Projection apparatus and projection control method

Abstract

The embodiment of the invention provides projection equipment and a projection control method. In the projection process, the projection equipment can detect the projected picture content so as to determine the effective content area and the invalid content area in the picture content. When the picture content comprises the effective content area and the invalid content area, the projection equipment can convert the coordinate of the effective content area into the space coordinate and detect the intersection condition of the human body area and the effective content area under the space coordinate. And executing an anti-eye-shooting process based on detecting that the human body region and the effective content region under the space coordinates have an intersection. And if it is detected that no intersection exists between the human body area and the effective content area under the space coordinates, the anti-eye-shooting process is not executed. Therefore, when the user does not enter the effective content area, the projection equipment does not interrupt the projection process all the time, so that the watching experience of the user is improved.

Description

Technical Field

[0001] The present application relates to the technical field of projection equipment, and in particular to a projection equipment and a projection control method. Background Art

[0002] A projection device is a display device that can project images or videos onto a screen. The projection device can project laser light of a specific color into the projection area and form a specific image through the refraction of an optical lens assembly. Due to the portability of the projection device, users can move it during the projection process to project images or videos in different directions.

[0003] The projection device can project the image content onto the projection surface for the user to view the image content. During the projection process, the user may enter the light source emission area of ​​the projection device, causing the projection light source of the projection device to directly hit the user's eyes and cause damage to the user's eyes. For this reason, the projection device is provided with an anti-eye function. When a human body is detected in the light source emission area, the projection device can turn off the light source until it detects that there is no human body in the light source emission area, and then turn on the light source to protect the user in the light source emission area.

[0004] However, in some special scenarios such as screen projection, the size of the effective image content in the screen content and the light source emission area may be different, that is, only part of the light source emission area may display effective content. When the user enters the light source emission area but does not enter the effective content area, the projection light source will not cause damage to the user's eyes, but the projection device will still trigger the anti-eye function, interrupting the viewing process of other users and affecting the user's viewing experience. Summary of the invention

[0005] The present application provides a projection device and a projection control method to solve the problem in the related art that when a user enters a light source emission area but does not enter a valid content area, the projection device triggers an anti-eye function, thereby interrupting the user's viewing process.

[0006] In a first aspect, some embodiments of the present application provide a projection device, including a light emitting component, an image acquisition device, and a controller. The light emitting component is configured to project image content onto a projection surface; the image acquisition device is configured to acquire a target image from the projection surface; and the controller is configured to:

[0007] In the case where it is detected by the first image detection algorithm that the picture content includes a valid content area and an invalid content area, the coordinates of the valid content area are converted into spatial coordinates; wherein the grayscale values ​​or pixel values ​​of consecutive rows and / or consecutive columns of pixels in the invalid content area are the same, and the grayscale values ​​or pixel values ​​of the pixels are lower than a first threshold;

[0008] If it is detected based on the first human body detection algorithm that there is an intersection between the human body area in the target image and the valid content area under the spatial coordinates, then the anti-eye-shooting process is executed;

[0009] If it is detected based on the first human body detection algorithm that there is no intersection between the human body area in the target image and the valid content area under the spatial coordinates, the anti-eye-shooting process is not executed.

[0010] The above technical solution has the following beneficial effects: during the projection process, the projection device can detect the content of the projected picture to determine the valid content area and the invalid content area in the picture content. When the picture content includes the valid content area and the invalid content area, the projection device can convert the coordinates of the valid content area to the spatial coordinates, and detect the intersection of the human body area and the valid content area under the spatial coordinates. Based on the detection of the intersection between the human body area and the valid content area under the spatial coordinates, the anti-eye-shooting process is executed. Based on the detection of the absence of intersection between the human body area and the valid content area under the spatial coordinates, the anti-eye-shooting process is not executed. This ensures that the projection device will not interrupt the projection process when the user does not enter the valid content area, so as to improve the user's viewing experience.

[0011] In some embodiments, the controller is further configured to:

[0012] Detecting the grayscale value or pixel value of a pixel point in the picture content;

[0013] Based on detecting that the grayscale values ​​or pixel values ​​of at least a first number of consecutive rows and / or at least a first number of consecutive columns of pixels are the same, and the grayscale values ​​or pixel values ​​of the pixels are lower than a first threshold, marking the at least a first number of consecutive rows and / or at least a first number of consecutive columns of pixels as invalid content areas;

[0014] An area other than the invalid content area in the screen content is marked as a valid content area.

[0015] The above technical solution has the following beneficial effects: black edge detection processing is performed on the picture content to detect the invalid content area and the valid content area.

[0016] In some embodiments, based on detecting that the screen content does not include an invalid content area, the controller is further configured to:

[0017] Converting the coordinates of the screen content into space coordinates;

[0018] Based on detecting that there is an intersection between the human body area in the target image and the image content under the spatial coordinates, an anti-eye-shooting process is executed;

[0019] Based on the fact that no intersection exists between the human body area in the target image and the picture content under the spatial coordinates, the anti-eye-shooting process is not executed.

[0020] The above technical solution has the following beneficial effects: if the screen contents are all valid content areas, it is determined whether to execute the anti-glare protection by detecting whether the user enters the screen contents.

[0021] In some embodiments, the spatial coordinates include first spatial coordinates in a first coordinate system corresponding to the image acquisition device. After the controller converts the coordinates of the effective content area into spatial coordinates, the controller is further configured to:

[0022] Performing image binarization processing on the target image to obtain a binary image;

[0023] Detecting a human body region in the binary image;

[0024] Based on detecting that no human body region exists in the binary image, marking that no intersection exists between the human body region in the target image and the valid content region under the first spatial coordinate;

[0025] Based on detecting the existence of a human body region in the binary image, first position information of the human body region is acquired; and based on the first position information and the first spatial coordinates, an intersection of the human body region in the target image and a valid content region under the first spatial coordinates is detected.

[0026] The above technical solution has the following beneficial effects: by performing binarization and contour detection on the image, the user area in the image is determined, thereby detecting whether the user enters the valid content area.

[0027] In some embodiments, a distance sensor is further included, configured to collect a distance image of the projection surface; the spatial coordinates further include a second spatial coordinate in a second coordinate system corresponding to the distance sensor;

[0028] After the controller converts the coordinates of the effective content area into space coordinates, the controller is further configured to:

[0029] Detecting the intersection of the human body area in the distance image and the effective content area under the second space coordinates;

[0030] Based on detecting that there is an intersection between the human body area in the target image and the valid content area under the first spatial coordinate, and / or that there is an intersection between the human body area in the distance image and the valid content area under the second spatial coordinate, executing the anti-eye-shooting process;

[0031] Based on detecting that there is no intersection between the human body area in the target image and the valid content area under the first spatial coordinate, and there is no intersection between the human body area in the distance image and the valid content area under the second spatial coordinate, the anti-eye-shooting process is not executed.

[0032] In some embodiments, the distance sensor is configured to detect a separation distance between the projection device and the user.

[0033] Based on detecting that there is no intersection between the human body area in the target image and the valid content area under the first spatial coordinate, the controller is further configured to:

[0034] Detecting the intersection of the human body area in the distance image and the effective content area under the second space coordinates;

[0035] Based on detecting that there is no intersection between the human body area in the distance image and the valid content area under the second space coordinate, not executing the anti-eye-shooting process;

[0036] Based on detecting that there is an intersection between the human body area in the distance image and the valid content area under the second space coordinates, acquiring the interval distance;

[0037] If the interval distance is less than or equal to the distance threshold, the anti-eye-shooting process is executed; if the interval distance is greater than the distance threshold, the anti-eye-shooting process is not executed.

[0038] The above technical solution has the following beneficial effects: a distance threshold is pre-set to determine the detection reliability of the distance sensor. When the object distance is greater than the distance threshold, it is considered that the distance sensor has not detected the user.

[0039] In some embodiments, the controller performs detection of the intersection of the human body area in the distance image and the valid content area under the second space coordinates, and is specifically configured as follows:

[0040] Acquire an initial distance image; the initial distance image is a distance image collected by the distance sensor after the projection device is turned on;

[0041] Performing background frame difference processing on the range image collected by the range sensor and the initial range image to obtain a foreground image;

[0042] Detecting a human body region in the foreground image;

[0043] Based on detecting that no human body region exists in the foreground image, marking that no intersection exists between the human body region in the distance image and the valid content region under the second space coordinates;

[0044] Based on detecting that there is a human body region in the foreground image, second position information of the human body region is acquired, and the intersection of the human body region in the distance image and the valid content region under the second space coordinates is detected according to the second position information.

