Projection device and projection method

Abstract

The application relates to the technical field of display equipment, and discloses a projection device and a projection method. The projection device comprises a projection assembly, a camera and a controller. The controller is configured to receive a first image sent by the camera, process the first image and obtain a second image. The pixel value of each pixel in the second image is a first pixel value or a second pixel value. If the area of a first connected region composed of the first pixel value in the second image is less than a first threshold area, the first pixel value in the first connected region is adjusted to the second pixel value to obtain a third image. A first rectangular region is determined in the third image based on the second pixel value in the third image, and the first rectangular region is the largest rectangular region composed of the second pixel value in the third image. The area of a curtain is determined from the first rectangular region according to a preset length-width ratio. The technical scheme of the application can improve the accuracy of the projection device in identifying the curtain.

Description

Technical Field

[0001] This application relates to the field of display device technology, and in particular to a projection device and projection method. Background Technology

[0002] A projection device is a display device that can project images or videos onto a screen. For example, a projection device can project content onto a screen by connecting to a computer, the Internet, a smartphone, a video signal source, etc.

[0003] Typically, projection screens come in various sizes and types. For different screens, the projection equipment needs to be adjusted accordingly before projection to ensure that the image to be projected is accurately projected onto the screen. For some conventional screens (e.g., four-sided screens), the projection equipment can easily determine the area of ​​the screen to project the content; however, for some unconventional screens (e.g., two-sided screens), the projection equipment may not be able to quickly and accurately determine the screen's position, thus affecting the accuracy of the projection. Summary of the Invention

[0004] To address the aforementioned issues, this application provides a projection device and projection method. This projection device is applicable to screens of different specifications and types, improving the accuracy of the projection device in identifying screens and thus projecting the content to be projected onto the screen more accurately. It also enhances the universality of the projection device for different screens.

[0005] On one hand, some embodiments of this application provide a projection device, including: a projection component, a camera device, and a controller coupled to the camera device and the projection component respectively. The projection component is configured to project an image to be projected onto a screen. The camera device is configured to capture an image of the area where the screen is located, obtaining a first image. The controller is configured to receive the first image sent by the camera device and process the first image to obtain a second image; wherein the pixel value of each pixel in the second image is a first pixel value or a second pixel value; if the area of ​​a first connected region composed of the first pixel values ​​in the second image is less than a first threshold area, the first pixel values ​​in the first connected region are adjusted to second pixel values ​​to obtain a third image; based on the second pixel values ​​in the third image, a first rectangular region is determined in the third image, the first rectangular region being the largest rectangular region composed of the second pixel values ​​in the third image; according to a preset aspect ratio, the area of ​​the screen is determined in the first rectangular region; based on the area of ​​the screen, the projection component is controlled to project the image to be projected onto the screen.

[0006] On the other hand, some embodiments of this application also provide a projection method, which includes: receiving a first image, the first image being an image of the area where a screen is located; processing the first image to obtain a second image; wherein, the pixel value of each pixel in the second image is a first pixel value or a second pixel value; if the area of ​​a first connected region composed of the first pixel values ​​in the second image is less than a first threshold area, adjusting the first pixel value in the first connected region to a second pixel value to obtain a third image; determining a first rectangular region in the third image based on the second pixel values ​​in the third image, the first rectangular region being the largest rectangular region composed of the second pixel values ​​in the third image; determining the area of ​​the screen in the first rectangular region according to a preset aspect ratio; and controlling a projection component to project the image to be projected onto the screen based on the area of ​​the screen.

[0007] As can be seen from the above technical solutions, the projection device and projection method provided in some embodiments of this application can, after receiving a first image captured by a camera device, process the first image to obtain a second image where the pixel value of each pixel is a first pixel value or a second pixel value; then, determine the relationship between the area of ​​a first connected region composed of the first pixel values ​​and the area of ​​a first threshold in the second image; when the area of ​​the first connected region is less than the area of ​​the first threshold, adjust the first pixel value in the first connected region to the second pixel value to obtain a third image; next, based on the second pixel values ​​in the third image, determine a first rectangular region in the third image, which is the largest rectangular region composed of the second pixel values ​​in the third image; then, according to a preset aspect ratio, determine the area of ​​the screen in the first rectangular region; finally, based on the area of ​​the screen, control the projection component to project the image to be projected onto the screen. Therefore, the projection device proposed in this application can more accurately identify the area of ​​the screen, thereby projecting the content to be projected onto the screen more accurately, and can adapt to different screens, improving the universality of the projection device for screens. Attached Figure Description

[0008] To more clearly illustrate the technical solution of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0009] Figure 1 A schematic diagram of a projection system provided in an embodiment of this application;

[0010] Figure 2 This is a schematic diagram of the structure of a projection device provided in an embodiment of this application;

[0011] Figure 3 A schematic diagram of the optical engine architecture in a projection device provided in an embodiment of this application;

[0012] Figure 4 A schematic diagram of the optical path in a projection device provided in an embodiment of this application;

[0013] Figure 5 A schematic diagram of a projection device provided in an embodiment of this application;

[0014] Figure 6 A schematic diagram of a screen provided for an embodiment of this application;

[0015] Figure 7 A schematic diagram of another type of screen provided in an embodiment of this application;

[0016] Figure 8 A schematic flowchart of a projection method provided in an embodiment of this application;

[0017] Figure 9 A schematic flowchart illustrating another projection method provided in an embodiment of this application;

[0018] Figure 10 A schematic flowchart illustrating another projection method provided in an embodiment of this application;

[0019] Figure 11 A schematic flowchart illustrating another projection method provided in an embodiment of this application;

[0020] Figure 12 A schematic flowchart illustrating another projection method provided in an embodiment of this application;

[0021] Figure 13 This is a flowchart illustrating another projection method provided in an embodiment of this application. Detailed Implementation

[0022] To make the objectives and implementation methods of this application clearer, the exemplary implementation methods of this application will be clearly and completely described below with reference to the accompanying drawings of the exemplary embodiments of this application. Obviously, the exemplary embodiments described are only some embodiments of this application, and not all embodiments.

