Split-screen synchronous display method for electrophoresis electronic paper and electrowetting electronic paper

Abstract

The invention discloses a split-screen synchronous display method for electrophoresis electronic paper and electrowetting electronic paper. The method comprises the following steps: S1, receiving a video stream output by an external video source; s2, converting the video stream into a parallel RGB (Red, Green, Blue) data stream; s3, performing inter-frame difference calculation on the parallel RGB data stream to generate a frame difference data stream; s4, asynchronously caching the frame difference data stream to adapt to the difference between the output frame rate of the external video source and the refresh rate of the electronic paper display equipment; s5, based on the asynchronously cached frame difference data flow, respectively generating driving signals suitable for the electrophoresis electronic paper and the electrowetting electronic paper; and S6, respectively outputting the driving signals to the electrophoresis electronic paper display equipment and the electrowetting electronic paper display equipment so as to realize synchronous split-screen display. According to the invention, multiple problems in real-time dynamic display of the existing electronic paper are solved.

Description

Technical Field

[0001] This invention relates to the field of digital circuit design technology, and in particular to a method for simultaneous split-screen display of electrophoretic electronic paper and electrowetting electronic paper. Background Technology

[0002] In the field of reflective display technology, electrophoretic electronic paper and electrowetting electronic paper are two highly regarded and representative technological approaches.

[0003] Electrophoretic electronic paper, commonly used in e-book readers, works by using an external electric field to orient black and white particles with opposite polarities within microcapsules, thus switching the brightness of pixels. The most significant feature of this technology is its bistable characteristic: once the particles reach their target position, they maintain a stable alignment for an extended period even after the external electric field is removed. This means the screen only consumes power during image content switching, with negligible power consumption during static display. This characteristic provides a near-paper-like visual experience and extremely high energy efficiency, making it ideal for static applications requiring extended reading. However, due to limitations in particle migration speed, electrophoretic technology has a relatively low overall refresh rate, making it difficult to achieve smooth dynamic image rendering, such as smooth video playback. This largely limits its application to the realm of "e-books" or "electronic tags," which primarily consist of text and static images.

[0004] In contrast, electrowetting electronic paper technology's display mechanism is based on the electrowetting effect. Within each pixel unit, there exists a colored oil film and a hydrophobic insulating layer. When voltage is applied, the solid-liquid interfacial tension changes, causing the colored oil film to shrink, thus exposing the underlying hydrophilic white substrate. Alternatively, after the voltage is removed, the oil film redistributes and covers the substrate, thereby controlling the brightness and color of the pixel. In this technology, the fluid movement response speed is much faster than the migration of electrophoretic particles, thus enabling a high refresh rate sufficient to support the playback of animation and even standard frame rate video. Furthermore, through pixel structure design and ink color matching, electrowetting technology has the potential to achieve vibrant color displays, broadening its application possibilities. However, its display state typically lacks perfect bistableness. Maintaining dynamic content display or certain static states may require continuous or intermittent power input, resulting in higher average power consumption than electrophoretic electronic paper. Moreover, its manufacturing process and supply chain maturity are currently relatively low.

[0005] Currently, in the research and product development stages, the content updates of display modules for both electrophoretic and electrowetting electronic paper generally rely on pre-stored solutions. A typical approach is to pre-store the image sequences or video files to be displayed locally on the display device or on a removable storage medium (such as an SD card), which is then called and played by the controller within the device according to a predetermined process. This content delivery model has fundamental limitations. First, it cannot support real-time control and content updates. Once the display content is fixed, it is difficult to modify, replace, or dynamically change in response to external commands without physical contact with the storage medium, limiting its application in scenarios requiring remote updates, interactive information display, or real-time data visualization. Second, existing technologies lack direct, efficient, real-time communication and driving capabilities with host computers (such as personal computers, servers, or mobile devices), making it impossible to achieve the real-time generation and push of display signals by the host system, as with traditional displays, thus preventing the use of electronic paper as a real-time controllable extended display terminal. This significantly reduces the flexibility and integration of electronic paper.

