Projection equipment and laser projection method

Abstract

The embodiment of the invention discloses projection equipment and a laser projection method. The method comprises the following steps: acquiring a projection medium image; determining a reference area and a correction area in the projection medium image; determining a correction graph card based on a reference area and a correction area in the projection medium image; projecting a correction graphic card and shooting a projection correction image; and when the similarity between the color of the correction area in the projection correction image and the color of the reference area is higher than a preset similarity, adjusting the pixel value of the correction area in the to-be-projected image according to the color of the correction area in the correction graph card. The reference area and the correction area can be determined through the shot projection medium image, the color-variable correction graph card is projected so that the color of the reference area and the color of the correction area in the projection correction image are the same, and the color of the pixel point is adjusted according to the color of the correction area of the correction graph card. The whole picture is not influenced by the splicing color of the projection medium background, environmental factors and subjective factors, and the projection effect is kept consistent.

Description

TECHNICAL FIELD

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

[0002] The imaging principle of the projection equipment is to separate a video signal into RGB three-primary color image signals, control RGB three-primary color semiconductor laser generators to emit laser beams with corresponding intensities respectively, and project the laser beams onto a screen after modulation output and signal synchronization control, so that a user can watch a projection picture. With the increasing demand for home entertainment and office, laser projection technology is gradually welcomed in the market. However, when the traditional projection equipment projects on different color walls, the image quality is often affected by the color of the wall, resulting in color distortion and image quality degradation.

[0003] The projection equipment has begun to introduce a wall color self-adaptation function. The technical principle of the wall color self-adaptation is to preset multiple common colors in the equipment, set DLP (Digital Light Processing) parameters for each common color, then detect the wall color through a camera, match the wall color with the preset color, and adjust the picture display effect. However, for a wall with multiple colors spliced, if the DLP parameters are used to adjust the projection picture, the display effect will be different when projected on different color walls, resulting in poor projection effect. SUMMARY

[0004] Some embodiments of the present application provide a projection equipment and a laser projection method. The color of the reference area and the correction area in the projection correction image can be made the same by projecting a correction picture card with variable colors according to the projection medium image captured by the camera, and the color of the pixel points is adjusted according to the color of the correction area of the correction picture card. As a result, the entire picture is not affected by the background splicing color of the projection medium, environmental factors and subjective factors, and the projection effect remains consistent.

[0005] In a first aspect, some embodiments of the present application provide a projection equipment, comprising:

[0006] An optical machine configured to project a projection picture to a projection medium;

[0007] A controller coupled with the optical machine and configured to:

[0008] Obtain a projection medium image captured by an image collector;

[0009] Determine a reference area and a correction area in the projection medium image, wherein the color of the reference area and the correction area in the projection medium image is different;

[0010] determine a correction chart based on the reference region and the correction region in the projection medium image, wherein a color of the reference region in the correction chart is different from a color of the correction region;

[0011] control the optical machine to project the correction chart to the projection medium and control the image collector to capture a projection correction image corresponding to the correction chart;

[0012] in a case where a similarity between the color of the correction region and the color of the reference region in the projection correction image is higher than a preset similarity, adjust a pixel value of the correction region in the image to be projected according to the color of the correction region in the correction chart, and control the optical machine to project the adjusted image to be projected to the projection medium.

[0013] In some embodiments, the controller performing the determining the reference region and the correction region in the projection medium image is further configured to:

[0014] perform image processing on the projection medium image to obtain a color demarcation line;

[0015] determine the reference region and the correction region in the projection medium image according to the color demarcation line.

[0016] In some embodiments, the controller performing the determining the reference region and the correction region in the projection medium image according to the color demarcation line is further configured to:

[0017] control the optical machine to project a preset chart to the projection medium and control the image collector to capture a projection region image corresponding to the preset chart;

[0018] determine a plurality of color regions in the projection region image based on the color demarcation line;

[0019] calculate a color similarity between a color corresponding to the color region and a preset color;

[0020] determine a color region with the smallest color similarity among the plurality of color regions as the reference region, and determine color regions other than the reference region as the correction region.

[0021] In some embodiments, the controller performing the calculating the color similarity between the color corresponding to the color region and the preset color is further configured to:

[0022] convert the color corresponding to the color region and the preset color from a first color space to a second color space, wherein the first color space is different from the second color space;

[0023] calculate a distance between the color corresponding to the color region and the preset color in the second color space;

[0024] calculate a color similarity between a color corresponding to the color region and a preset color based on the distance.

[0025] In some embodiments, the controller is further configured to determine a reference region and a correction region in the projection medium image according to the color boundary line, and the controller is further configured to:

[0026] determine a plurality of color regions in the projection medium image based on the color boundary line;

[0027] calculate an area or a number of pixels of the color region;

[0028] determine a color region with a largest area or a largest number of pixels in the plurality of color regions as the reference region, and determine color regions other than the reference region as the correction region.

[0029] In some embodiments, the controller is further configured to adjust a pixel value of the correction region in the image to be projected according to a color of the correction region in the correction chart, and the controller is further configured to:

[0030] normalize the color value of the correction region in the correction chart to obtain a color reflectance;

[0031] adjust the pixel value of the correction region in the image to be projected according to the color reflectance.

[0032] In some embodiments, the controller is further configured to adjust a pixel value of the correction region in the image to be projected according to the color reflectance, and the controller is further configured to:

[0033] perform a gamma transformation on a pixel point of the correction region in the image to be projected to obtain a first color component of the pixel point;

[0034] adjust the first color component based on the color reflectance to obtain a second color component;

[0035] perform an inverse gamma transformation on the second color component to obtain an adjusted pixel value of the pixel point of the correction region.

[0036] In some embodiments, the controller is configured to:

[0037] in a case where a color similarity between the color of the correction region and the color of the reference region in the projection correction image is equal to or lower than a preset similarity, change the color of the correction region in the correction chart;

[0038] control the optical engine to project the changed correction chart to the projection medium and control the image collector to capture a projection correction image corresponding to the changed correction chart.

[0039] In a second aspect, some embodiments of the present application provide a laser projection method, comprising:

[0040] obtaining a projection medium image captured by an image collector;

[0041] determining a reference region and a correction region in the projection medium image, wherein the reference region and the correction region in the projection medium image are different in color;

[0042] determining a correction chart based on the reference region and the correction region in the projection medium image, wherein the reference region and the correction region in the correction chart are different in color;

[0043] controlling the optical machine to project the correction chart onto the projection medium and controlling the image collector to capture a projection correction image corresponding to the correction chart;

[0044] in a case where the color of the correction region in the projection correction image is more similar to the color of the reference region than a preset similarity, adjusting a pixel value of the correction region in a to-be-projected image according to the color of the correction region in the correction chart, and controlling the optical machine to project the adjusted to-be-projected image onto the projection medium.

