CN116866537A - Projection image distortion correction method and projection system based on corner detection - Google Patents
Projection image distortion correction method and projection system based on corner detection Download PDFInfo
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N9/00—Details of colour television systems
- H04N9/12—Picture reproducers
- H04N9/31—Projection devices for colour picture display, e.g. using electronic spatial light modulators [ESLM]
- H04N9/3179—Video signal processing therefor
- H04N9/3185—Geometric adjustment, e.g. keystone or convergence
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N9/00—Details of colour television systems
- H04N9/12—Picture reproducers
- H04N9/31—Projection devices for colour picture display, e.g. using electronic spatial light modulators [ESLM]
- H04N9/3141—Constructional details thereof
- H04N9/315—Modulator illumination systems
- H04N9/3161—Modulator illumination systems using laser light sources
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N9/00—Details of colour television systems
- H04N9/12—Picture reproducers
- H04N9/31—Projection devices for colour picture display, e.g. using electronic spatial light modulators [ESLM]
- H04N9/3179—Video signal processing therefor
- H04N9/3182—Colour adjustment, e.g. white balance, shading or gamut
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Abstract
The invention discloses a projection image distortion correction method and a projection system based on angular point detection, which are characterized in that a set checkerboard image is projected on a projection screen which is deformed, the projection image is shot, the checkerboard image is read from the projection image, the reference coordinates of control points are calculated, the environment where the projection image is positioned is judged to be a dark field or a bright field, a checkerboard color area is extracted, the screen contour is accurately found out through expansion corrosion, then the angular point coordinates are found through perspective transformation and reflection removal steps, the coordinate difference value between the angular point coordinates and the reference coordinates is calculated, gaussian function fitting is carried out on each row of coordinate difference value in a coordinate difference matrix to obtain a correction coordinate matrix, and the correction coordinate is written into a system chip and a display control chip, so that a laser television outputs corrected coordinates to finish distortion correction; based on the correction method of the invention, the projection device can display good images which are not distorted on the uneven projection screen, and a user does not need to replace a brand new projection screen.
Description
Technical Field
The invention belongs to the technical field of projection display, and particularly relates to a projection image distortion correction method and a projection system based on corner detection.
Background
The projection device projects the projection image onto the projection screen, but the projection screen may be physically deformed due to long-time use or external factors such as external force, and the initially flat receiving screen is changed into an uneven receiving screen; the projected image is displayed undistorted on a flat receiving screen, such as the checkered pattern shown in FIG. 1; on the deformed receiving screen, the original straight line is bent; for example, as shown in fig. 2, a standard checkered pattern is projected on an uneven receiving screen to become an irregular pattern, and the more serious the amplitude of the unevenness is, the more serious the distortion of the projected image is, thereby affecting the display effect of the projection apparatus.
Disclosure of Invention
The invention provides a projected image distortion correction method and a projection system based on corner detection aiming at the problem of projected image distortion caused by screen deformation, solves the problem of image distortion caused by the deformation of a projection screen, can realize the display of undistorted projection on the deformed projection screen, and can continuously use the deformed projection screen without influencing the viewing experience of a user.
The invention is realized by adopting the following technical scheme:
the utility model provides a projection image distortion correction method based on corner detection, which is applied to projection equipment and comprises the following steps:
projecting the checkerboard image onto a deformed projection screen, and obtaining a projection image;
calculating reference coordinates of corner points from the projection image based on the number of checkerboards;
recognizing the background brightness of the part of the projection image, which is removed from the checkerboard image, and converting the checkerboard image into a black-white checkerboard image by combining the background brightness to obtain a first projection image;
judging a projection screen frame based on the first projection image, and performing expansion corrosion and perspective transformation on the image in the projection screen frame to obtain a second projection image;
recognizing angular point coordinates of the second projection image, and calculating coordinate differences between the angular point coordinates and the reference coordinates to obtain a coordinate difference matrix;
fitting the coordinate difference value of each row in the coordinate difference matrix according to a Gaussian function model to obtain a corrected coordinate matrix and outputting the corrected coordinate matrix;
and controlling projection display of the projection device based on the correction coordinate matrix.
