A digital display method and system for art exhibition

Abstract

The present invention discloses a digital display method and system for art exhibitions, relating to the field of digital display technology. The method comprises generating a point cloud dataset; reconstructing the point cloud dataset into a grid to generate a three-dimensional digital grid of the exhibit; analyzing the material characteristics of the three-dimensional digital grid of the exhibit to extract a material parameter set; collecting the viewer's position coordinates, calculating the relative azimuth between the viewer and the exhibit based on the viewer's position coordinates, and generating a perspective transformation matrix; applying the perspective transformation matrix to the three-dimensional digital grid of the exhibit, overlaying the material parameter set for rendering, outputting a perspective-transformed image of the exhibit, and synthesizing the exhibit image with the exhibition hall background image into a mixed reality scene; and dynamically updating the perspective transformation matrix based on real-time changes in the viewer's position coordinates to regenerate the mixed reality scene. The present invention employs a multi-sensor collaborative acquisition scheme to significantly improve the accuracy of three-dimensional reconstruction. Furthermore, the invention introduces multispectral structured light illumination technology to accurately capture material characteristics.

Description

Technical Field

[0001] The present invention relates to the field of digital display technology, and in particular to a digital display method and system for art exhibitions. Background Art

[0002] With the rapid development of digital technology, the art exhibition sector is facing a major transformation in its presentation methods. Traditional static display methods are no longer able to meet audiences' growing demand for interactive experiences. In recent years, with the advancement of 3D scanning, virtual reality, and augmented reality technologies, digital display methods have gradually been applied to art exhibitions. However, current digital display technologies still have many shortcomings, mainly manifested in low digital acquisition accuracy of exhibits, poor material reproduction, and a subpar interactive experience.

[0003] Although there are existing solutions in the existing technology that use 3D scanning and virtual reality technology to display artworks, there are the following specific problems: First, the accuracy of the collected three-dimensional data of the exhibits is insufficient, making it difficult to restore the details of the exhibits, especially when dealing with artworks with complex textures and fine structures. The collection quality is difficult to guarantee; second, the material rendering effect is not realistic enough and cannot accurately present the texture of the artwork, resulting in a significant difference between the digital display effect and the real object; third, the perspective change response speed is slow and the system delay is large, which seriously affects the audience's immersive experience; fourth, the existing solutions generally lack in-depth analysis of the material characteristics of the exhibits, making it difficult to achieve a realistic reproduction of the artwork. Summary of the Invention

[0004] In view of the problems existing in the application of existing digital display technology in the field of art exhibitions, such as low acquisition accuracy, unrealistic material restoration, and poor interactive experience, the present invention is proposed.

[0005] Therefore, the problem to be solved by the present invention is how to achieve high-precision digital acquisition, realistic material rendering and smooth real-time interaction of art exhibits, so as to provide better digital display effects of artworks and audience experience.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0007] In a first aspect, an embodiment of the present invention provides a digital display method for art exhibitions, which includes scanning the surface of an exhibit with a depth camera to generate a point cloud data set; meshing the point cloud data set to generate a three-dimensional digital mesh of the exhibit; performing material feature analysis on the three-dimensional digital mesh of the exhibit to extract a material parameter set; collecting audience position coordinates, calculating the audience-exhibit relative azimuth based on the audience position coordinates, and generating a perspective transformation matrix; applying the perspective transformation matrix to the three-dimensional digital mesh of the exhibit, superimposing the material parameter set for rendering, outputting an exhibit image after perspective transformation, and synthesizing the exhibit image with the exhibition hall background image into a mixed reality scene; and dynamically updating the perspective transformation matrix based on real-time changes in the audience position coordinates to regenerate the mixed reality scene.

[0008] As a preferred solution of the digital display method for art exhibitions described in the present invention, the point cloud dataset includes the spatial position coordinates, surface reflection intensity values and normal vectors of multiple sampling points; the three-dimensional digital mesh of the exhibit includes a mesh vertex set, a topological connection matrix and a vertex normal vector set; and the material parameter set includes an ambient light coefficient, a diffuse reflection coefficient, a specular reflection coefficient and a texture mapping matrix.

[0009] As a preferred embodiment of the digital display method for art exhibitions described in the present invention, generating a point cloud dataset includes the following steps: arranging multiple depth cameras in an array with adjustable angles between the depth cameras to form an expandable annular scanning array; placing the annular scanning array on a lifting bracket, and driving the lifting bracket to move the annular scanning array in a vertical direction to form a spiral scanning trajectory; each depth camera emits infrared structured light, which is projected onto the surface of the exhibit to form a speckle pattern, and deformation characteristics of the speckle pattern are collected; based on the deformation characteristics of the speckle pattern, the spatial position coordinates of each sampling point on the exhibit surface are calculated; by analyzing the near-infrared light intensity received at each sampling point, the reflection intensity value of the exhibit surface is obtained; based on the spatial position relationship between adjacent sampling points, the normal vector of the surface on which each sampling point is located is fitted using the least squares method; and the spatial position coordinates of each sampling point, the reflection intensity value of the exhibit surface, and the normal vector are organized into structured data to generate a point cloud dataset.

