A comparative analysis method for relative positions of cultural relics dismantled and restored using real-life three-dimensional models

Abstract

The present invention discloses a comparative analysis method for the relative position of the dismantling and restoration of cultural relics using a real-scene three-dimensional model. First, the individual components of the cultural relics to be dismantled are marked with two-dimensional codes respectively, and then the real-scene three-dimensional information is collected and a real-scene three-dimensional model containing the two-dimensional code information is established; then the spatial coordinates of the real-scene three-dimensional model and its two-dimensional code information are identified and registered; finally, the restored cultural relics are photographed to obtain a photographic image, and a projection image is obtained by adjusting the virtual camera of the real-scene three-dimensional model to the same viewing angle; and the restoration effect is determined by comparing the coordinate difference between the photographic image after the dismantling and restoration of the cultural relics and the corresponding two-dimensional code basic points of the projection image. The technical solution of the present invention is used to realize the automated analysis of the restoration of cultural relics, avoiding a large amount of measurement work.

Description

Technical Field

[0001] The present invention relates to the technical field of real-scene three-dimensional modeling, and in particular to a method for comparative analysis of relative positions of cultural relics disassembled and restored using a real-scene three-dimensional model. Background Art

[0002] In order to strengthen the protection of cultural relics, under certain circumstances, cultural relics need to be disassembled and then reassembled in a suitable environment for restoration. In the past, the restoration effect mainly relied on visual inspection or measurement comparison, which was a huge workload and prone to errors. In addition, the accuracy of manual inspection mainly depended on the experience and carefulness of the personnel.

[0003] High-precision real-life 3D models usually refer to 3D digital models with high geometric accuracy and real texture features of target objects constructed using ground 3D laser scanning equipment, high-pixel cameras and related modeling software. With the help of high-precision 3D laser scanning equipment, high-precision point cloud data is collected on the surface of the target object, and then the 3D model of the scanned target is constructed using modeling software. The geometric accuracy of the model depends on the scanning equipment and its distance from the scanned object. Through close-range scanning (such as less than 4 meters), a scanning result with an absolute geometric accuracy error of less than 0.4mm can be obtained, and the relative geometric accuracy error is close to 0. In terms of the realistic texture of the model, the target object is photographed from multiple angles with a high-pixel digital camera to collect the ultra-high pixel texture features of the cultural relics, and then post-processed and merged with the above-mentioned high precision to form a high-precision real-life 3D model. The high-precision real-life 3D model has the characteristics of high fidelity, and almost perfectly retains the appearance and geometric structure features of the cultural relics. With the help of immersive 3D display devices such as VR, it can produce a visual effect that is almost consistent with watching actual cultural relics and relics. At present, the present invention has been widely used as an advanced means of digital protection of cultural relics and relics.

[0004] QR code technology is widely used for information tag storage, which is convenient for recognition by scanning devices such as cameras. It can easily identify the posture angle of the QR code and the information stored in the QR code. It is a mature technology that is currently widely used.

[0005] The existing analysis of the disassembly and restoration effects of cultural relics mainly relies on manual inspection, including visual inspection and the use of various surveying and mapping instruments to measure and compare factors such as the relative position and posture of each module of the restored object. This is time-consuming and labor-intensive, and lacks a more convenient high-precision analysis method. Summary of the invention

[0006] In order to solve the above problems, the present invention provides a comparative analysis method for the relative positions of disassembled and restored cultural relics using a real-scene three-dimensional model, which realizes automatic analysis of the restoration effect of cultural relics and improves the reliability of the analysis.