[0045] The above technical solution has the following beneficial effects: by performing background frame difference processing on the two distance images, it is possible to obtain whether the user has entered the detection range of the distance sensor in the current state compared with the initial state, thereby detecting whether the user has entered the valid content area.

[0046] In some embodiments, the controller is further configured to:

[0047] Detecting the projection mode of the projection device;

[0048] If the projection mode is a screen projection mode, a step of detecting a grayscale value or a pixel value of a pixel point in the picture content is performed.

[0049] The above technical solution has the following beneficial effects: the projection device detects the effective content area and the invalid content area of ​​the projection area in the projection mode, so as to adaptively turn on the anti-shooting eye function according to the effective picture content.

[0050] In a second aspect, some embodiments of the present application provide a projection control method, which is applied to the above-mentioned projection device, and the method includes:

[0051] In the case where it is detected by the first image detection algorithm that the picture content includes a valid content area and an invalid content area, the coordinates of the valid content area are converted into spatial coordinates; wherein the grayscale values ​​or pixel values ​​of consecutive rows and / or consecutive columns of pixels in the invalid content area are the same, and the grayscale values ​​or pixel values ​​of the pixels are lower than a first threshold;

[0052] If it is detected based on the first human body detection algorithm that there is an intersection between the human body area in the target image acquired by the image acquisition device and the valid content area under the spatial coordinates, the anti-eye-shooting process is executed;

[0053] If it is detected based on the first human body detection algorithm that there is no intersection between the human body area in the target image and the valid content area under the spatial coordinates, the anti-eye-shooting process is not executed. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] In order to more clearly illustrate the technical solution of the present application, the drawings required for use in the embodiments are briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0055] Figure 1 A schematic diagram of a projection scene of a projection device in some embodiments is shown;

[0056] Figure 2 A schematic diagram of the optical path of a projection device in some embodiments is shown;

[0057] Figure 3 A schematic diagram of a circuit architecture of a projection device provided by some embodiments is shown;

[0058] Figure 4 A schematic diagram of the structure of a projection device provided in some embodiments is shown;

[0059] Figure 5 A schematic diagram of the lens structure of a projection device provided in some embodiments is shown;

[0060] Figure 6 A schematic diagram of the structure of a distance sensor and an image acquisition device of a projection device provided in some embodiments is shown;

[0061] Figure 7 A schematic diagram of a system framework for implementing display control of a projection device provided in some embodiments is shown;

[0062] Figure 8 A schematic diagram showing an effective content area in some embodiments;

[0063] Fig. 9 A flowchart of the interaction of various components of a projection device in some embodiments is shown;

[0064] Fig.10 A schematic diagram of a checkerboard chart card in some embodiments is shown;

[0065] Fig.11 A schematic diagram of a doughnut chart card in some embodiments is shown;

[0066] Fig.12 A schematic diagram of a process for obtaining a mapping relationship in some embodiments is shown;

[0067] Fig.13 A schematic diagram showing a user area and a projection area in some embodiments;

[0068] Fig.14 A schematic diagram showing a user area and a projection area in some embodiments;

[0069] Fig.15 A schematic diagram showing a user area and a projection area in some embodiments. DETAILED DESCRIPTION

[0070] The following embodiments are described in detail, and examples thereof are shown in the accompanying drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The implementations described in the following embodiments do not represent all implementations consistent with the present application. They are only examples of systems and methods consistent with some aspects of the present application as detailed in the claims.

[0071] It should be noted that the brief description of terms in this application is only for the convenience of understanding the embodiments described below, and is not intended to limit the embodiments of this application. Unless otherwise specified, these terms should be understood according to their common and usual meanings.

[0072] The terms "first", "second", "third", etc. in the specification and claims of this application and the above drawings are used to distinguish similar or similar objects or entities, and do not necessarily mean to limit a specific order or sequence, unless otherwise noted. It should be understood that the terms used in this way can be interchangeable under appropriate circumstances.

[0073] The terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover but not exclude inclusion, for example, a product or device comprising a list of components is not necessarily limited to all the components expressly listed but may include other components not expressly listed or inherent to such product or device.

[0074] The term "module" refers to any known or later developed hardware, software, firmware, artificial intelligence, fuzzy logic, or combination of hardware and / or software code that is capable of performing the functions associated with that element.

[0075] The embodiments of the present application can be applied to various types of projection devices. A projection device is a projection device that can project an image or video onto a screen. The projection device can project a laser beam of a specific color onto a screen through the refraction of an optical component to form a specific image. During the projection process, a certain distance can be maintained between the projection device and the screen so that the image formed on the screen can conform to the focal length range of the optical component to obtain a clear image. The following will take a projector as an example to describe the projection device and the projection control method.

[0076] Projectors can be connected to computers, broadcasting networks, the Internet, VCD (Video CompactDisc), DVD (Digital Versatile Disc Recordable), game consoles, DV, etc. through different interfaces to play corresponding video signals. Projectors are widely used in homes, offices, schools, and entertainment venues.

[0077] Figure 1Schematic diagrams of projection scenes of projection devices in some embodiments are shown. Figure 1 As shown, the projection scene provided by the present application includes a projection screen 1 and a projection device 2. The projection screen 1 is fixed at a first position of the projection surface. For example, a wall can be used as the projection surface, and a curtain can be used as the projection screen and fixed at the first position of the projection surface. The projection device 2 is placed at a second position so that the image projected by it matches the projection screen 1.

[0078] Figure 2 Schematic diagram of the optical path of the projection device in some embodiments is shown. Figure 2 As shown, the projection device 2 includes a light source 100, an optical machine 200 and a lens 300. The light source 100 provides illumination for the optical machine 200, and the optical machine 200 modulates the light beam of the light source and outputs it to the lens 300 for imaging, and projects it onto the projection surface 400 to form a projection screen. Since the light source 100, the optical machine 200, and the lens 300 are used together to emit projection light to project the projection screen, in some embodiments of the present application, the light source 100, the optical machine 200, and the lens 300 are collectively referred to as a light output component.

[0079] In some embodiments, the light source 100 of the projection device 2 includes a light emitter component 110 and an optical lens component 120 . The light beam emitted by the light emitter component 110 can pass through the optical lens component 120 to provide lighting for the optical engine 200 .

[0080] It should be noted that in the embodiment of the present application, the light source 100 may be a laser light source, an LED light source, or a Liquid Crystal Display, i.e., a liquid crystal display LCD light source, and the present application does not specifically limit this. For example, taking the light source 100 as a laser light source as an example, when the light source 100 is a laser light source, in some embodiments, the optical machine 200 of the projection device 2 may be implemented to include a blue optical machine, a green optical machine, a red optical machine, and may also include a heat dissipation system, a circuit control system, etc.

[0081] Figure 3 FIG. 1 is a schematic diagram showing a circuit structure of a projection device provided by some embodiments. Figure 3 As shown, the projection device 2 may include a display control circuit 10, a light source 100, at least one light driving component 30 and at least one brightness sensor 40. Taking the light source 100 as a laser light source as an example, when the light source 100 is a laser light source, the light source 100 may include at least one laser corresponding to the at least one light driving component 30.

[0082] Based on the circuit architecture, the projection device 2 can achieve adaptive adjustment. For example, by setting a brightness sensor 40 in the light output path of the light source 100 , the brightness sensor 40 can detect the first brightness value of the laser light source and send the first brightness value to the display control circuit 10 .

[0083] The display control circuit 10 can obtain the second brightness value corresponding to the driving current of each laser, and when it is determined that the difference between the second brightness value of the laser and the first brightness value of the laser is greater than the difference threshold, it is determined that a COD fault occurs in the laser; the display control circuit can adjust the current control signal of the laser driving component corresponding to the laser until the difference is less than or equal to the difference threshold, thereby eliminating the COD fault of the blue laser; the projection device 2 can eliminate the COD fault of the laser in time, reduce the damage rate of the laser, and improve the image display effect of the projection device 2.

