CN115278184B

CN115278184B - Projection picture correction method and device

Info

Publication number: CN115278184B
Application number: CN202210840690.6A
Authority: CN
Inventors: 王豪庆; 曹嘉航; 梁翔宇
Original assignee: Formovie Chongqing Innovative Technology Co Ltd
Current assignee: Formovie Chongqing Innovative Technology Co Ltd
Priority date: 2022-07-18
Filing date: 2022-07-18
Publication date: 2024-03-15
Anticipated expiration: 2042-07-18
Also published as: CN115278184A

Abstract

The application relates to a projection picture correction method, a projection picture correction device, a computer device and a storage medium. The method comprises the following steps: acquiring an initial image shot by the mobile device for a projection curtain; a first projection picture projected by a projector is displayed in a projection curtain in the initial image; a plurality of characteristic patterns are displayed in the first projection picture; the positions of the plurality of feature patterns in the initial image correspond to the shooting pose of the mobile device; determining position information of a plurality of characteristic patterns in an initial image, and determining an actual shooting gesture of the mobile device when shooting the initial image based on the position information; if the actual shooting gesture does not accord with the preset shooting gesture, controlling the rotation of the initial image to obtain a target image; the correction instruction information is acquired based on the target image, and the correction instruction information is transmitted to the projector, so that the projector corrects the projected second projection picture and the projection curtain based on the correction instruction information. The method can improve the use flexibility.

Description

Projection picture correction method and device

Technical Field

The present disclosure relates to the field of projection technologies, and in particular, to a method and apparatus for correcting a projection image.

Background

A projector is a device that projects images or video onto a projection screen and can be connected to a computer, a game machine, a memory, etc. through different interfaces to play a corresponding video signal. When the projector is used, the projection picture and the projection curtain are required to be aligned so as to achieve better watching effect.

With the continuous popularization of projectors, some projectors on the market at present need to correct images manually, and some projectors have an automatic image correction function, but the projectors themselves need to have hardware configuration capable of realizing automatic alignment, so that the projectors are not flexible to use.

Disclosure of Invention

In view of the above, it is desirable to provide a projection screen correction method and apparatus that can improve the flexibility of use.

In a first aspect, the present application provides a projection screen correction method. The method comprises the following steps:

acquiring an initial image shot by the mobile device for a projection curtain; a first projection picture projected by a projector is displayed in a projection curtain in the initial image; a plurality of characteristic patterns are displayed in the first projection picture; the positions of the plurality of feature patterns in the initial image correspond to shooting attitudes of the mobile device;

Determining position information of a plurality of characteristic patterns in the initial image, and determining an actual shooting gesture of the mobile device when shooting the initial image based on the position information;

if the actual shooting gesture does not accord with the preset shooting gesture, controlling the initial image to rotate so as to obtain a target image;

and acquiring correction instruction information based on the target image, and sending the correction instruction information to the projector, so that the projector corrects the projected second projection picture to align with the projection curtain based on the correction instruction information.

In one embodiment, the number of feature patterns is N; the determining the position information of the characteristic pattern in the initial image, and determining the actual shooting gesture of the mobile device when shooting the initial image based on the position information comprises:

identifying a target graph which is the same as the shape of the characteristic pattern in the initial image; the target graph at least comprises the characteristic pattern;

respectively calculating distances from the graphic center points of the plurality of target graphics to the center points of the initial images;

screening N graphic center points with distances meeting preset conditions from the graphic center points of a plurality of target graphics to obtain the graphic center points of each characteristic pattern in the first projection picture;

And determining the actual shooting gesture of the mobile equipment when shooting the initial image according to the position information of the graphic center point of the screened characteristic pattern.

In one embodiment, the correction instruction information is a target vertex coordinate of the projection curtain under a target coordinate system; the first projection picture is a projection picture which is subjected to scaling projection by the projector at a preset scaling rate; the acquiring correction instruction information based on the target image includes:

determining a first vertex coordinate of the first projection picture in the target image under an image coordinate system and a second vertex coordinate of a projection curtain under the image coordinate system;

and performing coordinate conversion calculation based on the first vertex coordinates, the second vertex coordinates and the preset scaling rate to obtain target vertex coordinates of the projection curtain under a target coordinate system.

In one embodiment, the determining the first vertex coordinates of the first projection screen in the target image in the image coordinate system and the second vertex coordinates of the projection screen in the image coordinate system includes:

clearing a plurality of the characteristic patterns displayed in the initial image or the target image so that a first projection picture of the initial image is solid;

Performing contour edge detection on the first projection picture of the solid color in the initial image or the target image and the projection curtain to obtain a contour image;

and determining a first vertex coordinate of the first projection picture in the target image under an image coordinate system and a second vertex coordinate of a projection curtain under the image coordinate system based on the contour image.

In one embodiment, the clearing the plurality of the feature patterns displayed in the initial image or the target image so that the first projection screen of the initial image is solid includes:

determining a geometric figure area which covers the characteristic pattern and is positioned in the first projection picture;

and modifying pixel values of pixel points in the geometric figure area to clear the displayed characteristic pattern in the initial image so that a projection picture of the initial image is solid.

In one embodiment, the feature pattern is circular; the geometric figure area is a rectangular area; the determining a geometric area that covers the feature pattern and is located within the projection screen includes:

determining the coordinates and the radius of the graphics center points of each of the circles;

Determining rectangular areas covering the circles according to the radius and the coordinates of the graphic center points; the side length of the rectangular region is greater than or equal to the diameter of the circle.

In one embodiment, the number of the feature patterns is three, and the central points of the three feature patterns form a right triangle; the modifying pixel values of pixel points within the geometric area includes:

determining first center point coordinates of the graphics center points of the three feature patterns respectively;

determining second center point coordinates of a fourth graphic center point based on the three first center point coordinates; the second center point coordinates and the three first center point coordinates form a rectangular quadrilateral;

carrying out average calculation on the second center point coordinates and the three first center point coordinates to obtain average center point coordinates;

and modifying the pixel values of the pixel points in the geometric figure region to the pixel values at the average center point coordinates.

In one embodiment, the projector and the projection screen are disposed on the same placement surface.

In a second aspect, the present application further provides a projection screen correction apparatus. The device comprises:

An image acquisition module for acquiring an initial image taken by the mobile device for the projection curtain; a first projection picture projected by a projector is displayed in a projection curtain in the initial image; a plurality of characteristic patterns are displayed in the first projection picture; the positions of the plurality of feature patterns in the initial image correspond to shooting attitudes of the mobile device;

an image rotation module, configured to determine position information of a plurality of feature patterns in the initial image, and determine an actual shooting pose when the mobile device shoots the initial image based on the position information; if the actual shooting gesture does not accord with the preset shooting gesture, controlling the initial image to rotate so as to obtain a target image;

and the correction module is used for acquiring correction instruction information based on the target image and sending the correction instruction information to the projector, so that the projector corrects the projected second projection picture and the projection curtain based on the correction instruction information.

According to the projection picture correction method and device, the initial image shot by the mobile equipment aiming at the projection curtain is acquired; and a first projection picture projected by the projector is displayed in the projection curtain in the initial image. The first projection picture is provided with a plurality of characteristic patterns. The positions of the plurality of feature patterns in the initial image correspond to a shooting pose of the mobile device. Position information of a plurality of the characteristic patterns in the initial image is determined, and an actual shooting gesture when the mobile device shoots the initial image is determined based on the position information. And if the actual shooting gesture does not accord with the preset shooting gesture, controlling the initial image to rotate so as to obtain a target image. Therefore, the shooting image shot in the preset shooting posture can be obtained without installing a camera on the projector, the hardware cost is reduced, shooting can be performed in any posture, and therefore complexity is reduced, and flexibility is improved. Correction instruction information is acquired based on the target image. Therefore, the target image accords with the preset shooting gesture, the processing process of acquiring the correction instruction information is consistent, the complexity of the correlation calculation of the correction instruction information is reduced, and the calculation efficiency is improved. And transmitting the correction instruction information to the projector, so that the projector corrects the projected second projection picture to align with the projection curtain based on the correction instruction information. Therefore, under the conditions that the projector has no hardware requirement and the actual shooting posture of the initial image has no requirement, the automatic identification of the actual shooting posture is realized, the target image which accords with the preset shooting posture is obtained, and the correction is completed based on the target image, so that the flexibility is improved.