[0006] More importantly, existing technologies completely fail to address the cutting-edge issue of how to synergistically utilize the complementary characteristics of electrophoresis and electrowetting display technologies. Specifically, there is no effective display method that can intelligently segment and allocate the same display image or information content based on the differentiated performance requirements (such as refresh rate, color, and power consumption) of different areas. For example, it is impossible to allocate static text and charts to the ultra-low-power electrophoresis display area for persistent display, while simultaneously allocating dynamic charts and video presentations to the high-speed refresh-supporting electrowetting display area for smooth rendering. Existing technologies lack a holistic concept and methodological support for this "split-screen" display mode, especially lacking the core technology chain necessary to achieve "synchronous display" of both. This includes: how to intelligently "crop" and identify content from the same signal source (such as real-time video streams or composite graphical interfaces) to determine the most suitable display technology type for each part; how to perform "frame rate adaptation" and drive waveform optimization based on the distinctly different response characteristics of electrophoresis and electrowetting, ensuring that dynamic content flows smoothly in the electrowetting area while static content remains stable and low-power in the electrophoresis area; and finally, how to ensure, through precise timing and control logic, that two display areas that may be physically integrated on the same screen but differ significantly in driving principles and response speeds can seamlessly collaborate and present a complete, coherent, and unified composite image. The lack of this "cropping-frame rate adaptation-split-screen synchronization" capability means that the advantages of electrophoretic and electrowetting electronic paper can only be utilized in isolation, failing to achieve a "1+1>2" synergistic effect at the system level. This not only restricts the evolution of reflective display technology towards more complex and interactive application scenarios but also hinders the emergence of a new generation of electronic paper devices that combine ultra-low power consumption and dynamic display capabilities.

[0007] Therefore, developing a method that can effectively integrate the advantages of both to achieve real-time content-driven, intelligent split-screen, and synchronous display is key to breaking through current technological bottlenecks and expanding the application boundaries of e-paper. Summary of the Invention

[0008] A method for simultaneous split-screen display of electrophoretic electronic paper and electrowetting electronic paper includes the following steps: S1 receives the video stream output from an external video source; S2 converts the video stream into a parallel RGB data stream; S3 performs inter-frame difference calculation on the parallel RGB data stream to generate a frame difference data stream. In the frame difference data stream, only pixels in the video stream whose grayscale changes exceed a preset threshold are assigned non-zero grayscale change values. S4 asynchronously buffers the frame difference data stream to adapt to the difference between the output frame rate of the external video source and the refresh rate of the electronic paper display device; S5 generates drive signals suitable for electrophoretic electronic paper and electrowetting electronic paper based on the asynchronous buffered frame difference data stream. S6 outputs the driving signal to the electrophoretic electronic paper display device and the electrowetting electronic paper display device respectively to achieve synchronous split-screen display.

[0009] According to embodiments of the present invention, one of the technical solutions has at least one of the following advantages or beneficial effects: This invention provides a complete technical path to solve multiple problems in real-time dynamic display of electronic paper by constructing a method flow of "video stream reception - format conversion - inter-frame differential processing - asynchronous buffering - split-path driving".

[0010] Specifically, this invention first realizes real-time driving of electronic paper by an external standard video source, breaking through the traditional limitation of relying on pre-stored static files and expanding application scenarios.

[0011] Secondly, by introducing inter-frame difference calculation, the driving signal is converted from complete image data of each frame to data containing only the grayscale changes between frames, thus transforming full-screen refresh into partial refresh in principle. This directly addresses and significantly alleviates the problem of large-area visual flicker caused by full-screen updates due to the low refresh rate of e-paper.

[0012] Furthermore, through the asynchronous caching step, this method establishes a buffering and synchronization mechanism between the high-speed input video data stream and the low-speed response electronic paper display, effectively eliminating screen tearing or jumping caused by the difference in rhythm between the two, and ensuring display continuity.

[0013] Finally, the method framework of this invention naturally supports splitting a single video stream and adapting to two electronic papers with different display principles, providing a methodological basis for achieving synchronous comparative display.

[0014] According to one embodiment of the present invention, after receiving the video stream output from an external video source in step S1, the method further includes: providing display identification data to the external video source to force the external video source to output a video stream that matches the physical display parameters of the electrophoretic electronic paper and / or electrowetting electronic paper display device. This step aims to ensure, from the source, that the video stream format (such as resolution and frame rate) is initially matched with the capabilities of the electronic paper, laying the foundation for subsequent processing.