[0084] Figure 4 FIG. 1 shows a schematic diagram of the structure of a projection device provided in some embodiments. Figure 4 As shown, taking the light source 100 in the projection device 2 as a laser light source as an example, the laser light source may include independently arranged blue laser 101, red laser 102 and green laser 103, and the projection device 2 may also be called a three-color projection device, and the blue laser 101, the red laser 102 and the green laser 103 are all module lightweight (Mirai Console Loader, MCL) packaged lasers, which are small in size and are conducive to the compact arrangement of the optical path. It can be understood that the above only takes the light source 100 as a laser light source as an example for exemplary description, and does not limit the light source 100 to a laser light source, but may also be an LED light source, an LCD light source and other forms of light sources.

[0085] In some embodiments, the controller includes at least one of a central processing unit (CPU), a video processor, an audio processor, a graphics processing unit (GPU), a RAM Random Access Memory (RAM), a ROM (Read-Only Memory, ROM), a first interface to an nth interface for input / output, a communication bus (Bus), etc.

[0086] In some embodiments, after the projection device 2 is started, it can directly enter the display interface of the last selected signal source, or the signal source selection interface, where the signal source can be a preset video on demand program, or at least one of an HDMI interface, a live TV interface, etc. After the user selects a different signal source, the projector can display the content obtained from different signal sources.

[0087] In some embodiments, the projection device 2 may be configured with an image acquisition device 700 such as a camera, which is used to work in conjunction with the projection device 2 to achieve adjustment and control of the projection process. For example, the camera configured by the projection device 2 may be specifically implemented as a 3D camera or a binocular camera; when the camera is implemented as a binocular camera, it specifically includes a left camera and a right camera; the binocular camera may obtain the projection medium corresponding to the projection device 2, such as a screen, that is, the image and playback content presented by the projection surface 400, and the image or playback content is projected by the built-in optical machine 200 of the projection device 2.

[0088] The image acquisition device can be used to capture the image displayed on the projection surface 400, and can be a camera. The camera can include a lens assembly, in which a photosensitive element and a lens are provided. The lens refracts light through a plurality of lenses, so that the light of the image of the scene can be irradiated on the photosensitive element.

[0089] Figure 5 Schematic diagram of the lens structure of the projection device provided in some embodiments is shown. In order to support the automatic focusing process of the projection device 2, such as Figure 5 As shown, the lens 300 of the projection device 2 may further include an optical component 310 and a drive motor 320. The optical component 310 is a lens group composed of one or more lenses, which can refract the light emitted by the optical machine 200 so that the light emitted by the optical machine 200 can be transmitted to the projection surface 400 to form a transmission content image.

[0090] The optical assembly 310 may include a lens barrel and a plurality of lenses disposed in the lens barrel. Depending on whether the position of the lens can be moved, the lens in the optical assembly 310 may be divided into a movable lens 311 and a fixed lens 312. By changing the position of the movable lens 311 and adjusting the distance between the movable lens 311 and the fixed lens 312, the overall focal length of the optical assembly 310 may be changed. Therefore, the driving motor 320 may drive the movable lens 311 to move its position by connecting to the movable lens 311 in the optical assembly 310, thereby realizing an automatic focusing function.

[0091] It should be noted that the focusing process described in some embodiments of the present application refers to changing the position of the movable lens 311 by driving the motor 320, thereby adjusting the distance between the movable lens 311 and the fixed lens 312, that is, adjusting the image plane position. Therefore, the imaging principle of the lens combination in the optical component 310, the adjustment of the focal length is actually adjusting the image distance, but in terms of the overall structure of the optical component 310, adjusting the position of the movable lens 311 is equivalent to adjusting the overall focal length of the optical component 310.

[0092] When the distance between the projection device 2 and the projection surface 400 is different, the lens of the projection device 2 needs to adjust different focal lengths to project a clear image on the projection surface 400. During the projection process, the distance between the projection device 2 and the projection surface 400 will require different focal lengths depending on the placement of the user. Therefore, in order to adapt to different usage scenarios, the projection device 2 needs to adjust the focal length of the optical component 310.

[0093] Figure 6 The figure shows a schematic diagram of the distance sensor and image acquisition device of the projection device provided by some embodiments. Figure 6 As shown, the projection device 2 may also have a built-in or external image acquisition device 700, which may be a camera that can capture images of the screen content projected by the projection device 2 to obtain a screen content image. The projection device determines whether the current lens focal length is appropriate by performing a clarity detection on the projected content image, and adjusts the focal length when it is not appropriate. When automatically focusing based on the screen content image captured by the camera 700, the projection device may continuously adjust the lens position and take pictures, and find the focusing position by comparing the clarity of the front and rear position pictures, thereby adjusting the movable lens 311 in the optical component to a suitable position. For example, the controller 500 may first control the drive motor 320 to gradually move the focus starting position of the movable lens 311 to the focus end position, and continuously obtain the screen content image through the camera during this period. Then, by performing a clarity detection on multiple screen content images, the position with the highest clarity is determined, and finally the drive motor 320 is controlled to adjust the movable lens 311 from the focus terminal to the position with the highest clarity to complete the automatic focusing.

[0094] The distance sensor 600 can be a sensor device based on the Time of Flight (TOF) principle, such as a laser radar, an infrared radar, etc., which can detect the distance between the projection surface 400 and the optical machine 200. The distance sensor 600 can be set at the position of the optical machine 200, including a signal transmitter and a receiver. During the interval distance detection process, the transmitter of the distance sensor 600 can transmit a wireless signal in the direction of the projection surface. After the wireless signal contacts the projection surface, it will be reflected back to the receiving end of the distance sensor 600, so that the signal flight time is calculated according to the time when the transmitter sends the signal and the time when the receiver receives the signal, and the actual flight distance of the wireless signal can be obtained in combination with the flight speed.

[0095] Figure 7 A schematic diagram of a system framework for implementing display control of a projection device provided in some embodiments is shown. Figure 7As shown, the projection device 2 has the characteristics of a telephoto micro-projector, and the controller can control the display of the projection light image through a preset algorithm to achieve functions such as automatic trapezoidal correction of the display screen, automatic screen entry, automatic obstacle avoidance, automatic focusing, and anti-eye-shooting.

[0096] In some embodiments, the projection device 2 is configured with a gyroscope sensor; when the device is moving, the gyroscope sensor can sense the position movement and actively collect movement data; then the collected data is sent to the application service layer through the system framework layer to support the application data required during the user interface interaction and application interaction process. The collected data can also be used for data calls by the controller in the algorithm service implementation.

[0097] In some embodiments, the projection device 2 is configured with a time-of-flight sensor. After the time-of-flight sensor collects corresponding data, the data will be sent to the corresponding time-of-flight service of the service layer; after the above-mentioned time-of-flight service obtains the data, it will send the collected data to the application service layer through the process communication framework, and the data will be used for interactive use such as controller data calls, user interfaces, and program applications.

[0098] In some embodiments, the image acquisition device 700 configured for the projection device 2 can be a binocular camera, a depth camera or a 3D camera, etc.; the image acquisition device 700 collects data and sends it to the camera service, and then the camera service sends the collected image data to the process communication framework and / or the projection device correction service; the projection device correction service can receive the camera acquisition data sent by the camera service, and the controller can call the corresponding control algorithm in the algorithm library according to the different functions to be implemented.

[0099] In some embodiments, data is interacted with the application service through the process communication framework, and then the calculation results are fed back to the correction service through the process communication framework; the correction service sends the obtained calculation results to the operating system of the projection device 2 to generate control signals, and sends the control signals to the optical machine 200 control drive to control the working condition of the optical machine 200 and realize automatic correction of the displayed image.

[0100] In some embodiments, when an image correction instruction is detected, the projection device 2 can correct the projected image. For the correction of the projected image, an association relationship between the distance, the horizontal angle, and the offset angle can be created in advance. Then the controller in the projection device 2 obtains the current distance from the optical machine 200 to the projection surface 400, and determines the angle between the optical machine 200 and the projection surface 400 at this moment in combination with the associated relationship, thereby realizing the projection image correction. Among them, the angle is specifically implemented as the angle between the central axis of the optical machine 200 and the projection surface 400.