In a third aspect, the present application provides a projection screen correction method. The method comprises the following steps:

shooting a projection curtain to obtain an initial image; a first projection picture projected by a projector is displayed in a projection curtain in the initial image; a plurality of characteristic patterns are displayed in the first projection picture; the positions of the plurality of feature patterns in the initial image correspond to shooting attitudes of the mobile device;

the initial image is sent to a server, the server is triggered to determine the position information of a plurality of characteristic patterns in the initial image, and the actual shooting gesture when the initial image is shot is determined based on the position information; if the actual shooting gesture does not accord with the preset shooting gesture, controlling the initial image to rotate so as to obtain a target image; acquiring correction instruction information based on the target image; and transmitting the correction instruction information;

and receiving the correction instruction information and sending the correction instruction information to the projector, so that the projector corrects the projected second projection picture to align with the projection curtain based on the correction instruction information.

In a fourth aspect, the present application further provides a projection screen correction apparatus. The device comprises:

The shooting module is used for shooting the projection curtain to obtain an initial image; a first projection picture projected by a projector is displayed in a projection curtain in the initial image; a plurality of characteristic patterns are displayed in the first projection picture; the positions of the plurality of feature patterns in the initial image correspond to shooting attitudes of the mobile device;

the sending module is used for sending the initial image to a correction cloud, triggering the correction cloud to determine the position information of a plurality of characteristic patterns in the initial image, and determining the actual shooting gesture when the initial image is shot based on the position information; if the actual shooting gesture does not accord with the preset shooting gesture, controlling the initial image to rotate so as to obtain a target image; acquiring correction instruction information based on the target image; and transmitting the correction instruction information;

and the receiving module is used for receiving the correction instruction information and sending the correction instruction information to the projector, so that the projector corrects the projected second projection picture and the projection curtain based on the correction instruction information.

According to the projection picture correction method and device, the initial image is obtained by shooting the projection curtain; a first projection picture projected by a projector is displayed in a projection curtain in the initial image; a plurality of characteristic patterns are displayed in the first projection picture; the positions of the plurality of feature patterns in the initial image correspond to a shooting pose of the mobile device. The initial image is sent to a server, the server is triggered to determine the position information of a plurality of characteristic patterns in the initial image, and the actual shooting gesture when the initial image is shot is determined based on the position information; if the actual shooting gesture does not accord with the preset shooting gesture, controlling the initial image to rotate so as to obtain a target image; acquiring correction instruction information based on the target image; and transmitting the correction instruction information. And receiving the correction instruction information and sending the correction instruction information to the projector, so that the projector corrects the projected second projection picture to align with the projection curtain based on the correction instruction information. Therefore, under the conditions that the projector has no hardware requirement and the actual shooting posture of the initial image has no requirement, the automatic identification of the actual shooting posture is realized, the target image which accords with the preset shooting posture is obtained, and the correction is completed based on the target image, so that the flexibility is improved.

In a fifth aspect, the present application provides a projection screen correction method. The method comprises the following steps:

projecting a first projection picture in a projection curtain; a plurality of characteristic patterns are displayed in the first projection picture; the positions of the plurality of feature patterns in the initial image correspond to shooting attitudes of the mobile device;

acquiring correction indication information; the correction instruction information is obtained based on the target image; the target image is obtained by controlling an initial image obtained by shooting the projection curtain to rotate under the condition that the actual shooting gesture is not consistent with the preset shooting gesture; the actual shooting gesture is obtained according to the position information of a plurality of characteristic patterns in the initial image;

and correcting based on the correction indication information to align the projected second projection picture with the projection curtain.

In a sixth aspect, the present application further provides a projection screen correction apparatus. The device comprises:

the projection module is used for projecting the first projection picture in the projection curtain; a plurality of characteristic patterns are displayed in the first projection picture; the positions of the plurality of feature patterns in the initial image correspond to shooting attitudes of the mobile device;

The acquisition module is used for acquiring correction instruction information; the correction instruction information is obtained based on the target image; the target image is obtained by controlling an initial image obtained by shooting the projection curtain to rotate under the condition that the actual shooting gesture is not consistent with the preset shooting gesture; the actual shooting gesture is obtained according to the position information of a plurality of characteristic patterns in the initial image;

and the correction module is used for correcting the projected second projection picture and the projection curtain based on the correction indication information.

The projection picture correction method and the projection picture correction device are used for projecting a first projection picture into a projection curtain. Wherein, a plurality of characteristic patterns are displayed in the first projection picture; the positions of the plurality of feature patterns in the initial image correspond to a shooting pose of the mobile device. Acquiring correction indication information; the correction instruction information is obtained based on the target image; the target image is obtained by controlling an initial image obtained by shooting the projection curtain to rotate under the condition that the actual shooting gesture is not consistent with the preset shooting gesture; the actual shooting attitude is obtained according to position information of a plurality of the feature patterns in the initial image. And correcting based on the correction indication information to align the projected second projection picture with the projection curtain. Therefore, under the conditions that the projector has no hardware requirement and the actual shooting posture of the initial image has no requirement, the automatic identification of the actual shooting posture is realized, the target image which accords with the preset shooting posture is obtained, and the correction is completed based on the target image, so that the flexibility is improved.

Drawings

FIG. 1 is a diagram of an application environment of a projection screen correction method according to an embodiment;

FIG. 2 is a flow chart of a method for correcting a projection screen according to an embodiment;

FIG. 3 is a schematic diagram of a projection screen calibration method according to an embodiment;

FIG. 4 is a schematic diagram of a projection screen calibration method according to an embodiment;

FIG. 5 is a flowchart of a method for correcting a projection screen according to an embodiment;

FIG. 6 is a flowchart of a method for correcting a projection screen according to an embodiment;

FIG. 7 is a block diagram showing a configuration of a projection screen correcting apparatus according to an embodiment;

FIG. 8 is a block diagram showing a configuration of a projection screen correcting apparatus according to an embodiment;

FIG. 9 is a block diagram showing a configuration of a projection screen correcting apparatus according to an embodiment;

FIG. 10 is an internal block diagram of a computer device in one embodiment;

FIG. 11 is an internal block diagram of a computer device in one embodiment.

Detailed Description

In order to make the objects, technical solutions and advantages of the present application more apparent, the present application will be further described in detail with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the present application.

The projection picture correction method provided by the embodiment of the application can be applied to an application environment shown in fig. 1. Wherein mobile device 110 communicates with server 120 and projector 130 over a network. The data storage system may store data that the server 120 needs to process. The data storage system may be integrated on the server 120 or may be located on a cloud or other network server. The mobile device 110 is a photographable device, and may be, but not limited to, various personal computers, notebook computers, smartphones, tablet computers, and portable wearable devices, and the server 120 may be implemented by a stand-alone server or a server cluster formed by a plurality of servers.

In one embodiment, server 120 may also be replaced by a terminal, which is not limited in this regard.