[0015] According to one embodiment of the present invention, the display identification data includes preferred timing information that matches the physical resolution and maximum refresh rate of the electronic paper display device. The present invention guides the video source to output a signal with optimal compatibility by reporting timing parameters that conform to the physical limits of electronic paper.

[0016] According to one embodiment of the present invention, in step S1, receiving a video stream output from an external video source is receiving a video stream output through a high-definition multimedia interface that conforms to the display port protocol or the high-definition multimedia interface protocol. The video stream contains complete desktop image data and corresponding horizontal and vertical synchronization signals.

[0017] According to one embodiment of the present invention, in step S2, the video stream is converted into a parallel RGB data stream by a dedicated bridging module, which performs decoding of the high-definition multimedia interface data and reconstructs it into a data stream in the parallel RGB color space.

[0018] According to one embodiment of the present invention, the dedicated bridging module is an HDMI-RGB bridging module. The HDMI-RGB bridging module stores EDID parameters internally and reports the preferred timing that matches the physical resolution and refresh rate of the EPD / EWD to the computer during the power-on enumeration phase, thereby forcing the computer to output RGB888 parallel data streams with the corresponding resolution and frame rate.

[0019] According to one embodiment of the present invention, step S3, which involves calculating the inter-frame difference of the parallel RGB data stream, specifically includes: Cache the previous frame image of the parallel RGB data stream; Align the current frame image with the cached previous frame image in a timely manner; For two time-aligned images, calculate the absolute difference of grayscale values ​​pixel by pixel; The absolute difference is compared with a preset threshold, and the frame difference data stream is generated based on the comparison result.

[0020] This invention quantifies the degree of change by comparing the grayscale differences at the same location between consecutive frames, and performs binarization or hierarchical processing based on a threshold. Furthermore, the frame difference refresh method can largely utilize the bistable nature of electronic paper to refresh only the changing areas. This avoids unnecessary screen refreshes and greatly reduces the power consumption generated by electronic paper refresh. By refreshing only the changing areas, this method further reduces the number of electric field switching operations, thereby extending the particle lifetime of the electronic paper.

[0021] According to one embodiment of the present invention, the step of calculating the absolute difference of grayscale values ​​pixel by pixel is expressed by the formula ΔGray=|Grayt Gray(t-1) is calculated, where Grayt is the gray value of the pixel in the current frame, and Gray(t-1) is the gray value of the corresponding pixel in the previous frame.

[0022] According to one embodiment of the present invention, generating the frame difference data stream based on the comparison result means: if the absolute difference in grayscale values ​​of pixels is greater than the preset threshold, then a value related to the difference is output at the corresponding position in the frame difference data stream; if it is less than or equal to the preset threshold, then a value indicating that no refresh is needed is output. The method of the present invention allocates driving energy (non-zero values) only to pixels that change significantly, and ignores pixels that do not change or change only slightly (zero values), thus achieving selective refresh.

[0023] According to one embodiment of the present invention, the preset threshold in S3 is a configurable constant used to distinguish between grayscale differences caused by valid changes in video content and invalid differences caused by noise or minor jitter. The present invention establishes a discrimination boundary between signal (real changes) and noise (minor perturbations) by setting a threshold value; changes below this boundary are considered invalid and filtered out.

[0024] According to one embodiment of the present invention, the output value related to the difference refers to directly using the absolute difference in grayscale as the output value; or, mapping the absolute difference in grayscale to one of a preset number of grayscale levels and outputting the representative value corresponding to that level.

[0025] According to one embodiment of the present invention, the asynchronous buffer in S4 is implemented through a video direct memory access module with a multi-buffered structure. The present invention allocates multiple buffers in external memory to implement asynchronous cyclic operations of input and output pointers, isolating different clock domains.

[0026] According to one embodiment of the present invention, the multi-buffering structure in the asynchronous cache is a triple-buffering structure.

[0027] According to one embodiment of the present invention, the asynchronous buffering structure is used to smooth the rate difference between the 60Hz video stream output from the computer and the ≤10Hz refresh rate of the electronic paper display device.

[0028] According to one embodiment of the present invention, before performing the inter-frame difference calculation step on the parallel RGB data stream, the method further includes: extracting data of a target rectangular region from the parallel RGB data stream according to preset clipping parameters, and using the extracted data as input for inter-frame difference calculation.