[0101] In some embodiments, the projection device 2 automatically completes the calibration and refocuses, and the controller will detect whether the automatic focus function is turned on; when the automatic focus function is not turned on, the controller will end the automatic focus service; when the automatic focus function is turned on, the projection device 2 will obtain the detection distance of the time-of-flight sensor through the middleware for calculation.

[0102] The controller queries the preset mapping table according to the acquired distance to obtain the focal length of the projection device 2; then the middleware sets the acquired focal length to the optical machine 200 of the projection device 2; wherein the middleware is a series of applications for the focus control process. After the optical machine 200 emits laser light at the above focal length, the camera will execute the photo command; the controller determines whether the focus process of the projection device 2 is completed according to the acquired captured image and the evaluation function.

[0103] If the judgment result meets the preset completion conditions, the control of the automatic focusing process ends; if the judgment result does not meet the preset completion conditions, the middleware will fine-tune the focal length parameters of the optical machine 200 in the projection device 2, for example, the focal length can be gradually fine-tuned with a preset step length, and the adjusted focal length parameters will be set to the optical machine 200 again; thereby achieving repeated photo taking and clarity evaluation steps, and finally finding the optimal focal length through clarity comparison to complete automatic focusing.

[0104] In some embodiments, the projection device 2 can project the screen content onto the projection surface for the user to view the screen content. For example, the user can pre-set the screen content, such as a media image, and the user can control the projection device 2 to project the media image. The projection device 2 can project the media image onto the projection surface, and the projection surface can be a curtain or a wall in front of the projection device 2.

[0105] When there is an obstacle between the projection device 2 and the projection surface, the content projected by the projection device 2 may be blocked by the obstruction, resulting in the inability to display a complete image on the projection surface, seriously affecting the user's viewing experience. Therefore, in order to ensure that the complete image can be displayed on the projection surface, it is necessary to ensure that there is no obstruction between the projection device 2 and the projection surface.

[0106] The obstruction may be a fixed object. For example, if the user places the projection device 2 on the desktop, other objects placed on the desktop by the user or objects between the desktop and the projection surface may block the light source of the projection device 2, and the user needs to move these objects away. The obstruction may also be a user. For example, during the projection process, a user may pass through the area between the projection device 2 and the projection surface, thereby entering the light source emission area of ​​the projection device 2, thereby blocking the image projected by the projection device 2.

[0107] It should be noted that when a user enters the light source emission area of ​​the projection device 2, the projection light source of the projection device 2 may directly shine into the user's eyes, and the high-power projection light source may cause damage to the user's eyes. For this reason, the projection device 2 may be provided with an anti-eye function to protect the user's eyes.

[0108] During the projection process, the projection device 2 can perform human body detection in the projection area. The projection device 2 can take photos of the projection area through a camera, and perform human target detection based on the image data collected by the camera, so as to determine whether there is a human target intruding into the light source emitting area between the projection surface and the projection device 2. When there is a human target intruding, the projection device 2 can turn on the anti-radiation eye function, and when there is no human target intruding, the projection device 2 can turn off the anti-radiation eye function. Among them, the anti-radiation eye function can shut down the operation of the light source of the light emitting component. Until it is detected that there is no human body in the light source emitting area, the projection device 2 can turn off the anti-radiation eye function, thereby protecting users in the light source emitting area.

[0109] It should be noted that in some special scenarios such as screen projection, the projection device can receive the projection image sent by other devices and project it into the projection area. However, the projection image sent by other devices may not be completely valid image content, and there may be invalid content outside the image content, such as black border areas.

[0110] Therefore, in the picture that the projection device needs to project, the sizes of the effective image content and the light source emission area may be different, that is, only a part of the light source emission area on the projection surface may display the effective image content. Figure 8 Schematic diagrams showing effective content areas in some embodiments are shown. Figure 8 As shown, in the light source emission area of ​​the projection surface, only part of the area displays the image content. In the embodiment of the present application, this part of the area is called the effective content area, and the other area that does not display the effective content is called the invalid content area. There is no image content displayed in the invalid content area. Among them, Y is the effective content area, and W1 and W2 are the invalid content areas.

[0111] When a user enters the invalid content area in the light emission area but does not enter the valid content area, the projection light source will not cause damage to the user's eyes, but the projection device will still trigger the anti-eye function, and the projection device will turn off the light source, causing the projection process to be interrupted. Users who are not in the light emission area may be watching the screen content, and triggering the anti-eye function will interrupt the viewing process of these users, affecting the user's viewing experience.

[0112] To this end, the projection device provided in some embodiments of the present application can adaptively protect users in the light source emission area according to the content of the projected picture. During the projection process, the projection device can detect the content of the projected picture to determine the valid content area and the invalid content area in the picture content. When the picture content includes a valid content area and an invalid content area, the projection device can convert the coordinates of the valid content area to spatial coordinates, and detect the intersection of the human body area and the valid content area under the spatial coordinates. Based on the detection of the intersection of the human body area and the valid content area under the spatial coordinates, the anti-eye-shooting process is executed. Based on the detection of the absence of an intersection between the human body area and the valid content area under the spatial coordinates, the anti-eye-shooting process is not executed. This ensures that the projection device will not interrupt the projection process when the user does not enter the valid content area, so as to improve the user's viewing experience.

[0113] Fig. 9 A flowchart of the interaction of various components of the projection device in some embodiments is shown, including the following steps:

[0114] S901. When it is detected through a first image detection algorithm that the picture content includes a valid content area and an invalid content area, the coordinates of the valid content area are converted into spatial coordinates; wherein the grayscale values ​​or pixel values ​​of consecutive rows and / or consecutive columns of pixels in the invalid content area are the same, and the grayscale values ​​or pixel values ​​of the pixels are lower than a first threshold.

[0115] S902, if it is detected based on the first human body detection algorithm that there is an intersection between the human body area in the target image and the valid content area under the spatial coordinates, then an anti-eye-shooting process is executed;

[0116] If it is detected based on the first human body detection algorithm that there is no intersection between the human body area in the target image and the valid content area under the spatial coordinates, the anti-eye-shooting process is not executed.

[0117] In some embodiments, the user may input a projection instruction to the projection device 2 to instruct the projection device 2 to project the image content set by the user. In the embodiments of the present application, the content that the user specifies the projection device to project is referred to as the screen content.

[0118] In response to the projection instruction, the controller of the projection device 2 can control the light emitting component to project the picture content to the projection area in the projection surface 400. In the embodiment of the present application, the area where the picture content is displayed in the projection surface 400 is called the projection area, and the projection area is the light source emission area projected by the projection device 2 into the projection surface 400.

[0119] In some embodiments, the projection area may be a pre-set area, for example, a certain area on a wall or a screen placed in advance by the user, and the complete picture content may be displayed in the projection area for the user to watch.

[0120] The user can manually adjust the position and projection angle of the projection device 2 so that the picture content is completely in the projection area, but this manual adjustment method is cumbersome and has poor accuracy. To this end, the projection device 2 provided in the embodiment of the present application can be provided with an automatic screen entry function. The automatic screen entry function means that the projection device 2 can automatically determine the projection area in the projection surface 400 and project the picture content into the projection area, thereby avoiding the user manually adjusting the angle and position of the projection device 2 to improve the user experience.

[0121] When executing automatic screen entry, the controller can first construct a transformation matrix between the world coordinate system and the optical machine coordinate system based on the binocular camera. The transformation matrix can represent the homography relationship between the picture content in the projection surface 400 and the playback image card played by the optical machine. The homography relationship can be used to realize any projection transformation between the picture content and the playback image card.

[0122] The controller can first control the light emitting component to project the first picture card onto the projection surface 400. The first picture card can contain a number of feature points, so the first image captured by the camera will also contain all the feature points in the first picture card, and the position information of the projection surface 400 can be determined through the feature points. It should be noted that for a plane, when the positions of three points in the plane are determined, the position information of the plane can be determined. Therefore, in order to determine the position information of the projection surface 400, it is necessary to determine the positions of at least three points in the projection surface 400, that is, the first picture card needs to include at least three feature points.

