CN113291075A

CN113291075A - Fresco duplicating method

Info

Publication number: CN113291075A
Application number: CN202110228165.4A
Authority: CN
Inventors: 付常青
Original assignee: Guangzhou Hanyue Data Processing Technology Co ltd
Current assignee: Guangzhou Hanyue Data Processing Technology Co ltd
Priority date: 2021-03-01
Filing date: 2021-03-01
Publication date: 2021-08-24
Anticipated expiration: 2041-03-01
Also published as: CN113291075B

Abstract

The invention discloses a mural reproduction method, which is used for reproducing ancient or modern murals combined with landforms into entity copies which can be watched in a short distance; the method is characterized in that: the mural reproduction method comprises the following steps: a step of collecting mural images; processing mural data; the step of restoring the base layer of the mural: manufacturing a mural ground layer by using clay and an aluminum honeycomb plate; and (5) UV printing. The invention achieves the technical effects that: the accuracy of the color of the wall painting is high; the mural ground layer is light; the base layer of the mural is firm and not easy to be damaged and fall off.

Description

Fresco duplicating method

Technical Field

The invention relates to the field of cultural relic artworks and art archaeological museums, in particular to a method for high-precision image acquisition, light output, color management, cultural relic image data processing, mural ground layer manufacturing and mural printing and copying of ancient murals.

Background

The protection problem of ancient murals is always a major research subject which puzzles the cultural relics department and needs to be solved urgently. The existing rich wall paintings have more urgent and difficult protection tasks. The copying method and the new technical means are applied to mural protection, and not only can be an application technology for actually recording mural files, but also can be an auxiliary means for protecting and repairing the murals.

The establishment of comprehensive and real mural image archives is the basis of all research and interpretation. The wall painting is visual artistic image and is also the image storage carrier of ancient documents. The past mural archives often adopt image log to explain the method of adding photos and copying. These methods have undoubtedly a certain reference value, but are missing in at least two respects: firstly, character recording and copying may cause the deviation of 'recreating' due to different knowledge and cognition levels of participants and high skill level, and the true state of an object cannot be reflected; secondly, the picture is used for reflecting the mural, the size and the material of the mural are obviously different from those of the original mural, and the psychological distance is easily generated. The introduction of the duplication of the original size, the original color, the original appearance and the raw material into the works of mural data collection and mural archives can make up the defects to the utmost extent, provide solid materials for future research and utilization, and lay a solid foundation.

The design of new solutions using mural reproduction that is simple and convenient and cost-effective to implement remains a endeavor for those skilled in the art.

Disclosure of Invention

One of the purposes of the invention is to restore the mural ground layer and to use the UV printing and copying technology to ensure the appearance of the mural to the maximum extent.

One of the purposes created by the invention is realized by adopting the following technical scheme:

the mural copying method is used for copying the ancient or modern mural combined with the landform into an entity copy which can be viewed at a short distance;

the method is characterized in that: the mural reproduction method comprises the following steps:

a step of collecting mural images:

sequentially shooting from left to right along the shooting direction of the same row by using a rail-moving mural acquisition system; determining sampling resolution, and calculating an actual shooting range according to the actual resolution; the overlapping rate of two adjacent images is 40% -50%; calculating the number of shooting lines according to the length, the actual shooting range and the overlapping rate of the shot image; the mural acquisition system comprises a digital camera, light and a guide rail;

taking a color chip before taking a picture of a mural image with the digital camera each time, and re-taking a color chip with a light source changed; storing the digital information file of the color card, called as a digital camera color card file;

taking pictures of mural images, and storing the pictures as original mural image files;

the digital camera color card file and the original mural image file are collectively called mural information acquisition data;

mural data processing steps:

according to the digital camera color card file, making a digital camera color management characteristic file by using color management equipment and software;

the digital camera color management characteristic file and the original mural image file are synthesized into a primary color mural image file, namely mural information processing data, by using the color management equipment and software;

the step of restoring the base layer of the mural:

manufacturing a mural ground layer by using clay and an aluminum honeycomb plate;

