded from a storage device 1003 into a random access memory 1004. Various programs and data required for the operation of the display color gamut proofing device are also stored in the random access memory 1004. The processing device 1001, the read-only memory 1002, and the random access memory 1004 are connected to each other through a bus 1005. An input / output interface 1006 is also connected to the bus. Generally, the following systems can be connected to the input / output interface 1006: input devices 1007 including, for example, a touch screen, a touch pad, a keyboard, a mouse, an image sensor, a microphone, an accelerometer, a gyroscope, etc.; output devices 1008 including, for example, a liquid crystal display (LCD), a speaker, a vibrator, etc.; the storage device 1003 including, for example, a magnetic tape, a hard disk, etc.; and a communication device 1009. The communication device 1009 can allow the display color gamut proofing device to communicate with other devices wirelessly or by wire to exchange data. Although the display color gamut proofing device with various systems is shown in the figure, it should be understood that all the systems shown are not required to be implemented or possessed. More or fewer systems can be alternatively implemented or possessed.

[0141] In particular, according to the embodiments disclosed in the present application, the processes described above with reference to the flowcharts can be implemented as a computer software program. For example, the embodiments disclosed in the present application include a computer program product comprising a computer program carried on a computer readable medium, the computer program containing program codes for executing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network through the communication device, or installed from the storage device 1003, or installed from the read-only memory 1002. When the computer program is executed by the processing device 1001, the above-mentioned functions defined in the methods of the embodiments disclosed in the present application are performed.

[0142] The display color gamut proofing device provided by the present application adopts the display color gamut proofing method in the above-mentioned embodiments, and can solve the technical problem that high-precision and real-time color gamut control and display color accuracy cannot be achieved in a dynamic environment. Compared with the prior art, the display color gamut proofing device provided by the present application has the same beneficial effects as the display color gamut proofing method provided by the above-mentioned embodiments, and other technical features in the display color gamut proofing device are the same as the features disclosed in the previous embodiment method, which will not be described here.

[0143] It should be understood that various parts of the present application can be realized with hardware, software, firmware or a combination thereof. In the above description of embodiments, specific functional configurations, structures, materials or characteristics can be combined in any appropriate manner in one or more embodiments or examples.

[0144] The above description is merely a specific implementation of the present application, but the scope of protection of the present application is not limited thereto. Any person skilled in the art can easily think of changes or replacements within the technical scope disclosed by the present application, and all such changes or replacements should be covered within the scope of protection of the present application. Therefore, the scope of protection of the present application should be subject to the scope of protection of the claims.

[0145] The present application provides a computer readable storage medium having stored thereon computer readable program instructions (i.e. computer programs) for performing the display screen gamut proofing method in the above embodiments.

[0146] The computer readable storage medium provided by the present application may, for example, be a U disk, but is not limited to an electric, magnetic, optical, electromagnetic, infrared, or semiconductor system or device, or any combination thereof. More specific examples of the computer readable storage medium can include, but are not limited to, an electric connection with one or more conductive wires, a portable computer disk, a hard disk, a random access memory (RAM), a read only memory (ROM), an erasable programmable read only memory (EPROM or flash memory), an optical fiber, a portable compact disk read only memory (CD-ROM), an optical storage device, a magnetic storage device, or any appropriate combination thereof. In the present embodiment, the computer readable storage medium can be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system or device. The program code contained on the computer readable storage medium can be transmitted by any appropriate medium, including but not limited to an electric wire, an optical cable, an RF (Radio Frequency), etc., or any appropriate combination thereof.

[0147] The above computer readable storage medium can be contained in the display screen gamut proofing device; or can exist separately without being assembled into the display screen gamut proofing device.

[0148] The computer readable storage medium carries one or more programs, when the one or more programs are executed by the display screen color gamut calibration device, the display screen color gamut calibration device is caused to: acquire screen spectrum data based on a multispectral camera, and synchronously acquire ambient spectrum; process the screen spectrum data in real time through spectral compression coding, and output compressed spectrum data; perform spectral feature reconstruction based on the compressed spectrum data, and obtain reconstructed spectrum; perform target color gamut mapping processing on the reconstructed spectrum, and output mapped spectrum; correct the mapped spectrum based on the ambient spectrum to obtain corrected target spectrum, and convert the corrected target spectrum into a driving signal.