[0023] It should be noted that the brief descriptions of terms in this application are only for the convenience of understanding the embodiments described below, and are not intended to limit the embodiments of this application. Unless otherwise stated, these terms should be understood in their ordinary and common meaning.

[0024] The terms "first," "second," "third," etc., used in the specification, claims, and accompanying drawings of this application are used to distinguish similar or related objects or entities, and do not necessarily imply a specific order or sequence, unless otherwise specified. It should be understood that such terms are interchangeable where appropriate.

[0025] The terms “comprising” and “having”, and any variations thereof, are intended to cover but not exclude inclusion, for example, a product or device that includes a range of components is not necessarily limited to all of the components that are clearly listed, but may include other components that are not clearly listed or that are inherent to such product or device.

[0026] The term "module" refers to any known or subsequently 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.

[0027] The embodiments of this application can be applied to various types of projection devices. The following description will use a projector as an example to illustrate the projection device and the automatic focusing method.

[0028] Figure 1 This is a schematic diagram of a projection system provided in some embodiments of this application. Figure 2 This is a schematic diagram of the structure of a projection device provided in some embodiments of this application.

[0029] In some embodiments, refer to Figure 1 The projection system may include a projection device 1 and a projection screen 2. The projection device 1 is placed in a first position, and the projection screen 2 is fixed in a second position, such that the image projected by the projection device 1 matches the image projected by the projection screen 2. (See reference...) Figure 2 The projection device 1 includes a laser light source 100, an optical engine 200, and a lens 300. The laser light source 100 provides illumination to the optical engine 200, which modulates the light beam and outputs it to the lens 300 for imaging, projecting it onto a projection medium 400 to form a projected image. In some examples, the projection medium 400 can also be a projection screen 2.

[0030] In some embodiments, the laser source 100 of the projection device 1 includes a laser assembly and an optical lens assembly. The beam emitted by the laser assembly can pass through the optical lens assembly to provide illumination for the optical engine. For example, the optical lens assembly requires a high level of environmental cleanliness and airtightness; while the chamber in which the laser assembly is installed can be sealed with a lower level of dustproof sealing to reduce sealing costs.

[0031] In some embodiments, the optical engine 200 of the projection device 1 may include a blue optical engine, a green optical engine, and a red optical engine, and may also include a heat dissipation system, a circuit control system, etc. It should be noted that in some embodiments, the light-emitting component of the projector may also be implemented using an LED light source.

[0032] Figure 3This is a schematic diagram of the circuit architecture of a projection device provided in some embodiments of this application. In some embodiments, the projection device 1 may include a display control circuit 10, a laser light source 100, at least one laser driving component 30, and at least one brightness sensor 40; the laser light source 100 may include at least one laser corresponding to at least one laser driving component 30. Here, "at least one" refers to one or more, and "more than one" refers to two or more.

[0033] In some embodiments, the laser source 100 includes three lasers corresponding one-to-one with the laser driving assembly 30. These three lasers can be a blue laser 201, a red laser 202, and a green laser 203, respectively. The blue laser 201 emits blue laser light, the red laser 202 emits red laser light, and the green laser 203 emits green laser light. In some embodiments, the laser driving assembly 30 can be implemented as including multiple sub-laser driving assemblies, each corresponding to a laser of a different color.

[0034] The display control circuit 10 is used to output control signals (e.g., enable signals and current control signals) to the laser driver assembly 30 to drive the laser to emit light. For example, the display control circuit 10 is connected to the laser driver assembly 30 and is used to output at least one enable signal corresponding to one-to-one with the three primary colors of each frame in a multi-frame display image, transmitting the at least one enable signal to the corresponding laser driver assembly 30; and to output at least one current control signal corresponding to one-to-one with the three primary colors of each frame, transmitting the at least one current control signal to the corresponding laser driver assembly 30. For example, the display control circuit 10 can be a microcontroller unit (MCU), also known as a single-chip microcomputer. The current control signal can be a pulse width modulation (PWM) signal.

[0035] like Figure 3As shown, the display control circuit 10 can output a blue PWM signal B_PWM corresponding to the blue laser 201 based on the blue primary color component of the image to be displayed, a red PWM signal R_PWM corresponding to the red laser 202 based on the red primary color component of the image to be displayed, and a green PWM signal G_PWM corresponding to the green laser 203 based on the green primary color component of the image to be displayed. The display control circuit 10 can also output an enable signal B_EN corresponding to the blue laser 201 based on the illumination duration of the blue laser 201 during the driving cycle, an enable signal R_EN corresponding to the red laser 202 based on the illumination duration of the red laser 202 during the driving cycle, and an enable signal G_EN corresponding to the green laser 203 based on the illumination duration of the green laser 203 during the driving cycle.

[0036] The laser driver assembly 30 is connected to the corresponding laser and is used to provide a corresponding driving current to the laser it is connected to in response to the received enable signal and current control signal. Each laser is used to emit light under the drive current provided by the laser driver assembly 30.

[0037] For example, such as Figure 3 As shown, blue laser 201, red laser 202, and green laser 203 are respectively connected to laser driver assembly 30. Laser driver assembly 30 can provide corresponding drive current to blue laser 201 in response to the blue PWM signal B_PWM and enable signal B_EN sent by display control circuit 10. Blue laser 201 emits light under the drive of this drive current.

