Method for driving four-color film material to display multiple colors through electronic paper three-color chip

Abstract

The invention provides a method for driving a four-color film material to display multiple colors by an electronic paper three-color chip. The method comprises the following steps: converting a color image to be displayed into a 256-gray-scale image and mapping the 256-gray-scale image to a 16-gray-scale image; analyzing 0-F hexadecimal data after 16-gray-scale modulo through an image data algorithm, determining a display change area, and combining pixels of the same driving scheme by adopting a grouping compression algorithm; constructing a gray scale-driving scheme mapping table, and distributing gray scale data to corresponding registers of the three-color chip; performing multi-round layered refreshing; pure display of 5-16 colors is achieved through multiple rounds of refreshing superposition, and only the change area is refreshed. Differentiation driving of the same voltage driving logic on particles of different colors is achieved through multiple driving schemes and particle channels, 5-16 kinds of pure color display are achieved by combining five rounds of layered superposition, color transition is smooth, and pocking marks do not exist in a short distance.

Description

Technical Field

[0001] This invention relates to the field of electronic paper display technology, and in particular to a method for driving a four-color film material to display multiple colors using a three-color chip in electronic paper. Background Technology

[0002] Electronic paper, with its unique advantages such as low power consumption, paper-like visual effect, and flexible display, has been widely used in electronic price tags, e-readers, and smart wearables. Among them, four-color e-ink screens, which can display four basic pure colors (black, white, red, and yellow), have become one of the mainstream products in the market, but they have significant limitations when it comes to multi-color display needs.

[0003] When displaying multi-color images on existing four-color e-ink screens, dithering algorithms are commonly used to simulate target colors by mixing pure pixels of black, white, red, and yellow. This method has several drawbacks: pixelation is prominent during close-up observation, resulting in a rough image; color rendering relies on pixel mixing, making it impossible to achieve pure color transitions and leading to deviations from the true target color; and color customization is poor, making it difficult to meet the color requirements of diverse scenarios. Furthermore, in e-paper display modules, the 1-bit data IC, due to hardware limitations, cannot directly achieve high-quality multi-grayscale and multi-color display. While existing technologies offer solutions to achieve sixteen grayscale levels through multiple refreshes and overlays, these solutions only focus on grayscale enhancement and do not address the need for multi-color display. Moreover, their refresh strategies and waveform control logic lack adaptability to multi-color display and cannot be directly transferred to multi-color extended displays on four-color film materials.

[0004] Therefore, there is an urgent need for a method to drive a four-color film material with a three-color electronic paper chip to display multiple colors. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a method for displaying multiple colors using a three-color chip driven by an electronic paper four-color film. By optimizing grayscale mapping, driving scheme allocation, and multi-round refresh overlay strategy, it achieves the display of 5-16 pure colors and reduces speckle effects.

[0006] The technical solution of the present invention is: a method for driving a four-color film material with a three-color chip in electronic paper to display multiple colors, comprising the following steps: S1) Convert the color image to be displayed into a 256-level grayscale image, and map it to 16 grayscale levels through a uniform quantization algorithm; each target color corresponds to a unique 16-level grayscale value, and the grayscale values ​​of each target color do not overlap; S2) Configure the 1-bit data IC to compare the old and new data modes, analyze the 0-F hexadecimal data after 16 grayscale modulo using image data algorithms, determine the display change area, and use a group compression algorithm to merge pixels with the same driving scheme. S3) Construct a grayscale-driving scheme mapping table and use the k-means clustering algorithm to allocate grayscale data to the corresponding registers of the three-color chip; S4) Perform multiple rounds of layered refresh, with each round controlling 2-4 grayscale data, calling the corresponding driving scheme to drive the movement of the four-color film particles, and adjusting the basic color depth; after each refresh, dynamically adjust the waveform parameters for the next round by acquiring the pixel status; S5) Achieves a pure display of 5-16 colors through multiple rounds of refresh and overlay, and only refreshes the changing areas.

