Method for checking color consistency of multiple projectors

Abstract

The invention relates to the technical field of projector colors, in particular to a method for checking color consistency of multiple projectors, which comprises the following steps of: S1, respectively acquiring optical color intensity values of single projectors; s2, collecting positioning positions of the plurality of projectors, associating color intensity values, calculating a public brightness response interval of the plurality of projectors, and recording an interval result in the form of a translation template and an attenuation template; s3, extracting a color block feature picture of a public brightness interval of the projector; extracting data in the color block features, and calculating to obtain a region deformation feature coefficient XZ; s4, calculating according to the region deformation characteristic coefficient XZ to obtain a brightness average value Yc of color block characteristics; the brightness distribution of the color block features and the brightness average value Lc of the projection color block features are obtained, a projection area and a single camera image of a projector are obtained, the mapping relation is inversely deduced to a single pixel, curved surface projection is converted into plane projection, and calibration is carried out through existing plane projection colors.

Description

Technical Field

[0001] The invention relates to the technical field of projector color technology, and in particular to a method for testing the color consistency of multiple projectors. Background Art

[0002] With the increasing demand for ultra-large screen high-resolution displays in fields such as business, entertainment, and scientific research, multi-projection technology has gradually occupied the market. Due to the performance differences between different projectors and the performance differences between different areas within the same projector, multi-projector display walls cannot project a complete visually consistent picture even with precise geometric alignment. Therefore, "color correction technology" plays a vital role in the construction of "multi-projector display walls".

[0003] In the past decade, many scholars have done a lot of research on the problem of multi-projector splicing display. Early manual correction work was cumbersome and inaccurate, and has gradually withdrawn from the field of multi-projector correction. Optical transition means achieve smooth transition of images by introducing transition functions at the boundaries of two projected images; color domain matching means achieve global color correction by matching the color domains of all projectors. However, both theory and practice show that the color gamuts of some projectors cannot be matched; since there are also changes in color and brightness inside the projector projected image, some algorithms perform change tests on each pixel by "accommodating" the properties of the worst pixel point. This method will cause a serious decrease in the contrast of the projected image. For this reason, color correction methods that use the visual characteristics of the human eye or the statistical characteristics of the image have been proposed one after another. These algorithms allow a certain difference in image color, thereby improving the contrast and color saturation of the image.

[0004] However, the current color correction method cannot adapt to any smooth curved projection screen and is overly dependent on the results of geometric correction. At the same time, since the color correction method based on CCD camera measurement requires a large number of images, its correction speed is relatively slow. Summary of the invention

[0005] The present invention provides a method and system for color consistency inspection of multiple projectors, which can calculate and reverse through a program instead of manually adjusting each projector, so that the inspection and proofreading speed is faster, and it does not need to take a large number of images, only a number of projectors need to be projected in a common interval, which promotes the beneficial effect of improving the calculation, inspection and projection speed of real-time correction, and solves the problem of over-reliance on geometric correction mentioned in the above background technology. At the same time, since the color correction method based on CCD camera measurement needs to take a large number of images, its correction speed is relatively slow.

[0006] The present invention provides the following technical solution: a method for testing the color consistency of multiple projectors, the testing method comprising:

[0007] S1, respectively collect the optical color intensity value of a single projector;

[0008] S2, collecting the positioning positions of several projectors, correlating the color intensity values, calculating the common brightness response interval of several projectors, and recording the interval results in the form of translation templates and attenuation templates;

[0009] S3, extracting the color block feature image of the common brightness range of the projector, and importing the color block features extracted from the effective area into the RGB color channel color block;

[0010] Extract the data from the color block features and calculate the area deformation feature coefficient XZ;

[0011] S4, calculate the average brightness Y of the color block feature according to the area deformation feature coefficient XZ c ; Obtain the brightness distribution of the color block feature and the average brightness L of the projected color block feature c , to the projection area and the single camera image of the projector, back to the single pixel mapping relationship, convert the curved surface projection into a plane projection, and calibrate it through the existing plane projection color.

