CN113014896B

CN113014896B - Projection image correction method, projection device and system

Info

Publication number: CN113014896B
Application number: CN201911320662.6A
Authority: CN
Inventors: 李泽广; 吴超
Original assignee: Qingdao Hisense Laser Display Co Ltd
Current assignee: Qingdao Hisense Laser Display Co Ltd
Priority date: 2019-12-19
Filing date: 2019-12-19
Publication date: 2023-02-07
Anticipated expiration: 2039-12-19
Also published as: CN113014896A

Abstract

The application discloses a projected image correction method, a projection device and a projection system, and belongs to the field of projection display. The method comprises the following steps: in response to the correction instruction, the first projection image is projected and displayed, and the second projection device is instructed to project and display the second projection image; acquiring a shot image obtained by shooting the first projection image and the second projection image by the camera; and if the area of the overlapping region of the first mark graph and the second mark graph in the shot image is smaller than the area threshold value, adjusting the projection position of the target projection image until the area of the overlapping region of the first mark graph and the second mark graph is larger than or equal to the area threshold value. Due to the fact that the projection position of the target projection image can be adjusted based on the shot image shot by the camera, the efficiency and the reliability of projection image correction are improved, and meanwhile seamless splicing of adjacent projection images is guaranteed.

Description

Projection image correction method, projection device and system

Technical Field

The present disclosure relates to the field of projection display, and in particular, to a method, a projection device, and a system for correcting a projection image.

Background

The projection system may include a plurality of projection devices arranged in an array, and a computer coupled to each projection device. The computer can control each projection device to project and display one projection image, overlapping areas exist in every two adjacent projection images, and the plurality of projection images can be spliced into a complete picture.

In the related art, if the overlapping areas of two adjacent projection images are not completely overlapped, a worker needs to manually adjust the projection position of the projection image projected and displayed by any one of the two adjacent projection devices through the computer, so that the overlapping areas of the two adjacent projection images are completely overlapped, and the projection images of the two adjacent projection devices are seamlessly spliced.

However, the correction of the projected image is inefficient because a worker is required to manually correct the projected image.

Disclosure of Invention

The embodiment of the disclosure provides a projected image correction method, a projection device and a projection system, which can solve the problem of low efficiency of projected image correction in the related art. The technical scheme is as follows:

in one aspect, a method for correcting a projection image is provided, and is applied to a first projection device in a projection system, where the projection system further includes: a second projection device arranged adjacent to the first projection device, and a camera; the method comprises the following steps:

in response to a correction instruction, a first projection image is projected and displayed, and the second projection device is instructed to project and display a second projection image, wherein a first edge overlapping area of the first projection image displays a first mark figure, and a second edge overlapping area of the second projection image displays a second mark figure, wherein the first edge overlapping area and the second edge overlapping area are the same in size, and the display position of the first mark figure in the first edge overlapping area is the same as the display position of the second mark figure in the second edge overlapping area;

acquiring a shot image obtained by shooting the first projection image and the second projection image by the camera;

if the area of the overlapping area of the first mark figure and the second mark figure in the shot image is smaller than an area threshold value, adjusting the projection position of a target projection image until the area of the overlapping area of the first mark figure and the second mark figure is larger than or equal to the area threshold value;

wherein the target projection image includes at least one of the first projection image and the second projection image.

In another aspect, a projection system is provided, the projection system comprising a first projection device and a second projection device arranged adjacently, and a camera;

the first projection device is used for responding to a correction instruction, projecting and displaying a first projection image, and sending a projection instruction to the second projection device, wherein a first edge overlapping area of the first projection image displays a first mark graph;

the second projection device is used for responding to the projection instruction, and projecting and displaying a second projection image, wherein a second edge overlapping area of the second projection image displays a second mark figure, the size of the first edge overlapping area is the same as that of the second edge overlapping area, and the display position of the first mark figure in the first edge overlapping area is the same as that of the second mark figure in the second edge overlapping area;

the camera is used for shooting the first projection image and the second projection image to obtain a shot image, and sending the shot image to the first projection equipment;

the first projection device is further used for adjusting the projection position of the target projection image when the area of the overlapping area of the first mark figure and the second mark figure in the shot image is determined to be smaller than an area threshold value, until the area of the overlapping area of the first mark figure and the second mark figure is larger than or equal to the area threshold value; wherein the target projection image includes at least one of the first projection image and the second projection image.

In yet another aspect, a projection apparatus is provided, the projection apparatus comprising: the device comprises a light source, a light valve, a projection lens and a processor;

the light source is used for emitting light of a plurality of different colors;

the light valve is used for modulating each color of light into an image beam and transmitting the image beam to the projection lens;

the projection lens is used for projecting the image light beam to a projection screen;

the processor is configured to implement the method of correcting a projected image as described in the above aspect.

In still another aspect, there is provided a computer-readable storage medium having instructions stored therein, which when run on a computer, cause the computer to perform the method of correcting a projected image according to the above aspect.

The beneficial effects brought by the technical scheme provided by the embodiment of the disclosure at least comprise:

the embodiment of the disclosure provides a method, a projection device and a system for correcting a projection image, wherein the correction method can shoot a first projection image projected and displayed by a first projection device and a second projection image projected and displayed by a second projection device to obtain a shot image. And when the area of the overlapping region of the first marker pattern and the second marker pattern in the shot image is determined to be smaller than the area threshold, adjusting the projection position of the target projection image until the area of the overlapping region of the first marker pattern and the second marker pattern is larger than or equal to the area threshold. The projection position of the target projection image can be adjusted based on the shot image shot by the camera, and workers do not need to manually adjust the projection position of the projection image, so that the efficiency and the reliability of projection image correction are improved, and meanwhile, seamless splicing of adjacent projection images is ensured.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present disclosure, and it is obvious for those skilled in the art to obtain other drawings based on the drawings without creative efforts.

Fig. 1 is a schematic structural diagram of a projection system provided in an embodiment of the present disclosure;

FIG. 2 is a flowchart of a method for correcting a projected image according to an embodiment of the disclosure;

FIG. 3 is a schematic diagram of a first projected image provided by an embodiment of the present disclosure;

FIG. 4 is a schematic diagram of a second projection image provided by an embodiment of the present disclosure;

FIG. 5 is a schematic diagram of a captured image provided by an embodiment of the present disclosure;

FIG. 6 is a flowchart of another method for correcting a projected image provided by an embodiment of the present disclosure;

FIG. 7 is a schematic illustration of a first marker pattern and a second marker pattern provided by an embodiment of the present disclosure;

FIG. 8 is a schematic illustration of another first marker pattern and a second marker pattern provided by embodiments of the present disclosure;

FIG. 9 is a schematic illustration of yet another first and second pattern of markings provided by an embodiment of the present disclosure;

FIG. 10 is a schematic diagram of a display of multiple marker patterns per projected image provided by an embodiment of the present disclosure;

FIG. 11 is a schematic diagram of another embodiment of the present disclosure that displays multiple marker patterns per projection image;

fig. 12 is a schematic structural diagram of a projection apparatus provided in an embodiment of the present disclosure.