[0045] In a third aspect, some embodiments of the present application provide a computer readable storage medium, which stores a computer program for executing the above laser projection method.

[0046] Some embodiments of the present application provide a projection device and a laser projection method. A projection medium image captured by an image collector is obtained. A reference region and a correction region in the projection medium image are determined, wherein the reference region and the correction region in the projection medium image are different in color. A correction chart is determined based on the reference region and the correction region in the projection medium image, wherein the reference region and the correction region in the correction chart are different in color. The optical machine is controlled to project the correction chart onto the projection medium, and the image collector is controlled to capture a projection correction image corresponding to the correction chart. In a case where the color of the correction region in the projection correction image is more similar to the color of the reference region than a preset similarity, a pixel value of the correction region in a to-be-projected image is adjusted according to the color of the correction region in the correction chart, and the optical machine is controlled to project the adjusted to-be-projected image onto the projection medium. The present application can determine the reference region and the correction region through the captured projection medium image, project the correction chart with variable color to make the color of the reference region and the color of the correction region in the projection correction image the same, adjust the color of the pixel according to the color of the correction region in the correction chart, so that the entire picture is not affected by the projection medium background splicing color, environmental factors and subjective factors, and the projection effect remains consistent. BRIEF DESCRIPTION OF DRAWINGS

[0047] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the accompanying drawings needed to be used in the embodiments or prior art description will be briefly introduced as follows. Obviously, the accompanying drawings in the following description only are some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor.

[0048] Figure 1 A projection scene schematic diagram of a projection device provided for some embodiments of the present application;

[0049] Figure 2 A light path schematic diagram of a projection device provided for some embodiments of the present application;

[0050] Figure 3 A circuit architecture schematic diagram provided for some embodiments of the present application;

[0051] Figure 4 A light path schematic diagram of a projection device provided for some embodiments of the present application;

[0052] Figure 5 A system framework schematic diagram of a projection device provided for some embodiments of the present application to realize display control;

[0053] Figure 6 A flowchart of a laser projection method provided for some embodiments of the present application;

[0054] Figure 7 A setting interface schematic diagram provided for some embodiments of the present application;

[0055] Figure 8 A projection setting interface schematic diagram provided for some embodiments of the present application;

[0056] Figure 9 A wall surface image schematic diagram provided for some embodiments of the present application;

[0057] Figure 10 A projection picture display area color region distribution schematic diagram provided for some embodiments of the present application;

[0058] Figure 11 A timing diagram of a laser projection method provided for some embodiments of the present application. DETAILED DESCRIPTION

[0059] In order to make the purpose and implementation of the present application more clear, the present application exemplary implementation will be clearly and completely described below by combining the accompanying drawings in the exemplary embodiments of the present application. Obviously, the described exemplary embodiments are only some embodiments of the present application, but not all the embodiments.

[0060] 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.

[0061] 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.

[0062] 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.

[0063] A projection device is a device that projects media data onto a projection medium. Projection devices can connect to computers, cable TV networks, the internet, VCD (Video Compact Disc), DVD (Digital Versatile Disc Recordable), game consoles, DV camcorders, and other devices via various interfaces to receive the media data to be projected. The media data includes, but is not limited to, images, videos, and text, while the projection medium includes, but is not limited to, physical forms such as walls, screens, and projectors.

[0064] Figure 1 This is a schematic diagram of a projection scene provided by a projection device in some embodiments of this application.

[0065] In some embodiments, the projection device can be a projector, laser TV, or other device with projection capabilities; this application does not limit the type of projection device. The projection device is used to project a projected image onto a projection medium. Taking a laser TV as an example, see [link to relevant documentation]. Figure 1 A laser TV may include a projector 2. The projection medium 1 is fixed in a first position, and the projector 2 is placed in a second position. By adjusting the relationship between the first and second positions, the projected image of the projector 2 is made to match the projection medium 1, that is, the second position is the optimal placement position of the projector 2.

[0066] Figure 2 This is a schematic diagram of the optical path of a projection device provided in some embodiments of this application.

[0067] The projector 2 includes a projection component, which includes a laser light source 210, an optical engine 220, and a lens 230. The laser light source 210 provides illumination for the optical engine 220, which modulates the light beam and outputs it to the lens 230. The lens 230 forms an image and projects it onto the projection medium 1, whereby the projection medium 1 displays the projected image.

[0068] In some embodiments, the laser source 210 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 optomechanical system 220. The optical lens assembly requires a high level of environmental cleanliness and airtightness; while the chamber where the laser assembly is installed can be sealed with a lower level of dustproof sealing to reduce sealing costs.

[0069] In some embodiments, the optical engine 220 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. The blue, green, and red optical engines constitute a three-color optical engine, which is used to modulate the laser used to generate user interface pixels.

[0070] In some embodiments, the light-emitting component of a laser TV can also be implemented using an LED (Light-emitting Diode) light source.

[0071] Figure 3 The circuit architecture diagrams provided for some embodiments of this application are shown.

[0072] In some embodiments, see Figure 3 The projector 2 may include a display control circuit 240, a laser light source 210, at least one laser driver component 250, and at least one brightness sensor 260. The laser light source 210 may include at least one laser corresponding to each of the at least one laser driver component. Here, "at least one" refers to one or more, and "more than one" refers to two or more.

[0073] In some embodiments, the laser source 210 includes three lasers corresponding one-to-one with the laser driving assembly 250. These three lasers can be a blue laser 211, a red laser 212, and a green laser 213, respectively. The blue laser 211 emits blue laser light, the red laser 212 emits red laser light, and the green laser 213 emits green laser light. The laser driving assembly 250 can be implemented as including multiple sub-laser driving assemblies, each corresponding to a laser of a different color.

[0074] In some embodiments, the display control circuit 240 is used to output light control signals corresponding to different primary colors to the laser driving assembly 250 to drive the corresponding laser to emit light. For example, the light control signals include blue light control signals, red light control signals, and green light control signals. See also Figure 3 The display control circuit 240 is connected to the laser driver assembly 250 and is used to output at least one light control signal corresponding one-to-one with the three primary colors of each frame in the multi-frame display image, and to transmit the at least one light control signal to the corresponding laser driver assembly 250. For example, the display control circuit 240 can be a microcontroller unit (MCU), also known as a single-chip microcomputer.