[0012] As an optional solution of the method for color consistency inspection of multiple projectors of the present invention, the step S1 includes:

[0013] 1) Confirm the single projector and the projection angle value, projection distance, obtain the developed film projection ratio, and collect the ambient brightness and projection image size value;

[0014] 2) Obtain the projection ratio of the developed film, and then obtain the image width value and resolution value;

[0015] 3) According to the image width value and the resolution value, the color intensity value is obtained using ANSI lumens as the unit of projection brightness.

[0016] As an optional solution of the method for color consistency inspection of multiple projectors of the present invention, the step S2 includes:

[0017] 1) Obtain the positioning position values ​​of several projectors, and it is recommended to project a three-dimensional model to display the positioning position in the curved projection model;

[0018] 2) Obtain the color intensity values ​​associated with the positioning position values ​​of several projectors, and calculate the common brightness corresponding interval coefficient KX of the several projectors;

[0019] 3) The common brightness corresponding interval coefficient KX is associated with the preset translation template and attenuation template, and the area deformation characteristic coefficient XZ is obtained in the surface projection model.

[0020] As an optional solution of the color consistency inspection method for multiple projectors of the present invention, the common loudness corresponding interval coefficient KX is obtained by the following formula:

[0021]

[0022] Wherein S1 identifies the positioning distance ratio of the first projector; S2 identifies the positioning distance ratio of the first projector; S3 identifies the positioning distance ratio of the first projector, where d1 / d2 / d3 represents the brightness value of a single projector; l represents the resolution value.

[0023] As an optional solution of the color consistency inspection method of multiple projectors of the present invention, the deformation characteristic coefficient XZ is composed of a family of curves in two orthogonal directions, which is expressed as:

[0024]

[0025]

[0026] in is the i-th u line, is the jth v line, is the network point, and the entire network is recorded as M k , k indicates the number of subdivisions; construct 4-point interpolation subdivision curves along the u / v directions to encrypt the mesh and maintain the geometric shape characteristics of the mesh;

[0027] Among them, a is the tension parameter.

[0028] As an optional solution of the color consistency inspection method of multiple projectors described in the present invention, wherein: the brightness average value L c Obtained by the following formula:

[0029]

[0030] The projector projects a picture with a brightness distribution of y im The uniform grayscale image of (x1, y1) is collected by the camera, output and calculated to obtain its brightness distribution y out (x m ,y m );

[0031] The brightness channel response function of the projector camera lens satisfies monotonic reversibility and is unrelated to the chromaticity channel. Therefore, according to the camera response function, c By out (x m ,y m )The brightness uniformity distribution of the image reflected by the screen can be obtained through inverse calculation.

[0032] As an optional solution of the method for color consistency inspection of multiple projectors of the present invention, wherein: the L c (x i ,y i ) is the correction target value, then the target real image brightness uniformity distribution is obtained as And, the associated projector response function f p , and obtain the uniform ratio of the image in the figure.

[0033] As an optional solution of the color consistency inspection method of multiple projectors described in the present invention, wherein: the calibration in step S4 includes image saturation calibration, and when the calibration image is not saturated or the saturated area is small, the processing results of the two methods are consistent;

[0034] As the saturated area increases, the image is corrected by shearing;

[0035] Through the linear method and the shearing iteration method, the uniformity ratio of the associated image is optimized, and the unevenness of the projection image before and after calibration is reduced from 18.5% to 1.39%, obtaining the color consistency correction effect with the same accuracy when the image is not saturated.

[0036] As an optional scheme of the method for inspecting color consistency of multiple projectors described in the present invention, the projection ratio of the developed film includes the green-sensitive layer, red-sensitive layer and blue-sensitive layer in the film, which contain magenta dye, cyan dye and yellow dye respectively, and the concentration of the three dyes controls the spectral transmittance of the film.