Detailed Description

To make the objects, technical solutions and advantages of the present disclosure more apparent, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings.

Fig. 1 is a schematic structural diagram of a projection system provided in an embodiment of the present disclosure. As shown in fig. 1, the projection system may include a first projection device 110 and a second projection device 120 arranged adjacently, and a camera 130. The first projection device 110 may be connected to the second projection device 120, and the camera 130 may be disposed on the light exit side of the first projection device 110.

Optionally, the projection system may include a plurality of projection devices arranged in an array, fig. 1 only shows two projection devices, and the number of projection devices provided in the projection system is not limited in the embodiment of the disclosure. And the projection device may be a laser projection device, a bulb projection device, or a Light Emitting Diode (LED) projection device.

Fig. 2 is a flowchart of a method for correcting a projection image according to an embodiment of the present disclosure, which may be applied to the first projection device 110 in the projection system shown in fig. 1, and the projection system may further include a second projection device 120 arranged adjacent to the first projection device 110, and a camera 130. As shown in fig. 2, the method may include:

step 201, responding to the correction instruction, the first projection image is projected and displayed, and the second projection device is instructed to project and display the second projection image.

In the embodiment of the disclosure, the correction instruction may be triggered by a user through a remote controller, and after receiving the correction instruction sent by the remote controller, the first projection device may display the first projection image in a projection manner in response to the correction instruction, and send a projection instruction to the second projection device. Or, a correction button may be disposed on the first projection device, and the first projection device may generate a correction instruction after detecting a click operation of a user on the correction button, and may further display the first projection image by projection in response to the correction instruction, and send the projection instruction to the second projection device. Still alternatively, the first projection device may periodically generate a correction instruction, and may project and display the first projection image and transmit the projection instruction to the second projection device in response to the correction instruction.

Alternatively, the first projection image, the second projection image, the first edge overlapping area, and the second edge overlapping area may all be polygons. For example, they may all be rectangular. Referring to fig. 3 and 4, the first edge overlapping region 141 of the first projection image 140 is displayed with a first marker graphic 142, and the second edge overlapping region 151 of the second projection image 150 is displayed with a second marker graphic 152.

The first edge overlap region 141 is a region of the first projection image that needs to overlap the second projection image 150, and the second edge overlap region 151 is a region of the second projection image that needs to overlap the first projection image 140. The first edge overlapping area 141 and the second edge overlapping area 151 have the same size, and the display position of the first mark figure 142 in the first edge overlapping area 141 is the same as the display position of the second mark figure 152 in the second edge overlapping area 151.

Illustratively, the first mark pattern 142 is positioned at the left top corner of the first edge overlap region 141, and the second mark pattern 152 is positioned at the left top corner of the second edge overlap region 151.

Alternatively, the area of the first edge overlap region may be a fixed percentage of the area of the first projected image and the area of the second edge overlap region may be a fixed percentage of the area of the second projected image. Illustratively, the fixed percentage may be 20%. The first and second marker patterns may both be polygonal patterns, for example both may be cross patterns, or both may be quadrilateral patterns.

Step 202, acquiring a shot image obtained by shooting the first projection image and the second projection image by the camera.

Referring to fig. 5, the camera may photograph the first and

second projection images

140 and 150 to obtain a photographed image 160, and then may transmit the photographed image 160 to the first projection apparatus.

Optionally, the shooting range of the camera is larger than the projection range of the first projection device, so that the camera can shoot the first edge overlapping region of the first projection image and the second edge overlapping region of the second projection image.

Step 203, detecting whether the area of the overlapping area of the first mark pattern and the second mark pattern in the shot image is smaller than an area threshold value.

After receiving the shot image sent by the camera, the first projection device can calculate the area of the overlapping area of the first mark pattern and the second mark pattern in the shot image and detect whether the area of the overlapping area is smaller than an area threshold value. If the area of the overlapped area is smaller than the area threshold, which indicates that the overlapped area of the first edge overlapped area of the first projection image and the second edge overlapped area of the second projection image is small and the overlapped degree of the two does not meet the requirement of the tiled display, step 204 may be executed. If the area of the overlapping area is larger than or equal to the area threshold, it indicates that the overlapping area of the first edge overlapping area of the first projection image and the second edge overlapping area of the second projection image is larger, and the overlapping degree of the two satisfies the requirement of the mosaic display, the process is ended.

And step 204, adjusting the projection position of the target projection image.

The first projection device may adjust the projection position of the target projection image when determining that the area of the overlapping region is smaller than the area threshold, and then execute step 203 again until the area of the overlapping region of the first mark pattern and the second mark pattern is greater than or equal to the area threshold, and then end the process.

Wherein the area threshold may be a fixed value pre-stored in the first projection device. And the area threshold may be determined based on the area of the smaller of the first and second marker patterns, for example, the area threshold may be 90%, 95%, or 100% of the area of the smaller of the first and second marker patterns. The target projection image may include at least one of the first projection image and the second projection image.

In summary, the present disclosure provides a method for correcting a projection image, where the method for correcting a projection image may capture a first projection image projected and displayed by a first projection device and a second projection image projected and displayed by a second projection device, so as to obtain a captured image. And when the area of the overlapping area of the first mark figure and the second mark figure in the shot image is determined to be smaller than the area threshold, adjusting the projection position of the target projection image until the area of the overlapping area of the first mark figure and the second mark figure is larger than or equal to the area threshold. The projection position of the target projection image can be adjusted based on the shot image shot by the camera, and the projection position of the projection image does not need to be manually adjusted by a worker, so that the efficiency and the reliability of projection image correction are improved, and meanwhile, seamless splicing of adjacent projection images is ensured.

Fig. 6 is a flowchart of another method for correcting a projected image according to an embodiment of the present disclosure. The method for correcting the projected image may be applied to the first projection device 110 in the projection system shown in fig. 1, and the projection system may further include a second projection device 120 arranged adjacent to the first projection device 110, and a camera 130. As shown in fig. 6, the method may include:

step 601, responding to the correction instruction, and displaying the first projection image in a projection mode, and instructing a second projection device to display a second projection image in a projection mode.