[0123] In some embodiments, the first picture card may include patterns and color features preset by the user. Fig.10 Schematic diagrams of checkerboard graphics cards in some embodiments are shown. Fig.10 As shown, the first image card may be a checkerboard image card, the checkerboard image card is set as a black and white checkerboard, and the feature points included in the checkerboard image card are the corner points of a rectangle. Fig.11 Schematic diagrams of donut chart cards in some embodiments are shown. Fig.11 As shown, the first picture card can also be set as a donut picture card, and the characteristic points contained in the donut picture card are corresponding solid points on each circle. In some embodiments, the first picture card can also be set as a combination of the above two types of patterns, or set as other patterns with identifiable characteristic points.

[0124] Fig.12 A schematic diagram of a process for obtaining a mapping relationship in some embodiments is shown.

[0125] In some embodiments, the controller can control the camera to shoot the first image card displayed on the projection surface 400 to obtain a first image, and obtain the position of the feature point in the first image. The camera can be a binocular camera, through which the first image card is shot, the left camera shoots to obtain one image, and the right camera shoots to obtain another image.

[0126] The controller can perform image recognition processing on the two images to obtain the first coordinates of the feature points in the images. The first coordinates refer to the coordinate information of the feature points in the image coordinate system corresponding to the first image.

[0127] For the same feature point, its position in the image captured by the left camera and its position in the image captured by the right camera may be different. The coordinates of the feature point in the camera coordinate system of either the left or right camera can be determined by the two positions of the same feature point in the two images. In the embodiment of the present application, the second coordinate is used to represent the coordinate information of the feature point in the camera coordinate system.

[0128] According to the position information of the same feature point in the two images captured by the left and right cameras, the controller can obtain the second coordinate of the feature point in the camera coordinate system of either camera. The controller can convert the second coordinate into a third coordinate. In the embodiment of the present application, the third coordinate refers to the coordinate information of the feature point in the optical-mechanical coordinate system.

[0129] It should be noted that the optomechanical coordinate system and the camera coordinate system can be converted to each other, so the coordinates of the feature point in the camera coordinate system can be converted to the coordinates in the optomechanical coordinate system. According to the external parameters between the optomechanical camera and the camera, the conversion relationship between the optomechanical coordinate system and the camera coordinate system can be determined, and the third coordinate of the feature point in the optomechanical coordinate system can be obtained.

[0130] The controller may obtain the projection surface 400 equation of the projection surface 400 in the optomechanical coordinate system according to the third coordinate of the feature point in the optomechanical coordinate system. The controller may obtain the third coordinates of at least three feature points in the first image in the optomechanical coordinate system, and fit the third coordinates to obtain the projection surface 400 equation of the projection surface 400 in the optomechanical coordinate system.

[0131] The controller can obtain the transformation matrix between the optomechanical coordinate system and the world coordinate system according to the projection surface 400 equation. The transformation matrix can represent the projection relationship between the optically projected chart and the projection surface 400, thereby realizing the transformation of the coordinates of a certain point between the world coordinate system and the optomechanical coordinate system.

[0132] For the projection area that has been determined in the projection surface 400, its coordinate representation in the world coordinate system can be determined, and the controller can obtain the position information of the projection area in the optical-mechanical coordinate system according to the transformation matrix, thereby projecting the image to the projection area.

[0133] In some embodiments, the controller can control the light emitting component to project the picture content to the projection area in the projection surface 400. Considering some special cases, such as in the projection mode, the picture content may not be completely valid image content, and there may be invalid content such as black edges.

[0134] To this end, the controller can detect the valid content area and the invalid content area in the screen content. It should be noted that the entire area of ​​the image projected by the projection device may be valid image content (also called valid content), or only part of the area may display valid content. In the embodiment of the present application, the area that displays valid image content is called the valid content area, and the area that does not display valid content is called the invalid content area.

[0135] In some embodiments, the controller can detect the valid content area and the invalid content area in the picture content through the first image detection algorithm. Among them, the invalid content area can be a black border area, and the pixels in the invalid content area can all be black pixels. Therefore, the first image detection algorithm can adopt a black border detection algorithm.

[0136] Each pixel in the black border area is black, so the grayscale value and pixel value of the pixel are both values ​​corresponding to black. To this end, the controller can detect the grayscale value or pixel value of the pixel in the picture content, and the pixel value refers to the color value of the pixel, such as the RGB value.

[0137] When black edge detection is performed on the screen content, each row of pixels and each column of pixels in the screen content may be detected to determine whether each row or each column is in a black edge state.

[0138] For the content of the picture, there may be black edges in the vertical direction on the left and right sides, there may be black edges in the horizontal direction on the top and bottom sides, or both. Therefore, the pixel points of each row and each column can be detected to ensure that the black edge area is completely detected.

[0139] The controller can detect a row of pixels and a column of pixels in the screen content to determine whether each pixel in a row or a column is black. It should be noted that there may be a certain error in the color of the pixels in the screen content, and a ratio threshold value, such as 95%, can be pre-set. If the colors of the pixels in a row or a column that exceed the ratio threshold value are all black, then all the pixels in the row or the column are considered to be black.

[0140] It should be noted that in the valid content, there may be a row or a column of pixels that are all black, so if there is only one row or column of pixels that is black, it cannot be determined as a black border. A quantity threshold can be pre-set, which is called the first quantity in the embodiment of the present application. If the pixels of rows or columns exceeding the first quantity are black, and these rows or columns are arranged continuously in position, these continuously arranged rows or columns are considered to be black border areas.

[0141] Considering that the black edge of the image source may not be a pure black area when generating the screen content, there may be some deviation. A threshold value may be set in advance, which is called the first threshold value in the embodiment of the present application. When the gray value or pixel value of the pixel point is lower than the first threshold value, it is considered to be a black pixel point. For example, the black pixel value is (0,0,0), and the first threshold value corresponding to the pixel value may be set to (10,10,10). Pixel points with pixel values ​​less than the first threshold value can be considered to be black pixels.

[0142] Therefore, based on detecting that the grayscale values ​​or pixel values ​​of at least a first number of consecutive rows and / or at least a first number of consecutive columns of pixels are the same, and the grayscale values ​​or pixel values ​​of the pixels are lower than a first threshold, the controller can mark the above-mentioned at least a first number of consecutive rows and / or at least a first number of consecutive columns of pixels as invalid content areas.

[0143] The controller may mark an area other than the invalid content area in the screen content as a valid content area.

[0144] It should be noted that the screen content may include both valid content areas and invalid content areas, or may include only valid content areas without any invalid content areas.

[0145] If no region meeting the above conditions is detected in the screen content, the controller may mark that the screen content does not include an invalid content region.

[0146] In some embodiments, the valid content area and the invalid content area may also be detected by contour detection or other methods. The controller may first detect a closed contour area in the picture content.

[0147] The controller can perform contour detection processing on the image content to obtain at least one closed contour area. The controller can use a preset contour detection algorithm, such as a Sobel algorithm, a Canny edge detection algorithm, etc. Through the contour detection algorithm, various closed contours in the image can be obtained, which are referred to as closed contour areas in the embodiment of the present application. Among them, contour detection can calculate the gray value of each pixel in the image, and determine the extreme point of the gray value change, and the pixel point corresponding to the extreme point is the pixel point of the closed contour. After counting all extreme points, the pixel points corresponding to the extreme points with the same gray value can be determined as a closed contour.

[0148] The grayscale values ​​of all pixels in the invalid content area are the same, and the pixel values ​​of all pixels are also the same, which are all values ​​corresponding to black. Whether the pixel is black can be detected by the grayscale value or pixel value of the pixel. A threshold value can be pre-set, which is called the second threshold value in the embodiment of the present application, and is used to characterize whether the pixel is invalid content. The second threshold value can include a second grayscale value threshold value and a second pixel value threshold value.

[0149] The controller can detect the grayscale value of the pixel. If the grayscale values ​​of all pixels in a closed contour area are the same and the grayscale values ​​of all pixels are lower than the second grayscale value threshold, it means that all pixels in the closed contour area are black pixels, so the controller can mark the closed contour area as an invalid content area.