[0037] As an optional solution of the method for checking color consistency of multiple projectors described in the present invention, the method is checked by a spectrophotometer and color calibration software, and the steps of the method for checking color consistency of multiple projectors according to claim 1 and claim 9 are executed by calculation through a computer program.

[0038] The present invention has the following beneficial effects:

[0039] 1. The color consistency inspection method and system for multiple projectors collects the positioning positions of several projectors, associates the instrument parameters of a single projector, associates the color intensity value of a single projector and extracts and inspects the common brightness features of the common response interval of the projection, extracts the deformation characteristic coefficient of the area, calculates the brightness average value and reversely deduce the mapping relationship of a single pixel, so as to facilitate the inspection and calibration of color consistency. Since the calculation and reverse deduction are performed by the program instead of manually adjusting each projector, the inspection and proofreading speed is faster, and there is no need to take a large number of images. It only needs several projectors to project the common interval and associate the parameters of the projector itself for calculation.

[0040] 2. The color consistency inspection method and system for multiple projectors can perform real-time color correction calculations pixel by pixel on any smooth and continuous projection screen. The method is based on a simple, stable, and high-precision subdivision grid method to encrypt the initial sampling grid. Compared with the traditional dense sampling method, the data for measuring the initial data is greatly reduced, and the projector brightness response curve is calculated based on the weighted least squares curve fitting idea. The measurement data for the projector brightness response curve is reduced from the traditional 256 HDR images to only a single HDR image. In terms of program implementation, the method in this paper uses GPU pixel shaders to accelerate the correction calculation process and promote the calculation speed of real-time correction.

[0041] 3. The color consistency inspection method and system for multiple projectors obtains the optimal value of the uniformity ratio of related images through the linear method and the shearing iteration method, reducing the unevenness of the projected images before and after calibration from 18.5% to 1.39%, and obtaining the color consistency correction effect with the same accuracy when the image is not saturated, thereby improving the accuracy of inspection and proofreading. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 Schematic diagram of the process steps of the system of the present invention.

[0043] Figure 2 It is a schematic diagram of the system flow of the present invention.

[0044] Figure 3 It is a schematic diagram of the XZ network arrangement of the deformation characteristic coefficients of the present invention.

[0045] Figure 4 Schematic diagram of intensity curves of several projector pairs of the present invention. DETAILED DESCRIPTION

[0046] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0047] Example 1

[0048] In the past decade, many scholars have done a lot of research on the problem of multi-projector splicing display. Early manual correction work was cumbersome and inaccurate, and has gradually withdrawn from the field of multi-projector correction. Optical transition means achieve smooth transition of images by introducing transition functions at the boundaries of two projected images; color domain matching means achieve global color correction by matching the color domains of all projectors. However, both theory and practice show that the color gamuts of some projectors cannot be matched; since there are also changes in color and brightness inside the projector projected image, some algorithms perform change tests on each pixel by "accommodating" the properties of the worst pixel point. This method will cause a serious decrease in the contrast of the projected image. For this reason, color correction methods that use the visual characteristics of the human eye or the statistical characteristics of the image have been proposed one after another. These algorithms allow a certain difference in image color, thereby improving the contrast and color saturation of the image.

[0049] However, the current color correction method cannot adapt to any smooth curved projection screen and is overly dependent on the results of geometric correction. At the same time, since the color correction method based on CCD camera measurement requires a large number of images, its correction speed is relatively slow.

[0050] The present invention provides the following technical solution: A method for testing the color consistency of multiple projectors, please refer to Figure 1 - Figure 4 , the test method includes,

[0051] S1, respectively collect the optical color intensity value of a single projector;

[0052] S2, collecting the positioning positions of several projectors, correlating the color intensity values, calculating the common brightness response interval of several projectors, and recording the interval results in the form of translation templates and attenuation templates;

[0053] S3, extracting the color block feature image of the common brightness range of the projector, and importing the color block features extracted from the effective area into the RGB color channel color block;

[0054] Extract the data from the color block features and calculate the area deformation feature coefficient XZ;

[0055] S4, calculate the average brightness Y of the color block feature according to the area deformation feature coefficient XZ c ; Obtain the brightness distribution of the color block feature and the average brightness L of the projected color block feature c , to the projection area and the single camera image of the projector, back to the single pixel mapping relationship, convert the curved surface projection into a plane projection, and calibrate it through the existing plane projection color.