In the embodiment of the disclosure, the correction instruction may be triggered by a user through a remote controller, and the first projection device may, after receiving the correction instruction sent by the remote controller, display the first projection image by projection in response to the correction instruction, and send the projection instruction to the second projection device. Or, a correction button may be disposed on the first projection device, and the first projection device may generate a correction instruction after detecting a click operation of a user on the correction button, and may further display the first projection image by projection in response to the correction instruction, and send the projection instruction to the second projection device. Still alternatively, the first projection device may periodically generate a correction instruction, and may project and display the first projection image and send a projection instruction to the second projection device in response to the correction instruction.

Alternatively, the first projection image, the second projection image, the first edge overlapping area, and the second edge overlapping area may all be polygons. For example, they may all be rectangular. Referring to fig. 3 and 4, the first edge overlapping area 141 of the first projection image 140 is displayed with a first marker graphic 142, and the second edge overlapping area 151 of the second projection image 150 is displayed with a second marker graphic 152.

The first edge overlap region 141 is a region of the first projection image that needs to overlap the second projection image 150, and the second edge overlap region 151 is a region of the second projection image that needs to overlap the first projection image 140. The first edge overlapping area 141 and the second edge overlapping area 151 have the same size, and the display position of the first mark figure 142 in the first edge overlapping area 141 is the same as the display position of the second mark figure 152 in the second edge overlapping area 151. Illustratively, the first mark pattern 142 is positioned at the left top corner of the first edge overlapping region 141, and the second mark pattern 152 is positioned at the left top corner of the second edge overlapping region 151.

Alternatively, the area of the first edge overlap region may be a fixed percentage of the area of the first projected image and the area of the second edge overlap region may be a fixed percentage of the area of the second projected image. Illustratively, the fixed percentage may be 20%. The first and second marker patterns may both be polygonal patterns, for example may both be cross patterns, or may both be quadrilateral patterns.

The first projection image and the second projection image may have the same size or different sizes, and the first projection image and the second projection image may have the same shape or different shapes. The first and second mark patterns may be the same size or different sizes. The first mark pattern and the second mark pattern may be the same in shape or different in shape, which is not limited in this disclosure.

Step 602, acquiring a shot image obtained by shooting the first projection image and the second projection image by the camera.

After the first projection device projects and displays the first projection image and instructs the second projection device to project and display the second projection image, referring to fig. 5, the camera may capture the first projection image 140 and the second projection image 150 to obtain a captured image 160, and then may transmit the captured image 160 to the first projection device.

In the embodiment of the present disclosure, the shooting range of the camera is larger than the projection range of the first projection device, so that the camera can be ensured to shoot the first edge overlapping region of the first projection image and the second edge overlapping region of the second projection image.

Optionally, a processor may be disposed in the first projection device, and the camera may convert the captured image into a digital signal after obtaining the captured image, and send the digital signal to the processor in the first projection device.

Step 603, detecting whether the area of the overlapping area of the first mark pattern and the second mark pattern in the shot image is smaller than an area threshold value.

After the first projection device acquires the shot image sent by the camera, the area of the overlapping area of the first mark pattern and the second mark pattern in the shot image can be calculated, and whether the area of the overlapping area is smaller than an area threshold value or not can be detected. If the area of the overlapped area is smaller than the area threshold, which indicates that the overlapped area of the first edge overlapped area of the first projection image and the second edge overlapped area of the second projection image is small and the overlapped degree of the two does not meet the requirement of the tiled display, step 604 may be executed. If the area of the overlapping area is larger than or equal to the area threshold, it indicates that the overlapping area of the first edge overlapping area of the first projection image and the second edge overlapping area of the second projection image is large, the overlapping degree of the first edge overlapping area and the second edge overlapping area of the second projection image meets the requirements of tiled display, and the first projection device does not need to adjust the projection position of the target projection image, and then the process is ended.

The area threshold may be a fixed value pre-stored in the first projection device. And the area threshold may be determined based on the area of the smaller of the first and second marker patterns, for example, the area threshold may be 90%, 95%, or 100% of the area of the smaller of the first and second marker patterns.

And step 604, detecting whether the number of pixels between the central point of the first mark pattern and the central point of the second mark pattern is larger than a number threshold value.

The first projection device stores a number threshold in advance, after it is determined that the area of the overlapping region of the first marker pattern and the second marker pattern is smaller than the area threshold, it may be detected whether the number of pixels between the center point of the first marker pattern and the center point of the second marker pattern is greater than the number threshold, and if the number of pixels is greater than the number threshold, it indicates that the overlapping region of the center point of the first marker pattern in the first projection image and the center point of the second marker pattern in the second projection image is small, and the overlapping degree of the two does not meet the requirement of the tiled display, step 605 may be executed. If the number of the pixels is less than or equal to the number threshold, it indicates that the overlapping area between the central point of the first marker pattern in the first projection image and the central point of the second marker pattern in the second projection image is large, and the overlapping degree of the two meets the requirement of the mosaic display, step 606 may be executed.

In an embodiment of the present application, each of the marker patterns may be a symmetric image, and the center point of each of the marker patterns may be a geometric center of the marker pattern. For example, each of the mark patterns may be a central symmetrical pattern, and the center point of each of the mark patterns may be a symmetrical center of the central symmetrical pattern.

Referring to fig. 7 and 8, the first projection apparatus may first determine a length L of a connection line between the center point O1 of the first mark pattern 142 and the center point O2 of the second mark pattern 152 in the photographed image. Then, the number of pixels d between the center point O1 of the first mark pattern 142 and the center point O2 of the second mark pattern 152 is determined based on the connection length L and the fixed ratio K.

Wherein the fixed ratio K is a ratio of the number M of pixels per column (i.e. the number of pixel rows) to the length d1 of the projection image in the pixel column direction in each projection image, and the fixed ratio K is the ratio of the number M of pixels per column to the length d1 of the projection image in the pixel column direction

Alternatively, the fixed ratio K may be a ratio of the number N of pixels per row (i.e., the number of pixel columns) to the length d2 of the projection image in the pixel column direction

M is a positive integer greater than 1, and N is a positive integer greater than 1.

For example, assuming that the resolution of each projection image is 1920 × 1080, that is, M is 1920 and N is 1080, the resolution is

Or

And step 605, translating the projection position of the target projection image. Step 604 is performed.

In the embodiment of the present disclosure, when it is determined that the number of pixels between the center point of the first marker pattern and the center point of the second marker pattern is greater than the number threshold, the first projection device may translate the projection position of the target projection image, and then may perform step 604 again, until the number of pixels between the center point of the first marker pattern and the center point of the second marker pattern is less than or equal to the number threshold, and then perform step 606.

Wherein the target projection image may comprise at least one of the first projection image and the second projection image. If the target projection image is a first projection image, the first projection device may translate a projection position of the first projection image. If the target projection image is a second projection image, the first projection device may translate a projection position of the second projection image.