[0029] According to one embodiment of the present invention, the trimming parameters can be dynamically configured and modified.

[0030] According to one embodiment of the present invention, the preset clipping parameters include frame buffer start address, line span, clipping width, and clipping height.

[0031] According to one embodiment of the present invention, after the asynchronous buffering step in S4 and before the driving signals for generating electrophoretic electronic paper and electrowetting electronic paper in S5, the method further includes: scaling the image corresponding to the frame difference data stream to match the physical resolution of the target electronic paper display device. By adding the image scaling step, the present invention ensures that images from external video sources can be displayed on the electronic paper at full screen or a customized size.

[0032] According to one embodiment of the present invention, the scaling process is bilinear interpolation amplification.

[0033] According to one embodiment of the present invention, in step S5, generating driving signals suitable for electrophoretic electronic paper and electrowetting electronic paper respectively means generating driving waveforms for electrophoretic electronic paper based on electrophoretic grayscale refresh strategy and generating driving waveforms for electrowetting electronic paper based on electrowetting grayscale refresh strategy.

[0034] According to one embodiment of the present invention, the electrophoretic grayscale refresh strategy is a technical solution for driving electrophoretic electronic paper to achieve different grayscale (not just black and white) displays, and its essence is a set of voltage waveform sequences. The waveform of the electrophoretic grayscale refresh strategy consists of multiple stages, including a reset stage, a driving stage, and a stabilization stage. The waveform parameters, which are pre-calculated or optimized for different combinations of initial and target grayscale, are stored in a waveform lookup table in a structured binary data format.

[0035] According to one embodiment of the present invention, the electrowetting grayscale refresh strategy precisely controls the degree of oil film contraction by adjusting the amplitude, pulse width, or frequency of the driving voltage, thereby displaying different grayscale levels. The electrowetting grayscale refresh strategy, based on a pre-stored feature parameter table, adaptively selects a combination of voltage amplitude modulation and / or pulse width modulation according to the target grayscale value and the amount of grayscale change, generating an optimized driving waveform sequence.

[0036] According to one embodiment of the present invention, the external video source is a computer or mobile device, and the video stream is output through a high-definition multimedia interface.

[0037] According to one embodiment of the present invention, the method is executed on a heterogeneous computing platform comprising a programmable logic unit and a processing system; wherein at least some of the operations of the inter-frame difference calculation and asynchronous caching are implemented in hardware logic in the programmable logic unit; and the configuration and / or scaling processing of the pruning parameters are implemented in software in the processing system.

[0038] According to one embodiment of the present invention, the programmable logic unit is the programmable logic portion of an FPGA or a SoC chip.

[0039] According to one embodiment of the present invention, the split-screen can be achieved by configuring different region cropping parameters to route different spatial parts of the same video stream to two driving modules respectively.

[0040] A system for split-screen synchronous display using the aforementioned electrophoretic electronic paper and electrowetting electronic paper method includes: The video stream conversion module is used to receive video streams from external video sources and convert them into parallel RGB data streams; The inter-frame difference processing module, connected to the video stream conversion module, is used to perform inter-frame difference calculation on the parallel RGB data stream to generate a frame difference data stream, wherein only regions in the video stream where the pixel grayscale change exceeds a preset threshold are assigned non-zero grayscale change values ​​in the frame difference data stream. An asynchronous caching module, connected to the inter-frame difference processing module, is used to cache the inter-frame difference data stream to adapt to the difference between the output frame rate of the external video source and the refresh rate of the electronic paper display device. The first driving module, connected to the asynchronous buffer module, is used to generate a driving signal suitable for electrophoretic electronic paper based on the buffered frame difference data stream. The second driving module, connected to the asynchronous buffer module, is used to generate a driving signal suitable for electrowetting electronic paper based on the buffered frame difference data stream.