[0075] In some embodiments, the laser TV can achieve adaptive adjustment. For example, by setting a brightness sensor 260 in the light output path of the laser light source 210, the brightness sensor 260 can detect a first brightness value of the laser light source 210 and send the first brightness value to the display control circuit 240. The display control circuit 240 can obtain a second brightness value corresponding to the driving current of each laser, and when the difference between the second brightness value and the first brightness value of the laser is greater than a difference threshold, it determines that the laser has a COD (Catastrophic optical damage) fault. Then, the display control circuit 240 can adjust the current control signal of the laser driving component corresponding to the laser until the aforementioned difference is less than or equal to the difference threshold, thereby eliminating the COD fault of the laser, reducing the damage rate of the laser, and improving the image display effect of the projection device.

[0076] Figure 4 This is a schematic diagram of the optical path of a projection device provided in some embodiments of this application.

[0077] In some embodiments, see Figure 4 The optical path structure includes a laser source 210 and optical components 214. The laser source 210 may include independently configured blue laser 211, red laser 212, and green laser 213. This projection device can also be called a three-color projection device. The blue laser 211, red laser 212, and green laser 213 are all modular lightweight (Mirai Console Loader, MCL) packaged lasers, which are small in size and facilitate compact arrangement of the optical path.

[0078] In some embodiments, the projection host 2 may include a controller, which includes at least one of a central processing unit (CPU), a video processor, an audio processor, a graphics processing unit (GPU), RAM (Random Access Memory), ROM (Read-Only Memory), a first to an nth interface for input / output, and a communication bus. The controller is connected to relevant hardware of the projection device, such as display control circuitry, a brightness sensor, a distance sensor, and an image acquisition unit, to control the projection device's projection, focusing, calibration, screen on / off state adjustment, and other functions.

[0079] In some embodiments, the projection device (e.g., a laser TV) may be provided with several types of interfaces, such as a power interface, a USB interface, an HDMI (High Definition Multimedia Interface) interface, a network cable interface, a VGA (Video Graphics Array) interface, and a DVI (Digital Visual Interface) interface, to connect to a signal source for transmitting media.

[0080] In some embodiments, after the projection device is started, it can directly enter the display interface of the previously selected signal source, or the signal source selection interface. The signal source can be, for example, a preset video-on-demand program, or one of the following signal sources: HDMI interface, USB interface, live TV interface, etc. After the user selects the target signal source, the projector host 2 can obtain media data from the target signal source and project the media data onto the projection medium 1 for display.

[0081] In some embodiments, the projector 2 may be configured with an image acquisition device for coordinated operation to achieve relevant adjustments and controls on the projection process. For example, the projection device may be configured with a 3D camera, a monocular projector, or a binocular camera.

[0082] In some embodiments, the projector 2 can acquire images of the projection medium captured by an image acquisition device and divide the color regions according to the captured images. After the optical engine projects a solid color chart, the image acquisition device captures an image, and the reference region and correction region are determined based on the image. After the optical engine projects a color-variable chart, the image acquisition device captures an image. In the color-variable chart, the color of the reference region remains fixed, while the color of the correction region changes according to a certain pattern until the colors of the reference region and the correction region are the same in the captured image. The color of the correction region chart is recorded, the reflectance is calculated based on the color, and the projected image is adjusted based on the reflectance.

[0083] Figure 5 This is a schematic diagram of a system framework for implementing display control of a projection device provided in some embodiments of this application.

[0084] In some embodiments, see Figure 5 The system framework includes an application service layer, a process communication framework, an operation layer, a framework layer, a correction service, a camera service, a time-of-flight service, and hardware and its drivers. The controller of the projector host 2 controls the overall system architecture and implements projection control of the projection device based on the underlying program logic, including but not limited to functions such as automatic screen entry, automatic obstacle avoidance, automatic focus adjustment, anti-glare, screen on / off control, automatic correction and fine-tuning of the projected image, etc.

[0085] In some embodiments, the projection host 2 is also equipped with a distance sensor for detecting distance. The distance sensor may be a time-of-flight (TOF) sensor. The time-of-flight sensor measures the distance between nodes by using the round-trip flight time of the signal between the transmitting end and the reflecting end. After the time-of-flight sensor collects the distance data, it sends the distance data to the time-of-flight service. After the time-of-flight service obtains the distance data, it sends the collected distance data to the application service layer through the process communication framework. The distance data will be used for data calls of the controller, user interface, program application and other interactive uses.

[0086] In some embodiments, the projection host 2 may also be configured with an image acquisition device, which may be a monocular camera, a binocular camera, a depth camera, or a 3D camera, etc. The image acquisition device sends the acquired image data to the camera service, and then the camera service sends the image data to the process communication framework and / or the correction service. The process communication framework sends the image data to the application service layer, and the image data will be used for data calls, user interfaces, program applications, and other interactive applications of the controller.

[0087] In some embodiments, after the projection device completes automatic calibration, it can refocus. The controller detects whether the autofocus function is enabled. If the autofocus function is not enabled, the controller will terminate the autofocus operation. If the autofocus function is enabled, the controller performs focus calculation based on the distance detection value of the time-of-flight sensor.

[0088] In some embodiments, the controller queries a preset mapping table based on the distance detection value from the time-of-flight sensor. This preset mapping table records the mapping relationship between distance and focal length, thereby obtaining the focal length of the projection device corresponding to the distance detection value. The middleware then sends the obtained focal length to the optical engine of the projection device. After the optical engine emits a laser according to the aforementioned focal length, at least one image acquisition device captures an image of the projected content. The controller performs a sharpness detection on the projected content image to determine if the current lens focal length is suitable. If the focal length is unsuitable, refocusing is required. The projection device locates the focus position with the highest sharpness by adjusting the lens position, taking another image, and comparing the change in sharpness of the projected content image before and after adjustment.

[0089] If the judgment result meets the preset completion conditions, the automatic focus adjustment process ends; if the judgment result does not meet the preset completion conditions, the middleware will fine-tune the focal length parameters of the projector's optical engine, for example, by gradually fine-tuning the focal length according to a preset step size, and then setting the adjusted focal length parameters back to the optical engine. Through multiple steps such as taking pictures and evaluating sharpness, the optimal focal length is finally locked by comparing the sharpness of the projected image, thereby completing the automatic focus adjustment.

[0090] In some embodiments, at least a lens, a distance sensor, and an image acquisition device are disposed on the first plane of the projection host 2, and the image acquisition device may include one or more cameras. The first plane is a plane on the projection host 2 that is parallel to and opposite to the projection medium 1 during projection. It should be noted that the hardware and software configuration and system architecture of the projection device are not limited to the examples in the embodiments of this application.