[0007] Preferably, in step S1), the target color includes black, dark red, red, dark yellow, gray 2, orange, yellow, pink, gray 1, and white; the corresponding 16 grayscale values ​​are 0, 3, 5, 6, 8, 9, 10, 11, 12, and 15, respectively.

[0008] Preferably, in step S1), the 1-bit data IC is configured to compare the old and new data, as follows: S211) Configure the register of the 1-bit data IC and write the mode control instruction to switch it to the comparison of old and new data mode. In this mode, the IC's built-in cache unit will store the display data of the previous frame and receive the 0-F hexadecimal data after the 16 grayscale of the current frame in real time. S212) When the difference in grayscale change of a pixel is greater than or equal to the grayscale threshold, it is determined to be a pixel that has changed; when the difference is less than the grayscale threshold, it is determined to be a pixel that has not changed. S213) Enable the IC's change area marking function, and generate a change area mask by comparing the old and new data pixel by pixel through hardware logic circuits.

[0009] Preferably, in step S1), the 0-F hexadecimal data after 16 grayscale modulo is analyzed using an image data algorithm to determine the display change area, as follows: S221) The row and column scanning algorithm is used to traverse the hexadecimal data matrix after 16 gray levels modulo, extract the gray level value of each pixel, and construct the gray level data matrix of the current frame. S222) The neighborhood connectivity analysis algorithm is used to filter isolated single-point changing pixels, and the final changing region data matrix is ​​obtained after filtering.

[0010] Preferably, in step S1), pixels with the same waveform data are merged using a group compression algorithm, as follows: S231) Based on the preset grayscale-driving scheme mapping table, traverse the final change area data matrix and match the corresponding preliminary driving scheme to generate a temporary driving matrix for each changed pixel's grayscale value. S232) The temporary driving matrix is ​​grouped using a region growing clustering algorithm to construct compressed data frames and achieve data compression; S233) Generate a compressed data frame for each group. The data frame format is defined as: {group identifier, area coordinates, waveform type, voltage parameter, check bit}. S234) Calculate the amount of data before and after compression, and calculate the compression ratio.

[0011] Preferably, in step SS232), a region growing clustering algorithm is used to group the temporary driving matrix, construct compressed data frames, and achieve data compression. The specific process is as follows: S2321) Initialize the seed pixel queue, start scanning from the top left corner of the temporary driving matrix, select the first unmarked pixel as the seed pixel, and record its driving scheme; S2322) Taking the seed pixel as the center, traverse its neighboring pixels, determine whether the driving scheme of the neighboring pixels is consistent and whether it is a changing pixel. If so, include it in the current group and mark it as processed. S2323), repeat step S2322), until no new pixels are added to the current group, and output the region coordinates of the current group and the corresponding driving scheme; (S2324) Continue scanning the matrix, select the next unmarked pixel as the new seed pixel, and repeat steps (S2322) - (S2323) until all changed pixels have been grouped.

[0012] Preferably, in step S3), the grayscale-driving scheme mapping table includes grayscale value, target color, color system, corresponding particle, driving scheme type, voltage parameter, particle channel, refresh cycle, and register number.

[0013] Preferably, in step S3), the four-color film material contains four types of charged particles: black, white, red, and yellow. The movement of the particles is controlled by the voltage direction and duration: the positive voltage drives the target particles to migrate towards the display surface, the negative voltage drives the target particles to migrate towards the inside of the film material, and the voltage duration determines the number of particles that migrate, thus presenting different shades of color or mixed colors.

[0014] Preferably, in step S3), the driving scheme type includes four basic driving schemes and multiple hybrid driving schemes, wherein the basic driving scheme drives the movement of a single particle, and the hybrid driving scheme drives the movement of multiple particles. The basic driving schemes include no change, forward drive, reverse drive, and hold-lock; The hybrid driving scheme includes driving combinations corresponding to deep red, pink, deep yellow, orange, gray 1, and gray 2. By combining the basic driving schemes and optimizing the voltage parameters, hybrid driving of different particles can be achieved.