[0007] In order to achieve the above object, the present invention adopts the following technical scheme:

[0008] A comparative analysis method for relative positions of cultural relics dismantled and restored using a real-scene three-dimensional model comprises the following steps:

[0009] Step S100: firstly, the individual components of the cultural relics to be disassembled are marked with QR codes respectively, and then the real scene three-dimensional information is collected and a real scene three-dimensional model including the QR code information is established;

[0010] Step S200: Identify and register the spatial coordinates of the real-scene 3D model and its QR code information;

[0011] Step S300: photograph the restored cultural relics to obtain a photographic image, and obtain a projection image by adjusting the virtual camera of the real-scene 3D model to the same viewing angle; determine the restoration effect by comparing the coordinate difference between the basic points of the QR code corresponding to the photographic image and the projection image after the cultural relics are disassembled and restored.

[0012] In the above-mentioned method for comparing and analyzing the relative positions of the dismantling and restoration of cultural relics using real-life three-dimensional models, in step S100: the cultural relics to be dismantled containing the QR code are scanned by a ground-based three-dimensional laser scanner to collect a three-dimensional laser point cloud; photos are taken by a data camera to collect texture information of the cultural relics to be dismantled; and a real-life three-dimensional model of the cultural relics to be dismantled containing the QR code information is constructed by modeling software.

[0013] In the above-mentioned relative position comparison and analysis method for disassembling and restoring cultural relics using a real-life three-dimensional model, the two-dimensional code information includes the spatial coordinates and relative order of each basic point of the two-dimensional code.

[0014] In the above-mentioned method for comparative analysis of relative positions of cultural relics dismantled and restored using a real-scene three-dimensional model, step S300 includes the following steps:

[0015] Step S310: collecting photographic images of all restored cultural relics marked with QR codes;

[0016] Step S320: Identify and register the spatial coordinates of the real-scene 3D model and its QR code information based on the restored photographic image of the cultural relic;

[0017] Step S330: obtaining a projection image that matches the restored photographic image of the cultural relic;

[0018] Step S340: comparative analysis of restoration effects based on image comparison;

[0019] Step S350: List the QR codes with problems in the comparison and analysis results to facilitate staff review.

[0020] In the above-mentioned method for comparative analysis of relative positions of cultural relics dismantled and restored using a real-scene three-dimensional model, step S320 includes the following steps:

[0021] Step S321: using the restored cultural relic photographic image acquired in step S310, identifying the QR code information on the restored cultural relic photographic image.

[0022] Step S322: Select a QR code on the restored cultural relic photographed image, query and find the QR code on the real-life 3D model in the virtual scene corresponding to the QR code.

[0023] Step S323: Based on the correspondence between the basic points on the two QR codes of the photographed image in step S322, the camera pose matrix is ​​solved to complete the tracking and registration of all restored cultural relic QR codes to the real-scene 3D model QR codes in the virtual scene.

[0024] In the above-mentioned method for comparative analysis of relative positions of cultural relics dismantled and restored using a real-scene three-dimensional model, step S340 includes the following steps:

[0025] Step S341: establishing a correspondence between basic points in the QR code in the photographed image and the projected image through QR code image recognition.

[0026] Step S342: Take the first basic point of the scene registration QR code in step S330 as the image origin and establish a photographed image coordinate system in pixels; take the coordinate point in the projected image corresponding to the first basic point of the QR code as the image origin and establish a projected image coordinate system in pixels; finally, merge the photographed image coordinate system and the projected image coordinate system into one image coordinate system.

[0027] Step S343: In the image coordinate system, the image coordinates of the corresponding points in the photographed image and the projected image are compared. If the coordinate difference between the corresponding points is less than a threshold, it is considered that the restoration effect is good.

[0028] In the above-mentioned method for comparative analysis of relative positions of disassembled and restored cultural relics using real-life three-dimensional models, step S340 can also be replaced by the following steps: by using the inverse transformation of the projection matrix to calculate the corresponding points on the real-life three-dimensional model from the basic points of the QR code in the photographed image of the restored cultural relics, and then further analyzing the spatial deviation between the corresponding points and the basic points of the QR code on the real-life three-dimensional model, thereby achieving comparative analysis of the restoration effect.