The mobile device 110 captures an initial image for the projection curtain. The mobile device 110 sends the initial image to the server 120. The server 120 obtains an initial image taken by the mobile device for the projection curtain. A first projection screen projected by the projector 130 is displayed in a projection curtain in the initial image; a plurality of characteristic patterns are displayed in the first projection picture; the positions of the plurality of feature patterns in the initial image correspond to a shooting pose of the mobile device. The server 120 determines position information of a plurality of feature patterns in the initial image, and determines an actual photographing pose when the mobile device photographs the initial image based on the position information. If the actual photographing posture does not match the preset photographing posture, the server 120 controls the initial image to rotate to obtain the target image. The server 120 acquires correction instruction information based on the target image and transmits the correction instruction information to the projector 130, so that the projector 130 corrects to align the projected second projection screen and the projection curtain based on the correction instruction information.

In one embodiment, as shown in fig. 2, a projection screen correction method is provided, where the method is applied to a server for illustration, it is understood that the method may also be applied to a terminal, and may also be applied to a system including the terminal and the server, and implemented through interaction between the terminal and the server. In this embodiment, the method includes the steps of:

s202, acquiring an initial image shot by a mobile device for a projection curtain; a first projection picture projected by a projector is displayed in a projection curtain in the initial image; a plurality of characteristic patterns are displayed in the first projection picture; the positions of the plurality of feature patterns in the initial image correspond to a shooting pose of the mobile device.

The mobile device is a mobile computer device with shooting function such as a mobile phone terminal and a notebook computer. The feature pattern is a pattern recognizable by the computer device, for example, it may be a geometric figure of a circle, a rectangle, a triangle, etc., preferably, the feature pattern is a geometric figure of a regular shape.

Specifically, the projector projects a first projection screen into the projection curtain. After shooting the projection curtain, the mobile device transmits the initial image obtained through shooting to a server. The server acquires an initial image. The first projection picture projected by the projector is displayed in the projection curtain in the initial image. The first projection picture is displayed with a plurality of characteristic patterns, and the positions of the characteristic patterns in the initial image correspond to the shooting gesture of the mobile device. It can be appreciated that the plurality of feature patterns are positioned differently in the initial image at different shooting attitudes.

S204, determining position information of a plurality of characteristic patterns in an initial image, and determining an actual shooting gesture of the mobile device when shooting the initial image based on the position information; and if the actual shooting gesture does not accord with the preset shooting gesture, controlling the rotation of the initial image to obtain a target image.

Specifically, the server identifies a plurality of feature patterns in the initial image, establishes an image coordinate system, determines position information of the plurality of feature patterns in the initial image under the image coordinate system, and determines an actual shooting pose when the mobile device shoots the initial image based on the position information. If the actual shooting gesture does not accord with the preset shooting gesture, the server controls the initial image to rotate so as to obtain a target image.

As shown in fig. 3, when the projection screen is photographed using the mobile device, a photographing posture of a horizontal screen with a camera to the right, a photographing posture of a horizontal screen with a camera to the left, or a vertical screen posture may be adopted, and initial images obtained by photographing are shown in fig. 3 (a), 3 (b), and 3 (c), respectively. Assuming that the preset photographing posture is the portrait posture, the initial images in fig. 3 (a) and 3 (b) are not photographed in conformity with the preset photographing posture. Therefore, it is necessary to rotate the initial image so as to obtain a target image conforming to a preset shooting attitude, i.e., an image shot in a vertical screen attitude as shown in fig. 3 (c). Therefore, the shooting gesture is not required to be limited when the initial image is shot, shooting can be carried out in any gesture, and the server can automatically adjust and rotate the initial image so as to obtain the target image which accords with the preset shooting gesture, so that the complexity is reduced, the flexibility is improved, the operation requirement on a user is reduced, and errors are avoided.

In one embodiment, the server may identify a target pattern in the initial image that is the same shape as the feature pattern, and screen out a target pattern closest to a center point of the initial image from among a plurality of target patterns as the feature pattern.

In one embodiment, the server invokes an Opencv (a cross-platform computer vision and machine learning software library based on BSD license (open source) release) computer vision software library for picture preprocessing. Firstly converting an initial image into a gray level image, then calling a Gaussian filter function in Opencv to reduce noise of the initial image, obtaining a preprocessed initial image, and rotating the preprocessed initial image to obtain a target image conforming to a preset shooting gesture.

S206, acquiring correction instruction information based on the target image, and sending the correction instruction information to the projector, so that the projector corrects the projected second projection picture and the projection curtain based on the correction instruction information.

Specifically, the server acquires correction instruction information based on the target image, and transmits the correction instruction information to the projector. After receiving the correction instruction information, the projector corrects the projected second projection picture to align with the projection curtain based on the correction instruction information.

In one embodiment, the correction indication information is calculated based on the vertex coordinates in the target image, and it is understood that, under different shooting postures, the vertex coordinates of the projection curtain and the projection screen in the initial image are inconsistent, for example, the posture of the moving device is a preset posture when the initial image in fig. 3 (c) is shot, the projection curtain is at the normal viewing angle of the audience, at this time, the upper left vertex of the projection curtain is located at the upper left corner of the initial image, but when the moving device is shot in other shooting postures, the initial image in fig. 3 (a) and fig. 3 (b) is obtained, the upper left vertex of the projection curtain is not located at the upper left corner of the initial image, so that in order to obtain the correction indication information, the positions of the vertices of the projection curtain and the projection screen need to be identified, which results in a certain complexity for the relevant calculation of the vertex coordinates, and thus also increases the complexity of the process of calculating the correction indication information. It will be appreciated that if the actual shooting attitude does not match the preset shooting attitude, the initial image may be controlled to rotate to obtain the target image, and specifically, the initial image may be controlled to rotate by a multiple of 90 degrees to obtain the target image. For example, the initial image in fig. 3 (a) is rotated clockwise by 90 degrees to obtain a target image; the initial image in fig. 3 (b) is rotated counterclockwise by 90 degrees to obtain a target image. By rotating the initial image into the target image, a foundation is laid for unified processing of vertex coordinate related computation, and the processing process of obtaining correction instruction information by utilizing the target image conforming to the preset shooting gesture can be unified, so that different processing flows do not need to be executed for different actual shooting gestures, the complexity of related computation is reduced, and the computation efficiency is improved.

In one embodiment, the first projection screen is a projection screen that is scaled and projected by a projector at a preset scaling rate, and the server may perform coordinate conversion calculation based on a first vertex coordinate of the first projection screen in the target image under the image coordinate system, a second vertex coordinate of the projection curtain under the image coordinate system, and the preset scaling rate, so as to obtain a target vertex coordinate of the projection curtain under the target coordinate system, and use the target vertex coordinate as the correction instruction information. The preset scaling rate can be 50%, 60% or 70% or the like, so that the first projection picture is ensured to be in the projection curtain. It is understood that the preset scaling rate may be other values, which are not limited thereto.

In one embodiment, the server may remove the plurality of feature patterns in the first projection frame in the image to obtain the first projection frame with a solid color. The server may perform contour edge detection on the first projection screen and the projection curtain of the solid color to obtain a contour image, and determine a first vertex coordinate and a second vertex coordinate based on the contour image.

In one embodiment, the server may clear the feature pattern in the first projection screen by a geometric area that can overlay the feature pattern and is located within the first projection screen.

In one embodiment, the feature pattern is circular; the geometric area is a rectangular area. The server may determine the coordinates and radius of the graphic center point of each of the plurality of circles and obtain the rectangular area based on the radius and the coordinates.