Summarizing some embodiments of the present invention, identifying corner coordinates of the second projection image, including;
searching internal corner coordinates: searching for angular point coordinates inside the second projection image by taking the first color in the checkerboard image as a reference, and searching for and complementing the internal angular point coordinates by taking the second image in the checkerboard image as a reference when the full angular point coordinates are not found by taking the first color as a reference;
complement vertex coordinates: based on projection display resolution, four vertex coordinates are complemented on the basis of the corner coordinates;
and (3) reflection treatment: when the coordinates of the full internal corner are not found based on the first color and the second color respectively, the method comprises the following steps: replacing the light reflecting part by using the same part of the pre-stored checkerboard image and updating the second projection image; and returning to the step of searching the coordinates of the internal corner points.
A projection system is provided, which comprises a projection device, a projection screen and a shooting terminal; the projection apparatus includes:
a projection unit for projecting the checkerboard image onto a deformed projection screen; the shooting terminal acquires a projection image and sends the projection image to the projection equipment;
a correction unit for calculating reference coordinates of control points from the projection image based on the number of checkerboards; recognizing the background brightness of the part of the projection image, which is removed from the checkerboard image, and converting the checkerboard image into a black-white checkerboard image by combining the background brightness to obtain a first projection image; judging a projection screen frame based on the first projection image, and performing expansion corrosion and perspective transformation on the image in the projection screen frame to obtain a second projection image; recognizing angular point coordinates of the second projection image, and calculating coordinate differences between the angular point coordinates and the reference coordinates to obtain a coordinate difference matrix; fitting the coordinate difference value of each row in the coordinate difference matrix according to a Gaussian function model to obtain a corrected coordinate matrix and outputting the corrected coordinate matrix;
the projection unit is used for controlling projection display of the projection device based on the correction coordinate matrix.
In some embodiments of the present invention, the correction unit, when identifying the coordinates of the corner points of the second projection image, includes:
searching internal corner coordinates: searching for angular point coordinates inside the second projection image by taking the first color in the checkerboard image as a reference, and searching for and complementing the internal angular point coordinates by taking the second image in the checkerboard image as a reference when the full angular point coordinates are not found by taking the first color as a reference;
complement vertex coordinates: based on projection display resolution, four vertex coordinates are complemented on the basis of the corner coordinates;
and (3) reflection treatment: when the coordinates of the full internal corner are not found based on the first color and the second color respectively, the method comprises the following steps: replacing the light reflecting part by using the same part of the pre-stored checkerboard image and updating the second projection image; and returning to the step of searching the coordinates of the internal corner points.
Compared with the prior art, the invention has the advantages and positive effects that: in the projection image distortion correction method and the projection system based on angular point detection, a set checkerboard image is projected on a projection screen which is deformed, a projection image is shot, the checkerboard image is read from the projection image, the reference coordinates of control points are calculated, the environment where the projection image is positioned is judged to be a dark field or a bright field, a checkerboard color area is extracted, the screen contour is accurately found out through expansion corrosion, then the angular point coordinates are found through perspective transformation and reflection removal steps, the coordinate difference value between the angular point coordinates and the reference coordinates is calculated, gaussian function fitting is carried out on each row of coordinate difference value in a coordinate difference matrix, the line between two corrected angular points is ensured to be smoother, and finally corrected coordinate correction matrixes are output, and corrected coordinates are written into a system chip and a display control chip, so that the laser television outputs corrected coordinates, and distortion correction is completed; based on the correction method of the invention, a user can correct the distorted image generated by the deformed projection screen by shooting the checkerboard image projected to the deformed projection screen by using the shooting terminal, so that the projection device can display a good image which is not distorted on the uneven projection screen, the user can obtain a good viewing effect without replacing the brand new projection screen, and the user cost can be saved.