[0038] based on Figure 3 In the circuit architecture, the projection device 1 sets a brightness sensor 40 in the light output path of the laser light source 100, so that 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.

[0039] The display control circuit 10 can acquire the second brightness value corresponding to the driving current of each laser, and determine that the laser has a COD fault when the difference between the second brightness value and the first brightness value of the laser is greater than the difference threshold. Then the display control circuit can adjust the current control signal of the corresponding laser driving component until the difference is less than or equal to the difference threshold, thereby eliminating the COD fault of the blue laser. The projection device can eliminate the COD fault of the laser in a timely manner, reduce the damage rate of the laser, and improve the image display effect of the projection device 1.

[0040] Figure 4 This is a schematic diagram of the optical path of a projection device provided in some embodiments of this application.

[0041] In some embodiments, the laser light source 100 in the projection device 1 may include independently configured blue laser 201, red laser 202, and green laser 203. Therefore, the projection device 1 may also be referred to as a three-color projection device. Among them, the blue laser 201, red laser 202, and green laser 203 can all be modular lightweight (Mirai ConsoleLoader, MCL) packaged lasers, which are small in size and facilitate compact arrangement of the optical path.

[0042] like Figure 4 As shown, the optical engine 200 of the projection device 1 includes an optical component 210, which can modulate the beam provided by the laser light source 100 using the image signal of the image to be displayed, so as to obtain the projection beam.

[0043] Figure 5 This is a schematic diagram of a projection device provided for some embodiments of this application. For example... Figure 5 As shown, in some embodiments, the projection device 1 further includes a controller 50, which includes at least one of a central processing unit (CPU), a video processor, an audio processor, a graphics processing unit (GPU), a random access memory (RAM), a read-only memory (ROM), a first to an nth interface for input / output, a communication bus, etc.

[0044] In some embodiments, refer to Figure 5 The projection device 1 may also include a camera device 60, which is coupled to the controller 50 and is used to work in conjunction with the projection device 1 to adjust and control the projection process. For example, the camera device 60 configured in the projection device 1 can be a regular camera, a 3D camera, a binocular camera, or a depth camera. When the camera device 60 is a binocular camera, it specifically includes a left camera and a right camera; the binocular camera can acquire the image and playback content presented on the screen corresponding to the projection device 1, i.e., the projection surface, which is projected by the optical engine 200 built into the projection device 1.

[0045] In some embodiments, refer to Figure 5 The projection device 1 may also include a projection component 70, which in some examples may include... Figure 2The projection assembly 70 may include at least one of the following components: laser light source 100, optical engine 200, and lens 300; for example, the projection assembly 70 may include the laser light source 100, optical engine 200, and lens 300; or, the projection assembly 70 may have the function of at least one of the following components: laser light source 100, optical engine 200, and lens 300.

[0046] It should be noted that the embodiments of this application can be applied to various types of projection devices 1. For example, projection device 1 can be a projector. A projector is a projection device that can project images or videos onto a screen. Projectors can be connected to computers, cable TV networks, the Internet, Video Compact Discs (VCDs), Digital Versatile Disc Recordable (DVDs), game consoles, DV cameras, etc., through different interfaces to play corresponding video signals. Projectors are widely used in homes, offices, schools, and entertainment venues. Projection device 1 can also be other types of projection devices, and this application does not limit this.

[0047] Figure 6 This is a schematic diagram of a screen provided for some embodiments of this application. For example... Figure 7 As shown, the screen 21 may include a projection area 211 and an edge line 212. The projection area 211 is used to display the image to be projected by the projection component 70.

[0048] In some embodiments, the projection component 70 can project an image to be projected onto the screen 21. Exemplarily, the projection screen 2 includes the screen 21, or the screen 21 can be one implementation of the projection screen 2. The screen 21 can be used in settings such as movies, offices, home theaters, and large conferences to display images, video files, etc., projected by the projection component 70.

[0049] In some examples, the screen 21 can be set to different sizes according to actual needs. For example, in order to make the display effect more in line with the user's viewing habits, the aspect ratio of the screen 21 can be set to 16:9, or the aspect ratio of the screen 21 can be set to 4:3.

[0050] In other examples, the curtain 21 can also be configured with different edge lines 212 according to actual needs. (See reference...) Figure 7 The curtain 21 has dark edge lines 212 around its four edges; for example, all four edge lines 212 of the curtain 21 can be black. These dark edge lines 212 typically have a certain width; therefore, the edge lines 212 can also be referred to as edge bands. For example, they can also be... Figure 7The screen 21 shown is called a four-sided screen. Because the edges of the four-sided screen have relatively obvious edge lines 212, the projection device 1 can take advantage of this feature to stably, efficiently and accurately identify the four-sided screen in the environment, so as to achieve rapid screen entry even after the projection device 1 moves.

[0051] However, in addition to four-sided screens, there are other types of screens 21, such as two-sided screens. Figure 7 This application provides a schematic diagram of a double-sided screen, in which two edges have dark edge lines 212, while the other two edges do not have dark edge lines 212. For example, as... Figure 7 As shown, in a double-sided screen, the top and bottom edges can each have a black edge line 212 of a certain width, while the left and right edges do not have a dark edge line 212. Therefore, the four edges of the double-sided screen cannot form a closed quadrilateral (e.g., a rectangle). As a result, when the projection device 1 is projecting, it may not be able to accurately identify the position of the double-sided screen, or the projection device 1 may identify the double-sided screen as an obstacle, thus failing to accurately project the image to be projected onto the screen 21.

[0052] It should be noted that the double-sided screen can also have any two edges with dark edge lines, while the other two edges do not have dark edge lines; this application does not limit this. For example, the left and right edges of the double-sided screen each have black edge lines 212 of a certain width, while the top and bottom edges do not have edge lines, making it impossible to accurately identify the top and bottom edges of the double-sided screen.