[0041] According to embodiments of the present invention, one of the technical solutions has at least one of the following advantages or beneficial effects: This invention's system achieves pipelined processing of high-speed video streams through a clear modular division of labor, resulting in high integration and excellent real-time performance. The video stream conversion module handles protocol interaction and signal conversion with the video source, providing a standardized input interface for the system. The inter-frame difference processing module, as the core, performs real-time image data storage, comparison, and threshold determination at the hardware level, generating the local refresh instructions required for driving—a crucial hardware component for suppressing flicker. The asynchronous buffer module, acting as a rate adapter, ensures the integrity and continuity of data when production and consumption rates are mismatched through its multi-buffered structure, eliminating screen tearing from a system resource perspective. Two independent driver modules ensure that the universally processed signal can be accurately translated into two electronic paper-specific electrical languages, achieving the final correct display.

[0042] According to one embodiment of the present invention, the video stream conversion module includes a storage unit storing display identification data, which is used to provide the display identification data to the external video source when powered on, so that the external video source outputs a matching video stream.

[0043] According to one embodiment of the present invention, the inter-frame difference processing module includes: A frame buffer unit is used to buffer the image data of the previous frame; The calculation unit is used to perform temporal alignment and pixel-by-pixel grayscale difference calculation and threshold comparison between the current frame image data and the previous frame image data output by the frame buffer unit.

[0044] According to one embodiment of the present invention, the asynchronous caching module is a cache controller with a multi-buffering structure implemented based on a video direct memory access IP core.

[0045] According to one embodiment of the present invention, the asynchronous caching module includes a first VDMA module and a second VDMA module; the first VDMA module is used to cooperate with the inter-frame difference processing module to cache and read the previous frame image; the second VDMA module is used to receive and cache the inter-frame difference data stream, and provide data to the first driving module and the second driving module respectively.

[0046] According to one embodiment of the present invention, the video direct memory access module receives video data streams through the AXI4-Stream interface and interacts with external memory through the AXI4 main interface to complete the caching of frame data.

[0047] According to one embodiment of the present invention, the buffering of the previous frame image is achieved through the cooperation of a first-in-first-out memory or the read channel of a video direct memory access module, so as to ensure that the previous frame data can be aligned with the current frame data at the pixel level when outputting the previous frame data.

[0048] According to one embodiment of the present invention, the split-screen synchronous display system further includes a region cropping module, which is disposed between the video stream conversion module and the inter-frame difference processing module, and is used to extract target region data from the parallel RGB data stream according to configuration parameters.

[0049] According to one embodiment of the present invention, the split-screen synchronous display system further includes an image scaling module disposed between the asynchronous cache module and the first and second driving modules, for scaling the image corresponding to the frame difference data stream to the target resolution.

[0050] According to one embodiment of the present invention, the split-screen synchronous display system is integrated into a system-on-a-chip including a programmable logic unit and a processing system; wherein the video stream conversion module, the inter-frame difference processing module, and the asynchronous buffer module are at least partially implemented in the programmable logic unit; and the configuration of the region cropping parameters and / or the image scaling processing are at least partially performed by the processing system.

[0051] An electronic device includes the aforementioned split-screen synchronous display system.

[0052] A computer-readable storage medium includes the aforementioned split-screen synchronous display system.

[0053] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the discovery. Attached Figure Description

[0054] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is a flowchart of the method for simultaneous split-screen display of electrophoretic electronic paper and electrowetting electronic paper in the embodiment. Detailed Implementation

[0055] In the description of this invention, the use of terms such as "first," "second," etc., is for the purpose of distinguishing technical features only and should not be construed as indicating or implying relative importance, or implicitly indicating the number of technical features indicated, or implicitly indicating the order of the technical features indicated.

[0056] When a numerical range is disclosed herein, the range is considered continuous and includes the minimum and maximum values ​​of the range, as well as every value between the minimum and maximum values. Furthermore, when the range refers to integers, it includes every integer between the minimum and maximum values ​​of the range. Additionally, when multiple ranges are provided to describe a feature or characteristic, the ranges may be combined. In other words, unless otherwise specified, all ranges disclosed herein should be understood to include any and all subranges to which they are incorporated.

[0057] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of the present invention.

[0058] Unless otherwise specified, the reagents, methods and equipment used in this invention are all conventional reagents, methods and equipment in this technical field.