According to the projection picture correction method, an initial image shot by the mobile equipment aiming at a projection curtain is acquired; the first projection screen projected by the projector is displayed in the projection curtain in the initial image. The first projection picture displays a plurality of characteristic patterns. The positions of the plurality of feature patterns in the initial image correspond to a shooting pose of the mobile device. Position information of a plurality of feature patterns in an initial image is determined, and an actual shooting pose when the mobile device shoots the initial image is determined based on the position information. And if the actual shooting gesture does not accord with the preset shooting gesture, controlling the rotation of the initial image to obtain a target image. Therefore, the shooting image shot in the preset shooting posture can be obtained without installing a camera on the projector, the hardware cost is reduced, shooting can be performed in any posture, and therefore complexity is reduced, and flexibility is improved. Correction instruction information is acquired based on the target image. Therefore, the target image accords with the preset shooting gesture, the processing process of acquiring the correction instruction information is consistent, the complexity of the correlation calculation of the correction instruction information is reduced, and the calculation efficiency is improved. And transmitting correction instruction information to the projector so that the projector corrects the projected second projection screen to align with the projection curtain based on the correction instruction information. Therefore, under the conditions that the projector has no hardware requirement and the actual shooting posture of the initial image has no requirement, the automatic identification of the actual shooting posture is realized, the target image which accords with the preset shooting posture is obtained, and the correction is completed based on the target image, so that the flexibility is improved.

In one embodiment, the number of feature patterns is N; determining the position information of the characteristic pattern in the initial image, and determining the actual shooting pose of the mobile device when shooting the initial image based on the position information comprises: identifying a target graph which is the same as the shape of the characteristic pattern in the initial image; the target pattern includes at least a feature pattern; respectively calculating distances from the graphic center points of the plurality of target graphics to the center points of the initial images; screening N graphic center points with distances meeting preset conditions from the graphic center points of a plurality of target graphics to obtain the graphic center points of each characteristic pattern in a first projection picture; and determining the actual shooting gesture of the mobile device when the mobile device shoots the initial image according to the position information of the graphic center point of the screened characteristic pattern.

Specifically, the number of feature patterns is N, which is a natural number greater than 2. The server may identify a target pattern in the initial image that is the same as the shape of the feature pattern. Wherein the target pattern comprises at least a feature pattern. The server calculates distances from the graphics center points of the plurality of target graphics to the center points of the initial image, respectively. And the server screens out N graphic center points with the distances meeting preset conditions from the graphic center points of the plurality of target graphics to obtain the graphic center points of the characteristic patterns in the first projection picture. And the server determines the actual shooting gesture of the mobile device when shooting the initial image according to the position information of the graphic center point of the screened characteristic pattern.

In one embodiment, the server may screen the effective distance based on the distances corresponding to the plurality of target graphics, and screen N graphics center points with the distance smaller than the effective distance, to obtain the graphics center points of each feature pattern in the first projection image.

In one embodiment, the server may perform edge detection on the target image to obtain a contour image. And determining the minimum distance from the center point of the target image to the edge of the projection picture in the contour image, and taking the minimum distance as the effective distance.

In another embodiment, the server may sort the distances corresponding to the plurality of target patterns in order from small to large, and use the top N number of target patterns as the feature patterns.

In this embodiment, the number of feature patterns is N, and the server may screen N target patterns whose distances satisfy the preset condition from a plurality of target patterns having the same shape as the feature patterns, to obtain a plurality of feature patterns. Therefore, even if the periphery of the projection curtain is provided with other patterns with the same shape as the characteristic patterns, the interference of the other patterns on the characteristic pattern determination process can be avoided, so that the anti-interference capability is improved, and the use requirement on the projector is reduced.

In one embodiment, the correction instruction information is the target vertex coordinates of the projection curtain in the target coordinate system; the first projection picture is a projection picture which is zoomed and projected by the projector at a preset zoom rate; acquiring correction instruction information based on the target image includes: determining a first vertex coordinate of a first projection picture in a target image under an image coordinate system and a second vertex coordinate of a projection curtain under the image coordinate system; and carrying out coordinate conversion calculation based on the first vertex coordinates, the second vertex coordinates and a preset scaling rate to obtain target vertex coordinates of the projection curtain under a target coordinate system.

The image coordinate system is a coordinate system corresponding to the target image. The first vertex coordinates are coordinates of vertices of the first projection screen in the image coordinate system. The second vertex coordinates are coordinates of the vertices of the projection curtain in the image coordinate system. The target vertex coordinates are coordinates of the vertices of the projection curtain in the target coordinate system.

Specifically, the correction instruction information is the target vertex coordinates of the projection curtain under the target coordinate system; the first projection screen is a projection screen which is subjected to scaling projection by the projector at a preset scaling rate. The server can determine a first vertex coordinate of a first projection picture in the target image under the image coordinate system and a second vertex coordinate of the projection curtain under the image coordinate system. The server can perform coordinate conversion calculation based on the first vertex coordinates, the second vertex coordinates and a preset scaling rate to obtain target vertex coordinates of the projection curtain under a target coordinate system.

In one embodiment, the preset resolution includes a preset vertical resolution and a preset horizontal resolution, and the length and width of a rectangle formed by the vertex coordinates of the four original projection pictures in the projector coordinate system are respectively the preset horizontal resolution and the preset vertical resolution. Similarly, the length and width of the rectangle formed by the vertex coordinates of the projection curtain under the plane coordinate system of the projection curtain are respectively the preset horizontal resolution and the preset vertical resolution. For example, the preset vertical resolution and the preset horizontal resolution are 1920 and 1080, respectively, and the vertex coordinates of the four original projection pictures in the projector coordinate system are (0, 0), (1920,0), (0, 1080), (1920, 1080), respectively. The four vertex coordinates of the projection curtain in the planar coordinate system are (0, 0), (1920,0), (0, 1080), (1920, 1080), respectively.

In one embodiment, the step of performing coordinate conversion calculation based on the first vertex coordinates, the second vertex coordinates and a preset scaling factor to obtain target vertex coordinates of the projection curtain in a target coordinate system is performed based on a preset resolution; the server sends the target vertex coordinates to the projector, so that the projector converts the target vertex coordinates according to the conversion relation between the self resolution and the preset resolution, and corrects the projected second projection picture and the projection curtain based on the converted target vertex coordinates.

In one embodiment, the projector includes a short-focus projector and a long-focus projector. And if the projector is a short-focus projector, performing coordinate conversion calculation on the first vertex coordinates of the projection curtain in the target image to obtain target vertex coordinates of the projection curtain under a projector coordinate system. And if the projector is a tele projector, performing coordinate conversion calculation on the first vertex coordinates of the projection curtain in the target image to obtain target vertex coordinates of the projection curtain under a projection curtain plane coordinate system.

In this embodiment, the server may obtain the target vertex coordinate of the projection curtain under the target coordinate system based on the first vertex coordinate of the first projection screen under the image coordinate system in the target image, the second vertex coordinate of the projection curtain under the image coordinate system, and the preset scaling, and use the target vertex coordinate as the correction instruction information. Compared with other types of correction instruction information, the method has the advantages that the target vertex coordinates are used as the correction instruction information, so that the projector can obtain accurate correction offset, and the correction accuracy of a projection picture is improved.

In one embodiment, determining a first vertex coordinate of a first projected screen in the target image in the image coordinate system and a second vertex coordinate of the projected screen in the image coordinate system includes: clearing the displayed multiple characteristic patterns in the initial image or the target image so that a first projection picture of the initial image is solid; performing contour edge detection on a first projection picture and a projection curtain of pure colors in an initial image or a target image to obtain a contour image; and determining a first vertex coordinate of a first projection picture in the target image under the image coordinate system and a second vertex coordinate of the projection curtain under the image coordinate system based on the contour image.

Specifically, the server may clear the displayed plurality of feature patterns in the initial image or the target image so that the first projection screen of the initial image is solid. The server can detect the contour edge of the first projection picture and the projection curtain of the solid color in the initial image or the target image to obtain a contour image. The server may determine, based on the contour image, a first vertex coordinate of a first projection screen in the target image in the image coordinate system and a second vertex coordinate of the projection curtain in the image coordinate system. It will be appreciated that after the feature pattern in the first projection screen is cleared, the edge of the feature pattern can be prevented from being identified as vertex coordinates.