[0010] As a preferred solution of the digital display method for art exhibitions described in the present invention, generating a three-dimensional digital grid of an exhibit includes the following steps: preprocessing a point cloud data set to remove noise points and performing spatial index encoding on the sampling points through octree spatial segmentation; setting a search radius with a leaf node of the octree as the center, extracting a local point set within the neighborhood of each leaf node, and calculating the covariance matrix of the local point set; performing eigenvalue decomposition on the covariance matrix to obtain a principal eigenvector, and using the principal eigenvector as an estimated value of the normal vector of the local surface; constructing an implicit function based on the distribution characteristics of the local point set, and obtaining the zero isosurface of the exhibit surface by solving the Poisson equation; uniformly sampling on the zero isosurface to generate a grid vertex set; using the Delaunay triangulation algorithm to connect the grid vertex set into a triangular grid and establish a topological connection matrix between the grid vertices; and calculating the vertex normal vector set for each vertex of the triangular grid based on the weighted average of the normal vectors of adjacent triangles.

[0011] As a preferred embodiment of the digital display method for art exhibitions described in the present invention, extracting a material parameter set includes the following steps: arranging a multi-light source array around the exhibit, the multi-light source array including light source units of different wavelengths, and generating structured lighting by controlling the switching sequence of each light source unit; collecting reflected light intensity images of the exhibit's three-dimensional digital grid under different lighting conditions, comparing the reflected light intensity images with the incident light intensity, and generating reflectivity data; spatially mapping the reflectivity data according to the grid vertex positions to construct a reflectivity distribution map, and segmenting the exhibit surface into material regions based on the reflectivity distribution map; for each material region, determining the ambient light coefficient by analyzing the reflectivity under dark lighting conditions; under diffuse light illumination conditions, analyzing the directional distribution of the reflected light intensity and calculating the diffuse reflection coefficient; using a high light illumination method, measuring the specular reflection peak and its attenuation law, and extracting the specular reflection coefficient; establishing a UV coordinate system based on the geometric characteristics of the exhibit surface, and generating a texture mapping matrix through minimum energy optimization.

[0012] As a preferred solution of the digital display method for art exhibitions described in the present invention, generating a perspective transformation matrix includes the following steps: arranging an infrared depth camera array on the top of the exhibition hall, the infrared depth camera array including multiple depth camera units, and the fields of view of each depth camera unit overlap with each other; acquiring a depth image through the infrared depth camera array, extracting the audience foreground target, and performing human key point detection on the foreground target; extracting the audience head feature points based on the detected human key points, and using the three-dimensional coordinates of the head feature points as the audience viewpoint position coordinates; establishing an exhibition hall world coordinate system, with the exhibit center point as the origin, and calculating the vector between the audience viewpoint position coordinates and the exhibit center point as the observation vector; decomposing the observation vector into a horizontal azimuth angle and a vertical pitch angle; constructing a rotation matrix based on the horizontal azimuth angle and the vertical pitch angle, and combining the rotation matrix with the translation matrix to generate a perspective transformation matrix between the audience and the exhibit.

[0013] As a preferred solution of the digital display method for art exhibitions described in the present invention, the process of generating a mixed reality scene is as follows: applying a perspective transformation matrix to the vertex set of the exhibit's three-dimensional digital grid, calculating the spatial position of the vertices after the perspective transformation, and generating a transformed grid geometry structure; based on the transformed grid geometry structure, constructing a depth buffer, determining the set of visible triangles on the grid surface, and removing occluded triangles; for each facet in the set of visible triangles, calculating a light transmission equation based on a material parameter set, wherein the ambient light coefficient, diffuse reflection coefficient, and specular reflection coefficient determine the shading effect of the facet; using a texture mapping matrix, projecting a texture image onto the visible triangles; collecting a real-time exhibition hall background image, extracting the exhibition hall's lighting parameters, and applying the lighting parameters to the exhibit image; and performing alpha blending on the rendered exhibit image and the exhibition hall background image to generate a mixed reality scene.

[0014] In a second aspect, an embodiment of the present invention provides a digital display system for art exhibitions, which includes a depth acquisition module for scanning the surface of an exhibit through a depth camera to generate a point cloud data set; a three-dimensional mesh reconstruction module for reconstructing the point cloud data set to generate a three-dimensional digital mesh of the exhibit; a material feature analysis module for performing material feature analysis on the three-dimensional digital mesh of the exhibit and extracting a material parameter set; an audience position tracking module for acquiring audience position coordinates, calculating the audience-exhibit relative azimuth based on the audience position coordinates, and generating a perspective transformation matrix; a mixed reality rendering module for applying the perspective transformation matrix to the three-dimensional digital mesh of the exhibit, superimposing the material parameter set for rendering, outputting an exhibit image after perspective transformation, and synthesizing the exhibit image with the exhibition hall background image into a mixed reality scene; and a dynamic scene update module for dynamically updating the perspective transformation matrix based on real-time changes in the audience position coordinates and regenerating the mixed reality scene.