Taking the target projection image as the first projection image as an example, referring to fig. 7 and 8, in the process of translating the projection position of the first projection image, the first projection device may translate the pixels in the first projection image by d pixels toward the direction close to the second marker pattern 152 along the connection line between the center point O1 of the first marker pattern 142 and the center point O2 of the second marker pattern 152, thereby adjusting the projection position of the first projection image.

Alternatively, the first projection device may translate the pixels in the first projection image a first number d3 of pixels in a first direction adjacent the second marker pattern 152 and a second number d4 of pixels in a second direction adjacent the second marker pattern 152. The first direction is parallel to one side of the first projection image, and the second direction is parallel to the other side of the first projection image. The first number of pixels d3 and the second number of pixels d4 may satisfy:

if the target projection image includes a first projection image and a second projection image, the first projection device may respectively translate a projection position of the first projection image and a projection position of the second projection image.

Referring to fig. 7 and 8, the first projection apparatus may translate the pixels in the first projection image by d/2 pixels toward the second marker pattern 152 along a connection line between the center point O1 of the first marker pattern 142 and the center point O2 of the second marker pattern 152 in the process of translating the projection position of the first projection image and the projection position of the second projection image, respectively. Meanwhile, along a connecting line between the center point O1 of the first marker graphic 142 and the center point O2 of the second marker graphic 152, the pixels in the second projection image are translated by d/2 pixels toward the direction close to the first marker graphic 142, thereby realizing the adjustment of the projection position of the first projection image and the projection position of the second projection image.

Step 606, detecting whether an included angle between a first axis of the first mark pattern and a second axis of the second mark pattern is larger than an angle threshold value.

After the first projection device determines that the number of pixels between the center point of the first mark pattern and the center point of the second mark pattern is smaller than or equal to the number threshold, an included angle between a first axis of the first mark pattern and a second axis of the second mark pattern in the shot image can be determined, and whether the included angle between the first axis and the second axis is larger than the angle threshold or not is detected. If the included angle between the first axis and the second axis is greater than the angle threshold, it indicates that the overlapping degree of the first marker pattern in the first projection image and the second marker pattern in the second projection image does not meet the requirement of the tiled display, step 607 is executed. If the included angle between the first axis and the second axis is smaller than or equal to the angle threshold, indicating that the overlapping degree of the first mark pattern in the first projection image and the second mark pattern in the second projection image meets the requirements of splicing display, then the projection position of the first projection image is not rotated, and the process is ended.

Alternatively, the first and second marker patterns may both be cross patterns. The first axis may be a horizontal line of the first marking pattern and the second axis is a horizontal line of the second marking pattern.

Referring to fig. 5 and 7, the first axis is parallel to the first side of the first edge overlapping region 141, the second axis is parallel to the first side of the second edge overlapping region 151, each of the edge overlapping regions may be rectangular, and the first side of each of the edge overlapping regions may be parallel to the pixel row direction or the pixel column direction of the edge overlapping region. I.e. the first axis is parallel to the second axis. And the included angle between the first axis and the second axis is less than or equal to the angle threshold. Referring to fig. 8 and 9, the first axis is not parallel to the second axis, and the first axis and the second axis are at an angle greater than an angular threshold.

Optionally, after determining that the number of pixels between the center point of the first mark pattern and the center point of the second mark pattern is less than or equal to the number threshold, the first projection device may directly measure the included angle between the first axis and the second axis. Alternatively, the first projection device may determine a connection line between the center point of the first marker pattern and the center point of the second marker pattern while determining the number of pixels between the center point of the first marker pattern and the center point of the second marker pattern in the captured image. And respectively determine a first angle between the line and the horizontal line of the first marking pattern and a second angle between the line and the horizontal line of the second marking pattern 152, both the first angle and the second angle being less than 90 degrees). And then determining the absolute value of the difference value between the first included angle and the second included angle as the included angle between the first axis and the second axis.

Step 607, the projection position of the target projection image is rotated. Step 606 is performed.

In this disclosure, after determining that the included angle between the first axis and the second axis is greater than the angle threshold, the first projection device may rotate the projection position of the target projection image, and then may execute step 606 again until the included angle between the first axis and the second axis is less than or equal to the angle threshold, and then the process ends.

If the target projection image is a first projection image, the first projection device may rotate a projection position of the first projection image. If the target projection image is a second projection image, the first projection device may rotate a projection position of the second projection image.

Taking the target projection image as the first projection image, the first included angle is α, the second included angle is β, and referring to fig. 8, since the first included angle α is greater than the second included angle β, the first projection device may rotate the first mark pattern in the first projection image clockwise by α - β. Referring to fig. 9, since the first included angle α is smaller than the second included angle β, the first marker graphic 142 in the first projection image is rotated counterclockwise by β - α.

If the target projection image includes a first projection image and a second projection image, the first projection device may rotate a projection position of the first projection image and a projection position of the second projection image, respectively.

For example, referring to fig. 8, the first projection device 110 may rotate the first marker graphic 142 in the first projection image 140 clockwise by (α - β)/2 and rotate the second marker graphic 152 in the second projection image 150 counterclockwise by (α - β)/2. Referring to fig. 9, the first projection device 110 may rotate the first marker graphic 142 in the first projection image 140 counterclockwise by (β - α)/2 and rotate the second marker graphic 152 in the second projection image 150 clockwise by (β - α)/2.

In the disclosed embodiment, referring to fig. 2, 3 and 10, the first edge overlap region 141 and the second edge overlap region 151 may both be rectangular regions. One first mark figure 142 is displayed at each top corner of the first edge overlap region 141 and one second mark figure 152 is displayed at each top corner of the second edge region 151.

Referring to fig. 2, 3 and 11, the first edge overlapping region 141 and the second edge overlapping region 151 may both be rectangular regions. The first edge overlap region 141 may display m rows and n columns of the first mark patterns 142, and the second edge region 151 may display m rows and n columns of the second mark patterns 152. Wherein M is a positive integer greater than 1 and less than M, and N is a positive integer greater than 1 and less than N.

In the embodiment of the present disclosure, if a plurality of first marker patterns are displayed in the first edge overlapping region and a plurality of second marker patterns are displayed in the second edge overlapping region, the first projection device may simultaneously adjust the projection position of the target projection image based on the marker patterns at the same position in the first edge overlapping region and the second edge overlapping region, thereby improving the efficiency of the adjustment of the projection position of the target projection image.

In the embodiment of the disclosure, taking the target projection image as the first projection image as an example, the first projection device may further include a light valve, where the light valve may be a Digital micro-mirror device (DMD), where a plurality of mirrors are integrated in the DMD, and each mirror corresponds to one pixel in the image to be projected.

