Image crosstalk compensation apparatus and method for a backlight modulation type naked-eye three-dimensional display

Abstract

The application relates to the technical field of three-dimensional image display, and discloses an image crosstalk compensation device and method of a backlight modulation type naked-eye three-dimensional display. The device comprises a depth camera, a control unit, a liquid crystal panel, a lens array, a liquid crystal light valve and a backlight source which are sequentially stacked along the propagation direction of the light path. The control unit is configured to store a crosstalk model and a corresponding compensation lookup table which are established in advance based on the optical characteristics of the device; receive eye position information collected by the depth camera; generate and output a driving signal based on the eye position information, binocular image data to be displayed and a brightness compensation lookup table, so as to synchronously control the switching of the backlight source, the local modulation state of the liquid crystal light valve and the gray value of the displayed image on the liquid crystal panel. The application establishes a nonlinear reverse compensation model, and combines the lookup table and the control unit to convert the nonlinear reverse compensation model into high-precision compensation which can be run in real time, so that the depth sense, the definition and the stability of the naked-eye three-dimensional display picture are effectively improved.

Description

Technical Field

[0001] This application relates to the field of three-dimensional image display technology, and in particular to an image crosstalk compensation device and method for a backlight-modulated naked-eye three-dimensional display. Background Technology

[0002] Existing glasses-free 3D display devices generally employ spatial light field modulation methods using optical beam-splitting structures (such as lenticular lenses, cylindrical gratings, light-guided backlights, or light field backlights) to guide images from the display panel to multiple different spatial viewpoint regions, thereby achieving multi-viewpoint 3D display. However, due to physical limitations of the optical structure, manufacturing errors, optical non-ideals of the backlight devices, and the angular diffusion effect of directional light output, there is a non-negligible brightness leakage between viewpoints in the actual output light field, known as "brightness crosstalk." This crosstalk typically manifests as the image brightness portion corresponding to a certain viewpoint being superimposed with luminous flux from other viewpoint directions, resulting in problems such as ghosting, blurred outlines, and depth drift in the displayed image. Furthermore, the spatial response non-uniformity of the backlight driving circuit, the differences in grayscale transmittance characteristics of the liquid crystal panel, and the time response deviation of the time-multiplexed backlight scheme further exacerbate crosstalk, especially in low-brightness areas.

[0003] Traditional crosstalk modeling methods typically assume a linear relationship between crosstalk and brightness and attempt to compensate for brightness by inversely calculating a linear matrix. However, numerous experiments have shown that brightness crosstalk generated by naked-eye 3D backlighting exhibits highly nonlinear characteristics, and its extent depends not only on the brightness of the non-intended viewpoint but also closely on the brightness of the intended viewpoint, displaying complex bivariate coupling properties. Because this characteristic cannot be accurately described by a linear model, existing methods suffer from significant shortcomings in compensation accuracy, especially prone to compensation failure or overcompensation in dark regions.

[0004] Therefore, it is necessary to provide a bivariate nonlinear crosstalk model that can truly reflect the backlight brightness leakage law of the light field, and to propose a compensation algorithm and device architecture that can perform reversible solution in the brightness space and is suitable for real-time display pipelines, so as to overcome the limitations of existing technologies and improve the depth, clarity and stability of naked-eye 3D display images. Summary of the Invention

[0005] The purpose of this invention is to address at least one deficiency in the existing technology and to provide an image crosstalk compensation device and method for a backlight-modulated naked-eye 3D display. This invention establishes a nonlinear inverse compensation model and combines it with a lookup table and a synchronous control system to transform it into a high-precision compensation that can run in real time, effectively improving the depth, clarity and stability of the naked-eye 3D display.

[0006] To achieve the above objectives, in a first aspect, the present invention provides an image crosstalk compensation device for a backlight-modulated naked-eye 3D display. The device includes a depth camera, a control unit, a liquid crystal panel, a lens array, a liquid crystal light valve, and a backlight source. The backlight source, the liquid crystal light valve, the lens array, and the liquid crystal panel are sequentially stacked along the optical path propagation direction. The control unit is electrically connected to the depth camera, the liquid crystal light valve, the backlight source, and the liquid crystal panel. The control unit is configured to: store a crosstalk model pre-established based on the optical characteristics of the device and a corresponding brightness compensation lookup table; receive eye position information acquired by the depth camera; and generate and output a driving signal based on the eye position information, the binocular image data to be displayed, and the brightness compensation lookup table to synchronously control the switching of the backlight source, the local modulation state of the liquid crystal light valve, and the grayscale value of the image displayed on the liquid crystal panel.