As shown in fig. 4, the contour image includes a screen contour edge of the projection screen and a screen contour edge of the projection screen. Since the pixel values of the black part are 0 and the pixel values of the white part are 255, the server can determine the vertex of the contour edge of the picture in the contour image according to the pixel values of the pixel points to obtain the first vertex coordinate of the projection picture under the image coordinate system, and determine the vertex of the contour edge of the screen in the contour image to obtain the second vertex coordinate of the projection curtain under the image coordinate system.

In this embodiment, the contour edge detection is performed by using the first projection screen with solid color to obtain a contour image, and the first vertex coordinate and the second vertex coordinate are obtained based on the contour image, so that the determination of the vertex coordinate is prevented from being interfered by other interference objects, and the accuracy of the judgment of the vertex coordinate is improved.

In one embodiment, clearing the displayed plurality of feature patterns in the initial image or the target image such that the first projected picture of the initial image is solid comprises: determining a geometric figure area which covers the characteristic pattern and is positioned in the first projection picture; the pixel values of the pixel points in the geometric figure area are modified to clear the displayed characteristic pattern in the initial image, so that the projection picture of the initial image is solid.

In particular, the server may determine a geometric area that covers the characteristic pattern and is located within the first projection screen. Further, the server modifies pixel values of pixel points within the geometric area to clear the displayed feature pattern in the initial image so that the projected picture of the initial image is solid.

In this embodiment, by using the geometric area that covers the feature pattern and is located in the first projection screen to remove the feature pattern, it is not necessary to remove each feature pattern one by one, so that the feature pattern removing process is simplified.

In one embodiment, the feature pattern is circular; the geometric figure area is a rectangular area; determining a geometric area covering the characteristic pattern and located within the projected picture includes: determining the coordinates and the radius of the graphics center point of each of the circles; determining a rectangular area covering a plurality of circles according to the radius and the coordinates of the graphic center point; the length of the sides of the rectangular area is greater than or equal to the diameter of the circle.

Specifically, the feature pattern is circular, and the geometric area is a rectangular area. The server may determine coordinates and radii of the graphic center points of the respective circles and determine rectangular areas covering the circles according to the radii and the coordinates of the graphic center points. Wherein the side length of the rectangular region is greater than or equal to the diameter of the circle.

In this embodiment, when the feature pattern is a circle, the rectangular area with the side length greater than or equal to the diameter of the circle is determined by the coordinates and the radius of the center point of the respective graph of the circle, so that the edge of the first projection screen is prevented from being removed due to the overlarge rectangular area, and the accuracy of removal is improved.

In one embodiment, the number of the feature patterns is three, and the central points of the three feature patterns form a right triangle; modifying pixel values for pixel points within the geometric area includes: determining first center point coordinates of the graphics center points of the three feature patterns; determining second center point coordinates of a fourth graphic center point based on the three first center point coordinates; the second center point coordinates and the three first center point coordinates form a rectangular quadrilateral; calculating the average of the second center point coordinates and the three first center point coordinates to obtain average center point coordinates; the pixel values of the pixel points within the geometric area are modified to the pixel values at the average center point coordinates.

Specifically, the number of the feature patterns is three, and the center points of the three feature patterns form a right triangle shape. The server may determine first center point coordinates of the graphic center points of each of the three feature patterns and determine second center point coordinates of the fourth graphic center point based on the three first center point coordinates. Wherein the second center point coordinates and the three first center point coordinates form a rectangular quadrilateral. And the server calculates the average of the second center point coordinates and the three first center point coordinates to obtain the average center point coordinates. Further, the server modifies the pixel values of the pixel points within the geometric area to pixel values at the average center point coordinates.

In this embodiment, the pixel value at the average center point is used as the pixel value after erasing, so that the first projection picture can have the same or similar pixel value, and abnormal edges are avoided in the edge detection process due to different pixel values in the first projection picture, thereby improving the accuracy of the edge detection result.

In particular, the resting surface may be horizontal, such as a table top, floor, countertop; the placement surface may be vertical, such as a wall surface.

In one embodiment, the projector and projection screen may be positioned adjacent to one another on a placement surface. In this way, the projection light source length of the projector can be greatly reduced.

In one embodiment, the server may be a cloud server. The mobile device is a mobile phone, and Bluetooth is used for connection between the mobile phone and the projector. The projector can be an ultra-short focal projector and is arranged on one side of the edge of the projection curtain through a bracket; or the projector is a desktop projector and is directly arranged on one side of the edge of the projection curtain. After the projector is started by a user, the projector projects a first projection picture with a plurality of characteristic patterns on a projection curtain. The user controls the mobile phone camera to shoot a projection curtain containing the characteristic patterns, and the initial shot image is transmitted to the cloud server. The first projection picture projected by the projector is displayed in the projection curtain in the initial image, and the positions of the plurality of characteristic patterns in the initial image correspond to the shooting gesture of the mobile device. The cloud server acquires an initial image, determines position information of a plurality of characteristic patterns in the initial image, and determines an actual shooting gesture of the mobile device when shooting the initial image based on the position information. If the actual shooting gesture does not accord with the preset shooting gesture, the cloud server controls the initial image to rotate so as to obtain a target image. The correction instruction information is acquired based on the target image, and the correction instruction information is transmitted to the projector, so that the projector corrects the projected second projection picture and the projection curtain based on the correction instruction information. In this embodiment, with a preset scaling factor of 60% and a preset resolution of 1920×1080 as the calculation parameters, the corresponding detailed processing steps are as follows:

a) And opening the Bluetooth of the mobile phone, selecting equipment connection, and establishing communication connection between the mobile phone equipment and the projector.

b) The application program or the applet first page is clicked to click a shooting screen to trigger the camera function of the mobile phone, so that the mobile phone can be used for shooting a projection curtain and a projection picture in a horizontal screen or a vertical screen and standing at any angle.

c) The projector projects a first projection picture with a plurality of characteristic patterns, the size of which is reduced to 60%, in the projection curtain, and then the projection picture on the projection curtain is photographed.

d) And the mobile phone transmits the shot initial image to a cloud server, and the cloud server calls an Opencv computer vision software library to perform picture preprocessing. Converting the initial image into a gray level image, and then calling a Gaussian filter function in Opencv to reduce noise of the initial image to obtain a preprocessed initial image.

e) And judging the actual shooting gesture of the mobile phone when shooting by using the position information of the characteristic pattern, and then performing rotation operation on the initial image preprocessed in the previous step (namely converting the horizontal screen shooting direction picture into the vertical screen shooting direction picture) to obtain a target image conforming to the preset shooting gesture.

f) And (3) performing edge detection on the target image in the last step by using a Canny function (edge detection function) in Opencv to obtain a contour image.

g) And 4 first vertex coordinates of a 60% projection picture and 4 second vertex coordinates of a projection curtain in a picture coordinate system are calculated.

h) And (3) the coordinate system conversion matrix M1 is calculated by using the 4 first vertex coordinates of the projection curtain under the picture coordinate system and the 4 vertex coordinates (0, 0), (1920,0), (0, 1080), (1920, 1080) of the projection curtain under the plane coordinate system, and the perspective transformation getPerspolectransform of Opencv is called, namely M1 is the coordinate conversion relation from the picture coordinate system to the plane coordinate system, namely the image coordinate system and the plane coordinate system.

i) And multiplying the first vertex coordinates of the 4 images of the 60% image in the image coordinate system by the conversion matrix M1 to obtain the vertex coordinates of the 4 images of the 60% image in the plane coordinate system, and then using the vertex coordinates of the 4 images of the 60% image in the plane coordinate system to calculate the vertex coordinates of the 4 images of the 100% image in the plane coordinate system.

j) The coordinate system conversion matrix M2 is calculated by invoking the perspective transformation getpermectransform of Opencv from the 4 vertex coordinates of the 100% picture under the plane coordinate system to the 4 vertex coordinates (0, 0), (1920,0), (0, 1080), (1920, 1080) of the 100% picture under the projector coordinate system, that is, M2 is the target coordinate conversion relation of the plane coordinate system and the projector coordinate system.

k) And finally, multiplying the projection curtain coordinates (0, 0), (1920,0), (0, 1080), (1920, 1080) in the plane coordinate system by M2 to obtain the projection curtain coordinates, namely the target vertex coordinates, in the projector coordinate system.

l) transmitting the vertex coordinates of 4 targets of the projection curtain under the projector coordinate system to the mobile phone end by the cloud server, and transmitting the vertex coordinates to the projector equipment by the mobile phone end, wherein the projector equipment carries out four-point trapezoidal correction according to the vertex coordinates of the targets so that the picture is completely projected into the projection curtain range, and thus the automatic correction function of the projection curtain can be completed.