UV printing:

debugging the UV printer, performing ink amount control of the printer by using EFI software, wherein the debugging substep is as follows:

first ink amount control substep S401: printing a first ink quantity control test strip, and primarily testing the ink quantity range of 200- & gt 400- & gt;

the second ink amount control sub-step S402: controlling a test strip according to the printed first ink amount, reading the ink amount through a spectrophotometer, narrowing the ink amount range to perform the second step of ink amount control, and printing a second ink amount control test strip;

third ink amount control sub-step S403: determining the ink amount range to the proper ink amount of the mural ground layer by reading the ink amount control of the second step, and printing a third step ink amount test strip on the mural ground layer to obtain an accurate ink amount value;

generating a media ink amount linearization file substep S404: reading a color card of a medium by using the third ink quantity control test strip printed on the mural ground layer to generate a medium ink quantity linearization file;

generating a mural ground layer color ICC profile substep S405: printing a color block file on the mural base layer, and generating a mural base layer color ICC characteristic file;

according to the ICC profile of the color of the base layer of the mural, the color of the mural is restored, and the method comprises the following substeps:

the generate personalized printer driver substep S406: importing the ink quantity linearization file of the mural ground layer and the color ICC characteristic file of the mural ground layer into the EFI software to generate a combined data file image, namely a personalized printer driver, for controlling the printer;

printing primary color mural substep S407: and controlling the printer by using the primary color mural image file compensated by the ICC curve and by means of the personalized printer driver, and printing a copy of the mural on the mural ground layer.

According to other aspects of the present disclosure, one or more of the features described herein may also be included. As long as such a combination of features is practicable, new technical solutions formed by the features are part of the invention.

Compared with the prior art, the invention has the beneficial effects that:

the ancient method for copying the wall paintings can centralize and display the wall paintings in different places in full breadth and original size, so that a viewer has a chance to carefully watch the wall paintings in a short time and in a short distance;

the ancient murals are used for exhibition after being copied, so that visitors do not need to go to ancient buildings, stone cave temples or coffin rooms for visiting, and the ancient murals play an important role in cultural relics protection.

Drawings

The features, advantages and characteristics of the present invention will be better understood by the following description of specific embodiments with reference to the accompanying drawings, in which:

FIG. 1: the invention creates a schematic block diagram of the simple flow steps of the mural reproduction method;

FIG. 2: the preparation material schematic diagram of the clay layer of the mural reproduction method is provided by the invention, which is glue, sand and stone and gypsum respectively;

FIG. 3: the mural ground layer preparation material schematic diagram of the mural reproduction method is respectively a clay aerospace honeycomb plate and an aluminum aerospace honeycomb plate;

FIG. 4: the mud layer schematic diagram of the mural reproduction method is a first coarse mud layer which is prepared by mixing sand, mud and glue; the second mud layer is prepared by mixing lime cream, mud and glue; the third lime layer is prepared by mixing lime cream and glue;

FIG. 5: the track splicing method of the mural reproduction method provided by the invention is used for collecting schematic diagrams;

FIG. 6: the schematic diagram of the SG color card used in the mural reproduction method of the invention;

FIG. 7: the invention creates a schematic diagram of the picture content of the original mural image file of the mural copying method, wherein the color values RGB of the pixel points corresponding to the image blocks in the small red frame in the picture are displayed in a list below;

FIG. 8: the ICC characteristic curve data schematic diagram of the digital camera color card file of the mural copying method is created by the invention;

FIG. 9 a: a data image before compensation is performed on color value RGB + ICC characteristic curve data of a pixel point corresponding to an image block in a small red box in the mural picture in fig. 7;

FIG. 9: the invention creates a picture content schematic diagram of primary color mural image files of the mural copying method, corresponding real color images of the murals;

FIG. 10: the schematic diagram of the UV printing step of the mural reproduction method is used for solving the problem that UV printing is carried out on a mural ground layer;

FIG. 11: the UV printing step schematic diagram of the mural reproduction method created by the invention shows the information abstract of ink amount control;

FIG. 12: schematic diagram of the UV printing apparatus used for the mural reproduction method created by the present invention;

FIG. 13: the invention creates a schematic diagram of UV printing equipment used in the mural reproduction method, wherein during printing, ancient taken murals are finally reproduced.

The manufactured base layer simulates the removal of murals, so that the base layer is not completely flat.

Detailed Description

The invention is further described below in conjunction with the attached drawings and the detailed description.

The design concept created by the invention

Fig. 1 shows a schematic block diagram of a simplified flow of steps of the mural reproduction method created by the present invention.