[0091] The imaging principle of projection equipment is to separate the video signal into RGB three primary color image signals, and then control the RGB three primary color semiconductor laser generators to emit lasers of corresponding intensities. After modulation output and signal synchronization control, the laser beam is projected onto the screen, allowing the user to view the projected image. With the increasing demand for home entertainment and office use, laser projection technology has gradually become popular in the market. However, when traditional projection equipment projects onto walls of different colors, the image quality is often affected by the wall color, leading to color distortion and a decrease in image quality.

[0092] Projector devices have begun to offer wall color adaptive functionality. The technical principle behind wall color adaptive technology is to pre-set multiple commonly used colors in the device and set DLP (Digital Light Processing) parameters for each commonly used color. Then, the device uses a camera to detect the wall color and matches it with the pre-set colors, thereby adjusting the image display effect according to the DLP parameters corresponding to the pre-set colors.

[0093] Although the wall color is fixed, the color it appears to have is greatly affected by the environment (including weather, time, and lighting). The wall color will differ under different conditions, and using the same DLP parameters to adjust the projected image will not produce a stable display. For example, in strong light, the wall appears brighter, while in weak light, it appears darker. If the DLP parameters are set for a wall color under strong light, using the same DLP parameters to adjust the image in weak light will result in a suboptimal display. To achieve better projection results, specific DLP parameters need to be set for each color under different lighting intensities. However, this requires not only relying on the solution provider's DLP adjustments but also pre-setting a large number of DLP parameters for each color.

[0094] DLP parameters are set by engineers based on preset colors, and these parameters are those that engineers believe will produce a good projection effect. Therefore, the setting of DLP parameters is highly subjective and may even have negative effects.

[0095] Furthermore, DLP parameters can only adjust the display effect of a single wall color, but cannot handle walls with multiple colors using a uniform set of DLP parameters. Even if the display effect of different color areas can be adjusted using multiple DLP parameters, the display effect will vary when projected onto a wall with multiple colors due to the inability of preset colors to perfectly match the current wall color and the subjective influence of engineers setting DLP parameters.

[0096] To address the above technical problems, this application provides a projection device. The structure and functions of each part of the projection device can be found in the above embodiments. Furthermore, based on the projection device shown in the above embodiments, this embodiment further improves some functions of the projection device. For example... Figure 6 As shown, the controller performs the following steps:

[0097] Step S601: Acquire the projection medium image captured by the image acquisition device.

[0098] In some embodiments, the projection device has a built-in image acquisition unit.

[0099] In some embodiments, the projection device does not have an internal image acquisition unit, but an external image acquisition unit can be connected. For example, an image acquisition unit can be connected via a USB interface, and the controller can control the image acquisition unit to capture and acquire images captured by the image acquisition unit.

[0100] In some embodiments, before acquiring an image of the projection medium captured by the image acquisition device, in response to a user input command to open the settings interface, the optical engine 220 is controlled to project the settings interface onto the projection medium 1. The settings interface includes projection controls. In response to a user input command to select a projection control in the settings interface, the optical engine 220 is controlled to project the projection settings interface onto the projection medium 1. The projection settings interface includes a projection background color adaptation control. In response to a user input command to select a projection background color adaptation control in the projection settings interface, the image acquisition device is controlled to capture an image of the projection medium.

[0101] Users can input operation commands to the projection device via mobile terminals and control devices.

[0102] The mobile terminal can establish a communication connection with the projection device. The mobile terminal can open a specific application and input operation commands through the application. The mobile terminal can then send these commands to the projection device via the communication protocol corresponding to the communication connection. This communication connection can include Bluetooth and local area network (LAN) interconnection, among others.

[0103] The control device receives user input commands and converts them into control commands that the projection device can recognize and respond to. For example, the control device can be a remote control. Remote controls include infrared remote controls and Bluetooth remote controls. Operation commands can be input by pressing buttons on the control device or voice commands collected by pressing a voice button.

[0104] For example, after receiving a user's instruction to open the settings interface via a press control device, the optical engine 220 projects the settings interface onto the projection medium 1, such as... Figure 7 As shown. The settings interface includes projection control 71, image control 72, sound control 73, network control 74, Bluetooth control 75, AI control 76, general control 77, about control 78, and focus 79. Current focus 79 indicates that projection control 71 is selected. After receiving a command input by the user through pressing the confirmation key on the control device, the optical engine 220 projects the projection settings interface onto the projection medium 1, as shown. Figure 8 As shown. The projection settings interface includes an eye-protection control 81, a projection background color adaptation control 82, an installation method control 83, and a focus 79. Current focus 79 indicates that the eye-protection control 81 is selected. After receiving a user's command input via pressing the down and confirmation keys on the control device, the image acquisition device is controlled to capture an image of the projection medium.

[0105] It should be noted that controls refer to visual objects displayed in various display areas of the user interface on a display device to represent corresponding content such as icons, thumbnails, video clips, and links. These controls can provide users with various traditional program content received via data broadcasting, as well as various application and service content set up by content manufacturers.

[0106] The presentation of controls can be diverse. For example, a control may include text content and / or an image used to display a thumbnail related to the text content, or a video clip related to the text. Alternatively, a control may be text and / or an icon for the application.

[0107] The focus indicator is used to indicate that any control has been selected. On one hand, the focus object can be selected or controlled by the user through input from the control device, moving it between controls. For example, the user can use the arrow keys on the control device to move the focus object between controls. On the other hand, the focus object can be selected or controlled by the user through input from the control device, moving the controls displayed on the screen. For example, the user can use the arrow keys on the control device to move all controls left and right simultaneously, allowing the focus object to be selected and controlled while maintaining its position.

[0108] The way focus is indicated can be varied. For example, the focus object can be indicated by enlarging the control, by setting the background color of the control, or by changing the border, size, color, transparency, outline, and / or font of the text or image of the focus control.

[0109] In some embodiments, upon receiving a command from a user to press a combination of buttons on the control device, the step of controlling the image acquisition device to capture an image of the projection medium is executed. The combination of buttons includes multiple target buttons. The target buttons can be pressed simultaneously to trigger the projection background color adaptation operation. The target buttons can be pressed in a fixed order, and the time interval between adjacent button presses must not exceed a specific duration to trigger the projection background color adaptation operation.

[0110] In some embodiments, after receiving a user's instruction to press the voice button on the control device, the collected voice data is sent to the projection device. After the projection device recognizes the voice data as the "projection background color adaptation" voice instruction, it executes the step of controlling the image acquisition device to capture an image of the projection medium.

[0111] The high-definition camera of the image acquisition device captures an image of the current projection medium and sends the image to the controller.

[0112] Step S602: Determine the reference area and correction area in the projection medium image.

[0113] In this image, the reference area and the correction area have different colors.

[0114] After acquiring the projection medium image, image processing is performed on the projection medium image to obtain the color boundary line, and the reference area and correction area in the projection medium image are determined based on the color boundary line.