In one embodiment, as shown in fig. 5, a projection screen correction method is provided, where the method is applied to a mobile device for illustration, it is understood that the method may also be applied to a server, and may also be applied to a system including the mobile device and the server, and implemented through interaction between the mobile device and the server. In this embodiment, the method includes the steps of:

s502, shooting a projection curtain to obtain an initial image; a first projection picture projected by a projector is displayed in a projection curtain in the initial image; a plurality of characteristic patterns are displayed in the first projection picture; the positions of the plurality of feature patterns in the initial image correspond to a shooting pose of the mobile device.

Specifically, the mobile device shoots a projection curtain to obtain an initial image. The first projection picture projected by the projector is displayed in the projection curtain in the initial image, a plurality of characteristic patterns are displayed in the first projection picture, and the positions of the characteristic patterns in the initial image correspond to the shooting gesture of the mobile device.

S504, sending the initial image to a server, triggering the server to determine the position information of a plurality of characteristic patterns in the initial image, and determining the actual shooting gesture when shooting the initial image based on the position information; if the actual shooting gesture does not accord with the preset shooting gesture, controlling the rotation of the initial image to obtain a target image; acquiring correction instruction information based on the target image; and transmits correction instruction information.

Specifically, the mobile device may send an initial image to the server, and the server determines position information of a plurality of feature patterns in the initial image after receiving the initial image, and determines an actual shooting pose when shooting the initial image based on the position information. If the actual shooting gesture does not accord with the preset shooting gesture, the server controls the initial image to rotate so as to obtain a target image, acquires correction instruction information based on the target image, and sends the correction instruction information to the mobile device.

S506, receiving the correction instruction information and transmitting the correction instruction information to the projector, so that the projector corrects the projected second projection screen to align with the projection screen based on the correction instruction information.

Specifically, the mobile device receives the correction instruction information and transmits the correction instruction information to the projector. The projector performs correction based on the received correction instruction information so that the projected second projection screen and the projection curtain are aligned.

In one embodiment, as shown in fig. 6, a projection screen correction method is provided, and this embodiment is exemplified by the application of the method to a projector, and the method includes the following steps:

s602, projecting a first projection picture in a projection curtain; a plurality of characteristic patterns are displayed in the first projection picture; the positions of the plurality of feature patterns in the initial image correspond to a shooting pose of the mobile device.

Specifically, the projector projects a first projection image in the projection curtain. Wherein, a plurality of characteristic patterns are displayed in the first projection picture; the positions of the plurality of feature patterns in the initial image correspond to a shooting pose of the mobile device.

S604, acquiring correction instruction information; the correction instruction information is obtained based on the target image; the target image is obtained by controlling an initial image obtained by shooting a projection curtain to rotate under the condition that the actual shooting gesture is not consistent with the preset shooting gesture; the actual shooting attitude is obtained from the positional information of the plurality of feature patterns in the initial image.

Specifically, the projector acquires correction instruction information. Wherein the correction instruction information is obtained based on the target image. The target image is obtained by controlling an initial image obtained by shooting a projection curtain to rotate under the condition that the actual shooting gesture is not consistent with the preset shooting gesture; the actual shooting attitude is obtained from the positional information of the plurality of feature patterns in the initial image.

And S606, correcting based on the correction instruction information to align the projected second projection picture with the projection curtain.

Specifically, the projector performs correction based on the correction instruction information to align the projected second projection screen and the projection curtain.

It should be understood that, although the steps in the flowcharts in some embodiments of the present application are shown in order as indicated by the arrows, these steps are not necessarily performed in order as indicated by the arrows. The steps are not strictly limited to the order of execution unless explicitly recited herein, and the steps may be executed in other orders. Moreover, at least a portion of the steps in the flowcharts may include a plurality of steps or stages that are not necessarily performed at the same time, but may be performed at different times, and the order of execution of the steps or stages is not necessarily sequential, but may be performed in rotation or alternately with at least a portion of the steps or stages in other steps or other steps.

Based on the same inventive concept, the embodiment of the application also provides a projection screen correction device for realizing the above-mentioned projection screen correction method. The implementation of the solution provided by the apparatus is similar to that described in the above method, so the specific limitation in the embodiments of the projection screen correction apparatus provided below may be referred to the limitation of the projection screen correction method hereinabove, and will not be repeated herein.

In one embodiment, as shown in fig. 7, there is provided a projection screen correction apparatus 700 including: an image acquisition module 702, an image rotation module 704, and a correction module 706, wherein:

an image acquisition module 702 for acquiring an initial image taken by the mobile device for the projection curtain; a first projection picture projected by a projector is displayed in a projection curtain in the initial image; a plurality of characteristic patterns are displayed in the first projection picture; the positions of the plurality of feature patterns in the initial image correspond to a shooting pose of the mobile device.

An image rotation module 704, configured to determine position information of a plurality of feature patterns in an initial image, and determine an actual shooting pose when the mobile device shoots the initial image based on the position information; and if the actual shooting gesture does not accord with the preset shooting gesture, controlling the rotation of the initial image to obtain a target image.

A correction module 706, configured to obtain correction instruction information based on the target image, and send the correction instruction information to the projector, so that the projector corrects the projected second projection screen and the projection curtain based on the correction instruction information.

In one embodiment, the number of feature patterns is N; the image rotation module 704 is further configured to identify a target graphic in the initial image that is identical to the feature pattern in shape; the target pattern includes at least a feature pattern; respectively calculating distances from the graphic center points of the plurality of target graphics to the center points of the initial images; screening N graphic center points with distances meeting preset conditions from the graphic center points of a plurality of target graphics to obtain the graphic center points of each characteristic pattern in a first projection picture; and determining the actual shooting gesture of the mobile device when the mobile device shoots the initial image according to the position information of the graphic center point of the screened characteristic pattern.

In one embodiment, the correction instruction information is the target vertex coordinates of the projection curtain in the target coordinate system; the first projection picture is a projection picture which is zoomed and projected by the projector at a preset zoom rate; the correction module 706 is further configured to determine a first vertex coordinate of the first projection screen in the target image under the image coordinate system and a second vertex coordinate of the projection screen in the image coordinate system; and carrying out coordinate conversion calculation based on the first vertex coordinates, the second vertex coordinates and a preset scaling rate to obtain target vertex coordinates of the projection curtain under a target coordinate system.

In one embodiment, the correction module 706 is further configured to clear the displayed plurality of feature patterns in the initial image or the target image such that the first projected screen of the initial image is solid; performing contour edge detection on a first projection picture and a projection curtain of pure colors in an initial image or a target image to obtain a contour image; and determining a first vertex coordinate of a first projection picture in the target image under the image coordinate system and a second vertex coordinate of the projection curtain under the image coordinate system based on the contour image.