[0029] The beneficial effects of the present invention are:

[0030] 1. The present invention combines AR technology, high-precision real-scene 3D modeling technology, QR code recognition technology, and intelligent terminals to establish a complete set of portable automatic analysis methods for the disassembly and restoration effects of cultural relics;

[0031] 2. In actual operation, the present invention can realize automatic analysis of the restoration of cultural relics by taking pictures, thus avoiding a large amount of measurement work;

[0032] 3. The present invention can be used for real-time inspection in the restoration process of cultural relics after they are dismantled. By taking real-time photos and analyzing the restoration situation, unsatisfactory restoration results and damage and losses caused by repeated dismantling of cultural relics can be avoided. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0034] In order to solve the problem of efficient and accurate inspection of restoration effects, the present invention embeds a high-precision real-scene three-dimensional model containing the two-dimensional code marks of each block of the original cultural relic into an analysis application on a mobile terminal such as a mobile phone or tablet computer, so that the restored cultural relic can be scanned by aiming the mobile phone camera at it, and the analysis results of the restoration effect can be automatically output, thereby assisting the scientific implementation of the disassembly and restoration inspection of the cultural relics.

[0035] The implementation steps of the present invention are as follows:

[0036] Step S100: Collecting the QR code marks of the cultural relics and the high-precision real-scene 3D model.

[0037] Step S110: Use QR codes to mark the blocks of cultural relics before disassembling them. Before disassembling the cultural relics, they are numbered according to their natural blocks, and the numbering information is converted into a QR code, which is then made into a QR code nameplate and attached to the surface of the corresponding cultural relic block.

[0038] Step S120: Establish a high-precision real-scene 3D model of the cultural relic including the QR code. Use high-precision ground 3D laser scanning equipment to scan the cultural relic to be disassembled with the QR code name tag at close range, collect its high-precision 3D laser point cloud, then use a high-pixel data camera to take pictures around the cultural relic to collect texture information, and finally use CC and other modeling software to automatically build a high-precision real-scene 3D model of the cultural relic including the QR code identification information.

[0039] Step S200: Use the mobile APP to identify and register the model QR code.

[0040] Step S210: Importing the high-precision real-scene 3D model of the cultural relic containing the QR code. Using the scene import function of a mobile terminal such as a mobile phone or a tablet computer, the high-precision real-scene 3D model of the cultural relic containing the QR code information is imported into a mobile terminal such as a mobile phone or a tablet computer.

[0041] Step S220: QR code feature recognition and database building. Rotate the model and traverse all QR codes on the model. The system automatically recognizes all QR codes in the model based on the built-in mature QR code recognition algorithm, and automatically collects the spatial coordinates and relative order of each basic point of the QR code. These spatial coordinates will be saved in the mobile terminal database together with the information stored in the QR code.

[0042] Step S300: Use the mobile APP to analyze the effect of dismantling and restoring cultural relics

[0043] Step S310: Collecting photographic images of restored cultural relics covering all QR code labels.

[0044] Use the camera of a smart mobile terminal such as a mobile phone or tablet computer to aim at the restored cultural relics and take multiple photos around the restored cultural relics. The QR code images on these photos must be clear and these photos must cover all QR codes on the restored cultural relics.

[0045] Step S320: registering the three-dimensional scene based on the restored cultural relic photographic image, including the following steps:

[0046] Step S321: Using the restored cultural relic photographic image collected in step S310, the system automatically identifies the QR code information on the restored cultural relic photographic image and its three basic points and relative order based on a mature QR code recognition algorithm.

[0047] Step S322: Select a QR code on the restored cultural relic image that is closest to the field of view of the mobile phone camera and closest to the orthophoto scan, and find the QR code on the virtual reality 3D model corresponding to the QR code through database query.

[0048] Step S323: Based on the correspondence between the three pairs of basic points on the two virtual and real QR codes, the camera pose matrix is ​​solved to complete the tracking and registration of the restored cultural relic QR code to the real scene 3D model QR code in the virtual scene.