[0015] The beneficial effects of this invention are as follows: Through the above-mentioned technical solution, this invention achieves high-precision digital acquisition, photorealistic rendering, and a smooth real-time interactive experience for art exhibits. Compared with existing technologies, this invention has the following advantages: First, the use of a multi-sensor collaborative acquisition solution significantly improves 3D reconstruction accuracy; second, the innovative introduction of multispectral structured light illumination technology enables precise acquisition of material properties; and third, the use of an improved visual tracking algorithm and real-time rendering optimization strategy controls system response latency below the human eye's perceptible threshold. Experimental results demonstrate that this invention can meet the application requirements of most art exhibition scenarios and has excellent practical value. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0017] Figure 1 A flowchart of a digital display method for art exhibitions;

[0018] Figure 2 Flowchart for generating a point cloud dataset for digital display methods of art exhibitions. DETAILED DESCRIPTION

[0019] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0020] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0021] Secondly, the term "one embodiment" or "embodiment" herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in various places throughout this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive of other embodiments.

[0022] Example 1, with reference to Figures 1 and 2 , which is the first embodiment of the present invention, provides a digital display method for art exhibitions, the flow chart is as follows Figure 1 Shown, including,

[0023] S1: Scan the surface of the exhibit with a depth camera to generate a point cloud dataset.

[0024] The point cloud dataset includes the spatial coordinates, surface reflection intensity, and normal vectors of multiple sampling points. By comprehensively considering these coordinates, reflection intensity, and normal vectors, the geometric form and surface features of the exhibits can be more comprehensively reconstructed.

[0025] Specifically, the point cloud dataset generation flow chart is as follows Figure 2 As shown, it specifically includes: arranging multiple depth cameras, the depth cameras are arranged in an array, and the angle between each depth camera is adjustable (120 degrees in this embodiment) to form an expandable annular scanning array. The selection of this angle is based on a large amount of experimental data, which minimizes data redundancy while ensuring scanning coverage; placing the annular scanning array on a lifting bracket, and driving the lifting bracket to move the annular scanning array in a vertical direction to form a spiral scanning trajectory. The moving speed of the lifting bracket is controlled within the range of 2-5mm / s, which is the optimal balance between scanning accuracy and efficiency.

[0026] Furthermore, each depth camera emits infrared structured light, which is projected onto the surface of the exhibit to form a speckle pattern, and the deformation characteristics of the speckle pattern are collected. The wavelength of the infrared light used is 850nm, which is the result of comprehensive consideration of the visual characteristics of the human eye and the sensitivity of the sensor. Based on the deformation characteristics of the speckle pattern, the spatial position coordinates of each sampling point on the exhibit surface are calculated using the principle of triangulation. By analyzing the intensity of the near-infrared light received at each sampling point, the reflection intensity value of the exhibit surface is obtained, and the reflection intensity value is used to characterize the material properties of the exhibit surface. Based on the spatial position relationship between adjacent sampling points, the least squares method is used to fit the normal vector of the surface where each sampling point is located. The normal vector is used to describe the orientation of the exhibit surface. The spatial position coordinates of each sampling point, the reflection intensity value of the exhibit surface and the normal vector are organized into structured data to generate a point cloud dataset.

[0027] To ensure accurate data collection, this invention uses an industry-leading depth camera with a depth resolution of up to 0.1mm, a field of view of 60 degrees, and a working distance range of 0.5 to 3 meters. These parameters were selected with full consideration of the size characteristics of the art exhibits and the requirements of the display environment.

[0028] Advantageously, compared to traditional single-view scanning methods, the multi-depth camera array scanning strategy of the present invention can significantly improve the integrity and accuracy of point cloud data. The circular array and spiral scanning trajectory can minimize data blind spots and enhance the ability to capture surface details of exhibits.

[0029] S2: Reconstruct the mesh of the point cloud dataset to generate a three-dimensional digital mesh of the exhibit.

[0030] Among them, the exhibited three-dimensional digital grid includes a grid vertex set, a topological connection matrix and a vertex normal vector set.

[0031] Specifically, the point cloud dataset is preprocessed, and the statistical outlier analysis method is used to remove noise points. Specifically, the average distance from each point to its nearest neighbor is calculated, and points that deviate from the mean by more than two standard deviations are identified as noise points. The sampling points are spatially indexed and encoded through octree spatial segmentation, where the depth of octree spatial segmentation can be dynamically adjusted according to the density and complexity of the point cloud dataset to balance computational efficiency and reconstruction accuracy. With the leaf node of the octree as the center, a search radius is set, which is three times the average point spacing. The local point set in the neighborhood of each leaf node is extracted, and the covariance matrix of the local point set is calculated.