[0053] To address the aforementioned issues, the projection device 1 proposed in this application embodiment can also accurately project content onto the area of ​​the screen 21 for screens of other specifications that are not four-sided screens (such as two-sided screens), thereby improving the universality of the projection device 1 for the screen 21.

[0054] Figure 8 A flowchart illustrating the projection process of a projection device projecting a projected image onto a screen, as provided in this application, is shown below. Figure 8 As shown, the projection process includes steps S810 to S860.

[0055] Step S810: Receive the first image, which is the image of the area where the screen 21 is located.

[0056] In some embodiments, the camera device 60 can obtain a first image by capturing images of the area where the screen 21 is located. For example, the first image may include various objects in the environment of the area where the screen 21 is located, such as walls, wall hangings, wallpaper, etc. In some examples, the first image captured by the camera device 60 may or may not be a color image. Some embodiments of this application are illustrated using the example of a color image captured by the camera device 60.

[0057] The camera device 60 sends the captured first image to the controller 50, and the controller 50 receives the first image.

[0058] Step S820: Process the first image to obtain a second image; wherein the pixel value of each pixel in the second image is either the first pixel value or the second pixel value.

[0059] After receiving the first image sent by the camera device 60, the controller 50 processes the first image accordingly. In some embodiments, the controller 50 may perform grayscale conversion, cropping, binarization, and other processing on the received first image to obtain a second image. The pixel value of each pixel in the obtained second image is either the first pixel or the second pixel; that is, the second image contains only two pixel values, i.e., the pixel values ​​in the second image are two different color pixel values, which is beneficial for the projection device 1 to recognize the screen 21.

[0060] For example, the first pixel value can be a pixel value of 0, and the second pixel value can be a pixel value of 255. In this way, the second image contains black pixels with a pixel value of 0 and white pixels with a pixel value of 255, thereby further improving the recognition accuracy of the screen 21.

[0061] In some embodiments, such as Figure 9 As shown, the process of processing the first image to obtain the second image in step S820 includes the following steps S910 to S930.

[0062] Step S910: Perform grayscale conversion on the first image to obtain the grayscale image corresponding to the first image.

[0063] Typically, the first image is a color image captured by the camera device 60. To more easily and accurately identify the area of ​​the backdrop 21 in the environmental factors within the first image, the controller 50 can perform grayscale conversion processing based on the acquired first image, converting the color first image into a corresponding grayscale image. For example, the controller 50 can adjust the grayscale value of each pixel in the first image according to preset conditions and a preset transformation relationship to obtain a grayscale image corresponding to the first image. Compared to the first image, the grayscale image corresponding to the first image has better image quality and a better display effect.

[0064] Step S920: The grayscale image corresponding to the first image is cropped to obtain the cropped image, which includes the screen 21.

[0065] Typically, the first image is relatively large; for example, it could be an image of the entire wall including the area of ​​curtain 21. To more quickly locate the area of ​​curtain 21, the controller 50 can crop the grayscale image corresponding to the first image to obtain the cropped image. The size of the cropped image is smaller than the size of the grayscale image corresponding to the first image, and the cropped image is a portion of the area of ​​the first image that includes curtain 21.

[0066] For example, the controller 50 can crop the grayscale image corresponding to the first image according to preset parameters. These preset parameters can be parameters pre-set inside the projection device 1, or they can be default parameters in the projection device 1. In some examples, the preset parameters can be set based on the internal and external parameters of the optical engine 200. For example, if the preset parameter in the projection device 1 is 50px... 50px, when the size of the grayscale image corresponding to the first image is 100px. At 100px, controller 50 can be at 100px. A 50px section, including the area of ​​the backdrop 21, is cropped from the grayscale image corresponding to the first 100px image. A 50px image is used as the cropped image.

[0067] For example, the controller 50 may also crop the first image based on the maximum projection area of ​​the projection device 1. In some examples, the maximum projection area of ​​the projection device 1 is related to the device type of the projection device 1, and the area of ​​the maximum projection area may be different for different types of projection devices 1. For example, the projection device 1 may crop an area of ​​the same size as its maximum projection area from the grayscale image corresponding to the first image as the cropped image.

[0068] It should be noted that this application does not limit the execution order of steps S910 and S920. For example, step S920 can be executed first to crop the first image, and then step S910 can be executed to convert the cropped first image to grayscale.

[0069] Step S930: Binarize the cropped image to obtain the second image.

[0070] In some examples, binarization of the cropped image involves setting the pixel value (also known as grayscale value) of each pixel in the cropped image to either 0 or 255, resulting in a visual effect where the cropped image displays only black and white. The pixels in the resulting second image after binarization have only two pixel values: either a first pixel value (e.g., pixel value 0) or a second pixel value (e.g., pixel value 255), thus ensuring that the second image contains only two colors (e.g., black and white). Therefore, by binarizing the cropped image, the accuracy of the projection device 1 in recognizing areas of the screen 21 can be further improved.

[0071] For example, the controller 50 may be configured with a preset pixel threshold, and the pixel values ​​of each pixel in the cropped image are compared and divided based on the preset pixel threshold. When the pixel value of a pixel in the cropped image is less than the preset pixel threshold, the pixel value of that pixel is set as a first pixel value; when the pixel value of a pixel in the cropped image is greater than or equal to the preset pixel threshold, the pixel value of that pixel is set as a second pixel value.