[0007] In a second aspect, the present invention provides an image crosstalk compensation method for a backlight-modulated naked-eye 3D display, the method being based on the apparatus described in the first aspect, the method comprising: Obtain the intended viewpoint image of the current frame to be displayed and the non-intended viewpoint image displayed in the previous moment; For each color channel of each pixel in the image, the grayscale value of the non-intended viewpoint image at the pixel position and the grayscale value of the intended viewpoint image at the pixel position and the color channel is used as a two-dimensional index to query the crosstalk compensation lookup table to obtain the compensated grayscale value of the pixel in that channel. Based on the compensated grayscale values ​​of all pixels in all color channels, the compensated intentional viewpoint image is reconstructed. The compensated intended viewpoint image drives the liquid crystal panel to display the image, and simultaneously controls the backlight and liquid crystal light valve so that the backlight illumination area and the liquid crystal light valve illumination area match the currently displayed viewpoint image, thereby achieving naked-eye 3D display after crosstalk suppression.

[0008] Furthermore, constructing the crosstalk compensation lookup table specifically includes: For each pair of grayscale values ​​from the previous frame and the current frame, the corresponding brightness values ​​are converted using the display's gamma characteristic curve. Substitute the converted brightness value into the reverse brightness compensation formula to calculate the compensated brightness value. The compensated brightness value is inversely mapped using the inverse gamma correction formula to obtain the corresponding gray value. The grayscale value corresponding to the compensated brightness value is stored in a lookup table indexed by the positions of the grayscale values ​​of the previous frame and the current frame, thus completing the construction of the crosstalk compensation lookup table.

[0009] Furthermore, the reverse brightness compensation formula is as follows:

[0010] in, For the intended viewpoint brightness, The expected brightness for the intended viewpoint. Expected brightness from a non-intended viewpoint. Let be a bivariate crosstalk function, where, when When the intended viewpoint brightness is, then For unintended viewpoint brightness, when When the brightness is not intended for the viewpoint, then For the intended viewpoint brightness, These are the coordinates of the pixel.

[0011] Furthermore, the inverse gamma correction formula is as follows:

[0012] in, For the intended viewpoint brightness, Grayscale value This is the darkest brightness setting for the LCD. This is the brightest setting for the LCD screen. This represents the maximum grayscale value. To display gamma.

[0013] Furthermore, the bivariate crosstalk function Constructed from luminance matching data obtained based on luminance measurements, this function describes the coupling effect of luminous flux from a non-intended viewpoint on the luminance of the intended viewpoint. The luminance measurement includes: in a controlled lighting environment, having an observer perform luminance and chromaticity matching between the intended luminance and the actual observed luminance affected by crosstalk, and determining the crosstalk amount under the corresponding luminance combination through the matching difference, so as to construct the crosstalk function.

[0014] Furthermore, the bivariate crosstalk function The independent variables include the intended viewpoint brightness and the non-intention viewpoint brightness, and corresponding crosstalk functions are established for different color channels. , , Specifically, it is expressed as follows:

[0015]

[0016]

[0017] in, , , These are the global pixel-by-pixel left and right viewpoint brightness values ​​for the R, G, and B channels, respectively.

[0018] Furthermore, prior to the inverse mapping, the calculated compensated luminance value is preprocessed, including linear luminance compression and nonlinear dark area enhancement.

[0019] Furthermore, the preprocessing first performs linear luminance compression, followed by nonlinear shadow enhancement, wherein the calculation formula for the linear luminance compression is as follows:

[0020] The formula for calculating the nonlinear dark area enhancement is as follows:

[0021] It is a constant, and , This is a preset threshold.

[0022] Thirdly, the present invention also provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the steps of the method described in the second aspect.