For example, if the first projection image needs to be translated by k rows of pixels along the pixel column direction, the corresponding mirror for the first row of pixels may be adjusted to the mirror for the (k + 1) th row of pixels; for the second row of pixels, the corresponding mirror plate can be adjusted to the mirror plate corresponding to the k +2 th row of pixels. By analogy, for the nth row of pixels, the corresponding mirror plate can be adjusted to the mirror plate corresponding to the k + N th row of pixels. Wherein k is a positive integer less than N.

Alternatively, the first projection device may also adjust the projection position of the first projection image by adjusting its effective projection area based on the mark patterns on the corners at the same positions of the first edge overlapping area and the second edge area at the same time, so that the pixels in each corner of the first edge overlapping area and the second edge overlapping area completely coincide. After that, the first projection device may project and display the first projection image again after adjusting the effective projection area thereof, and instruct the second projection device to project and display a second projection image, where the first edge overlap area of the first projection image may display m rows and n columns of the first mark graphics, and the second edge area of the second projection image may display m rows and n columns of the second mark graphics. And performing the above steps 303 to 307 again to adjust the position of the effective projection area again, and further adjust the projection position of the first projection image to ensure that the pixels in the first edge overlapping area and the pixels in the second edge overlapping area are completely overlapped. Due to the fact that the positions of the projected images are adjusted for multiple times, accuracy of projected image correction is improved, and therefore seamless splicing of the first projected image and the second projected image is guaranteed.

In the embodiment of the present disclosure, the background color of the first projection image may be a first color, the color of the first marker graphic may be a second color, the background color of the second projection image may be a third color, and the color of the second marker graphic may be a fourth color. The first color is different from the second color, the first color is different from the fourth color, the third color is different from the second color, and the third color is different from the fourth color, so that the first projection device can recognize the first mark pattern and the second mark pattern in the shot image.

Optionally, the first color and the third color may be the same or different, and this is not limited in this disclosure. For example, the first color and the third color may both be white, the second color may be yellow, and the fourth color may be green.

It should be noted that if the sizes of the different projection images are the same and the area of the non-overlapping area of the first edge overlapping area and the second edge overlapping area exceeds 10% of the area of the projection image, the placement position of the projection device needs to be readjusted.

In the embodiment of the disclosure, by using the method for correcting the projection image provided by the application, even if the hanger of the projection device is slightly deformed by gravity or the position of the projection device is changed under the action of external force to cause the projection image to be blurred in the process of projecting the image through the projection device, the projection position of the projection image can be adjusted by using the steps 301 to 307, and a worker does not need to manually adjust the display position of the projection image projected and displayed by the projection device, so that the efficiency of correcting the projection image is improved.

It should be noted that the order of the steps of the correction method for the projected image provided by the embodiment of the present disclosure may be appropriately adjusted, and the steps may also be deleted according to the situation. For example, steps 304 to 307 may be deleted as appropriate, or step 305 may be deleted as appropriate, or step 307 may be performed before step 304. Any method that can be easily conceived by one skilled in the art within the technical scope of the present disclosure shall be covered within the protection scope of the present disclosure, and thus, the detailed description thereof shall not be repeated.

In summary, the present disclosure provides a method for correcting a projection image, where the method for correcting a projection image may capture a first projection image projected and displayed by a first projection device and a second projection image projected and displayed by a second projection device, so as to obtain a captured image. And when the area of the overlapping area of the first mark figure and the second mark figure in the shot image is determined to be smaller than the area threshold, adjusting the projection position of the target projection image until the area of the overlapping area of the first mark figure and the second mark figure is larger than or equal to the area threshold. The projection position of the target projection image can be adjusted based on the shot image shot by the camera, and the projection position of the projection image does not need to be manually adjusted by a worker, so that the efficiency and the reliability of projection image correction are improved, and meanwhile, the seamless splicing of two adjacent projection images is ensured.

In the embodiment of the present disclosure, referring to fig. 3, the first projection device 110 is configured to display a first projection image 140 in a projection manner in response to a correction instruction, and to send a projection instruction to the second projection device 120, wherein a first edge overlapping area 141 of the first projection image 140 is displayed with a first marker graphic 142.

In the embodiment of the present disclosure, the correction instruction may be triggered by a user through a remote controller, and the first projection device 110 is configured to, after receiving the correction instruction sent by the remote controller, project and display the first projection image 140 in response to the correction instruction, and send a projection instruction to the second projection device 120. Alternatively, the first projection device 110 may be provided with a correction button, and the first projection device 110 is configured to generate a correction instruction after detecting a click operation of a user on the correction button, and further, in response to the correction instruction, display the first projection image 140 in a projection manner, and send the projection instruction to the second projection device 120. Still alternatively, the first projection device 110 may periodically generate a correction instruction, and may project and display the first projection image 140 and send a projection instruction to the second projection device 120 in response to the correction instruction.

Referring to fig. 4, the second projection device 120 is configured to, after receiving the projection instruction sent by the first projection device 110, project and display a second projection image 150 in response to the projection instruction, where a second edge overlap area 151 of the second projection image 150 displays a second marker pattern 152.

The first edge overlapping area 141 and the second edge overlapping area 151 have the same size, and the display position of the first mark graphic 142 in the first edge overlapping area 141 is the same as the display position of the second mark graphic 152 in the second edge overlapping area 151.

The first edge overlap region 141 is a region of the first projection image that needs to overlap the second projection image 150, and the second edge overlap region 151 is a region of the second projection image that needs to overlap the first projection image 140. The first edge overlapping area 141 and the second edge overlapping area 151 have the same size, and the display position of the first mark figure 142 in the first edge overlapping area 141 is the same as the display position of the second mark figure 152 in the second edge overlapping area 151. Illustratively, the first mark pattern 142 is positioned at the left top corner of the first edge overlap region 141, and the second mark pattern 152 is positioned at the left top corner of the second edge overlap region 151.

Referring to fig. 5, the camera 130 is configured to capture the first projection image 140 and the second projection image 150 to obtain a captured image 160, and transmit the captured image 160 to the first projection device 110.

In the embodiment of the present disclosure, the photographing range of the camera 130 is greater than the projection range of the first projection device 110, so that the camera 130 can be ensured to photograph the first edge overlapping area 141 of the first projection image 140 and the second edge overlapping area 151 of the second projection image 150.

Optionally, a processor may be disposed in the first projection device 110, and the camera 130 may convert the captured image 160 into a digital signal after obtaining the captured image 160, and send the digital signal to the processor in the first projection device 110.

It should be noted that the camera 130 may also be disposed on the light exit side of the second projection device 120, or both the light exit side of the first projection device 110 and the light exit side of the second projection device 120 may be disposed with the camera 130, that is, the first projection device 110 and the second projection device 120 may respectively perform the steps 602 to 607, so as to further implement the correction of the projected image. Still alternatively, the video camera 130 may be provided separately from the projection device, for example, the video camera 130 may be a digital camera separate from the projection device. That is, in the embodiment of the present application, it is sufficient to ensure that the camera 130 can capture the first edge overlapping region 141 and the second edge overlapping region 151 and can transmit the captured images to the first projection device 110. The embodiment of the present disclosure does not limit the setting position of the camera 130.