The mural is attached to the building, and the fate of the mural is related to the safety and danger of the ancient building. Once an ancient mural disappears, all the historical cultural information contained in the ancient mural disappears. The ancient technology for copying the wall painting is applied to the field of protecting and repairing the wall painting, can truly record the information of the wall painting, provides a basis for protecting and repairing the wall painting, and becomes a new means and method. The method records the current situation of the mural and the pathological change situation through means such as high-precision acquisition, data processing, ground layer manufacturing, UV printing technology and the like; recording damage distribution of the murals, establishing complete ancient murals and endangered mural disease files by matching with other means according to specific conditions, and analyzing mural materials and structures through the images and the information records to provide accurate basis and first-hand materials for mural repair experts, art and archaeological workers. Provides a feasible scheme for the display of ancient murals. Ancient murals are precious and fragile, are scattered all over the country, are inconvenient to traffic, and are not easy to view on the spot. The wall painting is painted on a cave or a wall of an ancient building or applied to an ancient coffin chamber, the general breadth is huge, the wall painting is attached to the wall painting and cannot move, and in addition, the environmental influences such as on-site light rays and the like are added, so that the wall painting is almost impossible to watch comprehensively and carefully in a short period, and therefore, the propagation of the ancient wall painting has great limitation, and the difficulty in publicity, display and communication is great. The prior mural transmission and display means are mostly album prints and copy copies, and the limitation is obvious. Due to the characteristics and limitations of the printed matter, the printed matter has a great distance from the original mural painting in the aspects of the size, the texture of materials, the tone atmosphere, the definition degree and the like. Most of printed matters are local, the overall appearance of the mural cannot be reflected, and the scene feeling and the visual impact of the mural are avoided; the copy quality of the copy is different due to cultural cultivation and artistic cultivation of the copy person and the skill level.

The ancient mural reproduction technology provided by the invention adopts the ancient mural high-precision acquisition, data processing, mural ground layer manufacturing and UV printing reproduction technology, so that the ancient mural reproduction technology has the precious property and scientific authenticity of the traditional technology. Not only ensures the high reduction of the mural duplicate, but also can objectively reflect the real appearance of the mural. The ancient times disclose the copying technology of the mural, can be with the mural of different places, with full breadth, former big size, concentrate the show, make the visitor have the opportunity in the short time, closely watch the mural carefully. Such a presentation allows the viewer to obtain valuable insight and gains from both an artistic history perspective, aesthetic appreciation and academic research. The ancient murals are used for exhibition and visitors after being copied, do not need to go to ancient buildings, stone cave temples or coffin houses for visiting, and play an important role in protecting cultural relics, so that the digital protection of the ancient murals has milestone significance for the safety of the cultural relics, and plays a decisive role in protecting the cultural relics of the ancient murals.

Base layer of ancient wall painting

The ancient mural ground layer mainly appears in ancient cultural sites, ancient tombs, ancient buildings, stone cave temples and the like in China.

The materials of construction of the mural base layer or so-called mural base layer board are shown in fig. 2, which are glue, gravel and gypsum, respectively.

Fig. 3 shows schematic diagrams of materials for preparing a mural ground layer of the mural replication method, which are made of clay and aluminum aerospace honeycomb plates respectively.

Making of base layer of wall painting

FIG. 4 is a schematic diagram of the clay layers of the mural reproduction method of the present invention, which are the first coarse clay layers made of sand, mud and glue; the second mud layer is prepared by mixing lime cream, mud and glue; the third lime layer is prepared by mixing lime cream and glue.

The advantages of the exhibit

a. Accuracy of reducing mural color

The accurate reduction color has important significance for truly reflecting the mural painting and is helpful for splicing in the later period, and the accurate reduction color facilitates the splicing work to a great extent. It is unlikely that the traditional silver salt film could achieve accurate gray balance of the whole picture, so the inventor often finds more or less color difference between two images in the later period, which causes great difficulty to splicing work, but after obtaining the image through digital back, the professional color control technology is introduced in the later digital image file processing to conveniently achieve the predetermined color reduction index. And each digital image and the special color description file generated for the image are stored together, so that the colors of the mural can be accurately restored wherever the mural is.

b. Light weight of mural ground layer

The aluminum honeycomb plate has the advantages of light weight, high strength, high rigidity and the like. The aluminum hexagonal honeycomb is arranged in the center, the density is small (about 3-7 kilograms per square meter), the weight of the building block board is 1/5 which is equal to the weight of the building block board with the same thickness and the same surface, the glass is 1/6, the aluminum is 1/7, the building block board is waterproof, moistureproof and free of harmful gas release, the specific strength of unit mass is large, the specific rigidity is high (the structural rigidity is 1.7 times of rib type), the building block board is not easy to deform, the defects of deformation, middle collapse and the like of other decorative boards when the area of a single block is large are completely overcome, the edge folding can be cut randomly, the service life of the product can be ensured to be more than 30 years by the surface fluorocarbon coating, the surface of the aluminum honeycomb board has extremely high flatness, and the anti-seismic performance is good

c. Firm, uneasy to be damaged and fall off

The mural ground layer is made of natural materials, the lining plate is made of aviation aluminum materials, and the aviation aluminum materials have the history of more than one hundred years and complete technological processes, so that the wall painting ground layer and the aviation aluminum materials are organically combined together to form a mud board which is firm and not easy to damage and drop.