[0023] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention constructs a nonlinear crosstalk model, avoiding the shortcomings of traditional linear models that cannot accurately describe the complex coupling changes between arbitrary crosstalk patterns and unintended brightness. It accurately characterizes the nonlinear leakage that easily occurs in dark areas, eliminating image ghosting and outline blurring, significantly improving the depth stability and visual clarity of stereoscopic images, thereby effectively improving compensation accuracy. Simultaneously, this invention combines pre-computation and lookup table mechanisms, transforming complex nonlinear inverse calculations into a lookup operation on the grayscale combination of the previous and current frames. This satisfies the processing speed requirements of backlight modulation displays without sacrificing compensation accuracy, achieving a balance between algorithm accuracy and system real-time performance. Furthermore, through depth camera eye tracking and synchronous dynamic control of the backlight, light valve, and panel, it achieves synergy between optical modulation and image compensation, jointly suppressing crosstalk from both light source guidance and signal correction levels, ultimately improving the depth perception, clarity, and stability of naked-eye 3D displays. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a structural diagram of an image crosstalk compensation device for a backlight modulation naked-eye 3D display according to Embodiment 1 of the present invention; Figure 2 This is a flowchart of an image crosstalk compensation method for a backlight modulation naked-eye 3D display according to Embodiment 2 of this aspect; Figure 3 This is a schematic diagram of the bivariate crosstalk function measurement in Embodiment 2 of the present invention; Figure 4 This is a schematic diagram illustrating the effect of the image crosstalk compensation method in Embodiment 2 of the present invention; Figure 5 This is a schematic diagram of the global crosstalk distribution of a binocular naked-eye 3D display according to Embodiment 2 of the present invention; Explanation of icon numbers: 11. Depth camera; 12. Control unit; 13. LCD panel; 14. Lens array; 15. LCD light valve; 16. Backlight. Detailed Implementation

[0026] To enable those skilled in the art to better understand the present invention, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are merely some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention. It should be understood that the various steps described in the method embodiments of the present invention can be performed in different orders and / or in parallel. Furthermore, the method embodiments may include additional steps and / or omit the steps shown. The scope of the present invention is not limited in this respect.

[0027] The term "comprising" and its variations as used herein are open-ended inclusions, meaning "including but not limited to". The term "based on" means "at least partially based on". The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one additional embodiment"; the term "some embodiments" means "at least some embodiments". Definitions of other terms will be given in the description below.

[0028] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0029] It should be noted that the terms "a" and "a plurality of" used in this invention are illustrative rather than restrictive. Those skilled in the art should understand that, unless otherwise expressly indicated in the context, they should be understood as "one or more".

[0030] The names of the messages or information exchanged between the multiple devices in the embodiments of the present invention are for illustrative purposes only and are not intended to limit the scope of these messages or information.

[0031] Example 1 Please see Figure 1 This invention discloses a preferred embodiment of an image crosstalk compensation device for a backlight-modulated naked-eye 3D display. The device includes a depth camera 11, a control unit 12, a liquid crystal panel 13, a lens array 14, a liquid crystal light valve 15, and a backlight 16. The backlight 16, the liquid crystal light valve 15, the lens array 14, and the liquid crystal panel 13 are stacked sequentially along the optical path. The control unit 12 is electrically connected to the depth camera 11, the liquid crystal light valve 15, the backlight 16, and the liquid crystal panel 13. The control unit 12 is configured to: store a crosstalk model pre-established based on the optical characteristics of the device and a corresponding brightness compensation lookup table; receive eye position information collected by the depth camera 11; and generate and output a driving signal based on the eye position information, the binocular image data to be displayed, and the brightness compensation lookup table to synchronously control the switching of the backlight 16, the local modulation state of the liquid crystal light valve 15, and the grayscale value of the image displayed on the liquid crystal panel 13.

[0032] This invention constructs a nonlinear crosstalk model, avoiding the shortcomings of traditional linear models that cannot accurately describe the complex coupling changes between arbitrary crosstalk patterns and unintended brightness. It accurately characterizes the nonlinear leakage that easily occurs in dark areas, eliminating image ghosting and outline blurring, significantly improving the depth stability and visual clarity of stereoscopic images, thereby effectively improving compensation accuracy. Simultaneously, this invention combines pre-computation and lookup table mechanisms, transforming complex nonlinear inverse calculations into a lookup operation on the grayscale combination of the previous and current frames. This satisfies the processing speed requirements of backlight modulation displays without sacrificing compensation accuracy, achieving a balance between algorithm accuracy and system real-time performance. Furthermore, through depth camera eye tracking and synchronous dynamic control of the backlight, light valve, and panel, it achieves synergy between optical modulation and image compensation, jointly suppressing crosstalk from both light source guidance and signal correction levels, ultimately improving the depth perception, clarity, and stability of naked-eye 3D displays.