In one embodiment, the correction module 706 is further configured to determine a geometric region that covers the characteristic pattern and is located within the first projection screen; the pixel values of the pixel points in the geometric figure area are modified to clear the displayed characteristic pattern in the initial image, so that the projection picture of the initial image is solid.

In one embodiment, the feature pattern is circular; the geometric figure area is a rectangular area; the correction module 706 is further configured to determine coordinates and radii of the graphics center points of each of the plurality of circles; determining a rectangular area covering a plurality of circles according to the radius and the coordinates of the graphic center point; the length of the sides of the rectangular area is greater than or equal to the diameter of the circle.

In one embodiment, the number of the feature patterns is three, and the central points of the three feature patterns form a right triangle; the correction module 706 is further configured to determine first center point coordinates of graphics center points of each of the three feature patterns; determining second center point coordinates of a fourth graphic center point based on the three first center point coordinates; the second center point coordinates and the three first center point coordinates form a rectangular quadrilateral; calculating the average of the second center point coordinates and the three first center point coordinates to obtain average center point coordinates; the pixel values of the pixel points within the geometric area are modified to the pixel values at the average center point coordinates.

The projection screen correction device acquires an initial image shot by the mobile device for a projection curtain; the first projection screen projected by the projector is displayed in the projection curtain in the initial image. The first projection picture displays a plurality of characteristic patterns. The positions of the plurality of feature patterns in the initial image correspond to a shooting pose of the mobile device. Position information of a plurality of feature patterns in an initial image is determined, and an actual shooting pose when the mobile device shoots the initial image is determined based on the position information. And if the actual shooting gesture does not accord with the preset shooting gesture, controlling the rotation of the initial image to obtain a target image. Therefore, the shooting image shot in the preset shooting posture can be obtained without installing a camera on the projector, the hardware cost is reduced, shooting can be performed in any posture, and therefore complexity is reduced, and flexibility is improved. Correction instruction information is acquired based on the target image. Therefore, the target image accords with the preset shooting gesture, the processing process of acquiring the correction instruction information is consistent, the complexity of the correlation calculation of the correction instruction information is reduced, and the calculation efficiency is improved. And transmitting correction instruction information to the projector so that the projector corrects the projected second projection screen to align with the projection curtain based on the correction instruction information. Therefore, under the conditions that the projector has no hardware requirement and the actual shooting posture of the initial image has no requirement, the automatic identification of the actual shooting posture is realized, the target image which accords with the preset shooting posture is obtained, and the correction is completed based on the target image, so that the flexibility is improved.

In one embodiment, as shown in fig. 8, there is provided a projection screen correction apparatus 800 including: a shooting module 802, a sending module 804, and a receiving module 806, wherein:

the shooting module 802 is configured to shoot the projection curtain to obtain an initial image; a first projection picture projected by a projector is displayed in a projection curtain in the initial image; a plurality of characteristic patterns are displayed in the first projection picture; the positions of the plurality of feature patterns in the initial image correspond to the shooting pose of the mobile device;

the sending module 804 is configured to send an initial image to a correction cloud, trigger the correction cloud to determine location information of a plurality of feature patterns in the initial image, and determine an actual shooting gesture when shooting the initial image based on the location information; if the actual shooting gesture does not accord with the preset shooting gesture, controlling the rotation of the initial image to obtain a target image; acquiring correction instruction information based on the target image; and transmitting correction instruction information;

a receiving module 806, configured to receive the correction instruction information and send the correction instruction information to the projector, so that the projector corrects the projected second projection screen and the projection curtain based on the correction instruction information.

In one embodiment, as shown in fig. 9, there is provided a projection screen correction apparatus 900 including: a projection module 902, an acquisition module 904, and a correction module 906, wherein:

the projection module 902 is configured to project a first projection screen onto a projection curtain; a plurality of characteristic patterns are displayed in the first projection picture; the positions of the plurality of feature patterns in the initial image correspond to the shooting pose of the mobile device;

an obtaining module 904, configured to obtain correction instruction information; the correction instruction information is obtained based on the target image; the target image is obtained by controlling an initial image obtained by shooting a projection curtain to rotate under the condition that the actual shooting gesture is not consistent with the preset shooting gesture; the actual shooting gesture is obtained according to the position information of a plurality of characteristic patterns in the initial image;

a correction module 906, configured to perform correction based on the correction instruction information to align the projected second projection screen and the projection curtain.

For specific limitations of the above projection screen correction apparatus, reference may be made to the above limitations of the above projection screen correction method, and no further description is given here. The above-described respective modules in the projection screen correction apparatus may be implemented in whole or in part by software, hardware, or a combination thereof. The above modules may be embedded in hardware or may be independent of a processor in the computer device, or may be stored in software in a memory in the computer device, so that the processor may call and execute operations corresponding to the above modules.

In one embodiment, a computer device is provided, which may be a server, and the internal structure of which may be as shown in fig. 10. The computer device includes a processor, a memory, an Input/Output interface (I/O) and a communication interface. The processor, the memory and the input/output interface are connected through a system bus, and the communication interface is connected to the system bus through the input/output interface. Wherein the processor of the computer device is configured to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, computer programs, and a database. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage media. The input/output interface of the computer device is used to exchange information between the processor and the external device. The communication interface of the computer device is used for communicating with an external terminal through a network connection. The computer program is executed by a processor to implement a projection screen correction method.

In one embodiment, a computer device is provided, which may be a mobile device, the internal structure of which may be as shown in fig. 11. The computer device includes a processor, a memory, an input/output interface, a communication interface, a display unit, and an input means. The processor, the memory and the input/output interface are connected through a system bus, and the communication interface, the display unit and the input device are connected to the system bus through the input/output interface. Wherein the processor of the computer device is configured to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage media. The input/output interface of the computer device is used to exchange information between the processor and the external device. The communication interface of the computer device is used for carrying out wired or wireless communication with an external terminal, and the wireless mode can be realized through WIFI, a mobile cellular network, NFC (near field communication) or other technologies. The computer program is executed by a processor to implement a projection screen correction method. The display unit of the computer equipment is used for forming a visual picture, and can be a display screen, a projection device or a virtual reality imaging device, wherein the display screen can be a liquid crystal display screen or an electronic ink display screen, the input device of the computer equipment can be a touch layer covered on the display screen, can also be a key, a track ball or a touch pad arranged on a shell of the computer equipment, and can also be an external keyboard, a touch pad or a mouse and the like.

It will be appreciated by those skilled in the art that the structures shown in fig. 10 and 11 are block diagrams of only some of the structures associated with the present application and are not intended to limit the computer device to which the present application may be applied, and that a particular computer device may include more or fewer components than shown, or may combine certain components, or have a different arrangement of components.

In an embodiment, there is also provided a computer device comprising a memory and a processor, the memory having stored therein a computer program, the processor implementing the steps of the method embodiments described above when the computer program is executed.

In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored which, when executed by a processor, carries out the steps of the method embodiments described above.

In an embodiment, a computer program product is provided, comprising a computer program which, when executed by a processor, implements the steps of the method embodiments described above.

Those skilled in the art will appreciate that implementing all or part of the above-described methods in accordance with the embodiments may be accomplished by way of a computer program stored on a non-transitory computer readable storage medium, which when executed may comprise the steps of the embodiments of the methods described above. Any reference to memory, storage, database, or other medium used in embodiments provided herein may include at least one of non-volatile and volatile memory. The nonvolatile Memory may include Read-Only Memory (ROM), magnetic tape, floppy disk, flash Memory, optical Memory, or the like. Volatile memory can include random access memory (Random Access Memory, RAM) or external cache memory. By way of illustration, and not limitation, RAM can be in the form of a variety of forms, such as static random access memory (Static Random Access Memory, SRAM) or dynamic random access memory (Dynamic Random Access Memory, DRAM), and the like.