[0072] In some examples, the preset pixel threshold can be obtained through multiple tests; for example, the preset pixel threshold can be 100. That is, when the pixel value of a pixel in the cropped image is less than 100, the pixel value is adjusted to the first pixel value (e.g., pixel value 0); when the pixel value of a pixel in the cropped image is greater than or equal to 100, the pixel value is adjusted to the second pixel value (e.g., pixel value 255). For example, for a double-sided screen, after binarization, its top and bottom edge lines 212 can be displayed as black (pixel value 0), and its projection area 211 can be displayed as white (pixel value 255). It should be noted that for a double-sided screen, its left and right edges may appear white, thus the exact area of ​​the screen 21 cannot be determined, and step S830 needs to be performed for further determination.

[0073] Step S830: If the area of ​​the first connected region composed of the first pixel values ​​in the second image is less than the area of ​​the first threshold, adjust the first pixel values ​​in the first connected region to the second pixel values ​​to obtain the third image.

[0074] In some embodiments, pixels with the first pixel value in the second image can form multiple first connected regions, and pixels with the second pixel value can form multiple second connected regions. The second connected regions include the area of ​​the curtain 21.

[0075] Specifically, the first connected region and the second connected region can be closed shapes. For example, the first connected region can consist entirely of black pixels, meaning that the pixel value of each pixel in the first connected region is 0; the second connected region can consist entirely of white pixels, meaning that the pixel value of each pixel in the second connected region is 255.

[0076] In some examples, the number of first connected regions and second connected regions may be one, or the number of first connected regions and second connected regions may be greater than one; if the number of first connected regions and second connected regions is multiple, the size (e.g., the area) of each first connected region or each second connected region may be the same or different, and this application does not limit this.

[0077] For example, the first threshold area can be obtained through extensive testing. For instance, the first threshold area can be one-quarter of the area of ​​the largest first connected region among a plurality of first connected regions. The first threshold area can be used to indicate whether the first connected region affects the projection effect of the projection device 1, or in other words, whether the first connected region might be part of the projection area of ​​the projection device 1.

[0078] In some examples, when the area of ​​the first connected region formed by the first pixel values ​​is smaller than the area of ​​the first threshold, the first connected region is considered to be small, and the first connected region does not contain any obstacles that would affect the projection of the projection device 1. Therefore, in order to avoid areas (or patches) with abrupt color changes in the screen 21, the pixel values ​​(e.g., the first pixel values) of these abrupt color changes can be processed. For example, the pixel values ​​of this part (e.g., pixel value 0) can be adjusted to the second pixel value (e.g., pixel value 255).

[0079] If the area of ​​the first connected region is greater than the area of ​​the first threshold, this part may be an obstacle region and therefore cannot be ignored. In this case, the pixel values ​​in the first connected region can be left unchanged, i.e., the first pixel values ​​can be maintained.

[0080] After processing in step S830, a third image is obtained, which includes one or more second connected regions. For example, in the third image, the largest second connected region may contain the region of the curtain 21.

[0081] Step S840: Based on the second pixel value in the third image, a first rectangular region is determined in the third image. The first rectangular region is the largest rectangular region in the third image composed of the second pixel value.

[0082] As can be seen from the above step S830, the second pixel values ​​form multiple second connected regions. First, the largest second connected region is determined among these multiple second connected regions; then, a first rectangular region is determined within the largest second connected region. That is, the first rectangular region can be the largest rectangular region formed by the second pixel values ​​in the second connected regions.

[0083] It should be noted that the first rectangular area can also be called the first rectangle. Typically, the screen 21 is rectangular, and a rectangular projection area is more in line with human viewing habits, resulting in a better viewing experience. Therefore, the largest rectangular area determined in the second connected region may include the screen 21, which is helpful in further defining the area of ​​the screen 21.

[0084] Step S850: Determine the area of ​​the curtain 21 in the first rectangular area according to the preset aspect ratio.

[0085] For example, the preset aspect ratio can be set according to the length and width parameters of the screen 21, user needs, or viewing effect. For example, the preset aspect ratio can be 16:9, or it can be 4:3. It should be noted that the length and width involved in this application are used to indicate the two adjacent sides of the first rectangular area. The length and width can also be referred to as width and height. The preset aspect ratio in this application can also be referred to as the preset aspect ratio. This application does not limit the specific aspect ratio.

[0086] In some embodiments, such as Figure 10 As shown, in step S850, determining the area of ​​the curtain 21 from the first rectangular area according to the preset aspect ratio includes the following steps S1010 to S1030.

[0087] Step S1010: Calculate the position of the center point of the first rectangular region based on the positions of the four corner points of the first rectangular region.

[0088] In some examples, once the controller 50 determines the first rectangular region, it can obtain the coordinates of the four corner points of the first rectangular region (hereinafter also referred to as the first rectangle). For example, the coordinates of the four corner points of the first rectangle can be represented as A(x1, y1), B(x1, y2), C(x2, y1), and D(x2, y2), respectively.

[0089] The coordinates of the center point of the first rectangle can be calculated based on the coordinates of its four corner points. For example, if the coordinates of the center point of the first rectangle are O(x3, y3), then the coordinates of the center point of the first rectangle are: x3 = (x1 + x2) / 2, y3 = (y1 + y2) / 2, which is O((x1 + x2) / 2, (y1 + y2) / 2).

[0090] Step S1020: Based on the center point position and according to the preset aspect ratio, determine the positions of the four corner points of the second rectangular region from the first rectangular region.

[0091] In some embodiments, the center point of the second rectangular region is the same as the center point of the first rectangular region, and the aspect ratio of the second rectangular region is a preset aspect ratio.

[0092] In other words, after determining the coordinates of the center point of the first rectangular area, the coordinates of the center point of the second rectangular area are determined. The center point of the first rectangular area is taken as the center point of the second rectangular area, and the aspect ratio of the second rectangular area is taken as the aspect ratio of the second rectangular area. The second rectangular area (which can also be referred to as the second rectangle) is determined. At the same time, the coordinates of the four corner points of the second rectangular area are determined.