[0056] The program is written in OpenGL and GLSL (OpenGL Shading Language). The color attenuation template, translation template and linearization lookup table are calculated in advance according to the brightness information of each projector obtained in step S1, loaded into the graphics card memory in the form of texture, and the pixel shader (FragmentShader) is used to perform pixel-by-pixel color correction calculation on the projected image.

[0057] In this embodiment, the positioning positions of several projectors are collected, the instrument parameters of a single projector are associated, the color intensity values ​​of a single projector are associated, and the common brightness features of the common response interval of the projection are extracted and tested. The deformation characteristic coefficient of the extraction area is used to calculate the brightness average and reverse the mapping relationship of a single pixel, so as to facilitate the inspection and calibration of color consistency. Since the calculation and reverse deduction are performed by the program instead of manually adjusting each projector, the inspection and proofreading are faster and there is no need to take a large number of images. It only needs several projectors to project the common interval and associate the parameters of the projector itself for calculation.

[0058] Example 2

[0059] This embodiment is an explanation of embodiment 1, and specifically, the step S1 includes:

[0060] 1) Confirm the single projector and the projection angle value, projection distance, obtain the developed film projection ratio, and collect the ambient brightness and projection image size value;

[0061] 2) Obtain the projection ratio of the developed film, and then obtain the image width value and resolution value;

[0062] 3) According to the image width value and the resolution value, the color intensity value is obtained using ANSI lumens as the unit of projection brightness.

[0063] In this embodiment, by collecting the angle value, projection distance, and projection ratio of the developed film of a single projector, as well as the specific parameters such as the ambient brightness and the projected image size value, a single color intensity value is obtained, which is convenient for later testing of multiple projectors.

[0064] Example 3

[0065] This embodiment is an explanation of embodiment 1. For details, please refer to Figure 1 - Figure 4 , wherein: the step S2 includes:

[0066] 1) Obtain the positioning position values ​​of several projectors, and it is recommended to project a three-dimensional model to display the positioning position in the curved projection model;

[0067] 2) Obtain the color intensity values ​​associated with the positioning position values ​​of several projectors, and calculate the common brightness corresponding interval coefficient KX of the several projectors;

[0068] 3) The common brightness corresponding interval coefficient KX is associated with the preset translation template and attenuation template, and the area deformation characteristic coefficient XZ is obtained in the surface projection model.

[0069] Wherein: the common loudness corresponding interval coefficient KX is obtained by the following formula:

[0070]

[0071] Wherein S1 identifies the positioning distance ratio of the first projector; S2 identifies the positioning distance ratio of the first projector; S3 identifies the positioning distance ratio of the first projector, where d1 / d2 / d3 represents the brightness value of a single projector; l represents the resolution value.

[0072] Wherein: the deformation characteristic coefficient XZ is formed by curves in two orthogonal directions, which is expressed as:

[0073]

[0074]

[0075] in is the ith u line, V i k is the jth v line, is the network point, and the entire network is recorded as M k , k indicates the number of subdivisions; construct 4-point interpolation subdivision curves along the u / v directions to encrypt the mesh and maintain the geometric shape characteristics of the mesh;

[0076] Among them, a is the tension parameter.

[0077] Where: the average brightness L c Obtained by the following formula:

[0078]

[0079] The projector projects a picture with a brightness distribution of y im The uniform grayscale image of (x1, y1) is collected by the camera, output and calculated to obtain its brightness distribution y out (x m ,y m );

[0080] The brightness channel response function of the projector camera lens satisfies monotonic reversibility and is unrelated to the chromaticity channel. Therefore, according to the camera response function, c By out (xm ,y m )The brightness uniformity distribution of the image reflected by the screen can be obtained through inverse calculation.