[0049] Step S330: Obtain a projection image that matches the photographic image of the restored cultural relic. In step S320, the registration of the three-dimensional scene has been achieved, and it can be considered that the spatial position of the restored cultural relic in the photographic image of the restored cultural relic obtained by taking pictures in the camera coordinate system of a mobile terminal such as a mobile phone or a tablet computer is consistent with the spatial position of the high-precision real-life three-dimensional model of the cultural relic in the virtual scene in the camera coordinate system of the virtual scene. Therefore, the viewing angle of the virtual camera is adjusted to be consistent with the real camera, and a projection image of the high-precision real-life three-dimensional model in the virtual scene is obtained as an image that matches the photographic image of the restored cultural relic obtained by actually taking pictures in step S310.

[0050] Step S340: comparative analysis of restoration effects based on image comparison, including the following steps:

[0051] Step S341: The photographed image and the projected image both contain a number of two-dimensional code images (the number should be no less than 2). Through two-dimensional code image recognition, a correspondence relationship between basic points in the two-dimensional codes in the two images is established.

[0052] Step S342: Take the first basic point of the QR code used for scene registration in step S330 as the image origin (the coordinate point corresponding to this point in the projected image is the image origin), and establish an image coordinate system in pixels to obtain the image coordinates of each basic point of the QR code in the two images.

[0053] Step S343: Compare the image coordinates of the corresponding points in the two images. If the coordinate difference between the corresponding points is less than a threshold, it is considered that the restoration effect is good.

[0054] Step S350: Automatically analyze the restoration effects of all restored cultural relics photographic images, and automatically list the problematic identification codes to facilitate staff review.

[0055] In step S340, the actual photographed image of the restored cultural relic is compared and analyzed with the projected image of the virtual scene. The corresponding points on the model can be solved by the inverse transformation of the projection matrix for the two-dimensional code basic points in the actual photographed image of the restored cultural relic, and the spatial deviation between these points and the two-dimensional code basic points on the model texture is further analyzed, so as to achieve comparative analysis of the restoration effect.

[0056] 1. The present invention combines AR technology, high-precision real-scene 3D modeling technology, QR code recognition technology, and intelligent terminals to establish a complete set of portable automatic analysis methods for the disassembly and restoration effects of cultural relics;

[0057] 2. In actual operation, the present invention can realize automatic analysis of the restoration of cultural relics by taking pictures, thus avoiding a large amount of measurement work;

[0058] 3. The present invention can be used for real-time inspection in the restoration process of cultural relics after they are dismantled. By taking real-time photos and analyzing the restoration situation, unsatisfactory restoration results and damage and losses caused by repeated dismantling of cultural relics can be avoided.

[0059] The present invention is based on the high restoration characteristics of high-precision real-scene three-dimensional models, and applies them together with two-dimensional code mark recognition technology to the restoration effect analysis of cultural relics after disassembly, accurately analyzing the relative position relationship between different blocks, and has good technical feasibility.

[0060] The present invention adopts high-precision real-scene 3D modeling technology and two-dimensional code mark recognition and analysis technology, combines AR technology, high-precision real-scene 3D modeling technology, two-dimensional code recognition technology, and intelligent terminals, and establishes a complete set of portable automatic analysis methods for the disassembly and restoration effects of cultural relics, thereby realizing automatic analysis of the restoration effects of cultural relics and improving the reliability of the analysis. In actual operation, the present invention can realize automatic analysis of the restoration of cultural relics by taking pictures, thus avoiding a large amount of measurement work;

[0061] The present invention can be used for real-time inspection in the restoration process of dismantled cultural relics. By taking real-time photos and analyzing the restoration situation, unsatisfactory restoration effects and damage and losses caused by repeated dismantling of cultural relics can be avoided.

[0062] The above is a further detailed description of the present invention in combination with specific embodiments, and it cannot be determined that the specific implementation of the present invention is limited to this. For ordinary technicians in the technical field to which the present invention belongs, making several equivalent substitutions or obvious modifications without departing from the concept of the present invention, and having the same performance or use, should be regarded as belonging to the patent protection scope of the present invention determined by the submitted claims.