[0149] Computer program code for carrying out operations of the present application can be written in any combination of one or more programming languages, including an object oriented programming language such as Java, Smalltalk, C++ or the like and conventional procedural programming languages, such as the "C" programming language or similar programming languages. The program code can execute entirely on the user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer and partly on a remote computer or entirely on the remote computer or server. In the latter scenario, the remote computer can be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or the connection can be made to an external computer (for example, through the Internet using an Internet Service Provider).

[0150] The computer program instructions can also be loaded onto a computer or other programmable information processing apparatus to cause a series of operations to be performed on the computer or other programmable information processing apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable information processing apparatus implement the functions / acts specified in the flowchart and / or block diagram block or blocks.

[0151] The modules described in the embodiments of the present application can be implemented in the form of software or in the form of hardware. In some cases, the names of the modules do not constitute a limitation on the modules themselves.

[0152] The readable storage medium provided by the present application is a computer readable storage medium, which stores computer readable program instructions (i.e., a computer program) for executing the display screen color gamut calibration method described above, and can solve the technical problem that high-precision and real-time color gamut control and display color accuracy cannot be achieved in a dynamic environment. Compared with the prior art, the computer readable storage medium provided by the present application has the same beneficial effects as the display screen color gamut calibration method provided by the above embodiments, and will not be described here.

[0153] The present application also provides a computer program product, comprising a computer program, which, when executed by a processor, implements the steps of the display screen color gamut calibration method as described above.

[0154] The computer program product provided by the present application can solve the technical problem that high-precision and real-time color gamut control and display color accuracy cannot be achieved in a dynamic environment. Compared with the prior art, the computer program product provided by the present application has the same beneficial effects as the display screen color gamut calibration method provided by the above embodiments, and will not be described here.

[0155] The above only describes some embodiments of the present application, and does not limit the patent scope of the present application. Any equivalent structural transformation, direct / indirect application in other related technical fields based on the technical concept of the present application, and the content of the specification and drawings are included in the patent protection scope of the present application.

Claims

1. A method for color gamut calibration of a display screen, characterized in that, The display screen color gamut calibration method includes: Screen spectral data is acquired using a multispectral camera, and environmental spectra are acquired simultaneously. The screen spectral data is processed in real time by spectral compression encoding, and compressed spectral data is output. Based on the compressed spectral data, spectral features are reconstructed to obtain the reconstructed spectrum; The reconstructed spectrum is subjected to target color gamut mapping processing to output the mapped spectrum; The modified target spectrum is obtained by correcting the mapped spectrum based on the environmental spectrum, and the modified target spectrum is converted into a driving signal; The steps of acquiring screen spectral data based on a multispectral camera and simultaneously acquiring environmental spectra include: Send a color block display command to the display screen to make the display screen display a standard color target; The screen spectral data of the display under a standard color target is acquired using a multispectral camera, and the timestamp is obtained. Based on the timestamp, the ambient light sensor is synchronously triggered to collect the ambient spectrum; The step of correcting the mapped spectrum based on the environmental spectrum to obtain the corrected target spectrum and converting the corrected target spectrum into a driving signal includes: The ambient reflectance spectrum is calculated based on the ambient spectrum and the pre-stored screen reflectance. Based on the environmental reflectance spectrum and the mapped spectrum, the corrected target spectrum is obtained; Verify whether the corrected target spectrum is within the target color gamut boundary, and adjust the corrected target spectrum based on the region processing strategy; The corrected target spectrum that has passed the verification is discretized, and the XYZ tristimulus values ​​are calculated using the trapezoidal integral method. Based on the XYZ tristimulus values, the pre-stored gamut mapping lookup table (LUT) is queried in real time, and the corresponding driving signal is output.