[0015] Preferably, in step S3), the grayscale data is allocated to the corresponding registers of the three-color chip using the k-means clustering algorithm, specifically including the following steps: S31) Extract all non-zero grayscale values ​​from the final changed area data matrix, construct a sample dataset, and define the feature vector for each sample; S32) Based on the number of registers, color system, and refresh cycle distribution of the three-color chip, set the number of clusters. ; S33) The elbow rule is used to determine the initial cluster centers, selecting those with the largest differences in feature vectors. One sample was used as the initial center; S34) Calculate the Euclidean distance between each sample and each cluster center; assign each sample to the cluster corresponding to the cluster center with the closest Euclidean distance, take the mean of the feature vectors of all samples in the cluster, and update the cluster center; Repeat the Euclidean distance calculation, sample allocation, and center update steps until the change in cluster centers meets the convergence condition, then stop the iteration. (S35) The converged clusters are allocated to the main register of the three-color chip according to the priority of color system, particle channel and refresh round. The spare register is used to cache temporary data and feedback adjustment parameters during the refresh process.

[0016] Preferably, in step S4), based on the register allocation result and the drive control of the 1-bit data IC, a 5-round layered refresh process is designed. Each round of refresh calls the corresponding drive scheme stored in the register, and the color display is achieved by driving the particle movement through voltage. After refresh, the pixel status is collected through the feedback module, and the waveform parameters of the next round are dynamically adjusted.

[0017] Preferably, in step S4), the same forward driving voltage can be bound to any one of the particle channels: white, red, yellow, or black. The binding relationship can be switched by register instructions to achieve differentiated driving of particles of different colors by the same voltage driving logic. In the first round of forward driving, the white channel is bound to drive white particles, and in the second round of forward driving, the red channel is bound to drive red particles.

[0018] Preferably, in step S4), after each refresh, the actual grayscale value and actual optical brightness of the pixel are collected by the feedback module and compared with the target value to calculate the deviation value. If the deviation value exceeds the preset threshold, the voltage duration of the corresponding driving scheme in the next round is adjusted according to the rules.

[0019] The beneficial effects of this invention are as follows: 1. This invention achieves differentiated driving of different colored particles by the same voltage driving logic through multiple driving schemes and particle channels. Combined with 5 rounds of layered superposition, it can achieve 5-16 pure color display with smooth color transition, no speckles at close range, and the total refresh time is controlled within 27-30 seconds. 2. After each refresh, the present invention dynamically collects status data through a feedback module and adjusts the driving scheme parameters based on the deviation ratio. The color drift is ≤0.2 gray levels and the brightness deviation is ≤8 cd / m². 3. This invention can add colors by updating the driving scheme, particle channel combination, and clustering parameters in the grayscale-driving scheme mapping table; reserved registers and extended clusters can adapt to future scenarios with higher color requirements. Attached Figure Description

[0020] Figure 1 This is a schematic flowchart of the method of the present invention; Figure 2 This is a flowchart illustrating the image data algorithm of the present invention; Figure 3 This is a flowchart illustrating the group compression algorithm of the present invention; Figure 4 This is a flowchart illustrating the k-means clustering algorithm of the present invention; Figure 5 This is a comparison diagram of the multicolor display effects of the present invention and existing technologies. Detailed Implementation

[0021] The specific embodiments of the present invention will be further described below with reference to the accompanying drawings: like Figure 1 As shown, this embodiment provides a method for driving a four-color film material with a three-color chip in electronic paper to display multiple colors, including the following steps: S1) Convert the color image to be displayed into a 256-grayscale image, and map the 256-grayscale image to 16 grayscale using a uniform quantization algorithm; each target color corresponds to a unique 16-grayscale value, and the grayscale values ​​of each target color do not overlap. In this embodiment, the uniform quantization algorithm is expressed as: ,

[0022] In the formula, This represents the quantized 16 grayscale values; Grayscale values ​​ranging from 0 to 256; This represents the floor function; Select the target display color and ensure that the grayscale values ​​of each target color do not overlap and are significantly different after the RGB parameters are converted to 16 grayscale levels to avoid color confusion.