[0093] Specifically, the length (or width) of the first rectangle is W1 = x2 - x1, and the width (or height) is H1 = y2 - y1. When the length of the second rectangle is W2 and the width is H2, taking a preset aspect ratio of 16:9, i.e., W2 / H2 = 16:9, as an example:

[0094] When W1 / H1 > 16 / 9, W2 = H1 (16 / 9), H2 = H1; when W1 / H1 ≤ 16 / 9, H2 = W1 (9 / 16), W2=W1.

[0095] The coordinates of the four corner points of the second rectangle can be represented as: E(x3-W2 / 2, y3-H2 / 2), F(x3+W2 / 2, y3-H2 / 2), G(x3+W2 / 2, y3+H2 / 2), H(x3-W2 / 2, y3+H2 / 2).

[0096] Step S1030: Determine the area of ​​the curtain 21 based on the positions of the four corner points of the second rectangular area.

[0097] Once the coordinates of the four corner points of the second rectangle are determined, the area of ​​the curtain 21 can be determined based on the coordinates of the four corner points of the second rectangle.

[0098] In some embodiments, such as Figure 11 As shown, in step S1030, determining the area of ​​the curtain 21 based on the positions of the four corner points of the second rectangular area includes the following steps S1110 to S1140.

[0099] Step S1110: Filter the cropped image to obtain the fourth image.

[0100] After completing step S920 in the above embodiment, the cropped image can be filtered. For example, mean filtering can be applied to the cropped image. Mean filtering can smooth the cropped image to avoid the influence of irrelevant corner points. The image after filtering is the fourth image.

[0101] Step S1120: Determine the positions of multiple projection points based on the corner positions of the fourth image.

[0102] For example, after obtaining the fourth image, multiple projection point positions can be determined in the fourth image using corner detection methods. In some examples, OpenCV functions can be used to obtain the coordinates of each corner point in the fourth image, and the coordinates of each corner point are the coordinates of multiple projection points in the projection area of ​​projection device 1. That is, the coordinates of multiple projection points can determine the projection area of ​​projection device 1, and projection device 1 needs to project the image to be projected onto its projection area, which includes the area of ​​screen 21.

[0103] Step S1130: Among the multiple projection point positions, the projection point position that is closest to the four corner points of the second rectangular area is determined as the target projection point position.

[0104] After determining the coordinates of multiple projection points in the fourth image and obtaining the coordinates of the four corner points of the second rectangular region through step S1020, in some examples, if there are coordinates among the multiple projection points that coincide with the coordinates of the four corner points of the second rectangular region, then the coordinates among the multiple projection points that coincide with the coordinates of the four corner points of the second rectangular region are determined as the target projection point coordinates. If there are no coordinates among the multiple projection points that coincide with the coordinates of the four corner points of the second rectangular region, then the coordinates of the projection point closest to the coordinates of the four corner points of the second rectangular region can be determined as the target projection point position.

[0105] For example, among multiple projection point coordinates, a traversal method can be used to determine the projection point coordinates that coincide with the coordinates of the four corner points of the second rectangular area, or the projection point coordinates that are closest to the coordinates of the four corner points of the second rectangular area.

[0106] Step S1140: The area formed by the target projection point positions is determined as the area of ​​the screen 21.

[0107] The area formed by the coordinates of the target projection point is the area of ​​the screen 21. In other words, the coordinates of the target projection point are the coordinates of the four corner points of the screen 21.

[0108] In step S860, based on the area of ​​the screen 21, the projection component 70 is controlled to project the image to be projected onto the screen 21.

[0109] After determining the area of ​​the screen 21, the controller 50 can control the projection component 70 to project the image to be projected onto the screen 21, or the controller 50 can control the projection component 70 to project the image to be projected onto the area of ​​the screen 21.

[0110] Figure 12 A flowchart illustrating yet another projection method provided in some embodiments of this application. For example... Figure 12 As shown, the projection method may further include steps S1211 to S1223.

[0111] Step S1211: Receive the first image.

[0112] The first image is the image of the area where the screen 21 is located. This step S1211 is similar to step S810 in the above embodiment, and will not be described again here.

[0113] Step S1212: Perform grayscale conversion on the first image to obtain the grayscale image corresponding to the first image.

[0114] This step is similar to step S910 in the above embodiment, and will not be described again here.

[0115] After executing step S1212, steps S1213 and S1220 can be executed separately. Step S1213 can be executed simultaneously with step S1220, and step S1231 can be executed before or after step S1220. This application does not limit the execution order of steps S1213 and S1220.

[0116] Step S1213: Crop the grayscale image corresponding to the first image to obtain the cropped image.

[0117] The captured image includes the area of ​​the screen 21. This step S1213 is similar to step S920 in the above embodiment, and will not be described again here.

[0118] Step S1214: Binarize the cropped image to obtain the second image.

[0119] This step is similar to step S930 in the above embodiment, and will not be described again here.

[0120] Step S1215: Determine whether the area of ​​the first connected region composed of the first pixel values ​​in the second image is less than the area of ​​the first threshold.

[0121] If the area of ​​the first connected region is less than the area of ​​the first threshold, continue to execute step S1216; if the area of ​​the first connected region is greater than or equal to the area of ​​the second threshold, continue to execute step S1217.

[0122] Step S1216: Adjust the first pixel value in the first connected region to the second pixel value to obtain the third image.

[0123] This step is similar to step S830 in the above embodiment, and will not be described again here.

[0124] Step S1217: Determine a first rectangular region in the third image based on the second pixel value in the third image.