[0032] Furthermore, the covariance matrix is subjected to eigenvalue decomposition to obtain the principal eigenvector, which is used as the estimated normal vector of the local surface. Based on the distribution characteristics of the local point set, an implicit function is constructed, and the zero isosurface of the exhibit surface is obtained by solving the Poisson equation. The zero isosurface is used to characterize the overall shape of the exhibit. When constructing the implicit function, methods such as radial basis functions (RBFs) or distance transfer functions (SDFs) can be used to improve the reconstruction ability of complex surface shapes. Uniform sampling is performed on the zero isosurface to generate a mesh vertex set containing the key feature points of the exhibit surface. The mesh vertex set is connected into a triangular mesh using the Delaunay triangulation algorithm, and a topological connection matrix between the mesh vertices is established. For each vertex in the triangular mesh, the vertex normal vector set is calculated based on the weighted average of the normal vectors of adjacent triangles. When calculating the vertex normal vector, a weight factor can be introduced to weight the vertex normal vector according to the angle between the normal vectors of adjacent triangles and the vertex normal vector and the area size to improve the accuracy of the normal vector estimation.

[0033] Advantageously, this step overcomes the limitations of traditional mesh reconstruction methods. Through innovative spatial indexing and surface reconstruction algorithms, it significantly improves the geometric accuracy and detail restoration of the exhibit's 3D digital mesh. Compared to traditional mesh reconstruction techniques, the method proposed in this paper is better able to handle complex curved surfaces and irregular geometries.

[0034] S3: Analyze the material characteristics of the exhibit’s three-dimensional digital grid and extract the material parameter set.

[0035] Among them, the material parameter set includes ambient light coefficient, diffuse reflection coefficient, specular reflection coefficient and texture mapping matrix.

[0036] Specifically, a multi-light source array is arranged around the exhibit. The multi-light source array includes light source units with different wavelengths. The light source wavelengths cover the visible spectrum (380-780nm) with an interval of 20nm. Structured lighting is generated by controlling the switching sequence of each light source unit. In order to reduce errors, the multi-light source array needs to be radiantly calibrated to ensure the consistency and repeatability of each light source unit. The reflected light intensity image of the three-dimensional digital grid of the exhibit under different lighting conditions is collected, and the reflected light intensity image is compared with the incident light intensity to generate reflectivity data. The reflectivity data is spatially mapped according to the grid vertex position to construct a reflectivity distribution map, and the material area of the exhibit surface is segmented based on the reflectivity distribution map.

[0037] Furthermore, for each material area, the ambient light coefficient is determined by analyzing the reflectivity under dark lighting conditions, and the ambient light coefficient is normalized to eliminate the scale differences between different material areas. The ambient light coefficient represents the material's ability to reflect ambient scattered light. Under diffuse light conditions, the directional distribution of the reflected light intensity is analyzed according to Lambert's cosine law, and the diffuse reflection coefficient is calculated. The diffuse reflection coefficient describes the scattering characteristics of the material. Using high-light illumination, the peak value of the specular reflection and its attenuation law are measured, and the specular reflection coefficient is extracted. The specular reflection coefficient represents the gloss of the material. Based on the geometric characteristics of the exhibit surface, a UV coordinate system is established, and the texture mapping matrix is generated through optimization using the minimum energy principle. The texture mapping matrix is used to project material details onto the three-dimensional grid surface.

[0038] Preferably, the material analysis method used in this step breaks through the limitations of traditional material measurement under a single light source, and achieves accurate acquisition of material characteristics through multi-spectral structured light illumination. Experiments have shown that this method can accurately restore more than 90% of common artwork materials, including metals, ceramics, fabrics, etc.

[0039] S4: Collect the audience's position coordinates, calculate the audience-exhibit relative azimuth based on the audience's position coordinates, and generate a perspective transformation matrix.

[0040] Specifically, an infrared depth camera array is arranged on the top of the exhibition hall. The infrared depth camera array includes multiple depth camera units. The field of view of each depth camera unit overlaps with each other, and the overlapping area of adjacent cameras is not less than 30% to ensure seamless tracking effect. The depth image is obtained through the infrared depth camera array, and the background difference method is used to extract the audience foreground target. The human key point detection is performed on the foreground target. The improved OpenPose algorithm is used for human posture estimation, and the key point detection accuracy rate reaches more than 95%. Based on the detected human key points, the audience's head feature points are extracted, and the three-dimensional coordinates of the head feature points are used as the audience's viewpoint position coordinates.

[0041] Furthermore, a world coordinate system for the exhibition hall is established, with the center point of the exhibit as the origin, and the vector between the viewer's viewpoint position coordinates and the exhibit center point is calculated as the observation vector; based on the world coordinate system of the exhibition hall and the coordinates of the viewer's head, the relative translation vector is calculated to form a translation matrix; the observation vector is decomposed into a horizontal azimuth and a vertical pitch angle, where the horizontal azimuth represents the viewer's viewing direction in the horizontal plane, and the vertical pitch angle represents the degree to which the viewer is looking up or down; based on the horizontal azimuth and vertical pitch angle, a rotation matrix is constructed, and the rotation matrix is combined with the translation matrix to generate a perspective transformation matrix between the viewer and the exhibit; the perspective transformation matrix is calibrated to eliminate the coordinate system conversion error and ensure the accuracy of the perspective conversion.

[0042] S5: Apply the perspective transformation matrix to the three-dimensional digital grid of the exhibit, superimpose the material parameter set for rendering, output the exhibit image after the perspective transformation, and synthesize the exhibit image with the exhibition hall background image into a mixed reality scene.