Other features and advantages of the present invention will become more apparent from the following detailed description of embodiments of the present invention, which is to be read in connection with the accompanying drawings.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for the description of the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
FIG. 1 is an example of a checkered pattern displayed on a flat receiving screen;
FIG. 2 is an example of a checkered pattern displayed on a deformed receiving screen;
FIG. 3 is a schematic diagram of a combined structure of a conventional laser projection device;
fig. 4 is a schematic step diagram of a method for correcting distortion of a projection image based on corner detection according to the present invention;
FIG. 5 is a schematic illustration of a correction in the present invention to redefine the 4 vertex coordinates of a projected image to be full but not exceeding the projection screen;
FIG. 6 is a schematic view of a first projection image extracted in step S5 of the present invention;
FIG. 7 is a schematic view of the screen contour extracted in step S6 of the present invention;
FIG. 8 is a schematic view of a projection image obtained after the processing of step S7 of the present invention;
fig. 9 is a schematic view of the internal corner points identified by step S8 of the present invention;
fig. 10 is a schematic system architecture of a projection system according to the present invention.
Detailed Description
The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
In the description of the present invention, it should be understood that the terms "center," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like indicate orientations or positional relationships based on the orientation or positional relationships shown in the drawings, merely to facilitate describing the present invention and simplify the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present invention.
In the description of the present invention, it should be noted that the terms "mounted," "connected," and "coupled" are to be construed broadly, as well as, for example, fixedly coupled, detachably coupled, or integrally coupled, unless otherwise specifically indicated and defined. The specific meaning of the above terms in the present invention will be understood in specific cases by those of ordinary skill in the art. In the description of the above embodiments, particular features, structures, materials, or characteristics may be combined in any suitable manner in any one or more embodiments or examples.
The terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature. In the description of the present invention, unless otherwise indicated, the meaning of "a plurality" is two or more.
According to the projected image distortion correction method based on corner detection, reference coordinates and corner coordinates of correction control points are calculated through reading checkerboard images of a projection screen, the position offset of the corner points of the projection image is obtained through calculating the coordinate difference value of the reference coordinates and the corner coordinates, so that the position offset of the correction control points is obtained, corrected coordinate data are transmitted to a processor in a control system, then the control system controls a DLP controller and finally transmitted to a DMD control panel, and a corrected undistorted projected image is formed.
The invention takes laser projection equipment as an example to explain the proposed projection image distortion correction method based on angular point detection, which comprises but is not limited to projection equipment such as ultra-short focal laser projection equipment, long focal laser projection equipment, common projector and the like; the structure of the existing laser projection equipment is shown in fig. 3, and the existing laser projection equipment mainly comprises a control system and a projection system, wherein the control system is mainly responsible for controlling the display of pictures, converting the displayed pictures into video signals and control signals and transmitting the video signals and the control signals to the projection system; the projection system, consisting essentially of DLP (Digital Light Processing), is an optical video processing technique that uses tiny digital switches to control the laser source, which converts the light of the laser source into digital signals in a laser projection device, and controls DMD (Digital Micromirror Device) the deflection angle, thereby forming a high quality image.
As shown in fig. 4, the distortion correction processing step includes:
s1: the checkerboard image is projected onto a deformed projection screen.
The checkerboard image used in the correction method is composed of two different colors, the selection principle is to select according to the hue values of the colors in an HSV space, the colors with hue values different from a threshold value are selected so as to be convenient for identification, for example, red green, blue yellow, black white, yellow purple and the like can be selected, and contrast colors such as cold-warm contrast, hue contrast, complementary color contrast and the like can be selected so as to be used for distortion correction; the value range of the checkerboard is set according to the projection display size, when the projection display size is larger, the number of the checkerboard of the projection chart is more, and when the projection display size is smaller, the number of the checkerboard can be reduced.
S2: a projection image is acquired.
And acquiring a checkerboard image photo projected onto the deformed projection screen by adopting a camera of the projection equipment, or acquiring a checkerboard image projected onto the deformed projection screen by shooting through a user terminal, and transmitting the shot projection image to the laser projection equipment.
S3: the reference coordinates of the corner points are calculated from the projection image based on the number of checkerboards.
The corner points are the intersection points of all lattices in the checkerboard image and are the control points for implementing correction.