Claims

1. A comparative analysis method for relative positions of cultural relics dismantled and restored using a real-life three-dimensional model, characterized in that: The steps include: Step S100: First, the individual components of the cultural relics to be disassembled are marked with QR codes respectively, and then the real-scene three-dimensional information is collected and a real-scene three-dimensional model containing the QR code information is established; the cultural relics to be disassembled containing the QR code are scanned by a ground three-dimensional laser scanner to collect a three-dimensional laser point cloud; a data camera is used to take pictures to collect texture information of the cultural relics to be disassembled; a real-scene three-dimensional model of the cultural relics to be disassembled containing the QR code information is constructed by modeling software; the QR code information includes the spatial coordinates and relative order of each basic point of the QR code; Step S200: Identify and register the spatial coordinates of the real-scene 3D model and its QR code information; Step S300: photograph the restored cultural relics to obtain a photographic image, and obtain a projection image by adjusting the virtual camera of the real-scene 3D model to the same viewing angle; determine the restoration effect by comparing the coordinate difference between the photographic image after the cultural relics are disassembled and restored and the basic points of the QR code corresponding to the projection image; specifically, the following steps are included: Step S310: collecting photographic images of all restored cultural relics marked with QR codes; Step S320: Identify and register the spatial coordinates of the real-scene 3D model and its QR code information based on the restored photographic image of the cultural relic; Step S330: obtaining a projection image that matches the restored photographic image of the cultural relic; Step S340: comparative analysis of restoration effects based on image comparison; Step S350: List the QR codes with problems in the comparison and analysis results to facilitate staff review.

2. The relative position comparison and analysis method for disassembling and restoring cultural relics using a real-scene three-dimensional model according to claim 1 is characterized in that: Step S320 includes the following steps: Step S321: using the restored cultural relic photographic image acquired in step S310, identifying the QR code information on the restored cultural relic photographic image; Step S322: Select a QR code on the restored cultural relic photographed image, query and find the QR code on the real-scene 3D model in the virtual scene corresponding to the QR code; Step S323: Based on the correspondence between the basic points on the two QR codes of the photographed image in step S322, the camera pose matrix is ​​solved to complete the tracking and registration of all restored cultural relic QR codes to the real-scene three-dimensional model QR codes in the virtual scene; the camera pose matrix refers to the position relationship of the camera relative to the object during shooting, so as to set the various parameters of the camera in the virtual scene accordingly.

3. The relative position comparison and analysis method for disassembling and restoring cultural relics using a real-scene three-dimensional model according to claim 1 is characterized in that: Step S340 includes the following steps: Step S341: establishing a correspondence between basic points in the QR code in the photographed image and the projected image through QR code image recognition; Step S342: Taking the first basic point of the scene registration QR code in step S330 as the image origin and taking pixels as the unit, a photographed image coordinate system is established; The coordinate point in the projected image corresponding to the first basic point of the QR code is used as the image origin, and the projected image coordinate system is established in pixels; finally, the photographed image coordinate system and the projected image coordinate system are merged into one image coordinate system; Step S343: In the image coordinate system, the image coordinates of the corresponding points in the photographed image and the projected image are compared. If the coordinate difference between the corresponding points is less than a threshold, it is considered that the restoration effect is good.

4. The relative position comparison and analysis method for disassembling and restoring cultural relics using a real-scene three-dimensional model according to claim 1 is characterized in that: Step S340 can also be replaced by the following steps: by restoring the QR code base points in the photographed image of the cultural relics, using the inverse transformation of the projection matrix, solving the corresponding points on the real-scene three-dimensional model, and then further analyzing the spatial deviation between the corresponding points and the QR code base points on the real-scene three-dimensional model, thereby achieving a comparative analysis of the restoration effect.