[0059] Example The flowchart for the split-screen synchronous display method of electrophoretic electronic paper and electrowetting electronic paper is as follows: Figure 1 As shown, it includes the following steps: S1 outputs a video stream conforming to the DP 1.2 / HDMI 1.4b protocol through the HDMI interface on the computer. The video stream contains a complete desktop image and synchronization signal. The HDMI video stream is connected to an HDMI-RGB bridging module. The bridging module stores EDID parameters and reports the preferred timing matching the physical resolution and refresh rate of the EPD / EWD to the computer during the power-on enumeration phase, forcing the computer to output a desktop HDMI data stream with the corresponding resolution and frame rate. The conversion chip within the aforementioned bridging module S2 converts the HDMI data stream into a parallel RGB888 data stream. This RGB888 data stream is then input to the programmable logic (PL) terminal of the ZYNQ-7020 chip at a pixel clock rate. At the PL terminal, the data stream first passes through a custom resolution cropping module, which performs hardware-level cropping of the entire desktop image according to the set starting coordinates and dimensions, retaining only the pixels of the target area. The resulting data stream serves as the input for subsequent processing. Next, instantiate at least two VDMA (Video Direct Memory Access) modules with AXI4-Stream interfaces within the PL. Input the cropped RGB888 data stream into the first VDMA module. Configure this VDMA module, setting its write channel to dynamic synchronous phase-locked master mode and its read channel to dynamic synchronous phase-locked slave mode, so that it can store the input real-time RGB data stream in order into the PS-side DDR3 memory for frame buffering and can read it out in order. S3 runs a region configuration service on the ZYNQ processing system (PS). This service can dynamically modify parameters such as the frame buffer start address and line span of the first VDMA module through the AXI-Lite bus, so as to cooperate with the hardware trimming module in S2 to accurately define the specified rectangular area of ​​the desktop. Meanwhile, the inter-frame difference calculation module is used for processing at the PL end: this module receives two inputs, one is the current frame RGB888 image data input in real time in S2 (after cropping), and the other is the previous frame image data read from the first VDMA module and cached; the inter-frame difference module calls the FIFO IP core to store the previous frame image data and configures its output timing to achieve pixel-by-pixel alignment with the current frame data; Then, the aligned two-frame image data are converted into grayscale images, and the absolute difference in grayscale (ΔGray) is calculated pixel by pixel. Dynamic pixels are assigned hierarchical values ​​based on the magnitude of the ΔGray value, with each level corresponding to a specific numerical value used to associate with different subsequent refresh waveforms. If the ΔGray of a pixel exceeds a preset threshold, the assigned value is output as valid data; otherwise, the pixel data is set to zero. The processed complete frame data (i.e., the "reassigned data") is written to the frame buffer through the next-level VDMA module. At the PL end, S4 uses the second VDMA module to receive the real-time data stream from the inter-frame difference module. At the PS end, the write and read operations of the VDMA module are configured in detail. By configuring its read mode, an appropriate input frame dropping strategy is implemented at the PS end to balance the rate difference between the high frame rate input on the computer and the low refresh rate display on the e-paper, thereby solving the problem of mismatch between the display rates at both ends and achieving stable refresh. At the PS end, S5 performs bilinear interpolation upscaling on the image data buffered by S4, generating upscaled images with the same physical resolution as EPD and EWD. The upscaled image data is then written into two independent frame buffers prepared for EPD and EWD, respectively. The two cached image data streams are sent to the EPD driver module and the EWD driver module, respectively. The EPD driver module generates a driving waveform based on the electrophoretic grayscale refresh strategy, while the EWD driver module generates a driving waveform based on the electrowetting grayscale refresh strategy. The waveforms output by these two driver modules drive the connected electrophoretic electronic paper (EPD) display device and electrowetting electronic paper (EWD) display device, respectively, to achieve synchronous, full-screen display. S6 pre-divides the computer desktop into two logical display areas, left and right. Through the hardware clipping module configuration in S2 and the area configuration service on the PS side in S3, two sets of parameters are set respectively, so that the image data of the left logical display area is presented on the EPD after S2-S5 steps, and the image data of the right logical display area is presented on the EWD after the same S2-S5 steps.