And identifying the distance of the frame line segments of the projection screen according to the four vertexes, calculating the distance between the control points of each part according to the number of the checkerboard, calculating the reference coordinates of the control points after the distance is obtained, supplementing the coordinates of the starting point and the tail point, and obtaining the reference coordinates of the checkerboard of the complete projection image.
If the projection image of the laser projection device is paved with the whole projection screen, 4 vertex coordinates of the projection image do not need to be redefined; if the projected image exceeds the projection screen or does not cover the projection screen, the user-defined coordinates are input to perform geometric correction on the laser projection device, so that the projected image of the laser projection device covers the whole projection screen, as shown in fig. 5.
S4: the background brightness of the projection image excluding the checkerboard image portion is identified, and a bright field or a dark field is identified based on the background brightness.
The two color areas of the checkerboard are removed, the background brightness after the projection screen area is removed is identified, when the maximum value of the background brightness is less than or equal to 78 (HSV color space brightness value, range: 0-255), the dark field environment is identified, and when the maximum value of the background brightness is greater than 78, the bright field environment is identified.
S5: and converting the checkerboard image into black and white checkerboard images by combining the background brightness to obtain a first projection image.
Presetting a Value range of HSV (Hue, saturation, value) capable of identifying two colors, wherein the Value ranges of the two colors corresponding to a dark field and a bright field are different, and only the two colors within the preset range are identified as the specified two colors; taking a 5X10 red-green checkerboard projection image as an example, when red is identified, the gray value of the color is set to 255 (white), when green is identified, the gray value of the color is set to 0 (black), and the vertexes of white and black checkerboards are corner points, as shown in fig. 6, to identify black-white checkerboard images with distortion.
And S6, determining a projection screen frame based on the first projection image.
And extracting features of the projection image, extracting the contour edge of the projection screen, finding a center point, taking other edge information of the projection screen background into consideration, calculating the contour area containing the center by adopting a mode of circularly judging the distance between each extracted contour and the center point, determining the contour with the minimum area and containing the center point as the contour of the projection screen, and identifying the frame of the projection screen as shown in figure 7.
And S7, performing expansion corrosion and perspective transformation on the image in the frame of the projection screen to obtain a second projection image.
The image in the extracted projection screen outline is subjected to expansion corrosion and perspective transformation, as shown in fig. 8, all the checkerboard identified by the projection image is filled with white, the projection image is converted into a tiled image with a set size through perspective transformation, and finally the image is output, and four vertex coordinates are found for sorting.
S8: the corner coordinates of the second projection image are identified.
And removing four vertex coordinates of the screen contour, identifying a checkerboard, drawing the contour position by using a solid line, and finding out the coordinates of angular points inside the contour, wherein the black points in the figure are the actual coordinates of the angular points which are identified, as shown in fig. 9 (5X 10 checkerboard is an example).
Then, finding corner coordinates by using one of the two colors, if execution fails, replacing the other color repeatedly if all the corner coordinates are not found or not found, if the execution still fails, executing the light reflection processing of S10, and then repeating the step of identifying the corner coordinates in the outline; and finally, compensating corner coordinates at the four frames, and filling the vertex coordinates according to the coordinates at the four vertexes of the projection display resolution.
S9: and (5) carrying out light reflection treatment.
When the shot image is in a comparatively large environment, the laser projection equipment cannot completely identify the angular point coordinates of the checkerboard due to partial reflection, a prestored checkerboard reflection processing method is adopted for processing, and when the partial reflection is detected to be serious, the position image is replaced by the prestored checkerboard image to ensure that the angular point coordinates of the position can be identified.
S10: and calculating the coordinate difference between the angular point coordinates and the reference coordinates to obtain a coordinate difference matrix.
Setting a reference coordinate matrix as follows:
the angular point coordinate matrix identified based on the second projection image is:
the coordinate difference matrix is:
s11: fitting the coordinate differences of each row in the coordinate difference matrix according to a Gaussian function model to obtain a corrected coordinate matrix and outputting the corrected coordinate matrix.