The first projection device 110 is further configured to, when it is determined that the area of the overlapping region of the first mark figure 142 and the second mark figure 152 in the captured image 160 is smaller than the area threshold, adjust the projection position of the target projection image until the area of the overlapping region of the first mark figure 142 and the second mark figure 152 is greater than or equal to the area threshold. Wherein the target projection image may include at least one of the first projection image 140 and the second projection image 150.

In the embodiment of the present disclosure, the first projection device 110 is further configured to calculate the area of the overlapping region of the first mark pattern 142 and the second mark pattern 152 in the captured image 160 after receiving the captured image 160, and detect whether the area of the overlapping region of the first mark pattern 142 and the second mark pattern 152 is smaller than the area threshold. If the area of the overlapped area is smaller than the area threshold, it indicates that the overlapped area of the first edge overlapped area 141 of the first projection image 140 and the second edge overlapped area 151 of the second projection image 150 is small, and the overlapping degree of the two does not meet the requirement of the tiled display. The first projection device 110 may adjust the projection position of the target projection image until the area of the overlapping region of the first and second marker patterns 142 and 143 is greater than or equal to the area threshold.

If the area of the overlapped area is greater than or equal to the area threshold, which indicates that the overlapped area of the first edge overlapped area 141 of the first projection image 140 and the second edge overlapped area 151 of the second projection image 150 is large, and the overlapped degree of the two satisfies the requirement of the tiled display, the first projection device 110 does not need to adjust the projection position of the target projection image.

Wherein the area threshold may be a fixed value pre-stored in the first projection device. And may be determined based on the area of the smaller of the first and second marker patterns, for example, the area threshold may be 90%, 95%, or 100% of the area of the smaller of the first and second marker patterns.

In summary, the embodiments of the present disclosure provide a projection system, which may include a first projection device and a second projection device arranged adjacently, and a camera. The camera is used for shooting the first projection image projected and displayed by the first projection equipment and the second projection image projected and displayed by the second projection equipment to obtain shot images. The first projection device is used for adjusting the projection position of the target projection image when the area of the overlapped area of the first mark graph and the second mark graph in the shot image is determined to be smaller than the area threshold value until the area of the overlapped area of the first mark graph and the second mark graph is larger than or equal to the area threshold value. Because the first projection equipment can adjust the projection position of the target projection image based on the shot image shot by the camera, the projection position of the projection image does not need to be manually adjusted by a worker, the efficiency and the reliability of projection image correction are improved, and meanwhile, seamless splicing of two adjacent projection images is ensured.

In the embodiment of the present disclosure, if the target projection image is the first projection image 140 or the second projection image 150. Referring to fig. 7, the first projection device 110 is further configured to, when it is determined that the number of pixels between the center point O1 of the first marker pattern 142 and the center point O2 of the second marker pattern 152 in the captured image 160 is greater than the number threshold, translate the projection position of the target projection image until the number of pixels between the center point O1 of the first marker pattern 142 and the center point O2 of the second marker pattern 152 is less than or equal to the number threshold. The first projection device 110 may not need to translate the projection location of the first projected image 140 when it is determined that the number of pixels d is less than or equal to the number threshold.

Alternatively, the step 604 may be referred to in the process of determining the number d of pixels by the first projection device 110, and the step 605 may be referred to in the process of translating the projection position of the target projection image by the first projection device 110. The embodiments of the present disclosure are not described herein in detail.

In the embodiment of the present disclosure, the first projection device 110 is further configured to determine an included angle between the first axis of the first mark pattern 142 and the second axis of the second mark pattern 152 in the captured image 160 after determining that the number d of pixels between the center point O1 of the first mark pattern 142 and the center point O2 of the second mark pattern 152 is less than or equal to the number threshold, and detect whether the included angle between the first axis and the second axis is greater than the angle threshold. When the first projection device 110 determines that the included angle between the first axis and the second axis is greater than the angle threshold, which indicates that the degree of coincidence between the first marker pattern 142 in the first projection image 140 and the second marker pattern 152 in the second projection image 150 does not satisfy the requirement of the mosaic display, the projection position of the target projection image may be rotated until the included angle between the first axis and the second axis is less than or equal to the angle threshold, that is, until the degree of coincidence between the first marker pattern 142 in the first projection image 140 and the second marker pattern 152 in the second projection image 150 satisfies the requirement of the mosaic display. When the first projection device 110 determines that the included angle between the first axis and the second axis is smaller than or equal to the angle threshold, indicating that the coincidence degree between the first mark pattern 142 and the second mark pattern 152 in the captured image 160 satisfies the stitching requirement, the projection position of the first projection image 140 is not rotated.

Alternatively, the first marker graphic 142 and the second marker graphic 152 may be both cross-shaped, the first axis may be a horizontal line of the first marker graphic 142, and the second axis may be a horizontal line of the second marker graphic 152.

Referring to fig. 5 and 7, the first axis is parallel to the first side of the first edge overlapping region 141, the second axis is parallel to the first side of the second edge overlapping region 151, each of the edge overlapping regions may be rectangular, and the first side of each of the edge overlapping regions may be parallel to the pixel row direction or the pixel column direction of the edge overlapping region. I.e. the first axis is parallel to the second axis. Referring to fig. 8 and 9, the first axis is non-parallel to the second axis.

In the disclosed embodiment, the process of the first projection device 110 determining the included angle between the first axis and the second axis may refer to step 606 described above. The process of rotating the projection position of the target projection image by the first projection device 110 may refer to step 607 described above. The embodiments of the present disclosure are not described herein in detail.

In the disclosed embodiment, the target projection image may include a first projection image and a second projection image. Referring to fig. 7, 8 and 9, when the first projection device 110 determines that the number of pixels between the center point O1 of the first marker pattern 142 and the center point O2 of the second marker pattern 152 is greater than the number threshold, indicating that the degree of coincidence between the center point O1 of the first marker pattern 142 of the first projection image 140 and the center point O2 of the second marker pattern 152 of the second projection image 150 does not satisfy the requirement of the mosaic display, the first projection device 110 is configured to respectively shift the projection position of each pixel of the first projection image 140 and the projection position of each pixel of the second projection image 150 until the number of pixels between the center point O1 of the first marker pattern 142 and the center point O2 of the second marker pattern 152 is less than or equal to the number threshold. When it is determined that the first projection device 110 determines that the number d of pixels is less than or equal to the number threshold, it indicates that the center point O1 of the first marker pattern 142 in the first projection image 140 and the center point O2 of the second marker pattern 152 in the second projection image 150 overlap to a degree that meets the requirements of the tiled display. The first projection device 110 need not separately translate the projection position of the first projection image 140 and the projection position of the second projection image 150.