[0023] For example, this embodiment provides the target color and parameters as shown in Table 1; Table 1 Target Colors and Parameters

[0024] S2) Configure the 1-bit data IC to compare the old and new data modes, analyze the 0-F hexadecimal data after 16 grayscale modulo using image data algorithms, determine the display change area, and use a group compression algorithm to merge pixels with the same waveform data. In this embodiment, the 1-bit data IC is configured to compare the old and new data modes, as follows: S211) Configure the register of the 1-bit data IC and write the mode control instruction to switch it to the comparison of old and new data mode. In this mode, the IC's built-in cache unit will store the display data of the previous frame and receive the 0-F hexadecimal data after the 16 grayscale of the current frame in real time. S212), and in this embodiment, a pixel grayscale change difference ≥ 1 is determined as a changed pixel, and a difference < 1 is determined as an unchanged pixel, so as to avoid invalid refresh caused by slight grayscale fluctuations; S213) Enable the IC's change area marking function. The hardware logic circuit compares the new and old data pixel by pixel to generate a change area mask. In the mask, 1 represents a changed pixel and 0 represents an unchanged pixel. The mask data corresponds one-to-one with the display pixel array.

[0025] In this embodiment, as Figure 2 As shown, the 0-F hexadecimal data after 16 grayscale levels are analyzed using image data algorithms to determine the display variation area, as detailed below: S221) The row and column scanning algorithm is used to traverse the hexadecimal data matrix after 16 gray levels modulo extraction to extract the gray level value of each pixel. Construct the grayscale data matrix of the current frame. ,in, The number of rows and columns of the hexadecimal data matrix; S222) A neighborhood connectivity analysis algorithm is used to filter isolated single-point changed pixels. The single-point changed pixels are pixels with a connected region area of ​​less than 3 pixels. These pixels are usually noise interference. After filtering, the final changed region data matrix is ​​obtained. .

[0026] In this embodiment, as Figure 3 As shown, pixels with the same waveform data are merged using a group compression algorithm, as detailed below: S231) Based on the preset grayscale-driving scheme mapping table, traverse the final change area data matrix. grayscale value for each changing pixel Generate a temporary driving matrix by matching the corresponding preliminary driving scheme. ; S232) The region growing clustering algorithm is used to process the temporary driving matrix. The data is grouped, compressed into frames, and compressed to achieve data compression. The specific process is as follows: S2321) Initialize the seed pixel queue from the temporary driving matrix. The scanning begins from the top left corner, selecting the first unmarked pixel as the seed pixel and recording its driving scheme. ; (S2322) Taking the seed pixel as the center, traverse its 8 neighboring pixels and determine whether the driving scheme of the neighboring pixels is consistent with... If the pixel is consistent and is a changed pixel, then include it in the current group and mark it as processed; (S2323) Repeat step S2322) until no new pixels are added to the current group, then output the region coordinates of the current group and the corresponding driving scheme. ; (S2324) Continue scanning the matrix, select the next unmarked pixel as the new seed pixel, and repeat steps (S2322) - (S2323) until all changed pixels have been grouped.

[0027] S233) Generate a compressed data frame for each group. The data frame format is defined as: {group identifier, area coordinates, waveform type, voltage parameter, check bit}.

[0028] S234) Calculate the data volume before and after compression, and calculate the compression ratio. : ,

[0029] in, , The amount of data before and after compression; ensure a compression ratio of ≥30% to meet the data transmission requirements of high-resolution modules.

[0030] S3) Construct a grayscale-driving scheme mapping table and use the k-means clustering algorithm to allocate grayscale data to the corresponding registers of the three-color chip; In this embodiment, the four-color film material contains four types of charged particles: black, white, red, and yellow. The movement of the particles is controlled by the voltage direction and duration: a positive voltage drives the target particles to migrate toward the display surface, a negative voltage drives the target particles to migrate toward the inside of the film material, and the voltage duration determines the number of particles that migrate, thus presenting different shades of color or mixed colors.

[0031] Four basic driving schemes and multiple hybrid driving schemes are set up, wherein the basic driving schemes drive the movement of a single particle, and the hybrid driving schemes drive the movement of multiple particles.