The output correction coordinate difference is the recognized corner coordinate difference, and the number of recognized corners is far less than the number of pixels, so that the coordinate difference calculated by the corner detection cannot completely realize the correction of the whole distortion smoothness, and fine saw-tooth lines possibly appear when fine lines are displayed between two corners, and therefore the Gaussian function fitting step is added, the coordinate difference calculated by each row is fitted according to a Gaussian function model, so that the corrected display effect is smoother, and the projection display is prevented from generating fine saw-tooth distortion.
S12: the projection display of the projection device is controlled based on the corrected coordinate matrix.
And finally outputting the corrected coordinate matrix obtained in the step S12 as a distortion correction processing result.
Based on the above, the present invention further provides a projection system, as shown in fig. 10, including:
projection device 10, projection screen 11 and shooting terminal 12, wherein projection device 10 includes:
a projection unit 101 for projecting a checkerboard image onto a deformed projection screen 11; the photographing terminal 12 acquires the projection image and transmits it to the projection device 10.
A correction unit 102 for calculating reference coordinates of the control points from the projection image based on the number of checkerboards; recognizing background brightness of the checkerboard image part removed from the projection image, and converting the checkerboard image into black and white checkerboard images by combining the background brightness to obtain a first projection image; judging a projection screen frame based on the first projection image, and performing expansion corrosion and perspective transformation on the image in the projection screen frame to obtain a second projection image; recognizing angular point coordinates of the second projection image, and calculating coordinate differences between the angular point coordinates and the reference coordinates to obtain a coordinate difference matrix; fitting the coordinate difference value of each row in the coordinate difference matrix according to a Gaussian function model to obtain a corrected coordinate matrix and outputting the corrected coordinate matrix;
the projection unit 102 then controls the projection display of the projection device based on the corrected coordinate matrix.
Wherein the correction unit 102, when recognizing the coordinates of the corner points of the second projection image, performs the following steps:
1. searching internal corner coordinates: searching for angular point coordinates inside the second projection image by taking the first color in the checkerboard image as a reference, and searching for and complementing the internal angular point coordinates by taking the second image in the checkerboard image as a reference when the full angular point coordinates are not found by taking the first color as a reference;
2. complement vertex coordinates: based on projection display resolution, four vertex coordinates are complemented on the basis of the corner coordinates;
3. and (3) reflection treatment: when the coordinates of the full internal corner are not found based on the first color and the second color respectively, the method comprises the following steps: replacing the light reflecting part by using the same part of the pre-stored checkerboard image and updating a second projection image; and returning to the step of searching the coordinates of the internal corner points.
The correction method for displaying a good image on the deformed projection screen by the projection system is described in detail in the correction method given above, and will not be described here.
The projected image distortion correction method and the projection system based on the corner detection provided by the invention can be applied to the situation that the deformation of the projection screen of the laser projection equipment such as families, cinema, office places and the like generates picture distortion, the correction process can be automatically completed by only projecting one checkerboard image to identify the corner coordinates of the checkerboard image, the quantity of the corner can be set by itself, no requirement is required on a shooting terminal and a shooting distance, and the correction process is simple to operate and suitable for popularization.
It should be noted that, in the specific implementation process, the above method part may be implemented by executing, by a processor in a hardware form, computer execution instructions in a software form stored in a memory, which is not described herein, and the program corresponding to the executed action may be stored in a computer readable storage medium of the system in a software form, so that the processor invokes and executes the operations corresponding to the above modules.
The computer readable storage medium above may include volatile memory, such as random access memory; but may also include non-volatile memory such as read-only memory, flash memory, hard disk, or solid state disk; combinations of the above types of memories may also be included.
The processor referred to above may be a general term for a plurality of processing elements. For example, the processor may be a central processing unit, or may be other general purpose processors, digital signal processors, application specific integrated circuits, field programmable gate arrays or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, or the like. A general purpose processor may be a microprocessor or may be any conventional processor or the like, but may also be a special purpose processor.
It should be noted that the above description is not intended to limit the invention, but rather the invention is not limited to the above examples, and that variations, modifications, additions or substitutions within the spirit and scope of the invention will be within the scope of the invention.