[0125] The first rectangular region is the largest rectangular region in the third image composed of the second pixel values. This step S1217 is similar to step S840 in the above embodiment, and will not be described again here.

[0126] Step S1218: Calculate the position of the center point of the first rectangular region based on the positions of the four corner points of the first rectangular region.

[0127] This step is similar to step S1010 in the above embodiment, and will not be described again here.

[0128] Step S1219: Based on the center point position and according to the preset aspect ratio, determine the positions of the four corner points of the second rectangular region from the first rectangular region.

[0129] This step is similar to step S1020 in the above embodiment, and will not be described again here. After step S1219, continue to execute step S1222.

[0130] Step S1220: Filter the cropped image to obtain the fourth image.

[0131] This step is similar to step S1110 in the above embodiment, and will not be described again here. It should be noted that step S1220 can be executed at any time between step S1212 and step S1222.

[0132] Step S1221: Determine the positions of multiple projection points based on the corner positions of the fourth image.

[0133] This step is similar to step S1120 in the above embodiment, and will not be described again here. After step S1221, step S1222 is executed.

[0134] Step S1222: Determine the target projection point position from among the multiple projection point positions that is closest to the four corner points of the second rectangular area.

[0135] This step is similar to step S1130 in the above embodiment, and will not be described again here.

[0136] Step S1223: The area formed by the target projection point positions is determined as the area of ​​the screen 21.

[0137] This step is similar to step S1140 in the above embodiment, and will not be described again here.

[0138] In some embodiments, step S860 further includes: comparing the area of ​​the region of the screen 21 with the second threshold area; if the area of ​​the first projection region is greater than or equal to the second threshold area, then based on the region of the screen 21, controlling the projection component 70 to project the image to be projected onto the screen 21.

[0139] Specifically, by comparing the area of ​​screen 21 (also referred to as the area of ​​screen 21) with the second threshold area, the overlap rate between the projection area of ​​projection device 1 and screen 21 can be indicated, or in other words, the coverage rate of the projection area of ​​projection device 1 on screen 21. If the area of ​​screen 21 is greater than or equal to the second threshold area, it indicates that the projection area of ​​projection device 1 can cover the area of ​​screen 21 well. In this case, it indicates that projection device 1 has successfully entered the screen, and projection component 70 can project the image to be projected onto screen 21 well. If the area of ​​screen 21 is less than the second threshold area, it indicates that the projection area of ​​projection device 1 cannot cover the area of ​​screen 21 well. In this case, it indicates that projection device 1 has failed to enter the screen, and projection device 1 needs to re-enter calibration or other operations to achieve further projection.

[0140] For example, the setting of the second threshold area is related to the device type of the projection device 11. For instance, to obtain a better viewing effect, the second threshold area can be set to 85% of the maximum projection area of ​​the projection device 1. It should be noted that the second threshold area can also be set according to actual needs, and this application does not limit it in this regard.

[0141] Figure 13 A flowchart of yet another projection method provided in some embodiments of this application, such as Figure 13 As shown, the projection method includes steps S1310 to S1370.

[0142] Step S1310: Receive the screen opening command.

[0143] For example, a screen entry switch can be configured on the projection device 1. This screen entry switch can be a button switch or a touch switch; this application does not limit the specific type of switch. In some examples, when a user triggers the screen entry switch, the screen entry switch sends a screen entry opening command to the controller 50, and the controller 50 receives the screen entry opening command.

[0144] Step S1320: Determine whether the second image contains a closed rectangle.

[0145] For example, the second image can be obtained by executing steps S1211 to S1214 in the above embodiments; by determining whether there is a closed rectangle in the second image, the edge line 212 of the screen 21 can be obtained, for example, it can be determined whether the screen 21 is a four-sided screen or a two-sided screen.

[0146] If the second image contains a closed rectangle, proceed to step S1330; if the second image does not contain a closed rectangle, continue to proceed to step S1340.

[0147] In step S1330, the projection component 70 is controlled to project the image to be projected onto the screen 21 using a four-sided projection method.

[0148] If the second image contains a closed rectangle, it means that screen 21 is a four-sided screen. In this case, projection can be performed according to the projection method of a four-sided screen.

[0149] Step S1340: Enter the control process for bilateral screen entry.

[0150] At this time, the controller 50 can execute steps S810 to S860 in the above embodiment to obtain the area of ​​the curtain 21.

[0151] Step S1350: Determine whether the area of ​​the curtain 21 is greater than or equal to the area of ​​the second threshold.

[0152] If the area of ​​the curtain 21 is greater than or equal to the area of ​​the second threshold, proceed to step S1360; if the area of ​​the curtain 21 is less than the area of ​​the second threshold, proceed to step S1370.

[0153] Step S1360: Projection device 1 successfully entered the screen.

[0154] Step S1370: Projection device 1 failed to enter the screen.

[0155] In summary, the projection device 1 and projection method provided in this application can, after receiving a first image captured by the camera device 60, process the first image to obtain a second image where each pixel has a first pixel value or a second pixel value; then, determine the relationship between the area of ​​the first connected region composed of the first pixel values ​​and the area of ​​the first threshold in the second image; when the area of ​​the first connected region is less than the area of ​​the first threshold, adjust the first pixel value in the first connected region to the second pixel value to obtain a third image; next, based on the second pixel values ​​in the third image, determine a first rectangular region in the third image, which is the largest rectangular region composed of the second pixel values ​​in the third image; then, according to a preset aspect ratio, determine the area of ​​the screen 21 in the first rectangular region; finally, based on the area of ​​the screen 21, control the projection component 70 to project the image to be projected onto the screen 21. Therefore, the projection device 1 proposed in this application can more accurately identify the area of ​​the screen 21, thereby projecting the content to be projected onto the screen 21 more accurately, and the projection device 1 provided in this application has higher universality for the screen 21.