[0032] In this embodiment, by clustering the 16 grayscale data according to color system and refresh cycle, and distributing it to two independent registers of the three-color chip, efficient utilization of register resources is achieved, and data conflicts are avoided. Figure 4 As shown, the specific steps include the following: S31), from the final changed region data matrix Extract all non-zero grayscale values ​​and construct the sample dataset. ; ; In the formula, This represents the total number of pixels that changed. Feature vector of each sample Defined as: ,

[0033] In the formula, The grayscale value of a pixel; Color system encoding; Encoding the particle channels; To refresh the round code; S32) Based on the number of registers, color system, and refresh cycle distribution of the three-color chip, set the number of clusters. (Two registers are reserved as spare buffers) to ensure that the data streams corresponding to each cluster do not conflict and can be processed in parallel in the same round of refresh; S33) The elbow rule is used to determine the initial cluster centers, selecting those with the largest differences in feature vectors. One sample was used as the initial center. ; (Black theme, black and white channels, round 1) (Red theme, red and white channels, round 2); (Red series, red and black channels, round 3); (Yellow color scheme, yellow and black channels, round 4); (Yellow color scheme, red and yellow channels, round 3); (White theme, white passage, round 1); S34) Calculate each sample With each cluster center Euclidean distance ,Right now: ,

[0034] In the formula, For the first The grayscale value of each pixel; For the first Color system encoding of each pixel; For the first Refresh cycle encoding of each pixel; For the first Particle channel encoding of 1 pixel; Then each sample is assigned to the cluster corresponding to the nearest cluster center. The cluster centers are updated by taking the mean of the feature vectors of all samples within the cluster. ; Repeat the above steps of distance calculation, sample allocation, and center update until the change in cluster centers is ≤0.1, then stop the iteration.

[0035] (S35) The six converged clusters are allocated to the two main registers of the three-color chip according to the priority of color system, particle channel and refresh round. The spare register is used to cache temporary data and feedback adjustment parameters during the refresh process.

[0036] S4) Perform multiple rounds of layered refresh, with each round controlling 2-4 grayscale data. Call the basic driving scheme or hybrid driving scheme in the corresponding register to drive the movement of the four-color film particles and adjust the basic color depth. After each refresh, dynamically adjust the waveform parameters of the next round through the pixel status. In this embodiment, based on the register allocation result and the drive control of the 1-bit data IC, a 5-round layered refresh process is designed. Each round of refresh calls the corresponding drive scheme stored in the register, and color display is achieved by driving particle movement through voltage. After refresh, the pixel status is collected through the feedback module, and the waveform parameters for the next round are dynamically adjusted to form a closed-loop control. The specific steps are as follows: In this embodiment, the sampling frequency of the feedback module is 100Hz, the sampling precision is 12 bits, and the sampling area covers all effective pixels of the display module. Set pixel status evaluation metrics: including actual grayscale values Actual optical brightness ; Preset actual grayscale value With target grayscale value The deviation is ≤0.2, and the actual optical brightness is... With target brightness The deviation is ≤8cd / m²; Define parameter adjustment rules: If the deviation exceeds the threshold, dynamically adjust the voltage duration of the corresponding waveform in the next round by multiplying the deviation ratio by the adjustment step size. The adjustment step size is 0.5ms, and the voltage amplitude is fixed at ±15V or a preset value to avoid particle motion instability caused by amplitude adjustment.

[0037] First refresh: Basic display of solid black, red, and yellow colors; The driver chip sends a data read instruction to the main register to extract the compressed driver scheme and voltage parameters, and at the same time activates the corresponding particle channel; The 1-bit data IC calls and executes the basic driver and hybrid driver, driving the four-color film particles to move according to preset voltage parameters, as follows: Black display: Black particles in the black channel are driven by a positive voltage, causing them to migrate completely to the display surface and appear pure black.

[0038] Red display: Red particles in the red channel are driven by a positive voltage, causing them to migrate completely to the display surface and appear pure red.