[0043] Specifically, the perspective transformation matrix is applied to the vertex set of the exhibit's three-dimensional digital grid, the spatial position of the vertices after the perspective transformation is calculated, and the transformed grid geometry structure is generated; based on the transformed grid geometry structure, a depth buffer is constructed, and the Z-buffer algorithm is used to determine the set of visible triangles on the grid surface, and the occluded triangles are removed; for each facet in the visible triangle set, the light transmission equation is calculated according to the material parameter set, where the ambient light coefficient, diffuse reflection coefficient, and specular reflection coefficient determine the shading effect of the facet.

[0044] Furthermore, the texture mapping matrix is used to project the high-resolution texture image onto the visible triangular facets, and a smooth texture transition effect is generated through a bilinear interpolation algorithm; the real-time background image of the exhibition hall is collected, the lighting parameters of the exhibition hall are extracted, and the lighting parameters are applied to the exhibit rendering process, so that the exhibits present a lighting effect consistent with the exhibition hall environment; the rendered exhibit image is anti-aliased, the edge pixels are smoothed, and the image display quality is improved; the processed exhibit image is Alpha blended with the exhibition hall background image to generate a realistic mixed reality scene.

[0045] S6: Based on the real-time changes in the viewer's position coordinates, the perspective transformation matrix is dynamically updated to regenerate the mixed reality scene.

[0046] Specifically, audience motion data is collected at a frequency of 30 frames per second through a depth camera array, the motion trajectory of the audience's head feature points is extracted, and a sequence of audience position coordinates is generated; Kalman filtering is performed on the audience position coordinate sequence to eliminate position coordinate jitter and predict the audience position coordinates at the next moment. The process noise covariance and observation noise covariance of the Kalman filter are obtained through experimental optimization, which can effectively suppress more than 90% of tracking jitter; based on the filtered audience position coordinates, the quaternion interpolation method is used to calculate the gradual process of the perspective transformation matrix to achieve a smooth transition of perspective; the updated perspective transformation matrix is passed to the graphics processing unit, and the parallel transformation calculation of the mesh vertices is started to accelerate the geometric transformation processing; the material parameter set is kept unchanged, and material rendering is performed on the transformed mesh, and the inter-frame difference technology is used to update only the changed image area; the dynamic changes of the exhibition hall background image are detected, and the background update is synchronized with the exhibit rendering results to maintain the temporal consistency of the mixed reality scene; the generated mixed reality scene is output in real time through the display device to ensure that the image refresh delay is less than 16 milliseconds.

[0047] Furthermore, this embodiment also provides a digital display system for art exhibitions, including a depth acquisition module for scanning the surface of the exhibit through a depth camera to generate a point cloud data set; a three-dimensional mesh reconstruction module for reconstructing the point cloud data set to generate a three-dimensional digital mesh of the exhibit; a material feature analysis module for performing material feature analysis on the three-dimensional digital mesh of the exhibit and extracting a material parameter set; an audience position tracking module for acquiring audience position coordinates, calculating the audience-exhibit relative azimuth based on the audience position coordinates, and generating a perspective transformation matrix; a mixed reality rendering module for applying the perspective transformation matrix to the three-dimensional digital mesh of the exhibit, superimposing the material parameter set for rendering, outputting the exhibit image after perspective transformation, and synthesizing the exhibit image with the exhibition hall background image into a mixed reality scene; and a dynamic scene update module for dynamically updating the perspective transformation matrix based on real-time changes in the audience position coordinates and regenerating the mixed reality scene.

[0048] In summary, the present invention, through the aforementioned technical solutions, achieves high-precision digital acquisition, photorealistic rendering, and a smooth real-time interactive experience for art exhibits. Compared to existing technologies, it offers the following advantages: First, a multi-sensor collaborative acquisition solution significantly improves 3D reconstruction accuracy; second, the innovative introduction of multispectral structured light illumination technology enables precise acquisition of material properties; and third, an improved visual tracking algorithm and real-time rendering optimization strategy are employed to control system response latency below the human eye's perceptible threshold. Experimental results demonstrate that the present invention can meet the application requirements of most art exhibition scenarios and possesses excellent practical value.

[0049] Example 2, reference Figures 1 and 2, which is the second embodiment of the present invention, provides a digital display method for art exhibitions. In order to verify the beneficial effects of the present invention, scientific demonstration is carried out through economic benefit calculation and simulation experiments.

[0050] To verify the feasibility and performance of this digital display method, the research team conducted three months of system testing and experiments at an art museum. The testing site was an 80-square-meter dedicated exhibition hall, and 10 artworks made of various materials, including bronze, porcelain, and textiles, were selected as test objects.

[0051] During the point cloud data collection phase, six Intel RealSense D455 depth cameras were used in a circular scanning array, with the cameras angled at 120 degrees. The lifting bracket's movement speed was set at 3mm / s, and a complete scan of a single exhibit took approximately 15 minutes. Experimental data showed that, under 850nm wavelength infrared structured light illumination, the average sampling point density reached 0.2mm / point for exhibits measuring 50cm×50cm×50cm, and the spatial accuracy of the point cloud data was better than 0.1mm.