[0060] The above are merely embodiments of the present invention and do not limit the patent scope of the present invention. Any equivalent modifications made based on the content of the present invention specification, or direct or indirect applications in related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A method for simultaneous split-screen display of electrophoretic electronic paper and electrowetting electronic paper, characterized in that: Includes the following steps: S1 receives the video stream output from an external video source; S2 converts the video stream into a parallel RGB data stream; S3 performs inter-frame difference calculation on the parallel RGB data stream to generate a frame difference data stream. In the frame difference data stream, only pixels in the video stream whose grayscale changes exceed a preset threshold are assigned non-zero grayscale change values. S4 asynchronously buffers the frame difference data stream to adapt to the difference between the output frame rate of the external video source and the refresh rate of the electronic paper display device; S5 generates drive signals suitable for electrophoretic electronic paper and electrowetting electronic paper based on the asynchronous buffered frame difference data stream. S6 outputs the driving signal to the electrophoretic electronic paper display device and the electrowetting electronic paper display device respectively to achieve synchronous split-screen display.

2. The method according to claim 1, characterized in that: In step S1, receiving a video stream output from an external video source means receiving a video stream output through a high-definition multimedia interface that conforms to the display port protocol or the high-definition multimedia interface protocol. The video stream contains complete desktop image data and corresponding horizontal and vertical synchronization signals.

3. The method according to claim 1, characterized in that: In step S3, the calculation of inter-frame difference for the parallel RGB data stream specifically includes: Cache the previous frame image of the parallel RGB data stream; Align the current frame image with the cached previous frame image in a timely manner; For two time-aligned images, calculate the absolute difference of grayscale values ​​pixel by pixel; The absolute difference is compared with a preset threshold, and the frame difference data stream is generated based on the comparison result.

4. The method according to claim 1, characterized in that: In step S3, the absolute difference of grayscale values ​​is calculated pixel by pixel using the formula ΔGray=|Grayt Gray(t-1) is calculated, where Grayt is the gray value of the pixel in the current frame, and Gray(t-1) is the gray value of the corresponding pixel in the previous frame.

5. The method according to claim 1, characterized in that: The step of generating the frame difference data stream based on the comparison result means that: if the absolute difference in grayscale of the pixels is greater than the preset threshold, a value related to the difference is output at the corresponding position in the frame difference data stream; if it is less than or equal to the preset threshold, a value indicating that no refresh is required is output.

6. The method according to claim 1, characterized in that: The asynchronous cache mentioned in S4 is implemented through a video direct memory access module with a multi-buffering structure.

7. The method according to claim 1, characterized in that: In step S5, generating driving signals suitable for electrophoretic electronic paper and electrowetting electronic paper respectively means generating driving waveforms for electrophoretic electronic paper based on electrophoretic grayscale refresh strategy and generating driving waveforms for electrowetting electronic paper based on electrowetting grayscale refresh strategy.

8. A system for split-screen synchronous display using the electrophoretic electronic paper and electrowetting electronic paper method according to any one of claims 1 to 7, comprising: The video stream conversion module is used to receive video streams from external video sources and convert them into parallel RGB data streams; The inter-frame difference processing module, connected to the video stream conversion module, is used to perform inter-frame difference calculation on the parallel RGB data stream to generate a frame difference data stream, wherein only regions in the video stream where the pixel grayscale change exceeds a preset threshold are assigned non-zero grayscale change values ​​in the frame difference data stream. An asynchronous caching module, connected to the inter-frame difference processing module, is used to cache the inter-frame difference data stream to adapt to the difference between the output frame rate of the external video source and the refresh rate of the electronic paper display device. The first driving module, connected to the asynchronous buffer module, is used to generate a driving signal suitable for electrophoretic electronic paper based on the buffered frame difference data stream. The second driving module, connected to the asynchronous buffer module, is used to generate a driving signal suitable for electrowetting electronic paper based on the buffered frame difference data stream.

9. The system according to claim 8, characterized in that: The inter-frame difference processing module includes: A frame buffer unit is used to buffer the image data of the previous frame; The calculation unit is used to perform temporal alignment and pixel-by-pixel grayscale difference calculation and threshold comparison between the current frame image data and the previous frame image data output by the frame buffer unit.

10. The system according to claim 8, characterized in that: The asynchronous caching module includes a first VDMA module and a second VDMA module; the first VDMA module is used to cooperate with the inter-frame difference processing module to cache and read the previous frame image; the second VDMA module is used to receive and cache the inter-frame difference data stream, and provide data to the first driving module and the second driving module respectively.

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