[0039] Yellow display: By driving the yellow particles in the yellow channel with a positive voltage, the yellow particles are completely migrated to the display surface, presenting a pure yellow color.

[0040] After the refresh is complete, the feedback module collects data for each sampling point and records the actual grayscale value. Actual optical brightness Calculate the deviation value. If it does not exceed the threshold, no parameter adjustment is needed. If the deviation exceeds the threshold, adjust the next round according to the rules and store the actual state data refreshed in this round in the spare register. Second refresh: Displaying red and yellow colors; The driver chip reads the driver scheme from the main register, while the backup register retrieves the baseline state data refreshed in the first round. Implement basic driver and hybrid driver schemes: Deep red display: By driving the black particles in the red channel with a positive voltage, they are completely migrated to the display surface, resulting in a deep red color; Pink display: Through a hybrid driving scheme, a small number of red particles in the red channel are first driven to migrate with a positive voltage, and then a large number of white particles in the white channel are driven to migrate with a positive voltage. The two types of particles mix on the display surface to form pink. The actual grayscale values ​​of deep red and pink are collected through the feedback module. Actual optical brightness The deviation value is calculated. If it does not exceed the threshold, no parameter adjustment is required. If the deviation exceeds the threshold, the next round is adjusted according to the rules, and the actual state data of the deep red and pink refreshed in this round is updated to the spare register.

[0041] Third refresh: Displaying red and yellow colors; The driver chip reads the driver scheme from the main register, retrieves the yellow-tone reference state data from the spare register, and simultaneously reads the adjustment parameters from the spare register. Deep yellow display: Through hybrid drive, the red particles in the red channel are first driven to migrate completely with a positive voltage, and then a small number of black particles in the black channel are driven to approach the red particles with a reverse voltage. The two types of particles mix to form deep red.

[0042] Orange display: Through hybrid drive, the red particles in the red channel are partially driven to migrate with a positive voltage, while the yellow particles in the yellow channel are partially driven to migrate with a positive voltage. The two types of particles are mixed according to the voltage ratio, resulting in an orange color.

[0043] The actual grayscale values ​​of deep yellow and orange are collected through the feedback module. Actual optical brightness The deviation value is calculated. If it does not exceed the threshold, no parameter adjustment is required. If the deviation exceeds the threshold, the next round is adjusted according to the rules, and the actual status data of dark red and orange refreshed in this round is updated to the spare register.

[0044] Fourth refresh: Gray and white color scheme displayed; The driver chip reads the driver scheme from the main register and retrieves the reference state data from the spare register to adjust the parameters.

[0045] Gray 1 display: Through hybrid driving, a large number of black particles in the black channel are first driven to migrate with a positive voltage, and then a small number of white particles in the white channel are driven to migrate with a negative voltage. The two types of particles are mixed on the display surface to present dark gray.

[0046] The actual grayscale values ​​of yellow and dark yellow are collected through the feedback module. Actual optical brightness The deviation value is calculated. If it does not exceed the threshold, no parameter adjustment is required. If the deviation exceeds the threshold, the next round is adjusted according to the rules, and the actual status data of yellow and dark yellow refreshed in this round is updated to the spare register.

[0047] Fifth refresh: Gray and white color scheme displayed; The driver chip reads the driver scheme from the main register and retrieves the reference state data from the spare register to adjust the parameters.

[0048] Gray 2 display: Through hybrid driving, a large number of black particles in the black channel are first driven to migrate with a positive voltage, and then a small number of white particles in the white channel are driven to migrate with a negative voltage. The two types of particles mix on the display surface to present light gray.

[0049] White display: By driving the white particles in the white channel with a positive voltage, the white particles are completely migrated to the display surface, presenting a pure white color.

[0050] The actual grayscale values ​​of gray2 and white are collected through the feedback module. Actual optical brightness The deviation value is calculated. If it does not exceed the threshold, no parameter adjustment is required. If the deviation exceeds the threshold, the next round is adjusted according to the rules, and the actual status data of yellow and dark yellow refreshed in this round is updated to the spare register.

[0051] The optimized waveform parameters are then fixed into the grayscale-driving scheme mapping table.