The coffin chamber mural is made of the soil near the coffin chamber to make a base layer.

The ancient building mural painting adopts soil near the ancient building to make a base layer.

The ground layer is made of soil near the cave temple.

The inventor finds that the clay in Gansu, Tibet, Shaanxi, Shanxi, Hebei and the like has different viscosity, texture and density. Therefore, it is very important to take soil in situ to make the base layer.

Data acquisition and processing

Fig. 5 shows a schematic diagram of the track splicing method acquisition of the mural reproduction method created by the present invention.

a. Measures taken for obtaining dpi of original large mural painting

Using Cambo WDS Back-Shift Flat Panel professional Camera, Leaf Aptus 8000 ten thousand pixels digital Back

The format of the acquisition file uses RAW, the color gamut is Adobe RGB, the digital lens of Schneider high-definition large image field and the illumination of German Kangsu spotlight; shooting in sequence from left to right in the shooting direction of the same row, determining sampling resolution, and calculating an actual shooting range according to actual resolution; the overlapping of two adjacent images is 40-50%, the number of shooting lines is calculated according to the length of the shot image, the actual shooting range and the overlapping rate, and shooting data is recorded in detail.

Distance of shooting

In the case of the specified sampling resolution, the inventor calculates the distance between the camera and the object plane cultural relic according to the effective pixel of the digital back, the CCD effective area, the lens and other factors, and when 8000 ten thousand pixels CCD is used, the shooting distance of about 2 meters is used, and the obtained data is collected, and the precision is 400 dpi.

Track splicing method shooting

Under the specified sampling resolution, a shooting object cannot be shot by one image due to overlarge area, the shooting object is collected in a multi-image-field mode, a camera is parallel to a shot cultural relic, a plurality of images are shot, and the spliced area of the images is the whole picture of a wall painting in a coffin chamber or an ancient building.

Degree of contact

The overlapping rate of two adjacent images reaches more than 40 percent, so that the conditions of dislocation and insufficient picture width can not occur during splicing.

Image cropping

According to the characteristics of a lens and a digital back CCD, a single shot image only utilizes an image with higher middle quality to cut the surrounding part of the image so as to obtain the high level of the whole picture.

Large foot stool

For a support for taking a frame image, the inventors mounted a Cambo WDS back shift technology type camera using a large professional tripod of approximately 3 meters height.

b. Principle of protection

The non-contact acquisition equipment is used, the acquisition process is not in physical contact with the cultural relics, the damage to the cultural relics is avoided, a continuous light source is not used, and the used German flash lamp has accurate color temperature and does not contain ultraviolet rays; an anti-UV filter is loaded in front of the lamp light to effectively filter ultraviolet rays, so that the light source cannot damage the cultural relics.

c. Color reduction (color management)

It is the purpose of the work to restore the true painting art and true color of the mural. If the color restoration is well controlled, much labor is saved in later splicing work, so that a special color Profile (ICC Profile) needs to be manufactured for a shot image. Before formal shooting, a color card needs to be shot, when a light source is changed, a color card needs to be shot again, and the color card file and the shot image file are stored together. And after the color card is shot, formal shooting work can be carried out.

The SG color card is collected before the mural is collected. Fig. 6 shows a schematic diagram of SG color chips used in the mural reproduction method of the present invention.

And establishing a color management Profile (ICC Profile) of the camera by using X-rite professional color management equipment and software.

After the original mural works are scanned in a high-definition mode and high-definition image data are processed, the inventor obtains a high-precision mural Tiff image file, and then works of ink quantity testing and ICC color control of a mural ground layer are carried out by software, and the method mainly comprises the following steps:

1. and generating an ICC curve file by using a color card file acquired by the inventor on site so as to control the output real color range.

The same digital camera is used for shooting 140 colors of the standard color card plate, and the difference between the real color value and the standard color value of the color card photo is compared, so that the color ICC curve is generated.

2. The color value RGB of the pixel points corresponding to the image blocks in the small red frame in the mural picture is as follows.