[0115] OpenCV (a cross-platform computer vision library) can be used for image processing to accurately extract the boundaries of different color regions on the projection medium. Image processing includes edge detection, color segmentation, and region labeling.

[0116] Edge detection and color segmentation: In OpenCV, the Canny function can be used for edge detection, and the inRange function can be used for color segmentation. Based on this, different color regions in the current image can be identified, and the boundaries between these regions can be determined.

[0117] Region labeling: In OpenCV, the `connectedComponents` function can be used for region labeling. Based on this method and the boundaries between color regions, different color regions can be labeled for use.

[0118] In some embodiments, the optical engine is first controlled to project a preset image card onto the projection medium, and the image acquisition device is controlled to capture an image of the projection area corresponding to the preset image card. Then, multiple color regions in the projection area image are determined based on color boundaries. After determining multiple color regions, the color similarity between the color corresponding to each color region and the preset color can be calculated. Then, the color region with the lowest color similarity among the multiple color regions is determined as the reference region, and the color regions other than the reference region are determined as the correction regions.

[0119] After obtaining the color boundary line, the optical engine 220 is controlled to project a preset pattern onto the projection medium 1 and the image acquisition device is controlled to capture an image of the projection area. The color of the preset pattern can be white, i.e., (R, G, B) is (255, 255, 255), or it can be any color, such as (R, G, B) is (220, 220, 220).

[0120] It should be noted that the preset image card must be a single color, and cannot be a combination of multiple colors.

[0121] After projecting the preset image card, the image acquisition device captures an image of the projected area and sends the image to the controller.

[0122] Optical-mechanical calibration technology is used to map the color boundary line onto the projection display area of ​​the projected image, thereby obtaining the coordinate information of the color boundary line in the projection display area. Based on this coordinate information, the projection display area can be divided into multiple color regions.

[0123] It should be noted that the projected area image can be the image of the plane on which the projection medium lies after the preset image card is projected. The projected display area refers to the display area of ​​the preset image card on the projection medium, which is only a part of the entire plane, i.e., a portion of the projected area image. This projected display area can be determined using optomechanical calibration technology.

[0124] For example, a projection medium image such as Figure 9 As shown, after OpenCV image processing, the boundary between color regions can be determined as line A. Using optomechanical calibration techniques, line A can be mapped onto the projection display area (dashed frame), obtaining the coordinate information of the boundary line within the projection display area, i.e., the line connecting points a1 and a2. This allows us to determine that the projection area can be divided into region 1 and region 2 based on color. The boundary line can be a straight line or a curve. There can be one boundary line or multiple boundary lines.

[0125] In some embodiments, the color corresponding to the color region and the preset color are converted from the first color space to a normalized second color space. Then, the distance between the color corresponding to the color region and the preset color in the second color space is calculated, and the color similarity between the color corresponding to the color region and the preset color is calculated based on the distance.

[0126] The first color space is different from the second color space. The preset color can be white, i.e., (R, G, B) is (255, 255, 255), or it can be any color, such as (R, G, B) is (220, 220, 220). The preset color can be the same as or different from the preset graphic color.

[0127] For example, the first color space is a color space built on the basis of red, green and blue, namely the RGB color space, and the second color space is a color space built on the basis of hue, saturation and value, namely the HSV color space.

[0128] Convert colors from the RGB color space to the HSV color space using the following method:

[0129] R' = R / 255;

[0130] G' = G / 255;

[0131] B' = B / 255;

[0132] Cmax = max(R', G', B');

[0133] Cmin = min(R',G',B');

[0134] Δ = Cmax - Cmin;

[0135] Hue calculates:

[0136] If Δ = 0, then H = 0°;

[0137] If Cmax = R', then H = 60° × ((G' - B') / Δ + 0);

[0138] If Cmax = G', then H = 60° × ((B' - R') / Δ + 2);

[0139] If Cmax = B', then H = 60° × ((R' - G') / Δ + 4).

[0140] Saturation calculation:

[0141] If Cmax = 0, S = 0;

[0142] If Cmax≠0, S=Δ / Cmax.

[0143] Value calculation:

[0144] V = Cmax.

[0145] h1, s1, and v1 represent the three HSV color space components of the color corresponding to the color region, respectively; h0, s0, and v0 represent the three HSV color space components of white, respectively. Δh, Δs, and Δv are the differences between the three components of the two colors, sqrt is the square root calculation, len represents the distance between the two colors in the HSV color space, and similarity is the degree of similarity. The similarity calculation method is as follows:

[0146] Δh = h1 - h0;

[0147] Δs = s1 - s0;

[0148] Δv = v1 - v0;

[0149] len=sqrt(Δh×Δh+Δs×Δs+Δv×Δv);

[0150] If len > 1, then len = 1;

[0151] similarity = (1.0 - len) / 1.0.

[0152] In the HSV color space, the closer the distance is to 0, the higher the color similarity and the closer the colors are; the farther the distance is, the lower the color similarity and the greater the color difference.

[0153] Select the region with the darkest color (the largest distance from the preset color and the smallest similarity) and record it as the reference region; record the other regions as the correction regions.

[0154] It should be noted that the reference region and the correction region can be represented using coordinate information. The reference region and the correction region in any projected image can be determined using their coordinate information.

[0155] For example, the default color is white. Figure 9 As shown, the color similarity between region 1 and white is similarity1, and the color similarity between region 2 and white is similarity2. Since similarity1 > similarity2, the color of region 2 is darker than the color of region 1. Region 2 is the reference region, and region 1 is the correction region.

[0156] If a lighter-colored area is used as the reference area, then since the white map is already the lightest color, areas darker than the reference area cannot be adjusted to the same color as the reference area by reducing the map's depth. In this embodiment, the darkest-colored area is used as the reference area, making it easier to adjust the color of other areas to the same color as the reference area by increasing the map's color depth.

[0157] In some embodiments, after determining the color boundary line of the projection medium image, it is not necessary to control the optical engine to project a preset image card onto the projection medium and control the image acquisition device to capture the projected image. The reference region and correction region in the projection medium image can be directly determined based on the color boundary line. Specific steps include: determining multiple color regions in the projection display area of ​​the projection medium image based on the color boundary line, and then calculating the area or number of pixels of each color region. Finally, the color region with the largest area or the most pixels among the multiple color regions is determined as the reference region, and the color regions other than the reference region are determined as the correction regions.

[0158] It should be noted that the image on the projection medium can be an image on the plane of the projection medium, while the projection display area refers to the area on which the projection image is projected onto the projection medium, which is only a part of the entire plane. This projection display area can be determined using optomechanical calibration technology when projecting any image.