Alternatively, the process of the first projection device 110 respectively translating the projection position of the first projection image and the projection position of the second projection image may refer to step 605. The embodiments of the present disclosure are not described herein in detail.

In the embodiment of the present disclosure, after determining that the number d of pixels between the center point O1 of the first mark pattern 142 and the center point O2 of the second mark pattern 152 is less than or equal to the number threshold, the first projection device 110 is further configured to determine an included angle between the first axis of the first mark pattern 142 and the second axis of the second mark pattern 152 in the captured image 160, and detect whether the included angle between the first axis and the second axis is greater than the angle threshold. When it is determined that the included angle between the first axis and the second axis is greater than the angle threshold, the first projection device 110 respectively rotates the projection position of the first projection image 140 and the projection position of the second projection image 150 until the included angle between the first axis and the second axis is less than or equal to the angle threshold. The first projection device 110 does not need to rotate the projection position of the first projection image 140 and the projection position of the second projection image 150, respectively, when it is determined that the included angle between the first axis and the second axis is less than or equal to the angle threshold.

In the embodiment of the present disclosure, the process of rotating the projection position of the first projection image and the projection position of the second projection image by the first projection device 110 may refer to step 607 described above. The embodiments of the present disclosure are not described herein in detail.

Referring to fig. 2, 3 and 10, the first edge overlap region 141 and the second edge overlap region 151 may each be a rectangular region. A first marking pattern 142 is displayed at each top corner of the first edge overlapping region 141 and a second marking pattern 152 is displayed at each top corner of the second edge region 151.

Referring to fig. 2, 3 and 11, the first edge overlapping region 141 and the second edge overlapping region 151 may both be rectangular regions. The first edge overlapping area 141 may display m rows and n columns of the first mark patterns 142, and the second edge area 151 may display m rows and n columns of the second mark patterns 152.

In the embodiment of the present disclosure, if a plurality of first marker patterns 141 are displayed in the first edge overlapping region 141 and a plurality of second marker patterns 152 are displayed in the second edge overlapping region 151, the first projection device 110 may simultaneously adjust the projection position of the target projection image based on the marker patterns at the same position in the first edge overlapping region 141 and the second edge overlapping region 151, thereby improving the efficiency of the adjustment of the projection position of the target projection image.

In this disclosure, taking the target projection image as the first projection image as an example, the first projection device may further include a light valve, where the light valve may be a DMD, and a plurality of mirrors are integrated in the DMD, and each mirror corresponds to one pixel in the image to be projected. The deflection angle of each mirror in the DMD is different, so that different pixels can be projected to different positions. When adjusting the position of the first projection image, the first projection device may adjust its effective projection area by adjusting the correspondence between the pixels and the mirror (i.e., adjusting the mirror for reflecting the light of each pixel), thereby adjusting the projection position of the first projection image. The effective projection area of the first projection device is a display area of an image projected and displayed by the first projection device.

Alternatively, the first projection device 110 may also adjust the projection position of the first projection image by adjusting its effective projection area based on the mark patterns on the corners at the same positions of the first edge overlapping area 141 and the second edge area 151 at the same time, so that the pixels in each corner of the first edge overlapping area 141 and the second edge overlapping area 151 completely coincide. Thereafter, the first projection device 110 may project and display the first projection image 140 again after adjusting the effective projection area thereof, and instruct the second projection device 120 to project and display the second projection image 150, where the first edge overlap area 141 of the first projection image 140 may display m rows and n columns of the first marker patterns 142, and the second edge area 151 of the second projection image 150 may display m rows and n columns of the second marker patterns 152. The camera 130 may capture the first and second projected

images

140 and 150 again to obtain a captured image 160, and send the captured image 160 to the first projection device 110. The first projection device 110 may simultaneously adjust the position of its effective projection area, and thus the projection position of the first projection image, based on the marker patterns at the same positions in the first edge overlap area 141 and the second edge overlap area 151 to ensure that the pixels in the first edge overlap area 141 and the pixels in the second edge overlap area 151 completely coincide. Due to the fact that the positions of the projected images are adjusted for multiple times, accuracy of projected image correction is improved, and therefore seamless splicing of the first projected image and the second projected image is guaranteed.

In the embodiment of the present disclosure, the background color of the first projection image 140 may be a first color, the color of the first marker graphic 142 may be a second color, the background color of the second projection image 150 may be a third color, and the color of the second marker graphic 152 may be a fourth color. Wherein the first color is different from the second color, the first color is different from the fourth color, the third color is different from the second color, and the third color is different from the fourth color, thereby ensuring that the first projection device 110 can recognize the first mark pattern 142 and the second mark pattern 152 in the photographed image 160.

Referring to fig. 1, each projection apparatus may further include a projection lens 00, where the projection lens 00 is configured to project an image beam onto a projection screen.

In the embodiment of the disclosure, by using the projection system provided by the application, in the process of projecting an image through the projection device, even if the hanger of the projection device is slightly deformed by gravity or the position of the projection device is changed under the action of external force, so that the projection position of the projected image is changed, the display position of the projected image projected and displayed by the projection device can be adjusted without a worker, and the efficiency of correcting the projected image is improved.

In summary, the embodiments of the present disclosure provide a projection system, which may include a first projection device and a second projection device arranged adjacently, and a camera. The camera is used for shooting the first projection image projected and displayed by the first projection equipment and the second projection image projected and displayed by the second projection equipment to obtain shot images. The first projection device is used for adjusting the projection position of the target projection image when the area of the overlapped area of the first mark figure and the second mark figure in the shot image is determined to be smaller than the area threshold value until the area of the overlapped area of the first mark figure and the second mark figure is larger than or equal to the area threshold value. Because the first projection equipment can adjust the projection position of the target projection image based on the shot image shot by the camera, the projection position of the projection image does not need to be manually adjusted by a worker, the efficiency and the reliability of projection image correction are improved, and meanwhile, seamless splicing of two adjacent projection images is ensured.

Fig. 12 is a schematic structural diagram of a projection apparatus provided in an embodiment of the present disclosure. The projection device may be the first projection device in the projection system shown in fig. 1, and the projection device includes a light source 111, a light valve 112, a projection lens 00, and a processor 113.

The light source 111 is configured to emit light of a plurality of different colors, for example, the light source 111 may be a laser light source configured to emit red laser light, blue laser light, and green laser light. The light valve 112 is used for modulating each color light into an image beam and transmitting the image beam to the projection lens. The light valve may be a DMD. The projection lens 00 is used for projecting an image beam onto a projection screen. The processor 113 is used to implement the correction method of the projected image shown in fig. 2 or fig. 6.