[0150] The controller may also detect the pixel values ​​of the pixels. If the pixel values ​​of all pixels in a closed contour area are the same and the pixel values ​​of all pixels are lower than the second pixel value threshold, it means that all pixels in the closed contour area are black pixels, so the controller may mark the closed contour area as an invalid content area.

[0151] The effective content area displays image content, which can be a pure color picture or an image with various screens.

[0152] For valid content with a picture, the grayscale values ​​or pixel values ​​of all pixels are not exactly the same, but there will be differences. For a pure color picture, the grayscale values ​​of all pixels are the same, and the pixel values ​​of all pixels are also the same. It should be noted that when the projection device projects a pure black picture, it will not harm the user, so there is no need to perform the anti-eye function. Therefore, for a pure black picture, it can be determined as invalid content.

[0153] For valid content with a picture, it may contain black pixels or may not contain black pixels, but it must contain pixels of colors other than black. For a pure color picture of colors other than black, all pixels are not black pixels. Therefore, when a certain number of pixels of colors other than black exist in a closed contour area, it indicates that the closed contour area contains valid content. In the embodiment of the present application, the certain number is referred to as the second number.

[0154] The controller can detect the grayscale value of the pixel points. If the grayscale values ​​of more than a second number of pixel points in a closed contour area are higher than a second grayscale value threshold, it means that there is valid content in the closed contour area, so the controller can mark the closed contour area as a valid content area.

[0155] Alternatively, the controller may detect the pixel values ​​of the pixels. If the pixel values ​​of more than a second number of pixels in a closed contour area are higher than a second pixel value threshold, it indicates that there is valid content in the closed contour area, so the controller may mark the closed contour area as a valid content area.

[0156] It should be noted that the size of each closed contour area may be different, that is, the number of pixels in the closed contour area may be different. To this end, different first quantities may be set for different closed contour areas. For example, a ratio may be pre-set, and the controller may detect the number of pixels in the closed contour area, and use the product of the number of pixels and the preset ratio as the second number.

[0157] In some embodiments, after detecting through the first image detection algorithm that the picture content includes a valid content area and an invalid content area, the controller can control the light-emitting component to project the picture content into the projection area of ​​the projection surface to perform anti-eye detection.

[0158] After the controller detects the effective content area, it can obtain the location information of the effective content area, such as the coordinates. The controller can detect whether the user enters the effective content area to determine whether the anti-glare function needs to be turned on.

[0159] The controller can collect image data of the projection surface 400 through the image acquisition device, and the controller can control the image acquisition device to collect image data of the projection surface 400 according to the first acquisition cycle. The image acquisition device can collect image data in real time after the projection device 2 is turned on. In the embodiment of the present application, the image collected by the image acquisition device is referred to as the target image. The image acquisition device can be a camera, and the image data captured by the camera can be RGB image data, but it is not limited to data in other formats such as YUV, nor is it limited to the size of the resolution.

[0160] It should be noted that the coordinates of the effective content area are the coordinates in the coordinate system corresponding to the light output component, that is, the coordinates in the optical machine coordinate system. The controller can convert the coordinates of the effective content area into spatial coordinates, which are the coordinate system corresponding to the image acquisition device, which is called the first coordinate system in the embodiment of the application, that is, the coordinates in the camera coordinate system.

[0161] From the description of the above transformation matrix, it can be known that the optical-mechanical coordinate system and the camera coordinate system can be converted to each other. Therefore, the controller can convert the coordinates of the effective content area in the optical-mechanical coordinate system into the spatial coordinates in the first coordinate system, which is also referred to as the first spatial coordinates in the embodiment of the present application.

[0162] In some embodiments, the controller may execute a first human body detection algorithm to detect a human body region in a target image, and detect the intersection of the human body region and the valid content region. The first human body detection algorithm may be a human body contour detection algorithm. In the embodiments of the present application, the technical solution of the present application is described by taking a human body target as an example. It should be understood that the technical solution provided in the embodiments of the present application is not limited to a human body target, and other targets may also be detected according to actual needs.

[0163] When detecting the human body region in the target image, the controller may first perform image binarization processing on the target image to obtain a binary image. Image binarization is to set the grayscale value of the pixel points of the image to 0 or 255, so that the entire image presents an obvious black and white effect.

[0164] A grayscale value threshold may be pre-set in the projection device 2. The controller may detect each pixel in the target image, and if the grayscale value of the pixel is higher than the grayscale value threshold, the grayscale value of the pixel is updated to 255. If the grayscale value of the pixel is not higher than the grayscale value threshold, the grayscale value of the pixel is updated to 0.

[0165] The controller can detect the human body area in the binary image. The controller can perform human body contour detection processing on the binary image, for example, the binary image can be processed using the Canny edge detection algorithm to detect the human body contour in the binary image. When performing contour detection, the position information of the contour can also be obtained.

[0166] Based on detecting that no human body region exists in the binary image, it indicates that no user exists in the target image, and the controller may mark that no intersection exists between the human body region in the target image and the valid content region under the first spatial coordinate.

[0167] Based on detecting the presence of a human body region in the binary image, the controller can obtain position information of the human body region, which is referred to as first position information in the embodiment of the present application. The controller can detect the intersection of the human body region in the target image and the valid content region at the first spatial coordinates based on the first position information of the human body region and the first spatial coordinates of the valid content region.

[0168] The first position information of the human body region is the coordinate of the human body region, so the controller can detect whether the first spatial coordinate and the first position information have the same coordinate. If the same coordinate exists, it means that the human body region in the target image and the valid content region under the first spatial coordinate have an intersection. If the same coordinate does not exist, it means that there is no intersection.

[0169] In some embodiments, the first human detection algorithm may adopt a human recognition algorithm. The controller may extract image features of the target image and analyze them to determine whether there is a human body in the image. The controller may input the target image into a pre-built mask model to detect the target. The mask model is an encoder and decoder that recognizes the target contour based on pixels. The encoder and decoder refer to an image processing process, that is, the original image is encoded into a vector array with abstract features by the encoder, and then the vector array is decoded into another form of image by the decoder.

[0170] Based on the mask model, the target outline in the target image can be identified, so as to obtain the mask image output by the mask model. Among them, the mask image includes a first pixel value and a second pixel value, the first pixel value is used to characterize the target, and the second pixel value is used to characterize the non-target. The area of ​​the first pixel value is extracted in the mask image to obtain the target mask. For example. The mask image can be a grayscale image marking a human target, and the image matrix of the grayscale image includes two types of data 0 / 1 or 0 / 255, 0 represents a non-human target (background), 1 or 255 represents a human target, and the area of ​​data 1 or 255 is the target mask. The target mask can be identified and segmented by the encoder and decoder, so as to determine the human area.

[0171] For each pixel of the image, it can be determined whether it is a human target, so that when non-human target interference objects such as chairs and clothes enter the projection area, they will not be protected. Only when human targets enter the projection area can they be protected, and part of the human target's body (such as fingers, half of the face, etc.) can also be detected when entering the projection area, thereby protecting the user. It should be noted that the encoder and decoder described in the embodiments of the present application can also be implemented using image feature extraction calculation methods, such as SIFT (scale-invariant feature transform) and HOG (histogram of oriented gradients). It can also be implemented using matrix operations of SVM (support vector machine). It can also be implemented by the calculation method of convolutional neural network or Transformer. This application does not make specific restrictions on this.

[0172] In some embodiments, if the first human body detection algorithm detects that there is an intersection between the human body area in the target image and the valid content area under the spatial coordinates, the controller can execute an anti-eye-shooting process.

[0173] If it is detected based on the first human body detection algorithm that there is no intersection between the human body area in the target image and the valid content area under the spatial coordinates, the controller does not execute the anti-eye-shooting process.

[0174] It should be noted that the intersection between the human body region and the valid content region includes two situations: the human body region is in the valid content region but not in the invalid content region, and the human body region is in both the valid content region and the invalid content region.

[0175] Fig.13 Schematic diagrams of human body areas and projection areas in some embodiments are shown. Fig.13 As shown, a part of the human body region T is in the valid content region, and the other part is in the invalid content region.

[0176] Fig.14 Schematic diagrams of human body areas and projection areas in some embodiments are shown. Fig.14 As shown, the entire human body region T is within the effective content region.

[0177] For both of the above situations, the controller executes the anti-eye process.