[0159] For example, such as Figure 9 As shown, the number of pixels in region 1 is S1, and the number of pixels in region 2 is S2. S1 < S2, region 2 is the reference region, and region 1 is the correction region.

[0160] This application is applicable when, during subsequent projection of a calibration chart, the color of the reference area in the calibration chart is not white. Therefore, if the area with the largest area or the most pixels is not the darkest color, the area darker than the reference area can be adjusted to the same color as the reference area by reducing the depth of the calibration chart. Using the area with the largest area or the most pixels as the reference area reduces the computational load of pixel conversion in the projected image.

[0161] Step S603: Determine the calibration chart based on the reference area and calibration area in the projection medium image.

[0162] Step S604: Control the optical engine to project the calibration chart onto the projection medium and control the image acquisition device to capture the corresponding projection calibration image of the calibration chart.

[0163] In the calibration chart, the color of the reference area is different from the color of the calibration area.

[0164] After determining the reference area and the correction area, a correction chart is drawn based on these areas. The reference area of ​​the correction chart retains the preset colors and remains unchanged, while the colors of the correction areas change according to preset conditions. A projection correction image is captured each time the correction area color changes, and the captured projection correction image is used to determine whether further changes are needed.

[0165] For example, the reference area in the calibration chart is white, i.e., (255, 255, 255). The calibration area in the calibration chart changes in a certain step size. The step size is related to the computing power of the controller. If the controller has good computing power, the step size and preset value can be set smaller. If the controller has average computing power, the step size and preset value can be set larger. If the step size is set to 5, the color of the initial calibration area is (250, 255, 255). After projecting the calibration chart with the reference area color (255, 255, 255) and the calibration area color (250, 255, 255) onto projection medium 1, the projected calibration image is captured.

[0166] Step S605: Determine whether the color similarity between the correction region and the reference region in the correction image is higher than the preset similarity.

[0167] Calculate the color similarity between the corrected region and the reference region in the projected corrected image, and determine whether the color similarity is higher than the preset similarity.

[0168] The method for calculating color similarity is as follows:

[0169] Δh' = ha - hb;

[0170] Δs'=sa-sb;

[0171] Δv' = va - vb;

[0172] len'=sqrt(Δh'×Δh'+Δs'×Δs'+Δv'×Δv');

[0173] If len' > 1, then len' = 1;

[0174] similarity'=(1.0-len') / 1.0.

[0175] Where ha, sa, and va represent the three HSV color components of the reference region, and hb, sb, and vb represent the three HSV color components of the correction region. Δh', Δs', and Δv' are the differences between the three components of the two colors, sqrt is the square root calculation, len' represents the distance between the two colors in the HSV color space, and similarity' is the color similarity.

[0176] If the color of the correction area is more similar to the color of the reference area than the preset similarity, it means that the color of the correction area is the same as the color of the reference area. If the color of the correction area is less than or equal to the preset similarity, it means that the color of the correction area is different from the color of the reference area, and the color of the correction area in the correction chart still needs to be adjusted.

[0177] If the color of the correction area in the correction image is more similar to the color of the reference area than the preset similarity, proceed to step S606: adjust the pixel value of the correction area in the image to be projected according to the color of the correction area in the correction chart.

[0178] If the color similarity between the correction region and the reference region in the correction image is higher than a preset similarity, the color value of the correction region in the correction chart is recorded, and then the pixel values ​​of the correction region in the image to be projected are adjusted according to the color values. The color values ​​include red, green, and blue values.

[0179] The number of calibration regions can be one or more. When there are multiple calibration regions, if the color of one of the calibration regions is the same as the color of the reference region, the color of that calibration region is recorded. When calibrating other calibration regions, the colors of the already calibrated regions in the calibration chart can continue to change, or they can remain unchanged. When there are multiple calibration regions, the loop process can only terminate after the colors of all calibration regions are the same as the color of the reference region; that is, it is not necessary to execute the process of keeping the color of the reference region in the calibration chart unchanged while the colors of the calibration regions change according to preset conditions.

[0180] For example, such as Figure 10As shown, the projection area is divided into three regions: Region 1, Region 2, and Region 3, based on their colors. Region 1, with the darkest color, is designated as the reference region, while Regions 2 and 3 are designated as calibration regions. Region 1 in the calibration chart remains white, while the colors of Regions 2 and 3 change in increments. When the color of Region 2 in the calibration chart is (234, 234, 243), the color of Region 2 in the captured calibration image matches the color of Region 1, and this color is recorded. The color of Region 2 in the calibration chart remains constant at (234, 234, 243), while the color of Region 3 continues to change in increments until it reaches (220, 220, 210). In this case, the color of Region 3 in the captured calibration image matches the color of Region 1, and this color is recorded.

[0181] In some embodiments, the color values ​​of the correction area in the correction chart can be normalized to obtain the color reflectance, and then the pixel values ​​of the correction area in the image to be projected can be adjusted according to the color reflectance.

[0182] The red, green, and blue values ​​of the calibration area recorded on the calibration chart are normalized to obtain the reflectance of red, green, and blue, respectively. If the color of the calibration area on the calibration chart is (R1, G1, B1), then the reflectance of this area to the three primary colors of red, green, and blue in the current environment is: uRedCoeff = (255 – R1) / 255; uGreenCoeff = (255 – G1) / 255; uBlueCoeff = (255 – B1) / 255, respectively.

[0183] For example, the color of the correction area is (220, 220, 100), the red reflectance uRedCoeff = (255–220) / 255 = 0.0039, the green reflectance uGreenCoeff = (255–220) / 255 = 0.0039, and the blue reflectance uBlueCoeff = (255–100) / 255 = 0.6078.

[0184] In some embodiments, a gamma transform is performed on the pixels in the correction area of ​​the image to be projected to obtain a first color component of the pixel. Then, the first color component is adjusted based on the color reflectance to obtain a second color component. Finally, an inverse gamma transform is performed on the second color component to obtain the adjusted pixel value of the pixel in the correction area.

[0185] The first color component includes a first red component, a first green component, and a first blue component. The second color component includes a second red component, a second green component, and a second blue component.

[0186] Gamma transform is a non-linear image processing technique primarily used to adjust the brightness and contrast of an image. It improves the visual quality of an image by applying a non-linear function to change the intensity values ​​of image pixels, especially when processing overexposed or underexposed images. In this process, each pixel in the correction region of the original image to be projected undergoes a Gamma transform, converting it into a light signal.

[0187] The Gamma transform is referred to as the EOTF (electro-optical transfer function). The EOTF is a transfer function that takes an image or video signal as input and converts it into a linear light output for a display.