[0052] During mesh reconstruction, octree spatial segmentation was used to divide sampling points into voxel units of 2mm×2mm×2mm, with a search radius of 6mm. Experiments demonstrated that this parameter setting effectively balanced reconstruction accuracy and computational efficiency, achieving a noise point rejection rate of 98.5%. The average side length of the reconstructed triangular mesh was 0.5mm, accurately reproducing over 95% of the geometric details of the exhibit surface.

[0053] Material characterization analysis utilizes 20 LED light sources with different wavelengths, ranging from 380 to 780 nm, with 20 nm intervals. A controller generates 2048 different lighting combinations to acquire reflectance data. Experimental results demonstrate that this method can accurately identify and quantify the optical properties of seven common artwork materials, with measurement errors within 5%.

[0054] In the visitor tracking experiment, eight infrared depth cameras were deployed at the exhibition hall's ceiling, creating an overlapping field of view. Adjacent cameras overlapped by 35%. Using an improved OpenPose algorithm for human pose estimation, tests were conducted under varying lighting conditions and crowd density. The accuracy of head feature point detection reached 96.8%, with an average position error of less than 1 cm. Applying a Kalman filter reduced tracking jitter by 92.3%, increasing prediction accuracy to 98.2%.

[0055] In real-time rendering tests, using an NVIDIA RTX 3080 graphics card for graphics processing, the average processing time for perspective transformation and material rendering for an exhibit model containing 500,000 triangles was 12ms, and the background synthesis time was 3ms. Overall system latency was kept within 16ms, ensuring a smooth interactive experience. During a week-long public test, over 3,000 visitors experienced the system, and satisfaction surveys showed that 93.5% of visitors believed the system provided a near-realistic viewing experience.

[0056] In order to systematically evaluate the advantages of the method of the present invention, the research team conducted detailed comparative experiments with the existing technology. The results are shown in Table 1.

[0057] Table 1 Performance comparison between the present invention and the prior art

[0058] Performance indicators Method of the present invention Traditional single-view scanning method <![CDATA[Point cloud density (points / mm 2 )]]> 25 10 Geometric accuracy (mm) 0.1 0.3 Material recognition accuracy (%) 95 70 Viewing angle response time (ms) 16 50 Scene update frame rate (fps) 60 20

[0059] The comparative data in Table 1 demonstrates that the proposed method significantly outperforms existing technologies across all key performance indicators, with particularly significant improvements in point cloud density, geometric accuracy, and material recognition accuracy. These advantages, primarily due to the innovative multi-view scanning strategy and high-precision material analysis methods, provide enhanced technical support for the digital display of art exhibitions.

[0060] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A digital display method for art exhibitions, characterized in that: include, Scan the surface of the exhibits with a depth camera to generate a point cloud dataset; Reconstructing the point cloud data set to generate a three-dimensional digital grid of the exhibit; Performing material feature analysis on the three-dimensional digital grid of the exhibit to extract a material parameter set; Collecting the audience position coordinates, calculating the audience-exhibit relative azimuth based on the audience position coordinates, and generating a perspective transformation matrix; Applying the perspective transformation matrix to the three-dimensional digital grid of the exhibit, superimposing the material parameter set for rendering, outputting an image of the exhibit after perspective transformation, and synthesizing the exhibit image with the exhibition hall background image into a mixed reality scene; Based on the real-time changes in the viewer's position coordinates, dynamically updating the perspective transformation matrix to regenerate the mixed reality scene; Extracting the material parameter set includes the following steps: Arrange a multi-light source array around the exhibit, wherein the multi-light source array includes light source units of different wavelengths, and generate structured lighting by controlling the on / off sequence of each light source unit; collecting reflected light intensity images of the three-dimensional digital grid of the exhibit under different lighting conditions, comparing the reflected light intensity images with the incident light intensity, and generating reflectivity data; Performing spatial mapping on the reflectivity data according to grid vertex positions to construct a reflectivity distribution map, and performing material area segmentation on the exhibit surface based on the reflectivity distribution map; For each material area, the ambient light coefficient is determined by analyzing the reflectivity under dark lighting conditions; Under diffuse light illumination conditions, the directional distribution of reflected light intensity is analyzed and the diffuse reflectance is calculated; Using high light illumination, measure the specular reflection peak and its attenuation law, and extract the specular reflection coefficient; Based on the geometric features of the exhibit surface, a UV coordinate system is established, and the texture mapping matrix is generated through optimization using the minimum energy principle.

2. The digital display method for art exhibition according to claim 1, characterized in that: The point cloud data set includes spatial position coordinates, surface reflection intensity values and normal vectors of multiple sampling points; The three-dimensional digital mesh of the exhibit includes a mesh vertex set, a topological connection matrix and a vertex normal vector set; The material parameter set includes an ambient light coefficient, a diffuse reflection coefficient, a specular reflection coefficient, and a texture mapping matrix.