[0052] S5) Achieves a pure display of 5-16 colors through multiple rounds of refresh and overlay, and only refreshes the changing areas.

[0053] like Figure 5 This is a comparison diagram of the multi-color display effect between this embodiment and the prior art, wherein... Figure 5 (a) in the figure is the color rendering effect diagram of this embodiment; Figure 5 (b) in the diagram shows the color rendering effect of the prior art. From... Figure 5 It can be seen from this that Figure 5 All target colors (red, yellow, orange, pink, black, white, light and dark gray) in (a) present a pure texture without any impurities or graininess. For example, the red of 50% off is uniform and full, and the orange of Orange has a natural transition without color deviation or color banding.

[0054] Figure 5 In (b), obvious traces of black, white, red, and yellow pixel mixing are visible, with a speckle density of ≥30 dots / mm² upon close inspection. For example, the edges of the red discount sign are covered with black and white speckles, and the orange product name appears blurry due to pixel mixing, resulting in extremely poor color purity.

[0055] The embodiments and descriptions above are merely illustrative of the principles and preferred embodiments of the present invention. Various changes and modifications may be made to the present invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed.

Claims

1. A method for displaying multiple colors by driving a four-color film material with an electronic paper three-color chip, characterized in that, It comprises the following steps: S1), converting the color image to be displayed into a 256 gray scale image, and mapping it to 16 gray scales through a uniform quantization algorithm; each target color corresponds to a unique 16 gray scale value, and the gray scale values of each target color do not overlap; S2), configuring 1bit data IC to compare new and old data patterns, analyzing 0-F hexadecimal data after 16 gray scale modulo through image data algorithm to determine the display change area, and merging pixels with the same driving scheme using a grouping compression algorithm; S3), constructing a gray scale-driving scheme mapping table, and distributing gray scale data to the corresponding registers of the three-color chip through a k-means clustering algorithm; S4), performing multiple rounds of hierarchical refresh, and controlling 2-4 gray scale data in each round of refresh, calling the corresponding driving scheme to drive the particle movement of the four-color film material, and adjusting the basic color depth; After each refresh, the pixel state is obtained to dynamically adjust the waveform parameters in the next round; S5), through multiple rounds of refresh superposition, the pure display of 5-16 colors is realized, and only the change area is refreshed.

2. The method for displaying multiple colors using a three-color chip driving a four-color film material in electronic paper according to claim 1, characterized in that: In step S1), the target colors include black, dark red, red, dark yellow, gray 2, orange, yellow, pink, gray 1, and white, and the corresponding 16 gray scale values are 0, 3, 5, 6, 8, 9, 10, 11, 12, and 15, respectively.

3. The method for displaying multiple colors using a three-color chip driving a four-color film material in electronic paper according to claim 1, characterized in that: In step S2), the 0-F hexadecimal data after 16 gray scale modulo is analyzed through the image data algorithm to determine the display change area, which is as follows: S221), using a row-column scanning algorithm to traverse the hexadecimal data matrix after 16 gray scale modulo, extracting the gray scale value of each pixel, and constructing a current frame gray scale data matrix; S222), using a neighborhood connectivity analysis algorithm to filter isolated single-point change pixels, and obtaining a final change area data matrix after filtering.

4. The method of claim 3, wherein the method is a method of driving a multi-color display of an electronic paper three-color chip four-color film material. In step S2), the grouping compression algorithm is used to merge pixels with the same waveform data, which is as follows: S231), based on the preset gray scale-driving scheme mapping table, traversing the final change area data matrix, and matching the corresponding preliminary driving scheme for each change pixel gray scale value to generate a temporary driving matrix; S232), using a region growing clustering algorithm to group the temporary driving matrix to construct a compressed data frame and realize data compression; S233), generating a compressed data frame for each group; S234), counting the data amount before and after compression, and calculating the compression ratio.