[0188] CsRGB represents the RGB channel values ​​of the original image to be projected, i.e., the pixel values ​​of the pixels in the correction area, and Clinear represents the converted light signal, i.e., the first color component.

[0189] If CsRGB < 0.04045, then Clinear = CsRGB / 12.92.

[0190] If CsRGB ≥ 0.04045, then Clinear = ((CsRGB + 0.055) / 1.055) 2.4 .

[0191] For pixels in different regions, the first color component is multiplied by the corresponding color reflectance to adjust the intensity of the light signal.

[0192] The second red component RClinear' = RClinear × uRedCoeff;

[0193] The second green component GClinear' = GClinear × uGreenCoeff;

[0194] The second blue component BClinear' = BClinear × uBlueCoeff.

[0195] Wherein, RClinear is the first red component, RClinear is the first green component, and BClinear is the first blue component.

[0196] The adjusted RGB components are subjected to inverse Gamma transformation to convert them back into electrical signals, thus obtaining the pixel values ​​of the input image.

[0197] The inverse Gamma transform is the OETF (opto-electronic transfer function). The OETF is a transfer function that takes scene light as input and converts it into an image or video signal as output.

[0198] CsRGB' is the value of the RGB channel of the image to be projected after adjustment, that is, the pixel value of the pixel in the correction area after adjustment, and Clinear' is the light signal after reflectivity adjustment, that is, the second red, green and blue components.

[0199] If Clinear' < 0.0031308, then CsRGB' = Clinear' × 12.92.

[0200] If Clinear' ≥ 0.0031308, then CsRGB' = 1.055 × Clinear' 1 / 2.4 -0.055.

[0201] It should be noted that the pixel values ​​in the reference area do not need to be adjusted.

[0202] The color of each pixel is adjusted based on the Gamma transformation. A Gamma transformation is performed during the conversion from an electrical signal to a light signal, and the converted light signal follows a linear change. Based on the calculated reflectance, the light signal in the correction area is multiplied by the corresponding red, green, and blue primary color reflectances, and then the intensity of the electrical signal is obtained through an inverse Gamma transformation, thereby determining the pixel value of the image to be projected.

[0203] Step S607: Control the optical engine to project the adjusted image onto the projection medium.

[0204] The adjusted image is modified pixel-by-pixel using GPU shaders and then projected. To ensure consistent display across different colored projection media, the target image can be modified pixel-by-pixel using GPU shaders. Based on the previously calculated reflectivity and Gamma transformation, the RGB values ​​of the image are adjusted pixel-by-pixel, and then projected through an optical engine, making the difference in background color almost invisible.

[0205] This application embodiment calculates the absorption ratio / reflectivity of red, green and blue colors, and realizes real-time frame-level GPU graphics color calculation and rendering based on the projection Gamma transformation principle. At the same time, it does not rely on the DLP adjustment of the solution provider, solves the problem of image difference caused by different home projection media colors in laser projection, ensures the overall projection effect is consistent, and restores the best original display.

[0206] For example, such as Figure 10As shown, the pixels in region 1 of the image to be projected remain unchanged. The color of region 2 is processed pixel by pixel, that is, the RGB components of each pixel are subjected to Gamma transformation, then multiplied by the reflectance of the color corresponding to region 2, and then subjected to inverse Gamma transformation to obtain the pixel value of each pixel in region 2. The color of region 3 is also processed pixel by pixel, that is, the RGB components of each pixel are subjected to Gamma transformation, then multiplied by the reflectance of the color corresponding to region 3, and then subjected to inverse Gamma transformation to obtain the pixel value of each pixel in region 3. The transparency remains unchanged, and the pixel-processed image to be projected can be projected. After calculating the reflectance of the three primary colors of each correction region, the pixel values ​​of the image to be projected can be automatically adjusted to achieve the function of matching the projection background color.

[0207] If the color similarity between the calibration region and the reference region in the calibration image is lower than or equal to a preset similarity, proceed to step S608: change the color of the calibration region in the calibration chart, and then proceed to step S604, that is, control the optical engine to project the modified calibration chart onto the projection medium and control the image acquisition device to capture the corresponding projected calibration image of the modified calibration chart. The color of the reference region in the calibration chart remains unchanged.

[0208] The color of the correction area can gradually deepen from white or gradually lighten from black, represented by changing the RGB values ​​in increments of 1. If the increment is 1, the color can be changed 256×256×256 times. The projection correction chart process can be terminated when the color similarity between all correction areas and the reference area exceeds a preset similarity.

[0209] For example, the reference area in the calibration chart is still white, i.e., (255, 255, 255). If the step size is set to 5, the color of the second calibration area is (255, 250, 255). After projecting the calibration chart with the reference area color (255, 255, 255) and the calibration area color (255, 250, 255) onto the projection medium, the calibration image is captured.

[0210] With a step size of one, the red, green, and blue values ​​can be decreased by 5 in sequence. With a step size of two, the red, green, and blue values ​​can be decreased by 10 in sequence, and two of the red, green, and blue values ​​can be decreased by 5 each, and so on. The subsequent color changes of the correction area are (255, 255, 250), (245, 255, 255), (255, 245, 255), (255, 255, 245), (250, 250, 255), (250, 255, 250), (255, 250, 250)……(0, 0, 0).

[0211] In some embodiments, such as Figure 11As shown, after receiving the user's instruction to perform projection background color adaptation, the controller sends a shooting instruction to the image acquisition unit. Upon receiving the shooting instruction, the image acquisition unit captures an image of the wall and sends it to the controller. The controller determines the color boundary coordinates based on the wall image and sends a command to the optical engine to project a white image. The optical engine projects the white image onto the projection wall. The controller sends a shooting instruction to the image acquisition unit. The image acquisition unit captures the projected image and sends it to the controller. The controller determines different color regions based on the color boundary coordinates, selecting the darkest color region as the reference region, and the remaining regions as correction regions. The controller sends a command to the optical engine to project a correction image. The reference region in the correction image remains white, and the color of the correction region is reduced by a fixed step from the RGB values ​​of the white region. The optical engine projects the correction image onto the projection wall. The controller sends a shooting instruction to the image acquisition unit. The image acquisition unit captures the corrected image and sends it to the controller.

[0212] The controller determines whether the colors of the reference area and the calibration area in the correction image are the same. If the colors of the reference area and the calibration area are not the same, it continues to send the projection correction chart command to the optical engine. The reference area in the calibration chart remains white, and the RGB values ​​representing the colors in the calibration area continue to decrease according to a certain pattern and fixed step size, which can represent a certain degree of color deepening. Another correction image is captured, and it is determined whether the colors of the reference area and the calibration area in the correction image are the same, ... until the colors of the reference area and the calibration area are the same. If the colors of the reference area and the calibration area in the correction image are the same, the color of the calibration area in the chart is recorded, and the color reflectance is determined based on this color. The pixel values ​​of the calibration area in the image to be projected are adjusted based on the color reflectance, while the pixel values ​​of the reference area are not adjusted; a projection command for the image to be projected is sent to the optical engine. The optical engine projects the adjusted image onto the projection wall.