The technical features of the above embodiments may be arbitrarily combined, and all possible combinations of the technical features in the above embodiments are not described for brevity of description, however, as long as there is no contradiction between the combinations of the technical features, they should be considered as the scope of the description.

The foregoing examples represent only a few embodiments of the present application, which are described in more detail and are not to be construed as limiting the scope of the invention. It should be noted that it would be apparent to those skilled in the art that various modifications and improvements could be made without departing from the spirit of the present application, which would be within the scope of the present application. Accordingly, the scope of protection of the present application is to be determined by the claims appended hereto.

Claims

1. A projection screen correction method, the method comprising:

acquiring an initial image shot by the mobile device for a projection curtain; a first projection picture projected by a projector is displayed in a projection curtain in the initial image; a plurality of characteristic patterns are displayed in the first projection picture, wherein the number of the characteristic patterns is N; the positions of the plurality of feature patterns in the initial image correspond to shooting attitudes of the mobile device;

Identifying a target graph which is the same as the shape of the characteristic pattern in the initial image; the target graph at least comprises the characteristic pattern; respectively calculating distances from the graphic center points of the plurality of target graphics to the center points of the initial images; screening N graphic center points with distances meeting preset conditions from the graphic center points of a plurality of target graphics to obtain the graphic center points of each characteristic pattern in the first projection picture; determining the actual shooting gesture of the mobile equipment when shooting the initial image according to the position information of the graphic center point of the screened characteristic pattern;

2. The method of claim 1, wherein the correction indicating information is a target vertex coordinate of the projection curtain in a target coordinate system; the first projection picture is a projection picture which is subjected to scaling projection by the projector at a preset scaling rate; the acquiring correction instruction information based on the target image includes:

3. The method of claim 2, wherein the determining a first vertex coordinate of the first projected picture in the target image in an image coordinate system and a second vertex coordinate of a projection screen in the image coordinate system comprises:

4. The method of claim 3, wherein said clearing the displayed plurality of the feature patterns in the initial image or the target image such that the first projected picture of the initial image is solid comprises:

5. The method of claim 4, wherein the pattern of features is circular; the geometric figure area is a rectangular area; the determining a geometric area that covers the feature pattern and is located within the projection screen includes:

determining a rectangular area covering a plurality of circles according to the radius and the coordinates of the graphic center point; the side length of the rectangular region is greater than or equal to the diameter of the circle.

6. The method of claim 4, wherein the number of the feature patterns is three, and the center points of the three feature patterns form a right triangle shape; the modifying pixel values of pixel points within the geometric area includes:

7. The method of claim 1, wherein the projector and the projection screen are disposed on a same placement surface.

8. A projection screen correction apparatus, the apparatus comprising:

the image rotation module is used for identifying a target graph which is the same as the characteristic pattern in the initial image; the target graph at least comprises the characteristic pattern; respectively calculating distances from the graphic center points of the plurality of target graphics to the center points of the initial images; screening N graphic center points with distances meeting preset conditions from the graphic center points of a plurality of target graphics to obtain the graphic center points of each characteristic pattern in the first projection picture; determining the actual shooting gesture of the mobile equipment when shooting the initial image according to the position information of the graphic center point of the screened characteristic pattern; if the actual shooting gesture does not accord with the preset shooting gesture, controlling the initial image to rotate so as to obtain a target image;

9. The apparatus of claim 8, wherein the correction module is further configured to determine a first vertex coordinate of the first projected screen in the target image in an image coordinate system and a second vertex coordinate of a projection curtain in the image coordinate system;

and carrying out coordinate conversion calculation based on the first vertex coordinates, the second vertex coordinates and a preset scaling rate to obtain target vertex coordinates of the projection curtain under a target coordinate system.

10. A projection screen correction method, the method comprising:

shooting a projection curtain to obtain an initial image; a first projection picture projected by a projector is displayed in a projection curtain in the initial image; a plurality of characteristic patterns are displayed in the first projection picture; the positions of the plurality of feature patterns in the initial image correspond to shooting gestures of the mobile device;

The initial image is sent to a server, and the server is triggered to identify a target graph with the same shape as the characteristic pattern in the initial image; the target graph at least comprises the characteristic pattern; respectively calculating distances from the graphic center points of the plurality of target graphics to the center points of the initial images; screening N graphic center points with distances meeting preset conditions from the graphic center points of a plurality of target graphics to obtain the graphic center points of each characteristic pattern in the first projection picture; determining the actual shooting gesture of the mobile equipment when shooting the initial image according to the position information of the graphic center point of the screened characteristic pattern; if the actual shooting gesture does not accord with the preset shooting gesture, controlling the initial image to rotate so as to obtain a target image; acquiring correction instruction information based on the target image; and transmitting the correction instruction information;

11. A projection screen correction apparatus, the apparatus comprising:

the shooting module is used for shooting the projection curtain to obtain an initial image; a first projection picture projected by a projector is displayed in a projection curtain in the initial image; a plurality of characteristic patterns are displayed in the first projection picture; the positions of the plurality of feature patterns in the initial image correspond to shooting gestures of the mobile device;

the sending module is used for sending the initial image to a correction cloud and triggering the correction cloud to identify a target graph with the same shape as the characteristic pattern in the initial image; the target graph at least comprises the characteristic pattern; respectively calculating distances from the graphic center points of the plurality of target graphics to the center points of the initial images; screening N graphic center points with distances meeting preset conditions from the graphic center points of a plurality of target graphics to obtain the graphic center points of each characteristic pattern in the first projection picture; determining the actual shooting gesture of the mobile equipment when shooting the initial image according to the position information of the graphic center point of the screened characteristic pattern; if the actual shooting gesture does not accord with the preset shooting gesture, controlling the initial image to rotate so as to obtain a target image; acquiring correction instruction information based on the target image; and transmitting the correction instruction information;

12. A projection screen correction method, the method comprising:

projecting a first projection picture in a projection curtain; a plurality of characteristic patterns are displayed in the first projection picture; the positions of the plurality of feature patterns in the initial image correspond to the shooting pose of the mobile device;

acquiring correction indication information; the correction instruction information is obtained based on the target image; the target image is obtained by controlling an initial image obtained by shooting the projection curtain to rotate under the condition that the actual shooting gesture is not consistent with the preset shooting gesture; the actual shooting gesture is obtained according to the position information of the pattern center points of the screened feature patterns, the pattern center points of the feature patterns are obtained by respectively calculating the distances from the pattern center points of a plurality of target patterns to the center point of the initial image, N pattern center points with the distances meeting preset conditions are screened out from the pattern center points of the plurality of target patterns, the target patterns are obtained by identifying target patterns with the same shape as the feature patterns in the initial image, the target patterns at least comprise the feature patterns, and the number of the feature patterns is N;

13. A projection screen correction apparatus, the apparatus comprising:

the projection module is used for projecting the first projection picture in the projection curtain; a plurality of characteristic patterns are displayed in the first projection picture; the positions of the plurality of feature patterns in the initial image correspond to the shooting pose of the mobile device;

the acquisition module is used for acquiring correction instruction information; the correction instruction information is obtained based on the target image; the target image is obtained by controlling an initial image obtained by shooting the projection curtain to rotate under the condition that the actual shooting gesture is not consistent with the preset shooting gesture; the actual shooting gesture is obtained according to the position information of the pattern center points of the screened feature patterns, the pattern center points of the feature patterns are obtained by respectively calculating the distances from the pattern center points of a plurality of target patterns to the center point of the initial image, N pattern center points with the distances meeting preset conditions are screened out from the pattern center points of the plurality of target patterns, the target patterns are obtained by identifying target patterns with the same shape as the feature patterns in the initial image, the target patterns at least comprise the feature patterns, and the number of the feature patterns is N;