5. The method for displaying multiple colors using a three-color chip driving a four-color film material in electronic paper according to claim 4, characterized in that: In step S232), the region growing clustering algorithm is used to group the temporary driving matrix to construct a compressed data frame and realize data compression, and the specific process is as follows: S2321), initializing a seed pixel queue, starting from the top left corner of the temporary driving matrix, selecting the first unmarked pixel as the seed pixel, and recording its driving scheme; S2322), taking the seed pixel as the center, traversing its neighborhood pixels, judging whether the driving schemes of the neighborhood pixels are consistent, and whether they are change pixels, if so, including them in the current group, and marking them as processed; S2323), repeating step S2322) until there is no new pixel in the current group, and outputting the region coordinates and corresponding driving scheme of the current group; S2324)) continue scanning the matrix, select the next unmarked pixel as a new seed pixel, repeat steps S2322)-S2323) until all changed pixels are grouped.

6. The method for displaying multiple colors using a three-color chip driving a four-color film material in electronic paper according to claim 1, characterized in that: In step S3), the four-color film material is built-in with black, white, red and yellow charged particles, and the particle movement is controlled by voltage direction and time length: positive voltage drives the target particles to migrate to the display surface, reverse voltage drives the target particles to migrate to the inside of the film material, and the voltage time length determines the number of particle migration, thereby presenting different color depth or mixed color.

7. The method for displaying multiple colors using a three-color chip driving a four-color film material in electronic paper according to claim 6, characterized in that: In step S3), the four basic driving schemes and a plurality of mixed driving schemes are included, wherein the basic driving scheme drives the movement of a single particle, and the mixed driving scheme drives the movement of multiple particles. The basic driving scheme includes no change, forward driving, reverse driving, and keeping locked. The mixed driving scheme includes driving combinations corresponding to deep red, pink, deep yellow, orange, gray 1, and gray 2, and different particle mixed driving is realized by combination of the basic driving scheme and voltage parameter optimization.

8. The method for displaying multiple colors using a three-color chip driving a four-color film material in electronic paper according to claim 1, characterized in that: In step S3), the gray scale data is allocated to the corresponding registers of the three-color chip through the k-means clustering algorithm, specifically including the following steps: S31), extract all non-zero gray scale values from the final changed area data matrix, construct a sample data set, and define the feature vector of each sample; S32, set the cluster number according to the number of registers and color coefficients of the three-color chip, and the distribution of refresh rounds ; S33) The elbow rule is used to determine the initial cluster centers, selecting those with the largest differences in feature vectors. One sample was used as the initial center; S34), calculate the Euclidean distance of each sample from each cluster center; allocate each sample to the cluster corresponding to the cluster center with the nearest Euclidean distance, and update the cluster center by taking the mean value of the feature vectors of all samples in the cluster; Repeat the steps of Euclidean distance calculation, sample allocation, and center update until the change of the cluster center meets the convergence condition, and stop iteration; S35), allocate the converged cluster to the main register of the three-color chip according to the color system, particle channel, and priority of refresh round, and the standby register is used to buffer temporary data and feedback adjustment parameters during the refresh process.

9. A method for displaying multiple colors using a three-color chip driving a four-color film material in electronic paper according to claim 7, characterized in that: In step S4), based on the register allocation result and the driving control of the 1-bit data IC, a 5-round layered refresh process is designed, each round of refresh calls the driving scheme stored in the corresponding register, and the particle movement is driven by voltage to realize color display. After refresh, the pixel state is collected by the feedback module, and the waveform parameters of the next round are dynamically adjusted.

10. A method for displaying multiple colors using a three-color chip driving a four-color film material in electronic paper according to claim 7, characterized in that: In step S4), the same positive driving voltage is bound to any one of white, red, yellow and black particle channels, and the binding relationship is switched by register instruction to realize differential driving of different color particles by the same voltage driving logic. In the first round of forward driving, the white channel is bound to drive white particles, and in the second round of forward driving, the red channel is bound to drive red particles. After each round of refresh, the actual gray scale value and actual optical brightness of the pixel are collected by the feedback module, and the deviation value is calculated by comparing with the target value. If the deviation value exceeds the preset threshold, the voltage time length of the corresponding driving scheme in the next round is adjusted according to the rules.

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