[0213] This application embodiment captures images of a wall surface, performs edge detection, color segmentation, and region marking on the images to obtain the boundaries of different color regions. A white image card is projected and the image is captured, the similarity between each color and white is calculated, and a reference region is selected. The RGB values ​​of the correction region image card are gradually adjusted until the color distance between the correction region and the reference region is close to 0, and the RGB values ​​are recorded. Reflectivity is calculated based on the RGB values, and the light signals of other regions are multiplied by the reflectivity of the three primary colors of red, green, and blue, respectively. The electrical signal intensity is obtained through inverse Gamma transformation to determine the pixel values ​​of the input image. The image is processed pixel by pixel using a GPU shader, performing Gamma transformation, reflectivity adjustment, and inverse Gamma transformation. Finally, the adjusted image is projected through an optical engine to achieve color consistency.

[0214] This application embodiment detects the color of the projection surface and automatically adjusts the color parameters of the projected image, enabling the projected image to maintain high color fidelity and image quality on walls of different colors. This not only enhances the user's viewing experience but also expands the application scenarios of laser projection, allowing it to function in more environments.

[0215] Some embodiments of this application also provide a computer-readable storage medium that can store a program. When the computer storage medium is configured in a projection device, the program, when executed, can include the program steps involved in the laser projection method in the above embodiments. The computer storage medium can be a magnetic disk, optical disk, read-only memory (ROM), or random access memory (RAM), etc.

[0216] This application provides an electronic device, which includes:

[0217] processor;

[0218] Memory used to store processor-executable instructions;

[0219] The processor is used to read executable instructions from memory and execute the instructions to implement the laser projection method in the above embodiments.

[0220] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

[0221] For ease of explanation, the above description has been provided in conjunction with specific embodiments. However, the foregoing exemplary discussion is not intended to be exhaustive or to limit the embodiments to the specific forms disclosed above. Various modifications and variations can be made based on the foregoing teachings. The selection and description of the above embodiments are for the purpose of better explaining the contents of this disclosure, thereby enabling those skilled in the art to better utilize the embodiments.

Claims

1. A projection device, characterized by The method comprises the steps of: a light machine configured to project a projection picture to a projection medium; a controller coupled with the light machine and configured to: acquire a projection medium image captured by an image collector; determine a reference region and a correction region in the projection medium image, wherein the colors of the reference region and the correction region in the projection medium image are different; based on the reference region and the correction region in the projection medium image, determine a correction chart, wherein the color of the reference region in the correction chart is different from the color of the correction region; control the light machine to project the correction chart to the projection medium and control the image collector to capture a projection correction image corresponding to the correction chart; in the case that the similarity of the color of the correction region to the color of the reference region in the projection correction image is higher than a preset similarity, adjust the pixel value of the correction region in a to-be-projected image according to the color of the correction region in the correction chart, and control the light machine to project the adjusted to-be-projected image to the projection medium.

2. The projection device according to claim 1, characterized in that, The controller performing the step of determining the reference region and the correction region in the projection medium image is further configured to: perform image processing on the projection medium image to obtain a color demarcation line; determine the reference region and the correction region in the projection medium image according to the color demarcation line.

3. The projection device according to claim 2, characterized in that, The controller performing the step of determining the reference region and the correction region in the projection medium image according to the color demarcation line is further configured to: control the light machine to project a preset chart to the projection medium and control the image collector to capture a projection region image corresponding to the preset chart; determine a plurality of color regions in the projection region image based on the color demarcation line; calculate the color similarity of the color corresponding to the color region to a preset color; determine the color region with the minimum color similarity in the plurality of color regions as the reference region, and determine the color regions other than the reference region as the correction region.

4. The projection apparatus according to claim 3, wherein, The controller performing the step of calculating the color similarity of the color corresponding to the color region to the preset color is further configured to: convert the color corresponding to the color region and the preset color from a first color space to a second color space, wherein the first color space is different from the second color space; calculate the distance of the color corresponding to the color region to the preset color in the second color space; calculate the color similarity of the color corresponding to the color region to the preset color based on the distance.

5. The projection apparatus according to claim 2, wherein, The controller performing the step of determining the reference region and the correction region in the projection medium image according to the color demarcation line is further configured to: determine a plurality of color regions in the projection picture display region of the projection medium image based on the color demarcation line; calculate the area or the number of pixels of the color region; determine the color region with the maximum area or the most number of pixels in the plurality of color regions as the reference region, and determine the color regions other than the reference region as the correction region.

6. The projection apparatus according to claim 1, wherein, The controller performing the step of adjusting the pixel value of the correction region in the to-be-projected image according to the color of the correction region in the correction chart is further configured to: normalizing the color value of the correction region in the correction chart to obtain a color reflectance; adjusting the pixel value of the correction region in the image to be projected according to the color reflectance.

7. The projection apparatus according to claim 6, wherein, The controller is further configured to: perform gamma transformation on the pixel points of the correction region in the image to be projected to obtain first color components of the pixel points; adjust the first color components based on the color reflectance to obtain second color components; perform inverse gamma transformation on the second color components to obtain the adjusted pixel value of the pixel points of the correction region.

8. The projection apparatus according to claim 1, wherein, The controller is further configured to: change the color of the correction region in the correction chart when the similarity between the color of the correction region and the color of the reference region in the projection correction image is equal to or lower than a preset similarity; control the optical machine to project the changed correction chart to the projection medium and control the image collector to capture a projection correction image corresponding to the changed correction chart.

9. A laser projection method, characterized by, The method comprises: capturing an image of the projection medium by the image collector; determining the reference region and the correction region in the projection medium image, wherein the color of the reference region is different from the color of the correction region in the projection medium image; determining a correction chart based on the reference region and the correction region in the projection medium image, wherein the color of the reference region in the correction chart is different from the color of the correction region in the correction chart; controlling the optical machine to project the correction chart to the projection medium and controlling the image collector to capture a projection correction image corresponding to the correction chart; adjusting the pixel value of the correction region in the image to be projected according to the color of the correction region in the correction chart when the similarity between the color of the correction region and the color of the reference region in the projection correction image is higher than a preset similarity, and controlling the optical machine to project the adjusted image to be projected to the projection medium.

10. A computer-readable storage medium, characterized in that, The storage medium stores a computer program for executing the laser projection method in claim 9.

Images