Fig. 7 shows a schematic diagram of the picture content of the original mural image file of the mural copying method created by the present invention, wherein the color values RGB of the pixel points corresponding to the image blocks in the small red frame in the picture are displayed in the following list, and the RGB values are:

R	G	B
			95	46	44

fig. 8 is a schematic diagram showing ICC profile data of a digital camera color card file of the mural copying method of the present invention.

The data compensated by the color value RGB + ICC characteristic curve data of the pixel points corresponding to the image blocks in the small red box in the mural picture is shown in fig. 9a, where the RGB values are:

R	G	B
				114	56	54

UV printing

UV printing is carried out on the mural ground layer.

Fig. 10 shows a schematic diagram of the UV printing step of the mural reproduction method of the present invention, which finds UV printing on the mural ground layer.

After the original mural works are subjected to high-definition acquisition and high-definition image data processing, the inventor obtains a high-precision mural Tiff image file, and then performs ink quantity testing and ICC color control on a mural ground layer by using software, and the method mainly comprises the following steps:

a. ink volume control

And debugging the UV printer, and controlling the ink amount of the printer by using EFI software.

Firstly, printing an ink quantity control test card, and preliminarily testing the ink quantity range (200-400).

Secondly, reading the ink amount (by a spectrophotometer) according to the printed ink amount control strip, and then reducing the ink amount range to perform the ink amount control of the second step.

And thirdly, determining the range to the appropriate ink amount of the mural ground layer by reading the ink amount control of the second step, and printing a third step ink amount test strip on the mural ground layer to obtain an accurate ink amount value.

FIG. 11: the UV printing step schematic diagram of the mural reproduction method created by the present invention shows the information abstract of ink amount control.

Fourthly, reading the color card of the medium by the test strip printed on the mural ground layer to generate the ink quantity linearization file of the medium.

Fifthly, printing the color block file on the mural ground layer to obtain the color ICC profile of the mural ground layer.

b. Making an icc color characteristic file and accurately restoring the colors of the mural

And importing the ink quantity linearization file of the mural ground layer and the color ICC characteristic file of the mural ground layer into EFI software to generate a combined data file image which is equivalent to a personalized printer driver and controls the printer.

And controlling the printer by using the ancient high-definition mural file picture compensated by the ICC curve and by means of the personalized printer driver, and printing a copy close to a real mural on the manufactured mud board.

c. Accuracy of printing

1. And importing the data file into EFI software, and carrying out UV printing output with the precision of 180 dpi.

2. Finally, ink amount control and color management are carried out through EFI, and the obtained mural ICC color feature file and the mural ground layer ink amount value can be copied to obtain the ancient torn murals which are basically consistent with the original mural colors and mediums.

3. From the printing point of view, the printing can be carried out on the materials with flat surfaces.

Because the UV ink is cured instantly in milliseconds, the UV ink can be cured and dried without a special coating to form a picture. If the ink adhesion firmness is considered, the ink adhesion is different because the surface energy of different materials is different, but the ink adhesion is not suitable for all material characteristics. The current solution in the industry is to apply a special coating treatment liquid to the surface of the material before printing to increase the surface energy of the material and thus improve the adhesion (fastness) of the ink.

FIG. 12 is a schematic view of a UV printing apparatus used in the inventive mural reproduction method;

fig. 13 is a schematic view of a UV printing apparatus used in the invented mural reproduction method, wherein UV printing is in progress to eventually reproduce the ancient removed mural.

The technical scheme of the invention

According to the embodiment of the invention, the mural reproduction method is used for reproducing ancient or modern murals combined with landforms into entity copies which can be viewed at a close distance;

the difference with the prior art is that the mural reproduction method comprises the following steps:

a step of collecting mural images:

mural data processing steps:

the step of restoring the base layer of the mural:

UV printing:

Preferably, the UV printing step further comprises a printing precision adjustment sub-step of:

when the personalized printer driver is imported into the EFI software for UV printing output, the printing precision is 180 dpi;

and performing ink amount control and color management through the EFI software to obtain the mural ICC color profile and the mural ground layer ink amount value, and copying mural copies consistent with the original mural colors and media.

Preferably, the mural reproduction method further comprises the following steps: before the mural duplicate is printed and output, coating the surface of the mural ground layer with a treatment liquid of the ink adhesion enhancing coating for increasing the surface energy of the material.

Preferably, the mural collection system further comprises a light meter, and the digital camera comprises a lens and a digital back.