[0033] In an optional embodiment, the backlight 16 serves as the light source for the entire 3D display, typically employing an LED surface light source or other light sources with high brightness uniformity. A liquid crystal light valve 15 is positioned directly above the backlight 16, its function being to finely modulate the backlight at the sub-pixel or region level. Driven by the control unit 12, the liquid crystal light valve 15 can quickly and accurately open or close specific micro-areas, thereby cooperating with the lens array 14 to form a directional beam pointing towards the viewer's left or right eye. The lens array 14 is typically a cylindrical lens array or a microlens array, closely fitted above the liquid crystal light valve 15. Its main function is to collimate and direct the light modulated by the liquid crystal light valve 15, precisely projecting light from different light valve openings onto the corresponding viewpoint area in space. The liquid crystal panel 13, located on the top layer of the optical stack, is used to load and display image content. The grayscale value of the displayed image is driven by the control unit 12 based on crosstalk compensation results. A depth camera 11, positioned in front of the display device, is used to collect real-time eye position information of the viewer, including the three-dimensional coordinates of both eyes in space. This information is crucial for dynamically adjusting the backlight direction and achieving personalized viewpoint matching. Control unit 12: This is the core processing and control hub of the device, typically composed of a high-performance processor (such as an FPGA, ASIC, or dedicated display chip) and memory. Its functional configuration is key to implementing the crosstalk compensation method in this embodiment. During operation, the above components work collaboratively under the synchronous drive of control unit 12: the depth camera 11 continuously tracks the human eye; control unit 12 performs crosstalk compensation calculations based on eye position and the image to be displayed by looking up a table, and synchronously generates three control signals; the backlight 16, liquid crystal light valve 15, and liquid crystal panel 13 operate synchronously according to these signals—the backlight illumination area, the light valve opening shape, and the panel display image are spatiotemporally matched, jointly projecting a clear image with crosstalk suppression accurately into the viewer's corresponding eye. By rapidly alternating this process between the left and right eyes, a low-crosstalk, high-definition naked-eye 3D display effect is ultimately achieved.

[0034] Example 2 Please see Figure 2 An image crosstalk compensation method for a backlight-modulated naked-eye 3D display according to an embodiment of the present invention, the method being based on the apparatus described in Embodiment 1, the method comprising: S1: Obtain the intended viewpoint image of the current frame to be displayed and the non-intended viewpoint image (i.e., the leaked viewpoint image) displayed in the previous moment; S2: For each color channel of each pixel in the image, use the gray value of the non-intended viewpoint image at the pixel position and the gray value of the color channel at the pixel position and the gray value of the intended viewpoint image at the pixel position and the color channel as a two-dimensional index to query the crosstalk compensation lookup table and obtain the compensated gray value of the pixel in the channel. S3: Based on the compensated grayscale values ​​of all pixels in all color channels, reconstruct and generate the compensated intentional viewpoint image; S4: Drive the compensated intended viewpoint image to display the image on the liquid crystal panel, and simultaneously control the backlight and the liquid crystal light valve so that the backlight illumination area and the liquid crystal light valve illumination area match the currently displayed viewpoint image, thereby achieving naked-eye 3D display after crosstalk suppression.

[0035] This embodiment constructs a nonlinear crosstalk model, avoiding the shortcomings of traditional linear models that cannot accurately describe the complex coupling changes between arbitrary crosstalk patterns and unintended brightness. It accurately characterizes the nonlinear leakage that easily occurs in dark areas, eliminating image ghosting and outline blurring, significantly improving the depth stability and visual clarity of stereoscopic images, thereby effectively improving compensation accuracy. Simultaneously, this invention combines pre-computation and lookup table mechanisms, transforming complex nonlinear inverse calculations into a lookup operation on the grayscale combination of the previous and current frames. This satisfies the processing speed requirements of backlight modulation displays without sacrificing compensation accuracy, achieving a balance between algorithm accuracy and system real-time performance. Furthermore, through depth camera eye tracking and synchronous dynamic control of the backlight, light valve, and panel, it achieves synergy between optical modulation and image compensation, jointly suppressing crosstalk from both light source guidance and signal correction levels, ultimately improving the depth perception, clarity, and stability of naked-eye 3D display images.