[0178] If there is no intersection between the human body region and the valid content region, and there is an intersection between the human body region and the invalid content region, it means that the user enters the invalid content region but does not enter the valid content region. Fig.15 Schematic diagrams of human body areas and projection areas in some embodiments are shown. Fig.15 As shown, the human body area T is entirely in the invalid content area, and there is no part in the valid content area. At this time, the controller does not execute the anti-eye-shooting process.

[0179] In some embodiments, the projection device 2 may also detect the human body area through a distance sensor. During the projection process of the projection device 2, the controller may control the distance sensor to collect distance image data of the projection surface 400 according to the second collection period. The distance sensor may collect distance image data in real time after the projection device 2 is turned on. The first collection period and the second collection period may be the same or different.

[0180] The controller can obtain the distance image collected by the distance sensor, and detect the intersection of the human body area and the effective content area according to the distance image.

[0181] The coordinates of the effective content area are the coordinates in the coordinate system corresponding to the light emitting component, that is, the coordinates in the optical machine coordinate system. The controller can convert the coordinates of the effective content area into spatial coordinates, which are referred to as second spatial coordinates in the embodiment of the present application. The second spatial coordinates refer to the coordinates in the second coordinate system corresponding to the distance sensor.

[0182] The controller may detect the intersection of the human body area in the distance image and the effective content area under the second space coordinates through a second image detection algorithm. The second image detection algorithm may include the following steps:

[0183] The controller may first obtain an initial distance image, wherein the initial distance image is a distance image collected by the distance sensor after the projection device 2 is turned on. That is, after the projection device 2 is turned on, the distance sensor will be controlled to collect an initial image.

[0184] The controller can perform background frame difference processing on the distance image currently collected by the distance sensor and the initial distance image to obtain a foreground image. It should be noted that when there is no user, the space between the projection surface 400 and the projection device 2 will not change, that is, the distance image collected by the distance sensor at this time is the same as the initial distance image. When there is a user, the user will be in the space between the projection surface 400 and the projection device 2, resulting in the distance image collected by the distance sensor at this time being different from the initial distance image.

[0185] In the embodiment of the present application, the initial distance image is used as the background image. If the user enters between the projection surface 400 and the projection device 2, the user is equivalent to the foreground content in front of the background image. The controller can obtain the foreground image in front of the background image by performing background frame difference processing on the currently collected distance image and the initial distance image. By detecting whether there is a user in the foreground image, it can be determined whether the user enters the space between the projection surface 400 and the projection device 2.

[0186] The controller can detect the human body contour in the foreground image, where the foreground image is a distance image after background frame difference processing, and the detection value corresponding to each pixel in the distance image is recorded. When the detection value is greater than 0, the pixel can be considered to be the user's body.

[0187] Based on the detection that there is no human body area in the foreground image, it means that there is no user in the distance image, and the controller can mark that there is no intersection between the human body area in the distance image and the valid content area under the second space coordinate.

[0188] Based on detecting the existence of a human body area in the foreground image, the controller can obtain position information of the human body area, which is referred to as second position information in the embodiment of the present application. The controller can detect the intersection of the human body area in the distance image and the effective content area under the second space coordinates based on the second position information.

[0189] The second position information is the coordinates of the human body area in the distance image, so the controller can detect whether the second spatial coordinates and the second position information have the same coordinates. If the same coordinates exist, it means that the human body area in the distance image and the valid content area under the second spatial coordinates have an intersection. If the same coordinates do not exist, it means that there is no intersection.

[0190] In some embodiments, based on detecting the intersection of a human body area in a target image and a valid content area under a first spatial coordinate, and / or the intersection of a human body area in a distance image and a valid content area under a second spatial coordinate, the controller executes an anti-eye-shooting process.

[0191] Based on detecting that there is no intersection between the human body area in the target image and the valid content area under the first spatial coordinate, and there is no intersection between the human body area in the distance image and the valid content area under the second spatial coordinate, the controller does not execute the anti-eye-shooting process.

[0192] In some embodiments, the distance sensor can also detect the distance between the projection device 2 and the object to be measured (e.g., the user) during the process of collecting the distance image. Considering the measurement accuracy of the distance sensor, the measurement result may be unreliable when the distance exceeds a certain distance. To this end, a distance threshold can be pre-set in the projection device 2.

[0193] The controller may first detect the intersection of the human body region in the target image and the valid content region under the first spatial coordinate. Based on detecting that there is no intersection between the human body region in the target image and the valid content region under the first spatial coordinate, the controller may detect the intersection of the human body region in the distance image and the valid content region under the second spatial coordinate.

[0194] Based on the detection that there is no intersection between the human body area in the distance image and the valid content area under the second space coordinates, the controller may not execute the anti-eye-shooting process.

[0195] Based on the detection of the intersection between the human body area in the distance image and the valid content area under the second space coordinate, the controller can obtain the interval distance. If the interval distance is less than or equal to the distance threshold, the controller can execute the anti-eye-shooting process; if the interval distance is greater than the distance threshold, the controller does not execute the anti-eye-shooting process.

[0196] In some embodiments, if the screen content is entirely valid content area and there is no invalid content area, the controller can detect whether the user enters the screen content and perform the anti-eye-shooting function after the user enters the screen content.

[0197] The controller can convert the coordinates of the screen content into space coordinates.

[0198] Based on the detection of the intersection between the human body area in the target image and the screen content under the spatial coordinates, the controller can execute the anti-eye-shooting process. Based on the detection of the non-intersection between the human body area in the target image and the screen content under the spatial coordinates, the controller does not execute the anti-eye-shooting process.

[0199] It should be noted that the solution for detecting whether there is an intersection between the human body area and the picture content under the spatial coordinates can refer to the steps of the aforementioned effective content area, which will not be repeated here.

[0200] In some embodiments, considering that the image acquisition device and the distance sensor have different frequencies of acquiring images, it can be set that each time the image acquisition device or the distance sensor acquires an image, the above detection process is performed once to confirm whether the user has entered the valid content area. If one of the image acquisition device and the distance sensor acquires a new image, but the other device has not currently acquired a new image, the image acquired by the other device for the last time is used as the current image for detection.

[0201] In some embodiments, after the projection device is turned on, the controller can detect the projection mode of the projection device 2. If the projection mode of the projection device 2 is the screen projection mode, the controller can detect the grayscale value or pixel value of the pixel point in the picture content to detect the valid content area and the invalid content area of ​​the projection area.

[0202] The controller can detect whether the user enters the valid content area to determine whether to execute the anti-eye-shooting process.

[0203] If the projection mode of the projection device 2 is not the screen projection mode, the controller can detect whether the user enters the screen content to determine whether to execute the anti-eye-shooting process.

[0204] In some embodiments, the projection device 2 can be set to three modes: standard mode, follow-up protection mode, and screen-off protection mode. Among them, the user is not protected in the standard mode. In the follow-up protection mode, the user's eyes are protected by generating an occlusion image. The projection device 2 can set an occlusion image in the detected user area, and generate new screen content according to the occlusion image and the screen content, wherein the occlusion image is displayed on the upper layer of the screen content, and the projection device 2 projects the new screen content to the projection area. The brightness of the occlusion image is low, so the projected occlusion image is used to cover the user, thereby achieving the effect of protecting the user. In the screen-off protection mode, the projection device 2 can directly turn off the light source.

[0205] In the standard mode, the projection device 2 does not perform the eye protection function, so there is no need to perform the above user detection process.

[0206] In the follow-up protection mode and the screen-off protection mode, when the anti-eye-shooting function is executed, the controller can obtain the current mode of the projection device 2. If the projection device 2 is in the follow-up protection mode, the controller can obtain the user area according to the target image, thereby generating a shielding image to protect the user with the shielding image. If the projection device 2 is in the screen-off protection mode, the controller can control the light output component to stop projecting content to the projection surface 400 and turn off the light source.

[0207] The embodiment of the present application also provides a projection control method, which is applied to a projection device, and the method includes:

[0208] Step 901: When it is detected through a first image detection algorithm that the picture content includes a valid content area and an invalid content area, the coordinates of the valid content area are converted into spatial coordinates; wherein the grayscale values ​​or pixel values ​​of consecutive rows and / or consecutive columns of pixels in the invalid content area are the same, and the grayscale values ​​or pixel values ​​of the pixels are lower than a first threshold.