3. The digital display method for art exhibition according to claim 1, characterized in that: Generating a point cloud dataset comprises the following steps: Arrange multiple depth cameras, wherein the depth cameras are arranged in an array, and the angles between the depth cameras are adjustable to form an expandable annular scanning array; Placing the annular scanning array on a lifting bracket, and driving the annular scanning array to move in a vertical direction by the lifting bracket to form a spiral scanning trajectory; Each depth camera emits infrared structured light, projects it onto the surface of the exhibit to form a speckle pattern, and collects deformation features of the speckle pattern; Calculating the spatial position coordinates of each sampling point on the surface of the exhibit according to the deformation characteristics of the speckle pattern; By analyzing the near-infrared light intensity received at each sampling point, the reflection intensity value of the exhibit surface is obtained; Based on the spatial position relationship of adjacent sampling points, the least squares method is used to fit the normal vector of the surface where each sampling point is located; The spatial position coordinates of each sampling point, the reflection intensity value of the exhibit surface and the normal vector are organized into structured data to generate a point cloud dataset.

4. The digital display method for art exhibition according to claim 1, characterized in that: Generating the three-dimensional digital grid of the exhibits comprises the following steps: Preprocess the point cloud dataset, remove noise points, and perform spatial index encoding on the sampling points through octree spatial segmentation; Taking the leaf node of the octree as the center, setting the search radius, extracting the local point set within the neighborhood of each leaf node, and calculating the covariance matrix of the local point set; Performing eigenvalue decomposition on the covariance matrix to obtain a principal eigenvector, and using the principal eigenvector as an estimated value of a normal vector of a local surface; Based on the distribution characteristics of the local point set, an implicit function is constructed and the zero isosurface of the exhibit surface is obtained by solving the Poisson equation. uniformly sampling on the zero isosurface to generate a mesh vertex set; Using a Delaunay triangulation algorithm, the mesh vertex set is connected into a triangular mesh, and a topological connection matrix between the mesh vertices is established; For each vertex of the triangular mesh, a vertex normal vector set is calculated based on a weighted average of normal vectors of adjacent triangular facets.

5. The digital display method for art exhibition according to claim 1, characterized in that: Generating the perspective transformation matrix comprises the following steps: Arrange an infrared depth camera array on the top of the exhibition hall, wherein the infrared depth camera array includes multiple depth camera units, and the fields of view of each depth camera unit overlap with each other; Acquire a depth image through the infrared depth camera array, extract the audience foreground target, and perform human key point detection on the foreground target; Extracting the audience's head feature points based on the detected human body key points, and using the three-dimensional coordinates of the head feature points as the audience's viewpoint position coordinates; Establish the exhibition hall's world coordinate system, take the exhibit center as the origin, and calculate the vector between the viewer's viewpoint position coordinates and the exhibit center as the observation vector; Decomposing the observation vector into a horizontal azimuth angle and a vertical pitch angle; A rotation matrix is constructed according to the horizontal azimuth angle and the vertical pitch angle, and the rotation matrix is combined with the translation matrix to generate a viewpoint transformation matrix between the audience and the exhibit.

6. The digital display method for art exhibition according to claim 1, characterized in that: The generation process of the mixed reality scene is as follows: Apply the perspective transformation matrix to the vertex set of the exhibit's three-dimensional digital grid, calculate the spatial position of the vertices after the perspective transformation, and generate the transformed grid geometry structure; Based on the transformed mesh geometry, a depth buffer is constructed to determine the set of visible triangles on the mesh surface and remove obscured triangles. For each face in the visible triangle set, the light transmission equation is calculated according to the material parameter set, where the ambient light coefficient, diffuse reflection coefficient and specular reflection coefficient determine the shading effect of the face; Use the texture mapping matrix to project the texture image onto the visible triangles; Collecting real-time exhibition hall background images, extracting the exhibition hall's lighting parameters, and applying the lighting parameters to the exhibit images; Alpha blending is performed on the rendered exhibit image and the exhibition hall background image to generate a mixed reality scene.

7. A digital display system for art exhibitions, characterized in that: The system includes: Depth acquisition module, used to scan the surface of exhibits through a depth camera to generate a point cloud dataset; A three-dimensional mesh reconstruction module is used to reconstruct the mesh of the point cloud data set to generate a three-dimensional digital mesh of the exhibit; A material feature analysis module, configured to perform material feature analysis on the three-dimensional digital grid of the exhibit and extract a material parameter set; The audience position tracking module is used to collect audience position coordinates, calculate the relative azimuth angle between the audience and the exhibit based on the audience position coordinates, and generate a perspective transformation matrix; a mixed reality rendering module, configured to apply the perspective transformation matrix to the three-dimensional digital grid of the exhibit, superimpose the material parameter set for rendering, output an image of the exhibit after the perspective transformation, and synthesize the exhibit image with the exhibition hall background image into a mixed reality scene; A dynamic scene update module, configured to dynamically update the view transformation matrix based on real-time changes in the viewer's position coordinates, and regenerate a mixed reality scene; Extracting the material parameter set includes the following steps: Arrange a multi-light source array around the exhibit, wherein the multi-light source array includes light source units of different wavelengths, and generate structured lighting by controlling the on / off sequence of each light source unit; collecting reflected light intensity images of the three-dimensional digital grid of the exhibit under different lighting conditions, comparing the reflected light intensity images with the incident light intensity, and generating reflectivity data; Performing spatial mapping on the reflectivity data according to grid vertex positions to construct a reflectivity distribution map, and performing material area segmentation on the exhibit surface based on the reflectivity distribution map; For each material area, the ambient light coefficient is determined by analyzing the reflectivity under dark lighting conditions; Under diffuse light illumination conditions, the directional distribution of reflected light intensity is analyzed and the diffuse reflectance is calculated; Using high light illumination, measure the specular reflection peak and its attenuation law, and extract the specular reflection coefficient; Based on the geometric features of the exhibit surface, a UV coordinate system is established, and the texture mapping matrix is generated through optimization using the minimum energy principle.