[0036] In an optional embodiment, in step S1, the naked-eye 3D display uses time-division multiplexing to high-speed alternately display left and right eye images. The intended viewpoint image of the current frame to be displayed comes directly from the input binocular video stream (such as the right eye image to be displayed in the next frame), while the non-intended viewpoint image displayed in the previous moment is read from the frame buffer (such as the left eye image that has just been displayed). The control unit 12 maintains this frame buffer to ensure that each pixel being processed is provided with its corresponding intended and non-intended grayscale data for subsequent lookup and compensation.

[0037] In an optional embodiment, in step S2, constructing the crosstalk compensation lookup table specifically includes: (1). For each pair of grayscale values ​​of the previous frame and the current frame, convert them into corresponding brightness values ​​using the display's gamma characteristic curve; (2) Substitute the converted brightness value into the inverse brightness compensation formula (i.e., crosstalk model) to calculate the compensated brightness value, and ensure that the compensated brightness value meets the error threshold condition; crosstalk compensation is performed pixel by pixel to be suitable for real-time display driving of binocular images. The inverse brightness compensation formula is as follows:

[0038] in, For the intended viewpoint brightness, The expected brightness for the intended viewpoint. Expected brightness from a non-intended viewpoint. Let be a bivariate crosstalk function, where, when When the intended viewpoint brightness is, then For unintended viewpoint brightness, when When the brightness is not intended for the viewpoint, then For the intended viewpoint brightness, These are the coordinates of the pixel. Please refer to [link / reference]. Figure 3 The bivariate crosstalk function Constructed from luminance matching data obtained through luminance measurements, this function describes the coupling effect of luminous flux from a non-intended viewpoint on the luminance of the intended viewpoint. The luminance measurement includes: under controlled lighting conditions, having an observer perform luminance and chromaticity matching between the intended luminance and the actual observed luminance affected by crosstalk; determining the crosstalk amount under the corresponding luminance combination through the matching difference; and constructing the crosstalk function. The bivariate crosstalk function... The independent variables include the intended viewpoint brightness and the non-intention viewpoint brightness. Different color channels have different crosstalk values, so a corresponding crosstalk function is established for each color channel. , , Specifically, it is expressed as follows:

[0039]

[0040]

[0041] in, , , These are the global pixel-by-pixel left and right viewpoint brightness values ​​for the R, G, and B channels, respectively. A bivariate crosstalk function is used to obtain a continuous crosstalk distribution covering the entire display brightness range by sampling each pixel brightness point. See details... Figure 5 .

[0042] (3) The compensated brightness value is inversely mapped using the inverse gamma correction formula to obtain the corresponding grayscale value; the inverse gamma correction formula is as follows:

[0043] in, For the intended viewpoint brightness, Grayscale value This represents the darkest brightness (black level) of the LCD. This represents the maximum brightness (white level) of the LCD. This represents the maximum grayscale value. To display gamma.

[0044] (4) Store the grayscale values ​​corresponding to the compensated brightness values ​​in a lookup table indexed by the positions of the grayscale values ​​of the previous and current frames, thus completing the construction of the crosstalk compensation lookup table. A typical lookup table is shown in Table 1 below: Table 1: Typical lookup tables

[0045] In the above mapping table lut, the value stored in lut[0][1] is the output gray value corresponding to the input combination that the gray level of the previous frame is 0 and the gray level of the current frame is 1. Crosstalk compensation lookup tables usually exist in the form of data structures such as lists and dictionaries, and are stored in the heap. Batch data is organized through key-value pairs or indexes to achieve fast query.

[0046] Furthermore, prior to the inverse mapping, the calculated compensated luminance values ​​are preprocessed. This preprocessing includes linear luminance compression and nonlinear shadow enhancement. The preprocessing first performs linear luminance compression, followed by nonlinear shadow enhancement. The formula for linear luminance compression is as follows:

[0047] The formula for calculating the nonlinear dark area enhancement is as follows:

[0048] It is a constant, and , This is a preset threshold.

[0049] This embodiment preprocesses the calculated compensated brightness value, and linear brightness compression is achieved through a coefficient. The overall input brightness is reduced to allow for a dynamic range in subsequent compensation calculations, preventing brightness overflow in bright areas due to compensation stacking, thus avoiding loss of highlight details and overexposure. Secondly, non-linear shadow enhancement will be below the threshold. The forced increase in extreme darkness significantly enhances the distinguishability and compensation accuracy of grayscale in dark areas, effectively solving the problem of compensation failure or overcompensation in dark regions. This ensures that crosstalk compensation can be performed stably and reliably across the entire brightness range.