[0081] Where: L c (x i ,y i ) is the correction target value, then the target real image brightness uniformity distribution is obtained as And, the associated projector response function f p , and obtain the uniform ratio of the image in the figure.

[0082] In this embodiment, real-time color correction calculation can be performed pixel by pixel on any smooth and continuous projection screen. The method encrypts the initial sampling grid based on a simple, stable and high-precision subdivision grid method. Compared with the traditional dense sampling method, the data for measuring the initial data is greatly reduced, and the projector brightness response curve is calculated based on the weighted least squares curve fitting idea. The measurement data for the projector brightness response curve is reduced from the traditional 256 HDR images to only a single HDR image. In terms of program implementation, the method in this paper uses GPU pixel shaders to accelerate the correction calculation process to achieve real-time correction calculation speed.

[0083] Example 4

[0084] This embodiment is an explanation of the embodiment 1, specifically: the calibration in step S4 includes image saturation calibration, when the calibration image is not saturated or the saturation area is small, the processing results of the two methods are consistent;

[0085] As the saturated area increases, the image is corrected by shearing;

[0086] Through the linear method and the shearing iteration method, the uniformity ratio of the associated image is optimized, and the unevenness of the projection image before and after calibration is reduced from 18.5% to 1.39%, obtaining the color consistency correction effect with the same accuracy when the image is not saturated.

[0087] Among them: the developed film projection ratio includes the green-sensitive layer, red-sensitive layer, and blue-sensitive layer in the film, which contain magenta dye, cyan dye, and yellow dye respectively. The concentration of the three dyes controls the spectral transmittance of the film.

[0088] Wherein: the method is tested by a spectrophotometer and color calibration software, and the steps of the color consistency test method of multiple projectors according to claim 1 and claim 9 are executed by calculation through a computer program.

[0089] In this embodiment, the uniformity ratio of the associated image is optimized by using the linear method and the shearing iteration method, and the unevenness of the projected image before and after calibration is reduced from 18.5% to 1.39%, thereby obtaining a color consistency correction effect with the same accuracy as when the image is not saturated, thereby improving the accuracy of inspection and proofreading.

[0090] The above embodiments can be implemented in whole or in part by software, hardware, firmware or any other combination. When implemented using software, the above embodiments can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions or computer programs. When the computer instructions or computer programs are loaded or executed on a computer, the process or function described in the embodiment of the present application is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. The computer instructions can be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions can be transmitted from one website site, computer, server or data center to another website site, computer, server or data center by wired (e.g., infrared, wireless, microwave, etc.). The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that contains one or more available media sets. The available medium can be a magnetic medium (e.g., a floppy disk, a hard disk, a tape), an optical medium (e.g., a DVD), or a semiconductor medium. The semiconductor medium can be a solid-state hard disk.

[0091] Those of ordinary skill in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0092] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0093] In the several embodiments provided in the present application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0094] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, and may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0095] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0096] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application can be essentially or partly embodied in the form of a software product that contributes to the prior art. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the methods described in each embodiment of the present application. The aforementioned storage medium includes: various media that can store program codes, such as USB flash drives, mobile hard disks, read-only memories (ROM), random access memories (RAM), magnetic disks or optical disks.

[0097] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

[0098] Finally: The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

[0099] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for testing color consistency of multiple projectors, characterized by: The testing method includes: S1, collecting the optical color intensity values ​​of a single projector respectively; S2, collecting the positioning positions of several projectors, correlating the color intensity values, calculating the common brightness response interval of several projectors, and recording the interval results in the form of translation templates and attenuation templates; S3, extracting the color block feature image of the common brightness range of the projector, and importing the color block features extracted from the effective area into the RGB color channel color block; Extract the data from the color block features and calculate the area deformation feature coefficient XZ; S4, calculate the average brightness Y of the color block feature according to the area deformation feature coefficient XZ c ; Obtain the brightness distribution of the color block feature and the average brightness L of the projected color block feature c , to the projection area and the single camera image of the projector, back to the single pixel mapping relationship, convert the curved surface projection into a plane projection, and calibrate it through the existing plane projection color.