2. The display screen color gamut calibration method as described in claim 1, characterized in that, The step of processing the screen spectral data in real time through spectral compression encoding and outputting compressed spectral data includes: The screen spectral data is preprocessed; The preprocessed screen spectral data was dimensionality reduced using principal component analysis algorithm. The dimensionality-reduced screen spectral data is processed using an adaptive quantization method to obtain quantized data; The quantized data is encoded to output compressed spectral data.

3. The display screen color gamut calibration method as described in claim 2, characterized in that, The step of reconstructing spectral features based on the compressed spectral data to obtain the reconstructed spectrum includes: The compressed spectral data is decoded and dequantized to obtain dequantized data; Based on the inverse quantization data and the pre-stored basis vector matrix, the reconstructed spectrum is obtained through a spectral reconstruction model; Calculate the mean square error between the reconstructed spectrum and the original spectrum; If the mean square error is less than a first preset threshold, the reconstructed spectrum is output.

4. The display screen color gamut calibration method as described in claim 3, characterized in that, The step of performing target color gamut mapping processing on the reconstructed spectrum and outputting the mapped spectrum includes: The actual color gamut boundary is obtained by incremental convex hull calculation based on the reconstructed spectrum. The actual color gamut boundary is compared with the pre-stored target color gamut boundary to determine the region to which the pixel belongs. The region to which the pixel belongs includes the super-color gamut region and the uncovered region. A region mapping strategy is determined based on the region to which the pixel belongs, and a mapping spectrum is obtained through the corresponding region mapping strategy.

5. The display screen color gamut calibration method as described in claim 4, characterized in that, The region mapping strategy based on the region to which the pixel belongs includes: If the region to which the pixel belongs is a super-gamut region, then an absolute gamut mapping strategy is adopted, which is a region mapping strategy that compresses saturation along a constant hue line to the boundary of the target gamut. If the region to which the pixel belongs is an uncovered region, then a region mapping strategy that either expands the color gamut or replaces color selection is adopted.

6. A display screen color gamut calibration device, characterized in that, The display screen color gamut calibration device includes: The spectral acquisition module is used to acquire screen spectral data based on a multispectral camera and simultaneously acquire ambient spectrum; it is also used to send color block display instructions to the display screen to display a standard color target; it acquires screen spectral data of the display screen under the standard color target through the multispectral camera and obtains a timestamp; and it synchronously triggers ambient light sensor acquisition instructions based on the timestamp to acquire ambient spectrum. The spectral compression module is used to process the screen spectral data in real time through spectral compression encoding and output compressed spectral data. The spectral reconstruction module is used to reconstruct spectral features based on the compressed spectral data to obtain the reconstructed spectrum. The target color gamut mapping module is used to perform target color gamut mapping processing on the reconstructed spectrum and output the mapped spectrum; The signal processing module is used to correct the mapped spectrum based on the ambient spectrum to obtain a corrected target spectrum, and convert the corrected target spectrum into a driving signal; it is also used to calculate the ambient reflectance spectrum based on the ambient spectrum and the pre-stored screen reflectance; obtain the corrected target spectrum based on the ambient reflectance spectrum and the mapped spectrum; verify whether the corrected target spectrum is within the target color gamut boundary, and adjust the corrected target spectrum based on a region processing strategy; discretize the corrected target spectrum that passes the verification, and calculate the XYZ tristimulus values ​​using the trapezoidal integral method; query the pre-stored color gamut mapping lookup table (LUT) in real time based on the XYZ tristimulus values, and output the corresponding driving signal.

7. A display screen color gamut calibration device, characterized in that, The device includes: a memory, a processor, and a computer program stored in the memory and executable on the processor, the computer program being configured to implement the steps of the display screen color gamut calibration method as described in any one of claims 1 to 5.

8. A storage medium, characterized in that, The storage medium is a computer-readable storage medium, and a computer program is stored on the storage medium. When the computer program is executed by a processor, it implements the steps of the display screen color gamut calibration method as described in any one of claims 1 to 5.

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