[0050] In an optional embodiment, in step S3, after completing the point-by-point lookup table compensation for the R, G, and B color channels of all pixels, the control unit 12 recombines and encapsulates the three independent compensated grayscale data matrices obtained according to the original spatial pixel positions and corresponding color channels to generate a complete compensated digital image containing all color information (i.e., the compensated intended viewpoint image), and sends it to the display frame buffer. By efficiently and accurately integrating the pixel data processed discretely and separately in the preceding steps into a complete image frame that can be directly driven by the liquid crystal panel, the spatial and color integrity of the compensation result is ensured. This is the key transformation from algorithm data to a displayable image, ultimately outputting a high-quality 3D image with no ghosting and accurate color reproduction.

[0051] In an optional embodiment, in step S4, the control unit 12 converts the compensated intended viewpoint image (e.g., the right eye image) into a driving signal for the liquid crystal panel 13, and synchronously generates two control signals based on the eye position coordinates provided in real time by the depth camera 11: one control the backlight 16 to illuminate at the corresponding moment, and the other control the liquid crystal light valve 15 to open the illuminated area that precisely matches the spatial position of the current viewpoint (right eye). This allows the light from the backlight to be directionally modulated by the light valve, and then collimated by the lens array 14, precisely illuminating the area on the liquid crystal panel displaying the compensated image, and accurately projecting the light of the image to the viewer's corresponding eye. The effect of the crosstalk compensation method of the present invention is shown in [the diagram]. Figure 4 .

[0052] This embodiment achieves spatiotemporal coordination between image signal compensation and optical hardware modulation. Through synchronous driving, the system not only corrects brightness deviations caused by crosstalk at the signal source, but also precisely guides the corrected image light rays to the target viewpoint along the physical optical path, thus forming a dual crosstalk suppression mechanism in both the "source" and "path" dimensions. This integrated dynamic control ensures that the system maintains a low crosstalk state regardless of changes in the viewer's position, thereby significantly improving the separation, depth stability, and overall visual comfort of the stereoscopic image.

[0053] Example 3 This invention also provides a computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the steps of the method described in Embodiment 2.

[0054] In this embodiment, the computer-readable storage medium may be a tangible medium that may contain or store a computer program for use by or in conjunction with an instruction execution system, apparatus, or device. The computer-readable storage medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination of the foregoing. Alternatively, the computer-readable storage medium may be a machine-readable signal medium. More specific examples of machine-readable storage media include electrical connections based on one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fibers, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination of the foregoing.

[0055] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. An image crosstalk compensation device for a backlight modulation type naked-eye 3D display, characterized in that, The device includes a depth camera (11), a control unit (12), a liquid crystal panel (13), a lens array (14), a liquid crystal light valve (15), and a backlight (16). The backlight (16), the liquid crystal light valve (15), the lens array (14), and the liquid crystal panel (13) are stacked sequentially along the light path propagation direction. The control unit (12) is electrically connected to the depth camera (11), the liquid crystal light valve (15), the backlight (16), and the liquid crystal panel (13). The control unit (12) is configured to store a crosstalk model and a corresponding brightness compensation lookup table pre-established based on the optical characteristics of the device; wherein, the crosstalk model includes bivariate crosstalk functions established for the R, G, and B color channels respectively, the bivariate crosstalk functions take the intention viewpoint brightness and the non-intention viewpoint brightness as independent variables, are used to describe the coupling effect of the luminous flux of the non-intention viewpoint on the intention viewpoint brightness, and are constructed from the brightness matching data obtained by performing brightness and chromaticity matching between the intention brightness and the actual observed brightness affected by crosstalk under controlled lighting conditions; The brightness compensation lookup table is for each color channel of each pixel in the image. It uses the gray values ​​of the non-intended viewpoint image at the corresponding pixel position and color channel and the gray values ​​of the intended viewpoint image at the corresponding pixel position and color channel as two-dimensional indexes, and stores the compensated gray values ​​obtained by gamma characteristic curve conversion, reverse brightness compensation based on the bivariate crosstalk function of the corresponding color channel, and inverse gamma correction. The control unit (12) is further configured to: receive eye position information collected by the depth camera (11), and determine the liquid crystal light valve illumination area that matches the current intended viewpoint to be displayed based on the eye position information; acquire the intended viewpoint image of the current frame to be displayed and the non-intended viewpoint image displayed at the previous moment; query the brightness compensation lookup table for each color channel of each pixel, and reconstruct the compensated intended viewpoint image; and generate and output a driving signal based on the compensated intended viewpoint image and the eye position information to synchronously control the switching of the backlight (16), the illumination area of ​​the liquid crystal light valve (15), and the grayscale value of the image displayed on the liquid crystal panel (13), so that the backlight illumination area and the liquid crystal light valve illumination area match the currently displayed viewpoint image.