The embodiment of the present disclosure provides a computer-readable storage medium having instructions stored therein, which when run on a computer, cause the computer to execute a method of correcting a projected image as shown in fig. 2 or fig. 6.

The above description is intended to be exemplary only and not to limit the present disclosure, and any modification, equivalent replacement, or improvement made without departing from the spirit and scope of the present disclosure is to be considered as the same as the present disclosure.

Claims

1. A method for correcting a projected image, the method being applied to a first projection device in a projection system, the projection system further comprising: a second projection device arranged adjacent to the first projection device, and a camera; the method comprises the following steps:

in response to a correction instruction, a first projection image is displayed in a projection mode, and the second projection device is instructed to display a second projection image in a projection mode, wherein a first edge overlapping area of the first projection image is displayed with a first mark graph, a second edge overlapping area of the second projection image is displayed with a second mark graph, the first edge overlapping area and the second edge overlapping area are the same in size, and the display position of the first mark graph in the first edge overlapping area is the same as the display position of the second mark graph in the second edge overlapping area;

acquiring a shot image obtained by shooting the first projection image and the second projection image by the camera, wherein the shot image at least comprises a first edge overlapping area of the first projection image and a second edge overlapping area of the second projection image, and the camera can identify a first mark graph and a second mark graph in the shot image;

if the area of the overlapping region of the first mark graph and the second mark graph in the shot image is smaller than an area threshold value, adjusting the projection position of a target projection image until the area of the overlapping region of the first mark graph and the second mark graph is larger than or equal to the area threshold value;

2. The method of claim 1, wherein the target projection image is the first projection image or the second projection image, and wherein the adjusting the projection position of the target projection image comprises:

if the number of pixels between the center point of the first marking graph and the center point of the second marking graph is larger than a number threshold, translating the projection position of the target projection image until the number of pixels between the center point of the first marking graph and the center point of the second marking graph is smaller than or equal to the number threshold;

if the included angle between the first axis of the first mark graph and the second axis of the second mark graph is larger than an angle threshold value, rotating the projection position of the target projection image until the included angle between the first axis and the second axis is smaller than or equal to the angle threshold value;

the first axis is parallel to a first side of the first edge overlapping region, the second axis is parallel to a first side of the second edge overlapping region, each edge overlapping region is rectangular, and the first side of each edge overlapping region is parallel to a pixel row direction or a pixel column direction of the edge overlapping region.

3. The method of claim 1, wherein the target projection image comprises the first projection image and the second projection image; the adjusting of the projection position of the target projection image comprises:

if the number of pixels between the center point of the first marker graphic and the center point of the second marker graphic is larger than a number threshold, respectively translating the projection position of the first projection image and the projection position of the second projection image until the number of pixels between the center point of the first marker graphic and the center point of the second marker graphic is smaller than or equal to the number threshold;

if the included angle between the first axis of the first marking graph and the second axis of the second marking graph is larger than an angle threshold, respectively rotating the projection position of the first projection image and the projection position of the second projection image until the included angle between the first axis and the second axis is smaller than or equal to the angle threshold;

wherein the first axis is parallel to a first side of the first edge overlapping region, the second axis is parallel to a first side of the second edge overlapping region, each of the edge overlapping regions is rectangular, and the first side of each of the edge overlapping regions is parallel to a pixel row direction or a pixel column direction of the edge overlapping region.

4. The method of any one of claims 1 to 3, wherein the first edge overlap region and the second edge overlap region are both rectangular regions;

one first marking pattern is displayed at each top corner of the first edge overlapping region, and one second marking pattern is displayed at each top corner of the second edge region.

5. A method according to any one of claims 1 to 3, wherein the first and second patterns of indicia are both cross patterns.

6. The method according to any one of claims 1 to 3, wherein the background color of the first projected image is a first color, the color of the first marker graphic is a second color, the background color of the second projected image is a third color, and the color of the second marker graphic is a fourth color;

wherein the first color is different from the second color, the first color is different from the fourth color, the third color is different from the second color, and the third color is different from the fourth color.

7. A projection system, comprising a first projection device and a second projection device arranged adjacently, and a camera;

the second projection device is used for responding to the projection instruction and displaying a second projection image in a projection mode, and a second edge overlapping area of the second projection image displays a second mark graph, wherein the size of the first edge overlapping area is the same as that of the second edge overlapping area, and the display position of the first mark graph in the first edge overlapping area is the same as that of the second mark graph in the second edge overlapping area;

the camera is used for shooting the first projection image and the second projection image to obtain a shot image, and sending the shot image to the first projection device, wherein the shot image at least comprises a first edge overlapping area of the first projection image and a second edge overlapping area of the second projection image, and the camera can identify a first mark graph and a second mark graph in the shot image;

the first projection device is further used for adjusting the projection position of the target projection image when the area of the overlapping region of the first marker pattern and the second marker pattern in the shot image is determined to be smaller than an area threshold value until the area of the overlapping region of the first marker pattern and the second marker pattern is larger than or equal to the area threshold value; wherein the target projection image includes at least one of the first projection image and the second projection image.

8. The projection system of claim 7, wherein the target projection image is the first projection image or the second projection image; the first projection device is configured to:

when the number of pixels between the central point of the first marking graph and the central point of the second marking graph is determined to be larger than a number threshold, translating the projection position of the target projection image until the number of pixels between the central point of the first marking graph and the central point of the second marking graph is smaller than or equal to the number threshold;

when the included angle between the first axis of the first marking graph and the second axis of the second marking graph is determined to be larger than an angle threshold, rotating the projection position of the target projection image until the included angle between the first axis and the second axis is smaller than or equal to the angle threshold;

9. The projection system of claim 7, wherein the target projection image comprises the first projection image and the second projection image; the first projection device is configured to:

when the number of pixels between the central point of the first marker graph and the central point of the second marker graph is determined to be larger than a number threshold, respectively translating the projection position of the first projection image and the projection position of the second projection image until the number of pixels between the central point of the first marker graph and the central point of the second marker graph is smaller than or equal to the number threshold;

when the included angle between the first axis of the first marking graph and the second axis of the second marking graph is determined to be larger than an angle threshold, respectively rotating the projection position of the first projection image and the projection position of the second projection image until the included angle between the first axis and the second axis is smaller than or equal to the angle threshold;

10. A projection device, characterized in that the projection device comprises: the system comprises a light source, a light valve, a projection lens and a processor;

the light source is used for emitting light of a plurality of different colors;

the projection lens is used for projecting the image light beam onto a projection screen;

the processor is used to implement the method of correction of a projected image as claimed in any one of claims 1 to 6.