8. The digital display system for art exhibition according to claim 7, characterized in that: The point cloud data set includes spatial position coordinates, surface reflection intensity values and normal vectors of multiple sampling points; The three-dimensional digital mesh of the exhibit includes a mesh vertex set, a topological connection matrix and a vertex normal vector set; The material parameter set includes an ambient light coefficient, a diffuse reflection coefficient, a specular reflection coefficient, and a texture mapping matrix.

9. The digital display system for art exhibition according to claim 7, characterized in that: Generating a point cloud dataset comprises the following steps: Arrange multiple depth cameras, wherein the depth cameras are arranged in an array, and the angles between the depth cameras are adjustable to form an expandable annular scanning array; Placing the annular scanning array on a lifting bracket, and driving the annular scanning array to move in a vertical direction by the lifting bracket to form a spiral scanning trajectory; Each depth camera emits infrared structured light, projects it onto the surface of the exhibit to form a speckle pattern, and collects deformation features of the speckle pattern; Calculating the spatial position coordinates of each sampling point on the surface of the exhibit according to the deformation characteristics of the speckle pattern; By analyzing the near-infrared light intensity received at each sampling point, the reflection intensity value of the exhibit surface is obtained; Based on the spatial position relationship of adjacent sampling points, the least squares method is used to fit the normal vector of the surface where each sampling point is located; The spatial position coordinates of each sampling point, the reflection intensity value of the exhibit surface and the normal vector are organized into structured data to generate a point cloud dataset.

10. The digital display system for art exhibition according to claim 7, wherein: Generating the three-dimensional digital grid of the exhibits comprises the following steps: Preprocess the point cloud dataset, remove noise points, and perform spatial index encoding on the sampling points through octree spatial segmentation; Taking the leaf node of the octree as the center, setting the search radius, extracting the local point set within the neighborhood of each leaf node, and calculating the covariance matrix of the local point set; Performing eigenvalue decomposition on the covariance matrix to obtain a principal eigenvector, and using the principal eigenvector as an estimated value of a normal vector of a local surface; Based on the distribution characteristics of the local point set, an implicit function is constructed and the zero isosurface of the exhibit surface is obtained by solving the Poisson equation. uniformly sampling on the zero isosurface to generate a mesh vertex set; Using a Delaunay triangulation algorithm, the mesh vertex set is connected into a triangular mesh, and a topological connection matrix between the mesh vertices is established; For each vertex of the triangular mesh, a vertex normal vector set is calculated based on a weighted average of normal vectors of adjacent triangular facets.

11. The digital display system for art exhibition according to claim 7, characterized in that: Generating the perspective transformation matrix comprises the following steps: Arrange an infrared depth camera array on the top of the exhibition hall, wherein the infrared depth camera array includes multiple depth camera units, and the fields of view of each depth camera unit overlap with each other; Acquire a depth image through the infrared depth camera array, extract the audience foreground target, and perform human key point detection on the foreground target; Extracting the audience's head feature points based on the detected human body key points, and using the three-dimensional coordinates of the head feature points as the audience's viewpoint position coordinates; Establish the exhibition hall's world coordinate system, take the exhibit center as the origin, and calculate the vector between the viewer's viewpoint position coordinates and the exhibit center as the observation vector; Decomposing the observation vector into a horizontal azimuth angle and a vertical pitch angle; A rotation matrix is constructed according to the horizontal azimuth angle and the vertical pitch angle, and the rotation matrix is combined with the translation matrix to generate a viewpoint transformation matrix between the audience and the exhibit.

12. The digital display system for art exhibition according to claim 7, wherein: The generation process of the mixed reality scene is as follows: Apply the perspective transformation matrix to the vertex set of the exhibit's three-dimensional digital grid, calculate the spatial position of the vertices after the perspective transformation, and generate the transformed grid geometry structure; Based on the transformed mesh geometry, a depth buffer is constructed to determine the set of visible triangles on the mesh surface and remove obscured triangles. For each face in the visible triangle set, the light transmission equation is calculated according to the material parameter set, where the ambient light coefficient, diffuse reflection coefficient and specular reflection coefficient determine the shading effect of the face; Use the texture mapping matrix to project the texture image onto the visible triangles; Collecting real-time exhibition hall background images, extracting the exhibition hall's lighting parameters, and applying the lighting parameters to the exhibit images; Alpha blending is performed on the rendered exhibit image and the exhibition hall background image to generate a mixed reality scene.

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