Claims (4)
1. A projection image distortion correction method based on corner detection is applied to projection equipment and is characterized by comprising the following steps:
projecting the checkerboard image onto a deformed projection screen, and obtaining a projection image;
calculating reference coordinates of corner points from the projection image based on the number of checkerboards;
recognizing the background brightness of the part of the projection image, which is removed from the checkerboard image, and converting the checkerboard image into a black-white checkerboard image by combining the background brightness to obtain a first projection image;
judging a projection screen frame based on the first projection image, and performing expansion corrosion and perspective transformation on the image in the projection screen frame to obtain a second projection image;
recognizing angular point coordinates of the second projection image, and calculating coordinate differences between the angular point coordinates and the reference coordinates to obtain a coordinate difference matrix;
fitting the coordinate difference value of each row in the coordinate difference matrix according to a Gaussian function model to obtain a corrected coordinate matrix and outputting the corrected coordinate matrix;
and controlling projection display of the projection device based on the correction coordinate matrix.
2. The method for correcting distortion of a projected image based on corner detection according to claim 1, characterized in that identifying corner coordinates of the second projected image comprises;
searching internal corner coordinates: searching for angular point coordinates inside the second projection image by taking the first color in the checkerboard image as a reference, and searching for and complementing the internal angular point coordinates by taking the second image in the checkerboard image as a reference when the full angular point coordinates are not found by taking the first color as a reference;
complement vertex coordinates: based on projection display resolution, four vertex coordinates are complemented on the basis of the corner coordinates;
and (3) reflection treatment: when the coordinates of the full internal corner are not found based on the first color and the second color respectively, the method comprises the following steps: replacing the light reflecting part by using the same part of the pre-stored checkerboard image and updating the second projection image; and returning to the step of searching the coordinates of the internal corner points.
3. A projection system comprising a projection device, a projection screen and a shooting terminal, characterized in that the projection device comprises:
a projection unit for projecting the checkerboard image onto a deformed projection screen; the shooting terminal acquires a projection image and sends the projection image to the projection equipment;
a correction unit for calculating reference coordinates of control points from the projection image based on the number of checkerboards; recognizing the background brightness of the part of the projection image, which is removed from the checkerboard image, and converting the checkerboard image into a black-white checkerboard image by combining the background brightness to obtain a first projection image; judging a projection screen frame based on the first projection image, and performing expansion corrosion and perspective transformation on the image in the projection screen frame to obtain a second projection image; recognizing angular point coordinates of the second projection image, and calculating coordinate differences between the angular point coordinates and the reference coordinates to obtain a coordinate difference matrix; fitting the coordinate difference value of each row in the coordinate difference matrix according to a Gaussian function model to obtain a corrected coordinate matrix and outputting the corrected coordinate matrix;
the projection unit controls projection display of the projection device based on the correction coordinate matrix.
4. A projection system according to claim 3, wherein the correction unit, when identifying the corner coordinates of the second projection image, comprises:
searching internal corner coordinates: searching for angular point coordinates inside the second projection image by taking the first color in the checkerboard image as a reference, and searching for and complementing the internal angular point coordinates by taking the second image in the checkerboard image as a reference when the full angular point coordinates are not found by taking the first color as a reference;
complement vertex coordinates: based on projection display resolution, four vertex coordinates are complemented on the basis of the corner coordinates;
and (3) reflection treatment: when the coordinates of the full internal corner are not found based on the first color and the second color respectively, the method comprises the following steps: replacing the light reflecting part by using the same part of the pre-stored checkerboard image and updating the second projection image; and returning to the step of searching the coordinates of the internal corner points.
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN117523025A (en) * | 2024-01-05 | 2024-02-06 | 之江实验室 | Digital imitation generation method based on light intensity distribution adjustment |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN117523025A (en) * | 2024-01-05 | 2024-02-06 | 之江实验室 | Digital imitation generation method based on light intensity distribution adjustment |
| CN117523025B (en) * | 2024-01-05 | 2024-05-10 | 之江实验室 | Digital imitation generation method based on light intensity distribution adjustment |
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