2. The method for color consistency inspection of multiple projectors according to claim 1, characterized in that: The S1 step includes: 1) Confirm the single projector and the projection angle value, projection distance, obtain the developed film projection ratio, and collect the ambient brightness and projection image size value; 2) Obtain the projection ratio of the developed film, and then obtain the image width value and resolution value; 3) According to the image width value and the resolution value, the color intensity value is obtained using ANSI lumens as the unit of projection brightness.

3. The method for color consistency inspection of multiple projectors according to claim 2, characterized in that: The S2 step includes: 1) Obtain the positioning position values ​​of several projectors, and it is recommended to project a three-dimensional model to display the positioning position in the curved projection model; 2) Obtain the color intensity values ​​associated with the positioning position values ​​of several projectors, and calculate the common brightness corresponding interval coefficient KX of the several projectors; 3) The common brightness corresponding interval coefficient KX is associated with the preset translation template and attenuation template, and the area deformation characteristic coefficient XZ is obtained in the surface projection model.

4. The method for color consistency inspection of multiple projectors according to claim 3, characterized in that: The common loudness corresponding interval coefficient KX is obtained by the following formula: Wherein S1 identifies the positioning distance ratio of the first projector; S2 identifies the positioning distance ratio of the first projector; S3 identifies the positioning distance ratio of the first projector, where d1 / d2 / d3 represents the brightness value of a single projector; l represents the resolution value.

5. The method for color consistency inspection of multiple projectors according to claim 4, characterized in that: The deformation characteristic coefficient XZ is composed of a family of curves in two orthogonal directions, which is expressed as: in is the ith u line, V i k is the jth v line, is the network point, and the entire network is recorded as M k , k indicates the number of subdivisions; construct 4-point interpolation subdivision curves along the u / v directions to encrypt the mesh and maintain the geometric shape characteristics of the mesh; Among them, a is the tension parameter.

6. The method for color consistency inspection of multiple projectors according to claim 5, characterized in that: The average brightness L c Obtained by the following formula: The projector projects a picture with a brightness distribution of y im The uniform grayscale image of (x1, y1) is collected by the camera, output and calculated to obtain its brightness distribution y out (x m ,y m ); The brightness channel response function of the projector camera lens satisfies monotonic reversibility and is unrelated to the chromaticity channel. Therefore, according to the camera response function, c By out (x m ,y m )The brightness uniformity distribution of the image reflected by the screen can be obtained through inverse calculation.

7. The method for color consistency inspection of multiple projectors according to claim 6, characterized in that: The L c The average brightness value L0 of (xi,yi) is the correction target value, and the brightness uniformity distribution of the target real image is obtained as follows: And, the associated projector response function f p , and obtain the uniform ratio of the image in the figure.

8. The method for color consistency inspection of multiple projectors according to claim 7, characterized in that: The calibration in step S4 includes image saturation calibration. When the calibration image is not saturated or the saturated area is small, the processing results of the two methods are consistent; As the saturated area increases, the image is corrected by shearing; Through the linear method and the shearing iteration method, the uniformity ratio of the associated image is optimized, and the unevenness of the projection image before and after calibration is reduced from 18.5% to 1.39%, obtaining the color consistency correction effect with the same accuracy when the image is not saturated.

9. The method for color consistency inspection of multiple projectors according to claim 8, characterized in that: The developed film projection ratio includes the green-sensitive layer, red-sensitive layer, and blue-sensitive layer in the film, which contain magenta dye, cyan dye, and yellow dye respectively. The concentration of the three dyes controls the spectral transmittance of the film.

10. The method for color consistency inspection of multiple projectors according to claim 9, characterized in that: The method is tested by a spectrophotometer and color calibration software, and the steps of the color consistency testing method of multiple projectors according to claim 1 and claim 9 are executed by calculation through a computer program.

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