Preferably, the aluminum honeycomb plate is an aluminum aerospace honeycomb plate, and the middle layer is an aluminum hexagonal honeycomb.

Preferably, the mural is a coffin chamber mural, and soil for manufacturing a base layer of the mural is manufactured by soil near the coffin chamber; or,

the mural is a historic building mural, and soil for manufacturing a base layer of the mural is made of soil near the historic building; or,

the wall painting is a cave temple wall painting, and soil on the ground layer of the wall painting is made of soil near the cave temple.

Preferably, the clay of the mural ground layer is divided into three layers: the first coarse muddy soil layer is prepared by mixing sand, mud and glue; the second mud layer is prepared by mixing lime cream, mud and glue; the third lime layer is prepared by mixing lime cream and glue.

Preferably, in the step of acquiring the mural image, the original mural image file format uses RAW, and the color gamut is Adobe RGB.

Preferably, in the mural image collection step, in the case of using a 8000 ten thousand pixel CCD, the accuracy of the collected mural information collection data is 400dpi at a shooting distance of 2 meters.

Preferably, in the mural image collection step, the lamp light does not contain ultraviolet rays; and an anti-UV filter is loaded in front of the lamplight to filter the irradiation of ultraviolet rays.

Preferably, in the mural data processing step: and shooting 140 colors of the standard color card plate by using the digital camera, and comparing the difference between the real color value and the standard color value of the color card photo to generate a color ICC curve.

The technical scheme has the beneficial effects that:

the accuracy of the color of the wall painting is high;

the mural ground layer is light;

the base layer of the mural is firm and not easy to be damaged and fall off.

The foregoing detailed description of preferred or specific embodiments of the invention has been presented. It should be understood that numerous modifications and variations can be devised by those skilled in the art in light of the present teachings without departing from the spirit and scope of the invention. Therefore, the technical solutions available to those skilled in the art through logic analysis, reasoning and limited experiments based on the design concept of the present invention should be within the scope of the present invention and/or the protection scope defined by the claims.

Claims

1. A mural reproduction method for reproducing an ancient or modern mural combined with a landscape into an entity reproduction capable of being viewed at a close distance;

a step of collecting mural images:

mural data processing steps:

the step of restoring the base layer of the mural:

UV printing:

2. The mural reproduction method according to claim 1, wherein: the UV printing step further comprises a printing precision adjustment substep of:

3. The mural reproduction method according to claim 1 or 2, wherein: further comprising the steps of: before the mural duplicate is printed and output, coating the surface of the mural ground layer with a treatment liquid of the ink adhesion enhancing coating for increasing the surface energy of the material.

4. The fresco reproduction method according to any one of claims 1 to 3, characterized in that: the mural acquisition system further comprises a light meter, and the digital camera comprises a lens and a digital back.

5. The fresco reproduction method according to any one of claims 1 to 4, characterized in that: the aluminum honeycomb plate is an aluminum aerospace honeycomb plate, and the middle layer is an aluminum hexagonal honeycomb.

6. The fresco reproduction method according to any one of claims 1 to 5, characterized in that: the wall painting is a coffin chamber wall painting, and soil for manufacturing a ground layer of the wall painting is manufactured by soil near the coffin chamber; or,

7. The fresco reproduction method according to any one of claims 1 to 6, characterized in that: the clay on the base layer of the mural is divided into three layers: the first coarse muddy soil layer is prepared by mixing sand, mud and glue; the second mud layer is prepared by mixing lime cream, mud and glue; the third lime layer is prepared by mixing lime cream and glue.

8. The fresco reproduction method according to any one of claims 1 to 7, characterized in that: in the step of acquiring the mural image, the original mural image file format uses RAW, and the color gamut is Adobe RGB.

9. The fresco reproduction method according to any one of claims 1 to 8, characterized in that: in the mural image acquisition step, the accuracy of the acquired mural information acquisition data is 400dpi according to a shooting distance of 2 meters under the condition of using 8000 ten thousand pixels of CCD.

10. The fresco reproduction method according to any one of claims 1 to 9, characterized in that: in the step of collecting the mural image, the lamplight does not contain ultraviolet rays; and an anti-UV filter is loaded in front of the lamplight to filter the irradiation of ultraviolet rays.

11. The fresco reproduction method according to any one of claims 1 to 11, characterized in that: in the mural data processing step: and shooting 140 colors of the standard color card plate by using the digital camera, and comparing the difference between the real color value and the standard color value of the color card picture to generate a color ICC curve.