[0156] Similar parts between the embodiments provided in this application can be referred to mutually. The specific implementation methods provided above are only a few examples under the overall concept of this application and do not constitute a limitation on the scope of protection of this application. For those skilled in the art, any other implementation methods extended from the solution of this application without creative effort shall fall within the scope of protection of this application.

Claims

1. A projection device, characterized in that, include: The projection component is configured to project an image onto a screen. The camera device is configured to capture an image of the area where the screen is located, thereby obtaining a first image; The controller, coupled to both the camera device and the projection assembly, is configured to: The first image is acquired, and the first image is processed to obtain the second image; wherein, the pixels in the second image have two types of pixel values, and the pixel value of each pixel in the second image is either the first pixel value or the second pixel value; If the area of ​​the first connected region composed of the first pixel values ​​in the second image is smaller than the area of ​​the first threshold, the first pixel values ​​in the first connected region are adjusted to the second pixel values ​​to obtain the third image; Based on the second pixel value in the third image, a first rectangular region is determined in the third image, and the first rectangular region is the largest rectangular region in the third image composed of the second pixel value; The area of ​​the curtain is determined within the first rectangular region according to the preset aspect ratio; Based on the area of ​​the screen, the projection component is controlled to project the image to be projected onto the screen.

2. The projection device according to claim 1, characterized in that, The controller, based on a preset aspect ratio, determines the area of ​​the screen within the first rectangular region, and is further configured to: Calculate the position of the center point of the first rectangular region based on the positions of the four corner points of the first rectangular region; Based on the center point position of the first rectangular region, and according to the preset aspect ratio, the four corner points of the second rectangular region are determined from the first rectangular region; wherein, the center point position of the second rectangular region is the same as the center point position of the first rectangular region, and the aspect ratio of the second rectangular region is the preset aspect ratio; The area of ​​the curtain is determined based on the positions of the four corner points of the second rectangular area.

3. The projection device according to claim 2, characterized in that, The controller processes the first image to obtain a second image, which is further configured as follows: Perform grayscale conversion on the first image to obtain the grayscale image corresponding to the first image; The grayscale image corresponding to the first image is cropped to obtain the cropped image; wherein, the cropped image includes the curtain; The cropped image is binarized to obtain the second image.

4. The projection device according to claim 3, characterized in that, The controller, based on the positions of the four corner points of the second rectangular region, determines the area of ​​the curtain, and is further configured to: The cropped image is filtered to obtain the fourth image; Based on the corner positions in the fourth image, determine the positions of multiple projection points; Among the plurality of projection point positions, the projection point position that is closest to the four corner points of the second rectangular region is determined as the target projection point position; The area formed by the locations of the target projection points is defined as the area of ​​the screen.

5. The projection device according to any one of claims 1-4, characterized in that, The controller, which executes the region based on the screen and controls the projection component to project the image to be projected onto the screen, is further configured to: Compare the area of ​​the screen region with the area of ​​the second threshold; If the area of ​​the screen is greater than or equal to the second threshold area, then based on the area of ​​the screen, the projection component is controlled to project the image to be projected onto the screen.

6. A projection method, characterized in that, The method includes: Acquire a first image, which is an image of the area where the curtain is located; The first image is processed to obtain a second image; wherein the pixels in the second image have two types of pixel values, and the pixel value of each pixel in the second image is either a first pixel value or a second pixel value; If the area of ​​the first connected region composed of the first pixel values ​​in the second image is smaller than the area of ​​the first threshold, the first pixel values ​​in the first connected region are adjusted to the second pixel values ​​to obtain the third image; Based on the second pixel value in the third image, a first rectangular region is determined in the third image, and the first rectangular region is the largest rectangular region in the third image composed of the second pixel value; The area of ​​the curtain is determined within the first rectangular region according to the preset aspect ratio; Based on the area of ​​the screen, the projection component is controlled to project the image to be projected onto the screen.

7. The method according to claim 6, characterized in that, The step of determining the area of ​​the curtain from the first rectangular area according to a preset aspect ratio further includes: Calculate the position of the center point of the first rectangular region based on the positions of the four corner points of the first rectangular region; Based on the center point position of the first rectangular region, and according to the preset aspect ratio, the four corner points of the second rectangular region are determined from the first rectangular region; wherein, the center point position of the second rectangular region is the same as the center point position of the first rectangular region, and the aspect ratio of the second rectangular region is the preset aspect ratio; The area of ​​the curtain is determined based on the positions of the four corner points of the second rectangular area.

8. The method according to claim 7, characterized in that, The step of processing the first image to obtain the second image further includes: Perform grayscale conversion on the first image to obtain the grayscale image corresponding to the first image; The grayscale image corresponding to the first image is cropped to obtain the cropped image; the cropped image includes the curtain. The cropped image is binarized to obtain the second image.

9. The method according to claim 8, characterized in that, The step of determining the area of ​​the curtain based on the positions of the four corner points of the second rectangular area further includes: The cropped image is filtered to obtain the fourth image; Based on the corner positions of the fourth image, determine the positions of multiple projection points; Among the plurality of projection point positions, the projection point position that is closest to the four corner points of the second rectangular region is determined as the target projection point position; The area formed by the locations of the target projection points is defined as the area of ​​the screen.

10. The method according to any one of claims 6-9, characterized in that, The step of controlling the projection component to project the image to be projected onto the screen based on the area of ​​the screen further includes: Compare the area of ​​the screen region with the area of ​​the second threshold; If the area of ​​the screen region is greater than or equal to the second threshold area, the projection component is controlled to project the image to be projected onto the screen based on the area of ​​the screen.

Images