[0209] Step 902: If it is detected based on the first human body detection algorithm that there is an intersection between the human body area in the target image and the valid content area under the spatial coordinates, then an anti-eye-shooting process is executed;

[0210] If it is detected based on the first human body detection algorithm that there is no intersection between the human body area in the target image and the valid content area under the spatial coordinates, the anti-eye-shooting process is not executed.

[0211] The same and similar parts between the various embodiments in this specification can be referenced to each other and will not be described again here.

[0212] Those skilled in the art can clearly understand that the technology in the embodiments of the present invention can be implemented by means of software plus a necessary general hardware platform. Based on this understanding, the technical solution in the embodiments of the present invention is essentially or the part that contributes to the prior art can be embodied in the form of a software product, which can be stored in a storage medium such as ROM / RAM, a disk, an optical disk, etc., and includes a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods of various embodiments of the present invention or certain parts of the embodiments.

[0213] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

[0214] For ease of explanation, the above description has been made in conjunction with specific embodiments. However, the above exemplary discussion is not intended to be exhaustive or limit the embodiments to the specific forms disclosed above. Based on the above teachings, various modifications and variations can be obtained. The selection and description of the above embodiments are intended to better explain the principles and practical applications, so that those skilled in the art can better use the embodiments and various different variations of the embodiments suitable for specific use considerations.

Claims

1. A projection device, characterized in that: include: A light emitting component is configured to project image content onto a projection surface; An image acquisition device, configured to acquire a target image from the projection surface; The controller is configured as: In the case where it is detected by the first image detection algorithm that the picture content includes a valid content area and an invalid content area, the coordinates of the valid content area are converted into spatial coordinates; wherein the grayscale values ​​or pixel values ​​of consecutive rows and / or consecutive columns of pixels in the invalid content area are the same, and the grayscale values ​​or pixel values ​​of the pixels are lower than a first threshold; If it is detected based on the first human body detection algorithm that there is an intersection between the human body area in the target image and the valid content area under the spatial coordinates, then the anti-eye-shooting process is executed; If it is detected based on the first human body detection algorithm that there is no intersection between the human body area in the target image and the valid content area under the spatial coordinates, the anti-eye-shooting process is not executed.

2. The projection device according to claim 1, characterized in that: The controller is further configured to: before executing, when detecting through the first image detection algorithm that the screen content includes a valid content area and an invalid content area, converting the coordinates of the valid content area into space coordinates: Detecting the grayscale value or pixel value of a pixel point in the picture content; Based on detecting that the grayscale values ​​or pixel values ​​of at least a first number of consecutive rows and / or at least a first number of consecutive columns of pixels are the same, and the grayscale values ​​or pixel values ​​of the pixels are lower than a first threshold, marking the at least a first number of consecutive rows and / or at least a first number of consecutive columns of pixels as invalid content areas; An area other than the invalid content area in the screen content is marked as a valid content area.

3. The projection device according to claim 2, characterized in that: Based on detecting that the screen content does not include an invalid content area, the controller is further configured to: Converting the coordinates of the screen content into space coordinates; Based on detecting that there is an intersection between the human body area in the target image and the image content under the spatial coordinates, an anti-eye-shooting process is executed; Based on the fact that no intersection exists between the human body area in the target image and the picture content under the spatial coordinates, the anti-eye-shooting process is not executed.

4. The projection device according to claim 1, characterized in that: The spatial coordinates include first spatial coordinates in a first coordinate system corresponding to the image acquisition device; after the controller converts the coordinates of the effective content area into the spatial coordinates, the controller is further configured to: Performing image binarization processing on the target image to obtain a binary image; Detecting a human body region in the binary image; Based on detecting that no human body region exists in the binary image, marking that no intersection exists between the human body region in the target image and the valid content region under the first spatial coordinate; Based on detecting that a human body region exists in the binary image, obtaining first position information of the human body region; According to the first position information and the first spatial coordinates, an intersection of a human body region in the target image and a valid content region under the first spatial coordinates is detected.

5. The projection device according to claim 4, characterized in that: Also includes: A distance sensor is configured to collect a distance image of the projection surface; the spatial coordinates also include second spatial coordinates in a second coordinate system corresponding to the distance sensor; After the controller converts the coordinates of the effective content area into space coordinates, the controller is further configured to: Detecting the intersection of the human body area in the distance image and the effective content area under the second space coordinates; Based on detecting that there is an intersection between the human body area in the target image and the valid content area under the first spatial coordinate, and / or that there is an intersection between the human body area in the distance image and the valid content area under the second spatial coordinate, executing the anti-eye-shooting process; Based on detecting that there is no intersection between the human body area in the target image and the valid content area under the first spatial coordinate, and there is no intersection between the human body area in the distance image and the valid content area under the second spatial coordinate, the anti-eye-shooting process is not executed.

6. The projection device according to claim 4, characterized in that: Also includes: A distance sensor is configured to collect a distance image of the projection surface and detect a distance between the projection device and the user; The spatial coordinates also include second spatial coordinates in a second coordinate system corresponding to the distance sensor; Based on detecting that there is no intersection between the human body area in the target image and the valid content area under the first spatial coordinate, the controller is further configured to: Detecting the intersection of the human body area in the distance image and the effective content area under the second space coordinates; Based on detecting that there is no intersection between the human body area in the distance image and the valid content area under the second space coordinate, not executing the anti-eye-shooting process; Based on detecting that there is an intersection between the human body area in the distance image and the valid content area under the second space coordinates, acquiring the interval distance; If the interval distance is less than or equal to the distance threshold, the anti-eye-shooting process is executed; if the interval distance is greater than the distance threshold, the anti-eye-shooting process is not executed.

7. The projection device according to claim 5 or 6, characterized in that: The controller performs detection of the intersection of the human body area in the distance image and the valid content area under the second space coordinate, and is specifically configured as follows: Acquire an initial distance image; the initial distance image is a distance image collected by the distance sensor after the projection device is turned on; Performing background frame difference processing on the range image collected by the range sensor and the initial range image to obtain a foreground image; Detecting a human body region in the foreground image; Based on detecting that no human body region exists in the foreground image, marking that no intersection exists between the human body region in the distance image and the valid content region under the second space coordinates; Based on detecting that there is a human body region in the foreground image, second position information of the human body region is acquired, and the intersection of the human body region in the distance image and the valid content region under the second space coordinates is detected according to the second position information.

8. The projection device according to claim 2, characterized in that: The controller is also configured to: Detecting the projection mode of the projection device; If the projection mode is a screen projection mode, a step of detecting a grayscale value or a pixel value of a pixel point in the picture content is performed.

9. A projection control method, characterized in that: Applied to the projection device according to any one of claims 1 to 8, the method comprising: In the case where it is detected by the first image detection algorithm that the picture content includes a valid content area and an invalid content area, the coordinates of the valid content area are converted into spatial coordinates; wherein the grayscale values ​​or pixel values ​​of consecutive rows and / or consecutive columns of pixels in the invalid content area are the same, and the grayscale values ​​or pixel values ​​of the pixels are lower than a first threshold; If it is detected based on the first human body detection algorithm that there is an intersection between the human body area in the target image acquired by the image acquisition device and the valid content area under the spatial coordinates, the anti-eye-shooting process is executed; If it is detected based on the first human body detection algorithm that there is no intersection between the human body area in the target image and the valid content area under the spatial coordinates, the anti-eye-shooting process is not executed.

10. The projection control method according to claim 9, characterized in that: The controller is further configured to: before executing, when detecting through the first image detection algorithm that the screen content includes a valid content area and an invalid content area, converting the coordinates of the valid content area into space coordinates: Detecting the grayscale value or pixel value of a pixel point in the picture content; Based on detecting that the grayscale values ​​or pixel values ​​of at least a first number of consecutive rows and / or at least a first number of consecutive columns of pixels are the same, and the grayscale values ​​or pixel values ​​of the pixels are lower than a first threshold, marking the at least a first number of consecutive rows and / or at least a first number of consecutive columns of pixels as invalid content areas; An area other than the invalid content area in the screen content is marked as a valid content area.

Images