2. A method for image crosstalk compensation in a backlight-modulated naked-eye 3D display, the method being based on the apparatus of claim 1, characterized in that, The method includes: The eye position information collected by the depth camera is acquired, and the liquid crystal light valve illumination area that matches the intended viewpoint to be displayed is determined based on the eye position information. Obtain the intended viewpoint image of the current frame to be displayed and the non-intended viewpoint image displayed in the previous moment; For each color channel of each pixel in the image, the gray value of the non-intended viewpoint image at the pixel position and the gray value of the color channel at the intended viewpoint image at the pixel position and the gray value of the color channel at the intended viewpoint image is used as a two-dimensional index to query the brightness compensation lookup table to obtain the compensated gray value of the pixel in the color channel. Based on the compensated grayscale values ​​of all pixels in all color channels, the compensated intentional viewpoint image is reconstructed. The compensated intended viewpoint image is used to drive the liquid crystal panel to display an image, and the backlight and the liquid crystal light valve are controlled synchronously to match the backlight illumination area and the liquid crystal light valve illumination area with the currently displayed viewpoint image. The brightness compensation lookup table is pre-constructed in the following manner: For each pair of grayscale values ​​from the previous frame and the current frame, the corresponding brightness value is converted using the display's gamma characteristic curve. Substituting the converted brightness value into the inverse brightness compensation formula, the compensated intended viewpoint brightness is calculated. The inverse brightness compensation formula is as follows: Where L_observed(x,y) is the intended viewpoint brightness obtained after inverse brightness compensation, LIntended(x,y) is the expected brightness of the intended viewpoint, LunIntended(x,y) is the expected brightness of the non-intended viewpoint, CT(Lr(x,y),Ll(x,y)) is a bivariate crosstalk function, and (x,y) is the coordinate of the pixel. When the right viewpoint is the intended viewpoint, Lr(x,y) is the intended viewpoint brightness and Ll(x,y) is the non-intended viewpoint brightness; when the left viewpoint is the intended viewpoint, Ll(x,y) is the intended viewpoint brightness and Lr(x,y) is the non-intended viewpoint brightness. The bivariate crosstalk function uses the intended viewpoint brightness and the non-intentional viewpoint brightness as independent variables to describe the coupling effect of the luminous flux of the non-intentional viewpoint on the intended viewpoint brightness. The bivariate crosstalk function is constructed from brightness matching data obtained based on brightness measurement. The brightness measurement includes: performing brightness and chromaticity matching between the intended brightness and the actual observed brightness affected by crosstalk under controlled lighting conditions, and determining the crosstalk amount under the corresponding brightness combination through the matching difference; and establishing corresponding bivariate crosstalk functions for the R, G, and B color channels respectively. The compensated intentional viewpoint brightness is inversely mapped using the inverse gamma correction formula to obtain the corresponding compensated grayscale value. The compensated grayscale value is stored at the position indexed by the grayscale value of the previous frame and the grayscale value of the current frame, thus completing the construction of the brightness compensation lookup table.

3. The method according to claim 2, characterized in that, The inverse gamma correction formula is as follows: Where L_observed(x,y) is the intended viewpoint brightness obtained after inverse brightness compensation, G(x,y) is the grayscale value, L_min(x,y) is the darkest brightness of the liquid crystal, L_max(x,y) is the brightest brightness of the liquid crystal, G_max(x,y) is the maximum grayscale value, and γ is the display gamma.

4. The method according to claim 3, characterized in that, Prior to the inverse mapping, the calculated compensated intentional viewpoint brightness is preprocessed, including linear brightness compression and nonlinear dark area enhancement.

5. The method according to claim 4, characterized in that, The preprocessing first performs linear brightness compression, followed by nonlinear shadow enhancement. The calculation formula for the linear brightness compression is as follows: The formula for calculating the nonlinear dark area enhancement is as follows: It is a constant, and , This is a preset threshold.

6. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 2 to 5.

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